2 international Conference on Transport infrastructuresnd

Rita Fortes Paulo Pereira

international Conference on Transport infrastructures iCTi2010Book of ProceedingsHotel Ibirapuera So Paulo, Brazil 4 - 6 August, 2010

Edited by

Rita Moura FortesEscola de Engenharia Universidade Presbiteriana Mackenzie, Brasil

Paulo PereiraEscola de Engenharia Universidade do Minho, Portugal

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Universidade do Minho Escola de Engenharia Departamento de Engenharia Civil, Campus de Azurm, P-4800-058 Guimares, Portugal Telefone: +351 253 510 240; Fax: +351 253 510 217 ISBN: 978-972-8692-57-5

International Organizing CommitteeCommittee Chair: Rita Fortes, Universidade Presbiteriana Mackenzie, Brazil Committee Co-Chairs: Joo Merighi, Universidade Presbiteriana Mackenzie, Brazil Paulo Pereira, iSMARTi President, Universidade do Minho, Portugal Rui Margarido, ANDIT Director, Brazil Tien F. Fwa, iSMARTi Executive President, National University of Singapore, the Republic of Singapore Waheed Uddin, former iSMARTi President, CAIT Director, The University of Mississippi, USA

International Scientific Committee (in alphabetical order)Committee Chair Tien F Fwa, National University of Singapore, The Republic of Singapore Committee Members Adelino Jorge Lopes Ferreira, Universidade de Coimbra, Portugal Alan R Woodside, University of Ulster, UK Alessandro Marradi, University of Pisa, Italy Alex Visser, University of Pretoria, South Africa Ali Selim, SD State University, USA Andreas Loizos, National Technical University of Athens, Greece Athanassious Papagiannakis, University of Texas-San Antonio, USA Basil Psarianos, National Technological University of Athens, Greece Bertha Santos, Universidade da Beira Interior, Portugal Cesare Sangiorgi, Universit di Bologna, Italy Elisabete Freitas, Universidade do Minho, Portugal Ezio Santagata, Politecnico di Torino, Italy Filippo Giammaria Pratic, Mediterranean University of Reggio Calabria, Italy Frank B. Holt, Dynatest International, USA Ghim Ping Ong, Purdue University, USA Glicrio Trichs, Universidade Federal de Santa Catarina, Brazil Hugo Silva, Universidade do Minho, Portugal Jan Celko, University of Zilina, Slovak Republic Joana Peralta, Universidade do Minho, Portugal Joo Merighi, Universidade Presbiteriana Mackenzie, Brazil Joel Oliveira, Universidade do Minho, Portugal Jorge C. Pais, Universidade do Minho, Portugal Jos Alberto Pereira Ribeiro, ANEOR, Brazil Jose Tadeu Balbo, Escola Politcnica da USP, Brazil Jos Leomar Fernandes Junior, Escola de Engenharia de So Carlos, USP, Brazil Jos Neves, Instituto Superior Tcnico, Portugal Kanok Boriboonsomsin, University of California Riverside, USA Liedi Bernucci, University of Sao Paulo, Brazil Lus de Picado Santos, Universidade de Coimbra, Portugal Manuel Minhoto, Instituto Politcnico de Bragana, Portugal Massimo Losa, University of Pisa, Italy Mohammed Memon, PhalTech Corporation, President, USA Murat Ergun, Technical University of stanbul, Turkey Nestor Wilfredo Huaman Guerrero, Universidad Nacional de Ingeniera, Lima, Peru Paulo Pereira, Universidade do Minho, Portugal Ramzi Taha, Sulan Qaboos University, Oman Rita Moura Fortes, Universidade Presbiteriana Mackenzie, Brazil Rosa Luzia, Instituto Politcnico de Castelo Branco, Portugal Rui Margarido, Andit Director, Brazil Silvino Capito, Instituto Superior de Engenharia de Coimbra, Portugal Sushant Upadhyaya, GeoConcepts Engineering, USA Tien F Fwa, National University of Singapore, The Republic of Singapore Waheed Uddin, The University of Mississippi, USA Wynand JvdM Steyn, University of Pretoria, South Africa Secretariat I. Virginia Fernndez

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PREFACE

A suitable transport infrastructure has always been essential for the mobility of the persons and goods all over the world since remote ages. Most of the transport infrastructures have been developed under national policy premises. There is the need to establish a single, multimodal system integrating land, sea and air transport connections which ensure the sustainability of our transport networks into the future. Environmental protection requirements are also the key to development sustainability and should not be left apart. The worldwide awareness of the sustainability of life and nature is indicative of an important role that civil infrastructures play in guaranteeing a sustainable life quality. Once an infrastructure is constructed its life-cycle demands a great effort in terms of maintenance and rehabilitation, in order not to jeopardize the initial investment in infrastructure assets and not to degrade surrounding and global environment. Thus, the iCTi series has been implemented with the support of a permanent organization, a technical and learned society iSMARTi with the aim of disseminating the most recent research in the themes approached in this international conference. After its first Conference in China, this second ICTI welcomes you in So Paulo, Brazil.

CONTENTS

Preface

vii 1 3

Keynote Lecture Toward an European Interoperable Rail Network: the Way to Build a Competitive Network P. Cicini

Application of new materials, concepts and technologies Measuring Asphalt-Aggregate Bond Strength Under Different Conditions H. Bahia, Raquel Moraes, Raul Velsquez Design and Performance Analysis of Foamed Asphalt Treated Mixtures A. Marradi, G. Ridondelli, U. Pinori Performance Study of Different Stabilizers Addition on 50% Dry Sludge from Water Treatment Plant (WTP) of Taiaupeba to Use as Compacted Material in Earthwork Ditches R. Moura Fortes, J. Merighi, D. Pauli, M. Barros, M. de Carvalho, N. Menetti, . Barbosa, B. Bento Changes in the Rubber Morphology Caused by the Interaction with Bitumen J. Peralta, H. Silva, J. Pais, A. Machado New Experimental Methods to Monitor and Characterize Asphalt Rubber Binders J. Peralta, H. Silva, J. Pais Monitoring Rubber Swelling and De- and Re-vulcanization through AR Elastic Recovery J. Peralta, H. Silva, J. Pais, A. V. Machado A Laboratory Study on the Fatigue Performance of Warm Mix Asphalt Mixtures J. Oliveira, H. Silva, P. Pereira, L. Moreno Laboratory Results Obtained On New Asphalt Mixtures With Polymer Modified Bitumen C. Rcnel, A. Burlacu, C. Surlea Use of Tire Rubber to Improve Fatigue Performance of Asphalt Mixtures L. P. Thives, G. Trichs, P. Pereira, J. Paisix

13 15 25

35

45 55 65 75

85 95

Application of Polypropylene Fibers in Pervious Concrete Pavement K. Behfarnia, S. Abtahi, A. R. Hejazi Evaluation of Usage of Gilsonite as an Additive for Modification of Asphalt Cement A. Mansourian, M. Ameri, S. Salehi Durable Asphalt Surfaces With High Crack Resistance F. Dourado, J. Scherer High Tenacity Acrylic Fibres in Bituminous Mixtures B. Pereira, J. Contreiras, A. Teixeira, M. Azevedo Studies of Bituminous Mixtures with Acrylic Fibers A. Teixeira, B. Pereira, J. M. Contreiras, M. C. Azevedo Comparative Study of a Mechanistic Resilient Modulus Predictive Equation for Unbound Materials C. Cary, C. Zapata Effects of the Rheological Properties of Mastics on Creep Performance of Asphalt Concretes H. M. Zelelew, A. T. Papagiannakis Asphalt Concrete with Low-Viscosity Modifier M. Iwaski, G. Mazurek Innovative Technologies for the Determination of the Density of Bituminous Mixtures F. G. Pratic, A. Moro A Theoretical Investigation on the Dependence of Gmb Measurements on Boundary Conditions F. G. Pratic, A. Moro Effect of Oil Palm Fiber on Properties of Asphalt Binders S. Anwar Vijaya, M. Karim, H. Mahmud Prospect of Using Waste Cooking Oil as Rejuvenating Agent for Aged Bituminous Binder M. R. Karim, H. Asli Effect of the Adhesion between Layers of Airport Pavements in their Structural Behavior L. Silva, P. Cachim, A. Benta Experimental Comparative Analysis of Laboratory Compaction Methodologies for Stabilized Soils G. Dondi, C. Sangiorgi, C. Lantieri, R. Cancellieri, P. Violax

107 115 125 131 139

147

157 167 177

187 197

205

215

225

The Use of Steel Fibers as a Reinforcement Material in Cement Concretes C. A. Kiremitci, S. Iyinam, A. F. Iyinam, M. Ergn Rheology of Fractionated Cornstover Bio-oil as a Pavement Material Mohamed Abdel Raouf, R. Christopher Williams Re-Capsulation of Styrene Butadiene Styrene (SBS), Styrene Butadiene (SB) with X-Linking Agent for Asphalt Modification G. Zamora, G. Memon Laboratory Investigation of Moisture Movement in Asphalt Concrete D. Bateman, R. Tarefder Identification of a Fuel Contamination Problem in the Production of Warm Mix Asphalts H. Silva, J. Oliveira, J. Peralta, C. Ferreira Use of Lime-Bagasse Ash for Subgrade Soil Stabilization T. Akram, A. Q. Khan Applications of spaceborne and airbone remote sensing technologies Remote Sensing and Geospatial Technologies for Inventory and Condition Monitoring of Transport Infrastructure Assets Waheed Uddin Optimal utilization and allocation of resources for maintenance management Natural and alternative Materials for Road Construction Environmental Optimization of Resources Management in a Territory D. Franois, T. Martaud, C. Ropert, E. Rayssac, A. Jullien, C. Proust Evaluation of Asphalt Plants in Terms of Performance: A Case Study for Turkey F. Yonar, S. yinam, A. F. yinam, M. Ergn Wheel Tracking Performance of Asphalt Concrete Mixture with Conventional and Modified Bitumen A. F. Nikolaides, E. Manthos Analysis of Full Scale Test Data to Study the Load Transfer Efficiency of Rigid Airfield Pavement Joints A. Wadkar, W. Kettleson, L. Musumeci, A. Zapata, Y. Mehta, Douglas Cleary Approach to Road Maintenance Works on Performance Criteria M. Dicu, C. Rcnel, A. Burlacu, C. Surlea Assessment of Fatigue Resistance and Aging of Asphalt Mixtures in Portugal J. Dias, F. A. Batista, M. G. Lopesxi

235 245

255 265 275 285

295 297

307 309 317

327

337 347 355

Use of Construction and Demolition Waste as a pavement material in So Lus Brazil W. SantAna, T. Ferreira, L. Bernucci, R. Motta

363

Infrastructure asset management techniques and strategies A Simple Tool for Applying Sustainability Principles to Road Rehabilitation Strategy Michael L. J. Maher, Robert Noel-De-Tilley, Robert A. Douglas Use of 3D Laser Profiling Sensors for the Automated Measurement of Road Surface Conditions (ruts, cracks, texture) D. Lefebvre, Y. Savard, J. Laurent, J. F. Hbert, R. Habel The Effect of Geometric Features on Flexible Pavement Damage Using In-Service Pavement Performance Data Case Study H. Salama, N. Gonah, A. Wahdan, M. Solyman Road Pavements Maintenance through High Performance Measurement E. Cesolini, S. Drusin Utilizing Traffic Moulding of Road Pavements Towards More Cost Efficient Pavement Design and Management E. Kleyn, W. J.vdM. Steyn Multi-Objective Decision-Aid Tool for Pavement Management A. Ferreira, S. Meneses, M. Trindade Use of WIM Data to Evaluate Growth Including Economic Activities Attributed to Reconstruction of a Warranty Road R. Tarefder, N. Sumee A Preliminary Comparison of Continuous Compaction Control and Portable FWD systems for Qc/Qa A. Marradi, U. Pinori, C. Sangiorgi, C. Lantieri Precision and Bias Measurements in Automated Cracking Surveys and Future Technologies K. Wang Evaluation of Aircraft Landing Hydroplaning Risk H. R. Pasindu, T. F. Fwa, G. P. Ong Results of Accelerated Load Tests in Slovenia Marjan Tuar, Mojca Ravnikar Turk Combining FHWA and EVALIV Spreadsheets for Forwardcalculating Subgrade and Pavement-Layers Moduli M. Livnehxii

373 375

385

395 405

415 427

437

447

457 469 479

489

Modifications to Pass-to-Coverage Ratio Computation in the FAAs FAARFIELD Design Procedure I. Kawa, G. Hayhoe, D. Brill Improvemets of Neural Networks Application for Backcalculation D. Cunha, S. Fontul, M. G. Lopes Construction of New Road Infrastructure in Poland with Emphasis on Bridge Structures J. Biliszczuk, J. Onysyk, M. Suchy Use of Trenchless Repair and Renewal Technologies in Roadway Drainage Infrastructure Management O. M. Salem, B. Salman, M. Najafi, A. Moawad HMA Composition vs. Surface Characteristics: Issues and Perspectives to Optimise Road Asset Management F. G. Pratic, R. Vaiana, A. Moro, T. Iuele New Methods of Traffic Growth Forecasting for Mechanistic-Empirical Pavement Design Guide (MEPDG) K. Hall, X. Xiao, Y. Jiang, K. Wang Analyzing the Sensitivity of Error in Data Collection for Pavement Overlay Designing M. Khabiri Additional Road User Costs due to Pavement Conditions and Maintenance Actions: Initial Approach for Portuguese Conditions B. Santos, L. Picado-Santos, V. Cavaleiro Analysis of Aircraft Inflatable Slide Evacuation Events V. Motevalli Freight Traffic on High Speed Rail Line D. Leal, L. Picado-Santos Sustainable transportation and urban development Multimodal Transport Infrastructure Policies to Support Safe, Efficient and Reliable Freight Operations: A Case Study of the United States G. P. Ong Role of Multimodal Urban Transportation Infrastructures in Sustainable Integrated Transportation and Urban Planning: Lessons Learnt from the United States and Asia G. P. Ong New Bus Rapid Transit System: Significant Contribution to Public Transit Infrastructure of Istanbul S. Topuz Kiremitci, S. Iyinam, A. F. Iyinam, M. Ergnxiii

499 511 521

531

549

531 559

567 577 587

597 599

609

619

Connecting two Continents: Marmaray Rail Transit Project of Istanbul C. A. Kiremitci, P. Alpkokin, M. Ergn, S. Topuz Kiremitci Effect of Transportation Infrastructure Investments on Urban Development; Case of Istanbul Y. Eryilmaz, M. Ergn Optimization of Bus Transport in Istanbul A. S. Kesten, M. Ergn Sustainable Personal Rapid Transit Strategies for Congested Cities and Urban Communities W. Uddin, U. Uddin

627

635

645

655

Environmental and social impact assessment Tribological and Environmental Effects in Dry and Wet Pavement-tyre Interaction: Modelling and Experiments F. G. Pratic, R. Ammendola, A. Moro Urban Road Safety Evaluation of Road Safety Measures C. Carvalheira, L. Picado-Santos Terrestrial Transport Infrastructures Effects on Natural Territories Development of a Quantitative Evaluation Method D. Franois, A. Ginot, S. Hennique, A. Jullien

667

669

679

689

Life cycle costing Road Base Stabilization: Performance Improvement and Pavement Life Cycle Consequences F. G. Pratic, M. Giunta, P. DAgostino The use of Boundary Element Method to Establish a Pavement Response A. Almeida, L. de Picado-Santos Thin Surfacing and Micro-Surfacing Alternative Cost Effective Wearing Course Materials A. Nikolaides Experimental Investigation of a Cement-Stabilized Low-Strength Soil for Pavement Construction in Eastern Nigeria R. Oduola

697

699

711

721

731

xiv

Keynote Lecture

iCTi2010, Fortes & Pereira (eds.) 2010, ISBN 978-972-8692-57-5

Toward an European Interoperable Rail Network: the Way to Build a Competitive Network.P. CiciniCommercial and Operation Network Direction, Infrastructure Manager Italian Railways (RFI) , Italy p.cicini@rfi.it

ABSTRACT: T Between 1970 and 1998 the share of the goods market carried by rail in Europe fell from 21,1% to 8,4%, even though the overall volume of transported goods rose considerably. In the last years it has remained at the same value. The rail transport must regain a little slide of market. The objective proposed by the European Union on the White Paper is to increase the market share from 6 to 15% by 2020. It means to have an infrastructure suitable for modern transport and conditions of interoperability between networks and systems. Though it will not be possible in the immediate future to establish a complete rail network dedicated to freight, the investments must encourage the gradual development of trans-European corridors for priority or even exclusive use by freight trains. Parallel to the priority freight corridors an high speed passengers network is required. It includes high-speed lines, upgraded lines, connections and nodes. The rail offer must became more attractive and competitive than it is today. the European Union financed studies, developed by a groups of railway experts, to find a common command and control train system. They agreed in utilize the European Railway Traffic Management System (ERTMS). Six priority corridors have been identified, together with the technical and financial conditions required for a more rapid deployment of ERTMS. In this paper will be showed the planned actions to ensure the conditions of interoperability between networks and systems. KEY WORDS: ERTMS, Interoperability, Freight, Corridors, Rail network. 1. INTRODUCTION Between 1970 and 1998 the share of the goods market carried by rail in Europe fell from 21,1% to 8,4%, even though the overall volume of transported goods rose considerably. In the last years it has remained at the same value. The rail transport must regain a little slide of market. The objective proposed by the European Union on the White Paper is to increase the market share from 6 to 15% by 2020. The rail offer must became more attractive and competitive than it is today. It means to have an infrastructure suitable for modern transport and conditions of interoperability between networks and systems. In the last years the European Union actions have been directed to allow the development of multimodal corridors, giving priority to freight, and of high speed network for passengers. The establishment of multimodal corridors giving priority to freight, requires high quality rail infrastructure. The physical characteristics of the railways in Europe do not lend themselves to a mass transport system for freight. Nor is it possible to stack containers or3

make up long trains, and generally the system has to cope with dense passenger train traffic, sharing the same infrastructure with the freight trains. Though it will not be possible in the immediate future to establish a complete rail network dedicated to freight, the investments must encourage the gradual development of transEuropean corridors for priority or even exclusive use by freight trains. They consist mainly of existing lines used primarily or even exclusively by freight trains. In areas with intensive traffic, particularly urban areas, having separate lines for freight and passengers will be guiding the principle in the development of the network, which will require the construction of new lines or loop lines around the nodes. In other areas, the gradual establishment of corridors giving priority to freight will be achieved through the improvements in capacity including the upgrading and rehabilitation of infrastructure on alternative low traffic ways or through the development of traffic management system. Parallel to the priority freight corridors an high speed passengers network is required. It includes high-speed lines, upgraded lines, connections and nodes. Passengers and priority freight networks objectives are not in contrast; on the contrary they are both part of the same effort to increase the capacity of the whole rail network and to aim to have specialized lines. High speed lines or upgraded lines aid the availability of the line for the freight by freeing up the lines previously used by passenger trains. In this paper will be showed the planned actions to ensure the conditions of interoperability between networks and systems. 2. STATE OF ART European Rail is a mixture of ancient and modern. On one side there are high performance high speed lines, served by modern stations, on the other side there are old freight services and old suburban lines at saturation point. Europe is a sum of different Countries. Each Country uses its own technology, in terms of rail gauge, electricity voltage (Figure 1), rolling stock design etc. and has got its own different train control and command system, that generally is stand alone and not-interoperable.

Figure 1: Rail electrification system in Europe There are more than 20 train control systems and 17 train radio systems (Figure 2), that together with other technologies, create a physical barrier to international traffic and loosetime at the border.

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Figure 2: Train control and radio systems in Europe The Thalys trains, running between Paris, Brussels, Cologne and Amsterdam have to be equipped with seven different train control systems. Each one is extremely costly, in terms of installation and maintenance, and takes up space on-board. Obviously, interoperability does not mean only technology but also operation rules. It takes 30-40 minutes to replace the locomotive on a freight train and to check that the train is in proper working order (change of locomotive, fill out the composition form, check of the brakes, change of driver and crew, inspection of the train, carry out checks on dangerous materials, check of documents, make up the train, label of the wagons, train report, check of the rear light). In the last years, the European Union financed studies, developed by a groups of railway experts, to find a common command and control train system. The first important European Union step was the directive 96/48/EC established that the interoperability conditions for high speed lines were guaranteed by European Rail Traffic Management System ERTMS and gave the technical rules guidelines to realize it. In the 2001, with the directive 2001/16/EC, ERTMS was extended to the conventional rail network, defining the Technical Specifications of Interoperability (TSI). The specifications were subsequently reviewed to include additional functionalities and better join the needs of the railway companies and infrastructure managers. To ensure that ERTMS is constantly adapted to the railways needs, technical specifications are maintained under the lead of the European Railway Agency in cooperation with signaling industries and railway stakeholders. In parallel to the specifications work, a joint effort from the European Union and the member States to finance ERTMS has been implemented. In 2005 and in 2008 European Union and railway stakeholders signed two Memorandum of Understanding to further deploy ERTMS on Europeans corridors (Figure 3).

5

Figure 3: The legal framework More specifically the Memorandum of 4th July 2008 settles a cooperation framework for the main public and private rail actors to reach a common technical standard. This standard is scheduled to enter into force at the end of 2012. Six priority corridors have been identified, together with the technical and financial conditions required for a more rapid deployment of ERTMS. They interest a little less than 13.000 km of lines and were defined in terms of existing and future volumes of traffic. Some internal lines of the main States are already equipped with ERTMS, but they do not have the continuity, necessary to give competitiveness to international traffic. Crafted financial incentives were assigned to support both infrastructure and on-board installations. 3. THE INTEROPERABLE CORRIDORS The European Deployment Plan aims at filling up the network gaps an terms of technology and operation. It ensures that the Member States respect the National Deployment Plan for the tracks of European importance. It promotes and follows a corridor approach. Two important milestones were fixed: 2015: specific corridor sections have to be equipped, according to national deployment plans; 2020: the main freight zone throughout Europe should be linked to one another through the corridors. Necessary condition to reach the interoperability is an effort to develop bilateral crossacceptance of the rolling stock and the operational rules. It means to improve co-operation and procedural coordination among national safety authorities and notified bodies; it is necessary to standardize the tracks and the on-board equipment and harmonize testing specifications, references and procedures. The last but not less important point is to harmonize the operational rules, such as the driver licenses, trans-boundary operations, single train standards. Six priority corridors have been identified and planned to become interoperable with the joined effort of European Union and Member States. They are named "A" to "F", (Figure 4):

6

Figure 4: The six European interoperable corridors 4. THE ERTMS The European Railways Management System (ERTMS), the unique system train control designed to gradually replace the existing incompatible European systems. It is constituted by two basic components: ERTMS = ETCS + GSM-R ETCS, European Train Control System, is the new automatic train protection system (ATP) to replace the existing national ATP-systems. It ensures adequate safety margin between trains. The speed limits are transmitted from the track to the train, the drivers screen shows permitted maximum speed and the on-board computer stops the train if the speed exceeds the permitted maximum value (Figure 5); Corridor A: Rotterdam Genova Corridor B: Stockholm Napoli Corridor C: Antwerp-Base-Lyon Corridor D: Valencia-Lyon-Ljubliana-Budapest Corridor E: Dresden-Prague-Budapest Corridor F: Duisburg-Berlin-Warsaw

Figure 5: Train Control System GSM-R, the new radio system for providing voice and data exchange between the driver and the central control, based on standard GSM using frequencies reserved for rail application with specific and advanced functions (Figure 6).

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Figure 6: Radio System These two components form ERTMS, the new signaling and management system for Europe, enabling the technological part of interoperability on European Rail Network. Due to the nature of the required functions, the ERTMS installation is part on the tracks and part an board of the trains. 4.1. ERTMS Levels A train equipped with ERTMS/ETCS on board equipment always co-operates with the ERTMS/ETCS track equipment in a defined ERTMS/ETCS level. ERTMS/ETCS can be configured to operate in one of the following application levels. Level 0. The train is equipped with ERTMS/ETCS and operates on a line without ERTMS/ETCS. Level 1 with or without infill transmission. The train is equipped with ERTMS/ETCS and operates on a line equipped with the eurobalises and optionally the euroloop or the radio infill. It overlies to the existing signaling system; the movement authorities are managed through the eurobalise and the trains integrity and position are managed by the track circuit (Figure 7).

Figure 7: ERTMS/ETCS Level 1 A variant is represented by the infill (euroloop, radio or extra balises) (Figure 8).

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Figure 8: ERTMS/ETCS Level 1 with infill Level 2. The train is equipped with ERTMS/ETCS and operates on a line controlled by a Radio Block Center and equipped with the eurobalises and the euroradio. In this case the trackside signals are not more required; the movement authorities are managed through GSMR and the train position is managed through the eurobalises (Figure 9).

Figure 9: ERTMS/ETCS Level 2 Level 3. It is similar to level 2 but the train location and the train integrity supervision are based on information received by the train. It overpasses the concept of fixed blocks with the concept of dynamic blocks, not linked any more to a pre-determined physical space, but created depending on the traffic conditions (Figure 10).

Figure 10: ERTMS/ETCS Level 3

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It is possible to overlay several application levels on the same track. Level 1, 2 and 3 are downwards compatible. It means that a level 3 equipped train can operate in level 1 and 2, and level 2 equipped train can operate in level 1. 5. ORGANISATION A stable corridor organisation has to follow the projects development to guarantee the success. The Letter of Intent, signed by the Ministries of the Member States in agreement with the European Union, gives the start to the project, settling the objectives and the deadlines. It is based on the reciprocity principle: it must be guaranteed that the traffic can cross the border and run in both directions between two Countries, at the same conditions. The project maintains strongly the corridor vision (Figure 11).

Figure 11: Corridors general structure organisation The corridor organisation has at the top level the Executive Board, constituted by the Representatives of the Ministries with the attendance of Infrastructure Manager, has the role of interface between Ministries and European Union. The operative role is managed by the Management Committee, constituted by the Representatives of Infrastructure Manager, with the task to manage and upgrade the Business Plan, and to make proposals for the corridor optimisation. The technical aspects are analysed and shared in the permanent working groups. It is advisable to have a legal structure for the corridor organisation (EEIG). This is a general structure but every corridor has little differences. 6. CONCLUSIONS The interoperability is a necessary step towards an integrated and competitive network. The deployment of ERTMS must be integrated into an broader approach including infrastructure and operational issues. Necessary condition to reach the interoperability is an effort to develop bilateral cross-acceptance of the rolling stock and the operational rules. It means to improve co-operation and procedural coordination among national safety authorities and notified bodies. The six identified priority corridors, planned to become interoperable, represent the first step of a more extended European interoperable rail network.

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REFERENCES European Commission. White Paper European transport policy for 2010: time to decide. 2001. Commission Decision of 30 May 2002 concerning the technical specification for interoperability relating to the infrastructure subsystem of the trans-European high-speed rail system referred to article6 (1) of Council Directive 96/48/EC. ERA- Applicable standards in HS Infrastructure subsystem TSI 2008/217/ECERTMS European Interoperable Corridors eu.europa.eu ERTMS Interoperabilit RFI. www.rfi.it ERTMS The official website. www.ertms.com ERTMS Vinck Bucharest Januar 2009. Council directive 96/48/EC of 23 July on the interoperability of the trans-European highspeed rail system. Directive 2001/16/EC of the European Parliament and of the council of 19 March 2001 on the interoperability of the conventional rail system. Directive 2004/50/EC of the European Parliament and of the council of 29 April 2004 amending Council Directive 96/48/EC on the interoperability of the trans-European highspeed rail system and directive 2001/16/EC of the European Parliament and of the Council on the interoperability of the trans-European conventional rail system. Letter of intent ERTMS deployment on Rotterdam Genova Corridor March 2006. Declaration of Ministers on rail freight corridors June 2010. Memorandum of Understanding (MOU) between the European Commission and the European Railway Associations (CER-UIC-UNIFE-EIM-GSM-R Industry Group - ERFA) concerning the strengthening of co-operation for speeding up the deployment of ERTMS July 2008. Memorandum of Understanding (MOU) between the European Commission and the European Railway Associations (CER-UIC-UNIFE-EIM) establishing the basic principles for the definition of an EU deployment strategy for ERTMS March 2005. Memorandum of Understanding (MOU). Schaffung einer internationalen Arbeitsgruppe zur Analyse der Probleme im Nord- SdGterverkehrskorridor und zur Lsung derselben Januar 2003. Corridors A Rotterdam Genova Annual Reports 2009. Corridors C Antwerpen/Basel/Lyon Annual Reports 2009. INTEROPERABILIT PRODOTTI EUROBALISE Autore/i: Claudio Rossi, Matteo Memoli, Marco Torassa e Pierluigi Pieraccini Capitolo: SICUREZZA, SEGNALAMENTO E NORMATIVA DI ESERCIZIO Rivista: Mese: Giugno Anno: 2005 Pagina: 21. LE NORME DESERCIZIO PER LERTMS Autore/i: Michele Mario Elia e Paolo Genovesi Capitolo: EDITORIALE Rivista: Mese: Aprile Anno: 2005. I collegamento dati tramite il GSM-R per il sistema ERTMS - La codifica HDLC rappresenta una scelta appropriata Autore/i: Coraiola A. Capitolo: IMPIANTI DI SEGNALA-MENTO E CONTROLLO DELLA CIRCOLAZIONE - COMPONENTI Rivista: Mese: Novembre Anno: 2004 Pagina: 947. ERTMS: iI nuovo sistema europeo di controllo/comando per la supervisione del distanziamento treni Autore/i: Carganico C. - Filippini M. - Poggio A. Capitolo: IMPIANTI DI SEGNALAMENTO E CONTROLLO DELLA CIRCOLAZIONE - COMPONENTI Rivista: Mese: Gennaio Febbraio Anno: 1999 Pagina: 3.

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Application of new materials, concepts and technologies

iCTi2010, Fortes & Pereira (eds.) 2010, ISBN 978-972-8692-57-5

Measuring Asphalt-Aggregate Bond Strength Under Different ConditionsH. Bahia, R. Moraes & R. VelsquezDepartment of Civil and Environmental Engineering, University of Wisconsin-Madison, United States hubahia@facstaff.wisc.edu bringel@wisc.edu ravelasquez@wisc.edu

ABSTRACT: Moisture damage in pavements can be defined as the loss of stiffness and strength in the asphalt mixture due to a combination of mechanical loading and moisture intrusion. There are three mechanisms by which moisture degrades mixture performance: loss of cohesion within the asphalt, adhesive failure between aggregate and asphalt, and degradation of the aggregate. The aggregate mineralogy, texture and porosity play a major role in the bond strength development. Furthermore, asphalt composition affects the bond strength since variation in concentrations of asphaltenes and maltenes can create different adhesion with the mineral surface. The purpose of this paper is to investigate the mechanisms by which moisture can affect the bond between asphalt and aggregates. The loss of bond strength due to moisture conditioning was evaluated by means of the newly developed Bitumen Bond Strength Test (BBS). An experimental matrix, which included different binders, modifications, and aggregate types, to account for different chemical and physical conditions in the aggregate-asphalt interface, was completed in this study. The results indicate that the bond strength of asphalt-aggregate systems is highly dependent on modification techniques and moisture exposure time. Polymers are found to improve the adhesion between the asphalt and aggregate as well as the cohesion within the binder. KEY WORDS: Moisture Damage, Stripping, Cohesion, Adhesion, Asphalt Composition, Bitumen Bond Strength Test (BBS). 1. INTRODUCTION In asphalt mixtures, moisture damage is defined as the loss of stiffness and strength due to moisture exposure under mechanical loading. Moisture damage reduces asphalt pavement integrity by accelerating distresses such as bleeding, cracking, rutting and raveling (Hicks et al., 2003). It is recognized that resistance of asphalt pavements to distresses depends on the mechanics of the bonding at the aggregate-binder interface, which could be highly affected by moisture conditions. There are three mechanisms by which moisture degrades an asphalt mixture: (a) loss of cohesion within the asphalt mastic, (b) failure of the adhesive bond between aggregate and asphalt (i.e., stripping), and (c) degradation of the aggregate (Copeland et al., 2007). The loss of cohesion occurs when water interacts with the asphalt binder resulting in a reduction in material integrity (Hicks et al., 2003). The loss of adhesion happens when water

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penetrates the interface between asphalt binder and aggregate. If the bond between the asphalt binder and the aggregate surface is sufficient, failure will occur within the asphalt binder. However, if poor bond exists, failure will happen between the asphalt and the aggregate interface (Kanitpong and Bahia, 2003). Stripping occurs when failure of the interface between the asphalt and the aggregate happens due to the presence of moisture. Water can cause stripping in different ways, such as spontaneous emulsification, displacement, detachment, pore pressure, hydraulic scouring, and osmosis (Aksoy et al., 2005). In this paper, the reduction in the asphalt-aggregate bond strength due to moisture after different conditioning times was experimentally investigated by means of the Bitumen Bond Strength (BBS). Different base binders, modifications, and aggregate types were used to account for a broad range of chemical and physical conditions of the asphalt-aggregate interface. 2. LITERATURE REVIEW 2.1. Asphalt-Aggregate Adhesion Mechanisms Most likely a combination of mechanisms occurs synergistically to produce adhesion. The three main mechanisms related to adhesion between asphalt binder and aggregate are physical, chemical, and mechanical interactions (Bhasin, 2006). The theories that fundamentally explain the adhesive bond between asphalt binder and aggregates are: mechanical theory, chemical theory, weak boundary theory, and thermodynamic theory (Kanitpong and Bahia, 2003; Terrel and Shute, 1989). The mechanical theory indicates that bonding of aggregate-binder is affected by physical properties of the aggregate such as porosity, texture, and surface area. The chemical theory suggests that adhesion depends on the pH and the functional groups of both the asphalt binder and aggregate. The weak boundary theory suggests that rupture always occurs at the weakest link of the asphalt-aggregate interface. Finally, the thermodynamic theory studies the attraction between aggregate-asphaltwater due to the difference in surface tension. These theories and associated mechanisms are not exclusively independent and many researchers agree that a combination of mechanisms could take place and result in weakening the asphalt mixture. What has been identified as a major challenge is a system that can effectively measure bond strength and evaluate effect of moisture exposure on its level. 2.2. Factors Influencing Adhesive Bond Between Asphalt and Aggregate 2.2.1. Effect of Asphalt Binder Characteristics Previous research has identified viscosity, chemical composition, film thickness and surface energy of asphalt binder as major factors affecting the adhesion of aggregate-asphalt systems. (Kanitpong and Bahia, 2003; Bahia et al., 2007). It has been reported that asphalt binder with higher viscosity has higher resistance to displacement by water than those with lower viscosity (Thelen, 1958). Also, higher concentration of polar compounds in high viscosity binders leads to better wetting within the asphalt-aggregate interface. The chemical characteristics of asphalt vary significantly with the crude oil source used in its production. Petersen et al. (1982) ranked various asphalt functional groups and identified that asphalts containing compounds such as carboxylic acids and sulfoxides have higher water absorption. However, asphalts with these compounds are easily removed from the aggregate

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surface by water. He observed that asphalt binders containing ketones and nitrogen are the least susceptibility to moisture damage. In terms of geometry, samples with thicker asphalt film tend to have cohesive failure after moisture conditioning. On the other hand, specimens with thinner asphalt film have adhesive failure (Kanitpong and Bahia, 2003). With respect to surface energy, according to the thermodynamic theory of asphaltaggregate adhesion, low values of this fundamental property for the asphalt is preferable to provide better wetting. 2.2.2. Effect of Aggregate Characteristics The characteristics of the aggregate play a major role in ensuring good adhesion. Size and shape of aggregate, pore volume and size, surface area, chemical constituents at the surface, acidity and alkalinity, adsorption size surface density, and surface charge or polarity are some of the widely cited characteristics in the literature. Aggregates are commonly classified as either hydrophilic or hydrophobic with regard to their affinity to water (Bhasin, 2006; Kanitpong and Bahia, 2003; Tarrar and Wagh, 1992). Hydrophilic aggregates are considered to be acidic due to their high content of silica. They have better affinity for water than asphalt binder. Hydrophobic aggregates, on the other hand, are considered to be chemically basic, with low silica content. They tend to have greater affinity for asphalt than water. In general, hydrophobic aggregate have higher resistance to stripping (i.e., adhesive failure) than hydrophilic aggregates. For example, limestone is classified as hydrophobic aggregate and granite is considered as hydrophilic. It is important to note that the level of basic or acidic condition of the limestone and granite aggregates may vary according to their chemical composition. Physical characteristics of aggregate surface such as roughness, porosity, dust coating and surface moisture also affect adhesion in asphalt-aggregate systems. For example, rough surfaces and therefore larger contact area are preferred for better adhesive bond. Furthermore, some porosity is desirable to provide mechanical interlock. Aggregates that have large pores on their exposed surfaces, such as limestone, appear to show stronger bonds with asphalt than aggregates that have smaller or fewer pores on the surface (e.g., granite) (Kanitpong and Bahia, 2003; Tarrer and Wagh, 1992). Moisture and dust can significantly reduce the bond strength of aggregate-asphalt systems. Dust has the tendency to trap air and cause improper bond. When moisture is present in the pores of the aggregate surface, asphalt is prevented from contacting aggregate surface for good bonding. 4. MATERIALS AND TESTING PROCEDURE 4.1. Materials Two types of aggregates which are known to have different moisture sensitivity were selected: limestone and granite. Two commonly used asphalt binders were selected in this study: Flint Hills (FH) PG 64-22 and CRM PG 58-28. Also, four modified asphalt binders were prepared: FH64-22+1%PPA (modified with 1% by weight of polyphosphoric acid), FH64-22+0.7%Elvaloy (modified with 0.7% by weight of Elvaloy), CRM58-28+1%PPA (modified with 1% by weight of PPA) and CRM58-28+2%LSBS (modified with 2% by weight of Linear Styrene Butadiene Styrene). For conditioning media, tap water is used to investigate the effects of conditioning media on the adhesion between asphalt and aggregate.

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4.2. Bitumen Bond Strength Test (BBS) The challenge to quantitatively evaluate the adhesive bond between asphalt and aggregate is to identify a test which is simple, quick and repeatable for evaluating adhesion properties of asphalt-aggregate systems. Furthermore, no method is included in the Superpave binder specifications to evaluate adhesive characteristics of asphalt binders (Copeland et al., 1998). Youtcheff and Aurilio (1997) used the Pneumatic Adhesion Tensile Testing Instrument (PATTI), originally developed for the coating industry, to measure the moisture susceptibility of asphalt binders. In this study, the Bitumen Bond Strength Test (BBS), which is a significantly modified version of the original PATTI (Meng, 2010), was used to evaluate the asphalt-aggregate bond strength. The main components of the BBS equipment are: pressure hose, portable pneumatic adhesion tester, piston, reaction plate and metal pull-out stub (Figure 1). Before running a test, the piston is placed over the pull-out stub and the reaction plate screwed on it. Then, compressed air is introduced through the pressure hose to the piston. An upward pulling force on the specimen is applied by the pull-out stub. During the test, failure occurs when the applied pressure exceeds the cohesive strength of the asphalt binder or the adhesive strength of the binder-aggregate interface. The pressure at failure is recorded and the pull-off tensile strength (POTS) is calculated by:

POTS =

(BP Ag ) CA ps

(1)

where: Ag = contact area of gasket with reaction plate (mm2); BP = burst pressure (kPa); Aps = area of pull stub (mm2); C = piston constant. The pull-out stub has a rough surface that can prevent asphalt debonding from the stub surface by providing mechanical interlock and larger contact area between the asphalt binder and stub. The pull-out stub in the BBS test has a diameter of 20 mm with a surrounding edge, used to control film thickness. The stub edge has a thickness of 800 m. 4.2.1. Aggregate Sample Preparation Aggregate plates were cut with similar thickness and parallel top and bottom surfaces. After cutting and lapping, aggregates plates are immersed in distilled water in an ultrasonic cleaner for 60 minutes at 60C to remove any residue from the cutting process and neutralize the surface of aggregate to its original condition. It should be mentioned that the lapping is done to provide a control on the roughness of the surface. 4.2.2. Asphalt Sample Preparation The aggregate surface and pull-out stubs are degreased with acetone to remove moisture and dust which could affect adhesion. After cleaning with acetone, the pull-out stubs and the aggregate plates are heated in the oven at 65C for a minimum of 30 minutes to remove absorbed water on the aggregate surface and provide a better bond between the asphalt binder and the aggregate. The asphalt binders are heated in oven at 150C. The stubs are removed from the oven and an asphalt binder sample is placed immediately on the surface of the stub for approximately 10 seconds. Then, the aggregate plate is removed from the oven and the

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stub with the asphalt sample is pressed into the aggregate surface firmly until the stub reaches the surface and no excess of asphalt binder is observed to be flowing. The stubs need to be pushed down as straight as possible and twisting needs to be avoided to reduce the formation of trap air bubbles inside the sample and to minimize stresses. Before testing, dry samples are left at room temperature for 24 hours. For wet conditioning, samples are first left at room temperature for 1 hour to allow for the aggregatebinder-stub system to reach a stable temperature. Then, samples are submerged into a water tank at 40C for the specified conditioning time. After conditioning time is completed, samples are kept at room temperature for 1 hour before testing.

Figure 1: Bitumen Bond Strength Test (BBS) 4.2.3. Testing Procedure The BBS testing procedure can be summarized with the following steps: Before testing, air supply and pressure hose connection should be checked. Set the rate of loading to 100 psi/s. Measure sample temperature using a thermometer before starting the test. Place circular spacer under the piston to make sure that the pull-off system is straight and that eccentricity of the stub is minimized. Carefully place the piston around the stubs and resting on the spacers not to disturb the stub or to induce unnecessary strain in the sample. Screw the reaction plate into the stub until the pressure plate just touches the piston. Apply pressure at specified rate.

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After testing, the maximum pull-off tension is recorded and the failure type is observed. If more than 50% of the aggregate surface is exposed, then failure is considered to be adhesive; otherwise, it is a cohesive failure.

5. ANALYSIS OF RESULTS 5.1. Effect of Conditioning Time In this study, samples were conditioned in tap water for 0, 6, 24, 48, and 96 hours. The effect of conditioning time on the pull-off strength of the asphalt-aggregate systems tested can be observed in Figure 2.

Figure 2: Influence of conditioning time on the pull-off tensile strength (POTS) for different asphalt-aggregate systems The average pull-off strength was calculated from four replicates. The conditioning of specimens in water caused a significant reduction in the pull-off strength and a change in the failure mode from cohesive to adhesive type (see Table 1), regardless of the selected asphalt binder or aggregate. The change in failure mode is expected since water penetrates through the aggregate, which is a porous material, and hence weakens the bond at the interface

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(Kanitpong and Bahia, 2003). The longer the conditioning time in water, the weaker the interface bond and the lower the pull-off strength value observed. 5.2. Effect of Asphalt Modification The effects of modification of asphalt are clearly indicated by the BBS testing results. For example, Figure 2 shows that the modified FH64-22 binders have higher dry average pull-off tensile strength in comparison to the neat binder for both granite and limestone aggregates. The asphalts modified with PPA show less susceptibility to moisture conditioning in comparison to neat asphalts. Note that the effect of PPA is better in granite than in limestone aggregates. Asphalt binder modified with elvaloy also show moisture resistance improvements for the granite case compared to the neat asphalt. However, for the limestone case, no significant difference between FH64-22 neat and FH64-22+Elvaloy were observed. Failure mechanisms are also affected by modification type. Table 1 indicates that failure type (i.e., cohesive and adhesive failure) changes according to modification, aggregate type and conditioning time. Note that all unconditioned (i.e. dry) samples showed cohesive failure (i.e., failure within asphalt). On the other hand, adhesive failure (i.e., between aggregate and binder) was observed for some conditioned specimens. The results show that the failure type after 6 hours of conditioning time for the FH 64-22 asphalt changes from adhesive to cohesive when PPA is used as modification. These observations indicate that PPA improves the bond of the interface between the asphalt and granite. All samples containing PPA have cohesive failure, which indicates that the bond at the aggregate-binder interface is greater than the cohesive strength of the binder at the specified testing conditions.

5.3. Effect of Aggregate Type The nature and chemical characteristics of aggregates greatly affect bond strength and failure mechanisms of asphalt-aggregate systems as indicated by Table 1. On both limestone and granite surfaces the failure mode changed after moisture exposure, showing that the nature of the aggregate greatly affects adhesion. It can be seen that for all limestone samples, the failure type was cohesive, which indicates that the adhesive bond in the asphalt-aggregate interface is larger than the cohesive strength of the binders. Also, Figure 2 indicates that limestone aggregates have higher adhesive bond to asphalt than granite aggregates, and thus more resistance to adhesive failure. The pull-off tensile strength obtained from BBS tests performed is highly influenced by the cleanness of the surface of the aggregate plate. Inconsistent and unexpected results for some of the samples conditioned at 48 and 96 hours were obtained when the aggregate plate used was different than the plate used for the 0, 6, and 24 hours tests. It appears that slight changes of the aggregate surface can greatly affect the magnitude of the pull-off tensile strength. Therefore, it is always important to perform moisture susceptibility experiments using the aggregates from the same source and to be consistent in sample preparation.

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Table 1: Influence of conditioning time, modification, and aggregate type in the failure mode. Asphalt Binder Type *CT (hr) Dry 6 24 48 96 Dry 6 24 48 96 Dry 6 24 48 96 Dry 6 24 48 96 Dry 6 24 48 96 Dry 6 24 48 96 Failure Type Granite Limestone Cohesion Cohesion Adhesion Cohesion Adhesion Cohesion 50%A -50%C 50%A -50%C Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Adhesion Cohesion Cohesion 50%A -50%C Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Adhesion Cohesion Adhesion Adhesion Cohesion Cohesion Adhesion Cohesion Adhesion Cohesion 50%A -50%C Adhesion Adhesion Adhesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion Cohesion

FH64-22 neat

FH64-22+Elvaloy

FH6422+1%PPA

CRM 58-28 neat

CRM 58-28+2%SBS

CRM58-28+1%PPA

*Conditioning Time (CT)

6. CONCLUSIONS This paper shows promising results regarding characterization of asphalt-aggregate bond under different conditions by means of a simple to perform test. The results and analysis lead to the following conclusions: The Bitumen Bond Strength (BBS) test can effective measure the effects of conditioning time and modification on the bond strength of asphalt-aggregate systems.

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The pull-off tensile strength decreases when samples are conditioned in water, regardless of the selected asphalt binder or aggregate type. Bond measurements for the dry samples have lower coefficient of variation than for the samples tested after water conditioning. Conditioning of specimens in water causes not only loss of pull-off tensile strength but also a change in the failure mechanism. In absence of water, failure usually happens within the asphalt (i.e. cohesive failure). After water conditioning, the failure changes from total cohesive to adhesive failure. It is observed that the bonding between asphalt and aggregate under wet conditions is highly dependent on binder modification type and conditioning time. Polymers are found to improve the adhesion between the asphalt and aggregate as well as the cohesion within the binder. Polyphosphoric Acid (PPA) significantly improves the moisture resistance of asphaltaggregate systems tested in this study. The effect is especially noticed for granite or acidic aggregates. All samples containing PPA have a cohesive failure, which indicates that the bond at the aggregate-binder interface is greater than the cohesive strength of the binder.

REFERENCES Aksoy, A., Samlioglu, K., Tayfur, S. and Ozen, H., 2005. Effects of Various Additives on the Moisture Damage Sensitivity of Asphalt Mixtures. Construction and Building Materials, vol. 19, pp. 1118. Bahia, H. U., Hanz, A., Kanitpong, K., and Wen, H., 2007. Testing Methods to Determine Aggregate/Asphalt Adhesion Properties and Potential Moisture Damage. WHRP 07-02, Wisconsin Highway Research Program, Madison, Wisconsin. Bhasin, A., 2006. Development of Methods to Quantify Bitumen-Aggregate Adhesion and Loss of Adhesion Due to Water. Ph.D. Dissertaton, Texas A&M University, College Station, Texas. Copeland, A. R., Youtcheff, J. and Shenoy, A., 2007. Moisture Sensitivity of Modified Asphalt Binders-Factors Influencing Bond Strength. Transportation Research Record: Journal of the Transportation Research Board, No. 1998, Transportation Research Board of the National Academies, Washington, D.C., pp. 1828. Hicks, R. G., Leahy, R. B., Cook, M., Moulthrop, J. S. and Button, J., 2003. Road Map for Mitigating National Moisture Sensitivity Concerns in Hot-Mix Pavements. Proceedings of the National Seminar on Moisture Sensitivity of Asphalt Pavements, San Diego, CA, pp. 331. Kanitpong, K. and Bahia, H. U., 2003. Role of Adhesion and Thin Film Tackiness of Asphalt Binders in Moisture Damage of HMA. Asphalt Paving Technology, vol. 72, pp. 502-528. Petersen, J. C., Plancher, H., Ensley, E. k., Venable, R. L., and Miyake, G., 1982. Chemistry of Asphalt-Aggregate Interaction: Relationship with Pavement Moisture-Damage Prediction Test. Transportation Research Record, No. 843, TRB, National Research Council, Washington D.C. , p.95-104. Meng, J., 2010. Affinity of Asphalt to Mineral Aggregate: Pull-off Test Evaluation, MS Thesis, University of Wisconsin, Madison. Santagata, F. A., Cardone, F., Canestrari, F. and Bahia, H. U., 2009. Modified PATTI Test for the Characterization of Adhesion and Cohesion Properties of Asphalt Binders. Proceedings of the 6th International Conference on Maintenance and Rehabilitation of Pavements and Technological Control (MAIREPAV6), Torino, Italy.23

Tarrer, A. R., and Wagh, V. P., 1992. The Effect of the Physical and Chemical Characteristics of the Aggregate on Bonding. Strategic Highway Research Program Report SHRP-A/UIR91-507, Washington, D.C. Terrel, R. L., and Shute, J. W., 1989. Summary Report on Water Sensitivity. SHRP-A/IR-89003, Strategic Highway Program, Washington, D.C. Thelen, E., 1958. Surface Energy and Adhesion Properties in Asphalt-Aggregate Systems. HRB Bulletin 192, Highway Research Board, Washington D.C., pp. 63-74. Youtcheff, J., and Aurilio, V., 1997. Moisture Sensitivity of Asphalt Binders: Evaluation and Modeling of the Pneumatic Adehsion Test Results. 42nd Annual Conference of Canadian Technical Asphalt Association, Canada, pp. 180-200.

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iCTi2010, Fortes & Pereira (eds.) 2010, ISBN 978-972-8692-57-5

Design and Performance Analysis of Foamed Asphalt Treated MixturesA. Marradi, G. Ridondelli & U. PinoriDepartment of Civil Engineering, University of Pisa, Italy a.marradi@ing.unipi.it, giacomo.ridondelli@ing.unipi.it, umberto.pinori@ing.unipi.it

ABSTRACT: The need to apply in situ cold recycling techniques for flexible pavement rehabilitation arises in response to economic, environmental and operational issues. The constant search for more efficient solutions to address these issues must be underpinned by in-depth studies which not only allow achievement of satisfactory performance but also ensures proper definition of the mechanical parameters to be adopted in the pavement design. This paper focuses on the technique of recycling an existing asphalt concrete by means of foamed bitumen with special emphasis on the dynamic performance of mixtures thus obtained. In addition to the classic determinations of resistance and deformation, stiffness and fatigue resistance tests were performed to define the behaviour of the material from the point of view of mechanistic design. Finally, as a result of fatigue tests performed, the material was assigned a stiffness degradation induced by repeated dynamic loads, based on which it is possible to outline a method for a more reliable and realistic estimate of the useful life of pavements. KEY WORDS: Foamed asphalt treated mixture, RAP, Mix design, Stiffness modulus, Resistance to fatigue, Recycling. 1. INTRODUCTION In road construction, the term recycling defines the re-use of materials obtained from a distressed pavement which are then utilized to construct new pavement layers, after demolition or milling and subsequent treatment with the possible addition of suitable binders. Recourse to such recovery operations offers many advantages. First of all, it reduces both the exploitation of quarries for extraction of virgin aggregates as well as the areas intended for disposal of material removed. In particular, on-site cold recycling procedures have generated great interest in the scientific and technical community and, at the same time, among the construction companies. In these techniques, bitumen is the most widely used binder, both as foam and as emulsion and the addition of cement has the primary purpose of obtaining the necessary compromise between resistance to deformation and flexibility. Recovery of the reclaimed asphalt pavement (RAP) can be total and immediate when carried out on-site, making it possible to eliminate the logistical problems involved in transportation towards fixed plants or landfills. In addition, the amount of carbon dioxide and other pollutants emitted during mixing with the bituminous binder is practically negligible. Thence, there is also an unquestionable economic advantage, provided that the recycling technique is mature enough to guarantee durability and resistance levels comparable to those of classic solutions. It is necessary to increase technical and scientific knowledge on25

alternative materials, defining the mechanical behaviour and any critical or idiosyncratic characteristic that affect or encourage their use in specific applications. 2. EXPERIMENTAL PROGRAM In the framework of the above considerations, the present study focuses on in situ recycling of pavements with the foamed bitumen technique, determining by laboratory tests the actual response to dynamic loads, so as to assess dynamic stiffness and fatigue resistance. Both of these parameters are necessary to allow an experimentally-based mechanistic design method for a pavement containing recycled materials. The data obtained from fatigue tests were assessed through further analysis and interpretations, in order to define and explain the good durability shown on sites where the recycled mix was adopted to construct the pavement base layer. The experimental program (Table 1) is composed of four types of tests to be conducted on samples compacted by means of a gyratory compactor using the parameters shown in Table 3. The quantities of CEM II/B-M 32.5 Portland cement (UNI EN 197-1/2001), bitumen and water to prepare specimens were respectively 2%, 3% and 5%, that is the optimal solution obtained by the mix design procedure. Table 1: Experimental program Test type Indirect diametrical tensile strength Resistance loss after water immersion Stiffness modulus Resistance to fatigue 3. CHARACTERIZATION OF RAW MATERIALS 3.1. Aggregate The quantity of material necessary for mix design procedures and further laboratory tests was collected by milling a portion of the pavement assessed as being in need of restoration operations. Generally, milling cannot separate all the bound material. There remain agglomerates of aggregates that produce a fairly marked difference between the grading curve of the RAP as is and the curve obtained after extraction of the bituminous binder. In this respect it can be said that the as is curve, taking into account the incidence of undivided agglomerates formed by residual bituminous bound particles, should be considered when it is necessary to evaluate quantity of surface to be coated with bitumen and the effective presence of fine available for dispersion of the binder (mix design phase). In contrast, the after extraction curve obtained after solvent action is needed in order to verify, in qc/qa of mixtures after construction, the respondency of grain size distribution to the curve obtained from the mix design, which must in this case be considered as after extraction. Size distribution detected before extraction and bitumen content of RAP are shown in Figure 1. 3 Curing time (days) 14 28

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100 90 80

Bitumen content referred to the mass of the mixture (%): 3.9 Bitumen content referred to the mass of the aggregate (%): 4.1

Passage ratio (%)

70 60 50 40 30 20 10 0 0.01 0.1 1 10 100

Sieve size (mm)

Figure 1: Grain size distribution and composition of RAP 3.2. Asphalt binder The binder used in the foaming process is bitumen 70/100 Azalt produced and indicated as suitable for this purpose by Total Italia. Its characteristics are specified in Table 2. For what concerns the quality of foamed bitumen, the key parameters are expansion ratio and half-life: the first one indicates the viscosity of the foam and is calculated as the ratio between the maximum volume of foam and the original volume of bitumen; the second one consists of the time during which the volume of foam changes from maximum to its half and measures stability of the foam indicating its speed of collapse. Table 2: Characteristics of bitumen used in the foaming process Penetration (dmm) 82 Softening point (C) 49 Fraas breaking point (C) -9 Expansion ratio* 18 Half-life time* (sec) 68

*temperature: 170C; water in the foaming process: 3.0% of the bitumen weight

4. SPECIMEN COMPACTION AND CONDITIONING 4.1. Compaction After producing the foam bitumen using the Wirtgen WLB10 machine, designed to reproduce the normal functioning of the production equipment installed on recycling machines, samples were compacted with the gyratory compactor, adopting the standard parameters shown in Table 3. Table 3: Gyratory compaction parameters Vertical pressure (kPa) 600 3 4.2. Curing In general, specimens must be subjected to a conventional process of curing to simulate the departure of the water and the strengthening of the material that can be observed in the27

Gyration angle () 1.25 0.02

Gyration speed (rpm) 30

Specimen diameter (mm) 150

Number of gyrations (#) 180

Specimen weight (g) 4500

pavement. For what concerns curing time, Castedo et al. (1983) reported that foamed asphalt strengths increase with curing time, particularly from 1 to 3 days. Most of the previous researches adopted the laboratory curing procedure proposed by Bowering (1970), that is 3 days oven curing at 60C (Kim et al., 2006). This procedure allows to obtain a moisture content stabilizing at about 0 to 4 per cent, which represents the driest state achievable in the field. In spite of this, concerns have been expressed over the binder ageing which may occur at a curing temperature of 60C. Moreover, since this temperature is above that of the softening point of common road-grade bitumens, changes in bitumen dispersion within the mix are possible during curing (Muthen, 1999): 49C is really the softening point value measured for bitumen used in the present study (Table 2). On the other hand, some Authors recommended a temperature of 40C for 1-day intermediate curing and 3-day long-term curing (Kim et al., 2006): the Italian most common specifications align themselves to this position. That considered, curing times of 3, 14 and 28 days at a temperature of 40C were adopted. Some researches compare the effect of the composite curing 24 h @ ambient in mould, 72 h @40C to a nominal field cure period from 1 (Kekwick, 2005) to 6 months (AIPCR, 2003). 5. LABORATORY TESTS 5.1. Indirect diametrical tensile strength test IDTS tests were carried out at 25C adopting the test equipment described in UNI EN 1269723. CTI (Indirect Tensile Coefficient) is a stiffness parameter that appears in the main Italian specifications (ANAS, Autostrade) and is given by the following equation:CTI =

D IDTS2 Dc

where D = diameter of the specimen, Dc = breaking deformation. The results of tests after 3day curing and the above mentioned reference values are summarized in Table 4. Table 4: IDTS tests results IDTS (N/mm2) CTI (N/mm2) Mean Standard deviation Reference values 0.32 0.02 0.32 0.55** 76 3 50** IDTS* (N/mm2) 0.28 0.01 CTI* (N/mm2) 71 1 IDTS/IDTS 0.88 0.70***

*before testing, specimens were kept at the temperature of 25 C and at the pressure of 50 mmHg for 1 hour **ANAS (2008) specifications ***Autostrade (2004) specifications

5.2. Stiffness moduli Since there is currently no specific standard for determination of the dynamic stiffness modulus of foamed asphalt treated mixtures, it was considered appropriate to adopt the same test equipment currently used for asphalt concrete and described by UNI EN 12697-26

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(indirect tensile configuration, IT-CY). However, in the present test, specimen height was greater than the maximum stated in the above-mentioned standard (75 mm). The procedure involves the application of IT-CY indirect diametrical tensile stress on cylindrical specimens compacted using the gyratory compactor, adopting the following parameters: rise-time: 0.075, 0.125 and 0.200 s; pulse repetition period: 3.000 s, temperature: 20C. The evolution of stiffness with respect to frequency of applied load was evaluated using three different rise-time values. Furthermore, a series of tests was undertaken in which the stress induced was increased each time, in order to investigate the behaviour of the material in respect of the magnitude of applied load and thus to detect any non-linear behaviour. Care was taken to maintain the strain measured on the horizontal diameter in the range of 40 (that is approximately a value of 80 at the central point of the specimen), as this threshold is recognized as optimal by UNI EN 12697-26 on asphalt concrete and, with regard to cement-bound mixtures, it does not cause stress-cracking that can compromise test results (Lancieri et al., 2009), as proved by results contained in 5.2.2. Furthermore, previous studies showed that this strain level should not be exceeded to reduce the fatigue risk when the material is used as base layer on heavy trafficked roads (Losa et al., 2009). The Poissons ratio of foamed asphalt treated mixtures varies with respect to bitumen and cement content, as stated by Berthelot et al. (2007): with regard to a stabilized granular base, the tests conducted adopting a load frequency equal to 1 Hz showed values between 0.18 (when 2% of foamed asphalt and 1.5% of cement were added) and 0.40 (when 3% of foamed asphalt was added). In the present study, a value of 0.30 was assigned, accordingly to the most common values reported in the technical literature. 5.2.1. Curing time and frequency of load application The stiffness modulus value obtained for the rise-time of 0.200 s, corresponding to a frequency of about 1 Hz, aligns itself to the prescription (1700 MPa) required by Autostrade (2004) specifications for similar values of frequency and temperature. Table 5: Values of stiffness modulus@0.200s for three curing times Mean (MPa) Standard deviation (MPa) 3-day curing time 1711 109 14-day curing time 3234 211 28-day curing time 3576 248

It is also noticeable that the first phase of the curing period was characterized by a much stronger growth of stiffness in comparison to the subsequent period. This trend may be related both to the type of curing (at 40C) and to the curing rate of cement, which appears to develop mainly during the first days of climatic chamber curing. As far as the frequency domain is concerned, a viscous behaviour was observed: an increase in stiffness with decreasing rise-time (ie a frequency raise) can be seen, as shown in Table 6. Table 6: Stiffness modulus increases as percentages of values@0.200 s Rise-time (s) 0.200 0.125 0.075 3-day curing time 1711 Mpa +9.1% +19.8% 14-day curing time 3234 MPa +9.0% +18.8% 28-day curing time 3576 MPa +8.9% +17.8%

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5.2.2. Curing time and peak load values A series of IT-CY stiffness modulus tests were conducted, increasing each time the compression load values on the vertical diameter, in order to verify the assertion that some Authors (Asphalt Academy, 2009) attribute these mixtures a stress-dependant behaviour, because the individual bitumen droplets are not linked and the coarser aggregate particles remain uncoated, maintaining the granular characteristics of the parent material. The stiffness moduli were determined by imposing horizontal diametral strain values between 30 and 50 and a rise-time of 0.200 s. For 3-day and 28-day curing time, the corresponding indirect tensile stress applied was approximately up to 30% of the IDTS value measured and equal to 0.32 N/mm2 (for 3-day curing, see Table 4) and 0.55 N/mm2 (for 28day curing). The results obtained for different rise-times and curing periods showed no stressdependent behavior for strain up to 50 , as indicated in Figure 2.4500

3-day curing

Stiffnessmodulus(MPa)

4000 3500 3000 2500 2000 1500 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20

14-day curing 28-day curing Rise time: 0.075 s Rise time: 0.125 s Rise time: 0.200 s

Peak stress(MPa)

1 Peak load 2 Pulse repetition period 3 Rise-time

Figure 2: Stiffness modulus vs. peak stress diagram (left) and form of load pulse, showing the rise-time and peak load (right) 5.3. Resistance to fatigue With regard to the foamed asphalt treated mixtures, the bitumen and cement must provide a satisfactory compromise in terms of flexibility (resistance to fatigue) and stiffness (resistance to deformation). Resistance to fatigue tests were therefore performed on cylindrical specimens, as described in the UNI EN 12697-24 standard designed for asphalt concrete. A good interpolation of the results given in terms of 0-N (initial strain at the central point of the specimen- number of load cycles to failure of specimens) can be obtained with the curve shown in Figure 3.1000

Initial deformation ()

100

y = 656.4x -0.1497 R = 0.91

10 1000

10000

100000

1000000

Number of cycles

Figure 3: Resistance to fatigue test results

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At strain levels lower than 80 , the admissible number of cycles is greater than 106 and the integrity of the specimen didnt reduce at all; this strain value can be considered a safe value with regard to the fatigue risk. As stated in a previous study (Losa et al., 2009), a fatigue relationship seems to be identifiable for such low strain levels, but it should not be reliable being the regression line quite horizontal and its correlation coefficient too low. These results align themselves with considerations expressed by Multhen (1999), who reported that foamed asphalt mixes, having mechanical characteristics that fall between those of a granular structure and those of a cemented structure, show fatigue characteristics inferior to those of hot-mix asphalt materials, as stated by Bissada (1997) and Little et al. (1983). However, available experiences on trial sections currently under monitoring of University of Pisa for over 3 years (Marradi, 2007) confirm that once laid these recycled mixtures can perform significantly better than expected: this can be explained considering the on-site postcompacting effect produced by vehicular traffic (Montepara, 2008) and assuming the selfpreservation behaviour that arose during the laboratory tests and that is summarized below. 5.4. Resistance to fatigue and decay of stiffness: self-preservation of the foamed asphalt treated mixtures Horizontal deformation measured during fatigue tests allowed determination of the stiffness modulus with respect to the number of load cycles (n), according to the following relation contained in UNI EN 12697-26: F ( + 0.27 ) S = m zh where Sm = stiffness modulus (MPa), F = peak load (N), = Poissons ratio, z = horizontal diametrical strain (mm), h = specimen thickness (mm). Several specimens were tested, each subjected to a different stress level, namely a different value of initial deflection 0 ( 5.3). Expressing Sm as a percentage (%Sm0) of the initial value Sm0, for each specimen a %Sm0-n trend was obtained, as shown in Figure 4a. For each stress level the values can be interpolated with good accuracy using exponential laws, henceforth called decay curves (Figure 4b). With increasing number of load cycles, they showed a decrease in stiffness modulus, the Sm decrease becoming sharper with increasingly elevated values of applied stress, up to breaking point.100 90 80 70 60

100 90 80

50 40 30 20 10 0 100

Stress level 1 Stress level 2 Stress level 3 Stress level 4 Stress level 5 Stress level 6 Stress level 7 Stress level 8 Stress level 9 Stress level 101000 10000 100000 1000000

70

%Sm0

%Srm0

60 50 40 30 20 10 0 10 100 1000 10000 100000 Stress: 0.53 MPa Stress: 0.46 MPa Stress: 0.40 MPa Stress: 0.35 MPa

n

n

Figure 4: a) Stiffness measured; b) Decay curves parameterized as a function of stress level This behaviour of foamed asphalt treated mixtures was also observed during in situ surveys (Wirtgen GmbH, 2004): it was ascertained that after a phase of ageing, during which the dynamic modulus increases as the material cures and humidity decreases to equilibrium levels, two phases can subsequently be distinguished: first phase, when stiffness diminishes due to the effects of repeated traffic loads;

31

second phase, when material cracking results in a equivalent granular layer state. Asphalt Academy (2009) confirms this two-phase behaviour and suggest to adopt a model parameter (called Effective Long Term Stiffness) which serves as a relative indicator of the average long term in situ stiffness of a pavement layer, taking into account the decrease of stiffness owing to traffic related deterioration: a further development of this approach, consisting of decay curves application in design process, is proposed in the following paragraphs. 5.4.1. The first phase The above mentioned loss of stiffness has important consequences on the way a pavement containing a foamed asphalt treated layer behaves under traffic loads, as the part of the load taken by this layer decreases with respect to load repetition. That is to say, it can legitimately be underlined that laboratory testing through which the fatigue laws can be derived is performed in force control, ie maintaining a constant load applied: this mode of operation is conceptually well-founded, since it simulates the effect of an impulsive load (due to traffic) that does not vary during load repetitions. However, heterogeneous development of stiffness of the different materials that constitute the pavement layers may lead to a redistribution of tensions among such layers. For each layer that undergoes a decrease in stress level, others can be distinguished that tend to become overloaded. Normally, the decay in stiffness is not considered in design processes. This is correct as long as its magnitude is negligible or is of the same order of magnitude for all the materials that constitute the pavement: in such cases, there is no redistribution of tension. However, there are studies that attribute to unbound materials and to asphalt concrete a negligible drop of stiffness during the useful life of the pavement, while for cement bound mixtures this behaviour should be taken into account (Thgersen et al., 2004). Thus foamed asphalt treated mixtures show a self-preservation behaviour during the useful life of the pavement, since there is a decrease in stiffness and therefore also in stress level. The performance will consequently be better than that inferred on the basis of classical fatigue tests, during which, as mentioned, the load applied has a constant peak value. For design purposes, if the strain level is higher than 80 , that can be considered the safe value with regard to the fatigue risk ( 5.3), it seems more convenient to schematize the actual behaviour with regard to load repetitions on the basis of decay curves parameterized as a function of stress of the material (Figure 4b). Thus the first phase should be subdivided into several substages corresponding to gradually decreasing stress levels. This behaviour is in agreement with that described by Long (2001): the back-calculation of data from trial section subjected to Heavy Vehicle Simulator tests showed that the stiffness of the foamed bitumen treated material (containing 2% cement and 1.8% foamed bitumen) initially decreased rapidly, thereafter with a more gradual decrease to an equivalent granular state. The stiffness decrease was load dependent, and the damage exponent estimated taking into account the effective fatigue life, that is the number of load repetitions to reach the equivalent granular state, was found to be larger than the values typically assumed: it seems therefore very important to consider the effective stress induced by each type of traffic, to which a particular decay curve corresponds. 5.4.2. The second phase Once breaking has occurred, the IT-CY configuration is no longer adequate to estimate the stiffness modulus. Even if the material retains a certain portion of the internal bonds that formed part of its initial characterization, it becomes almost granular unbound.

32

Consequently, there is no possibility of applying the concept of indirect tensile taken as the result of a compression load by virtue of cohesion within the material conceived as continuous. It follows that stiffness modulus estimation in the post-breaking phase may reasonably lead to significantly higher values than those characterizing an unbound granular mix, but it requires a different type of test procedure (triaxial cell), as suggested by Jenkins et al. (2007) and described in UNI EN 13286-7. In this regard, the stiffness values reported in the technical literature for this second phase behaviour vary in the range 200-600 MPa (Asphalt Academy, 2009, Long, 2001 & Wirtgen GmbH, 2004). 6. CONCLUSIONS The present study was conducted on the RAP material from the demolition of a pavement to be recycled with the foamed bitumen process. Laboratory tests performed on specimens having the optimal composition defined by mix design procedure showed that the behaviour of the material was viscous-type, because the variation of 1 Hz in frequency of load application, when the frequency is relatively low as in the case of IT-CY tests, induces a variation in the stiffness modulus close to 10%. Furthermore, examination of the effects of accelerated aging time at 40 C on stiffness showed that these effects are sensitive as long as curing time does not exceed 14 days. Beyond this period, the gradient with which the resilient module increases is much less sharp, indicating that reactions involving cement are close to exhaustion: thence, 14day@40C is sufficient to obtain a long-term value of stiffness modulus. Fatigue tests performed adopting the IT-CY configuration made it possible to confirm 80 as a safe strain value with regard to the fatigue risk. Considering the lack of influence exerted by the magnitude of the load applied in stiffness modulus tests to induce strain in the range of the above-mentioned value, the stiffness modulus previously obtained can be considered significant in order to adopt a linear-elastic model in the design process of the pavement. For higher deformation values, experimental results suggested the need to go beyond the usual concepts linking stress, stiffness modulus and load repetition in order to achieve a more realistic schematization of the behaviour of the material. Applying a constant stress level to each specimen, an increase in deformation was noticed, a reduction in stiffness being observed with increasing loading cycles. Furthermore, the more intense was the peak load applied, the sharper was the effect observed. For each stress level at which the dynamic test was conducted, an exponential decay curve was found. This means that a foamed asphalt treated layer is characterized by a reduction in stiffness resulting from repeated traffic loads and consequently by a decrease in stress, differently to the other materials of the pavement, which accumulate more stress. So, implementation of the decay curves in pavement design procedures leads to values of damage affecting the foamed asphalt treated mixture that are generally lower than those obtained with the standard methods of mechanistic design. The definition of such a design procedure, together with the study of the constitutive law for strain level above 100 and the determination of the second phase dynamic modulus, which are expected to use appropriate triaxial cell tests, will be the object of the following work. REFERENCES AIPCR, Pavement recycling, Guidelines for in-place recycling with cement, in-place recycling with emulsion or foamed bitumen, hot mix recycling in plant, La Defence, Cedex, 2003.33

Asphalt Academy, Technical Guideline: Bitumen Stabilised Materials, TG 2, Pretoria, 2009. Berthelot, C., Podborochynski, D., Fair, J., Anthony, A., Brent Marjerison, B., Mechanisticclimatic characterization of foamed asphalt stabilized granular pavements in Saskatchewan, Paper prepared for presentation at the Characterization and Improvement of Soils and Materials Session of the 2007 Annual Conference of the Transportation Association of Canada, Saskatoon, Saskatchewan. Bissada, A. F., Structural response of foamed-asphalt-sand mixtures in hot environments, Asphalt materials and mixtures, Transportation Research Record 1115, Transportation Research Board, Washington, DC, 1987, pp. 134-149. Bowering, R. H., Properties and behaviours of foamed bitumen mixtures for road building. Proc., 5th ARRB Conf., Australian Road Research Board, Canberra, 6, 1970, 38-57. Castedo, F. L. H., Wood, L. E., Stabilization with foamed asphalt of aggregates commonly used in low-volume roads, Transportation Research Record 898, Transportation Research Board, Washington, D.C., 1983, 297-302. Jenkins, K. J., Long, F. M., Ebels, L. J., Foamed bitumen mixes = shear performance?, International journal of pavement engineering, Vol. 8, No. 2, 2007, pp. 85-98. Kekwick, S.V., Best practice bitumen emulsion and foamed bitumen materials laboratory processing, 24th Annual Southern African Transport Conference 2005. Kim, Y., Lee, H. D., Development of Mix Design Procedure for Cold In-Place Recycling with Foamed Asphalt, Journal of materials in civil engineering, ASCE, January/February 2006, 116-124. Lancieri, F., Marradi, A., Ridondelli, G., Preliminary investigation into the utilization of cupola slag as road construction material, Proceedings of the Sixth International Conference on Maintenance and Rehabilitation of Pavements and Technological Control, MAIREPAV6, Torino, July 8-10 2009. Lee, H. D., Kim, Y., Manual of laboratory mix design procedure for cold in-place recycling using foamed asphalt (CIR-foam), IHRB Report TR 474, June 2007, Public Policy Center, University of Iowa. Little, D. N., Button, J. W., Epps, J. A.. Structural properties of laboratory mixtures containing foamed asphalt and marginal aggregates, Asphalt materials, mixtures, construction, moisture effects, and sulphur, Transportation Research Record 911 Transportation Research Board Washington, DC, 1983, pp. 104-113. Long, F.M., The development of structural design models for foamed bitumen treated pavement layers , Report CR-2001/76, Pretoria, 2001. Losa, M., Bacci, R., Terrosi Axerio, A., Leandri, P., Design of pavements containing foamed bitumen recycled layers, Bearing capacity of roads, railways and airfields (BCRA 09), Taylor & Francis Group, London, 2009. Marradi, A., Verifiche prestazionali su materiali riciclati a freddo, Cold recycling 2007, Roma, 29 novembre 2007. Montepara, A., Valutazione del ruolo del legante sulle caratteristiche meccaniche e prestazionali di conglomerati bituminosi riciclati a freddo con bitumi emulsionati e schiumati, Final report of research committed by Valli-Zabban S.p.A, Sesto Fiorentino (FI), 2008. Muthen, K. M., Foamed Asphalt Mixes Mix Design Procedure, Contract Report CR98/077, Pretoria, 1999. Thgersen, F., Busch, C., Henrichsen, A., Mechanistic Design of Semi-Rigid Pavements An Incremental Approach, Danish Road Institute Report 138, Denmark, 2004. Wirtgen GmbH, Cold recycling manual, Windhagen, 2004.

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iCTi2010, Fortes & Pereira (eds.) 2010, ISBN 978-972-8692-57-5

Performance Study of Different Stabilizers Addition on 50% Dry Sludge from Water Treatment Plant (WTP) of Taiaupeba to Use as Compacted Material in Earthwork DitchesR. Moura Fortes & J. MerighiDepartment of Civil Engineering, Mackenzie Presbyterian University, rmfortes@terra.com.br; jmerighi@terra.com.br

D. Pauli; M. Barros; M. de Carvalho; N. MenettiSABESP - Companhia de Saneamento Bsico do Estado de So Paulo. drpauli@sabesp.com.br; mbarros@sabesp.com.br; mhcarvalho@sabesp.com.br; nmenetti@sabesp.com.br

. Barbosa; B. BentoLENC Laboratrio de Engenharia e Consultoria Ltda alvaro.barbosa@lenc.com.br; benicio@lenc.com.br

ABSTRACT: This present paper is a report from a research that has been carried since 2005 in the Mackenzie Presbyterian University. This research takes part of the CNPq Research Group denominated Sistemas virios (Roads Systems) for use of the sludge from the water disposal treatment in pavement construction as sub-base or roadbed reinforcement. The study presents and discuss the performance of the 50% dry sludge, with 3 to 5% of Portland cement lime or micro granular lime weight addition, looking for an inert material, as defined in the Brazilian Standard (NBR 10004: 2004), attending to the technician-economic-environmental viability with potential to use in workmanships of earthwork ditches. KEY WORDS: Pavement, Laboratory Tests, Dry Sludge, Recycling Materials, Earthwork Ditches, Stabilizer. 1. INTRODUCTION So Paulo is the fourth most populous city in the world, and the largest in the southern hemisphere. Almost 11 million people live within its 1,530 square kilometers, according to the year 2000 Census. The So Paulo Metropolitan Area includes, besides the city itself, 38 other municipalities. As in any great metropolis, the population density is quite high and in many cases, it is difficult to know where the city ends. Having that in mind, the region is home to 20 million people, many from all over Brazil and the world (CIDADE DE SO PAULO, 2009). In many cases, it is found at least six public concessionaires companies associated with municipality activities. In downtown, under a plenty of pavements, there are telephonic cables, gas, energy line, TV cable, petroleum, water and sewage disposal facilities, etc. The local water and sewage disposal facilities concessionaire, named Companhia de Saneamento Bsico do Estado de So Paulo (SABESP), is present in