STEEP SLOPE REINFORCEMENT WITH GEOGRIDS – DEFORMATION BEHAVIOUR UNDER STATIC & CYCLIC LOADING

Jörg KLOMPMAKER, BBG Bauberatung Geokunststoffe GmbH & Co. KG, Espelkamp-Fiestel, Germany Kent VON MAUBEUGE, NAUE GmbH & Co. KG, Espelkamp-Fiestel, Germany Murray BANTING, Applied Geo-Environmental Solutions Inc., Calgary, Canada ABSTRACT The construction of geosynthetic reinforced slopes and retaining walls is continuously increasing and has already developed to a state-of the art technology. Whereas the load-carrying capacity of geosynthetic reinforced soil structures has sufficiently been examined and proven, details for the proof of the deformation behaviour of these structures, especially under cyclic loading rarely exist. This paper will present results from laboratory and large–scale model tests, which have investigated the interaction behaviour between soil and different types of geosynthetic reinforcing elements in combination with the resulting deformation behaviour of the reinforced soil structures under constant and cyclic loading. The paper ends with a case history about the construction of several geogrid reinforced soil structures, which were necessary to establish 10,000 m2 of building land in the mountainous area of Marbella (Andalusia) in Spain. RÉSUMÉ La construction de talus et de murs de soutènement à armature géosynthétique est de plus en plus courante et relève d’ores et déjà d’une technologie de pointe. Les études relatives à la capacité portante des structures de sol à armature géosynthétique et les démonstrations de leur efficacité sont nombreuses. il n’existe, par contre, que peu de résultats sur la déformation de ces structures, et ce, surtout pour les cas de charge cyclique. Cet article présente les résultats d’essais effectués en laboratoire et sur des maquettes à grandeur réelle au cours desquels on a étudié l’interaction entre le sol et différents types d’armature géosynthétique ainsi que la déformation des structures de sols armées sous chargement constant et cyclique. La fin de l’article relate la construction de plusieurs structures de sol à armature de type géogrille qui ont été réalisées sur 10 000 m2 de terrain à bâtir dans la région montagneuse de Marbella (Andalousie) en Espagne. 1. IMPACTS ON GEOSYNTHETIC

REINFORCED SOIL STRUCTURES Vertical static impacts on reinforced soil structures consist of the dead load of the soil and vertical stresses resulting from permanent structures. The static loading on the geosynthetic reinforcement can approximately be determined by the resulting earth pressure on the facing system and its distribution over the connected reinforcing elements. Dynamic impacts can result from:

- Dynamic impacts on the foundation resulting from traffic areas, construction operation as well as due to dynamic stresses of structures - Dynamic impacts on structural parts due to crushes resulting from collision - Earthquakes

2. DEFORMATION BEHAVIOUR OF GEOSYNTHETIC REINFORCED SOIL STRUCTURES

Several investigations concerning the load-carrying capacity of geosynthetic reinforced soil structures have come to the conclusion, that the installation of horizontal reinforcing elements in soil can generate an extremely complex composite material, which offers a behaviour that is different from the summation of the individual material parameters (geosynthetic and soil). From a mechanical point of view, the properties of compound materials are mainly based on the following aspects: Geosynthetic: - Stress-strain behaviour (modulus) - Polymer / manufacturing technique - Aperture size Soil: - shear strength parameters

- Grain size Compound: - Geosynthetic layer spacing - Type and magnitude of impact load - Stiffness of facing system - Allowable deformations The load carrying capacity of geosynthetic soil structures has been proven in large scale model tests (Bathurst et al. 2003), with quasi monolithic sliding wedges (Figure 1).

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Figure 1 Determination of tensile forces in the geosynthetic reinforcing element

The sliding soil wedge is moving against the resisting soil. Due to sufficiently high tensile forces and a sufficiently high embedment length of the reinforcing element into the passive zone, the stability of the sliding wedge is assured. The proof of the serviceability is implied as being evidenced, when the load- carrying capacity can be warranted. Especially for geosynthetic soil structures which are susceptible to settlements (e.g. bridge abutments or retaining walls in railway applications), it is desirable for the warranty of the durability and the serviceability, to be able to forecast the deformations resulting from the effective loads and to compare those with the allowable deformations. Several carried out and monitored projects confirm that the in-situ measured tensile forces of the geosynthetic reinforcing elements partly show lower values as they have been predicted by the design. Due to the rheological properties of the geosynthetics only a small increase of plastic and thus non-reversible deformations develop at low load levels after the construction phase. With the low activated tensile forces under service load, the available tensile force reserves of the reinforcing element are not utilised in comparison to the calculated long-term design strength. High geosynthetic tensile forces can only be activated after the loss of serviceability and lead to a high safety potential of the structure under service loads. The safety potential of geosynthetic reinforced soil structures constitutes the necessity to adjust the load carrying capacity within the scope of the serviceability as well as the bearing capacity to the real conditions. This can only be achieved if the real load distribution inside the compound structure is determined. With the knowledge of the progress of stresses inside the reinforced soil structure, the effective forces can be estimated more precisely and the deformations under service load can be forecasted. For the investigation of the deformations of geosynthetic reinforced soil structures under service load, the mechanical behaviour of the compound material, the influence of the individual material properties (soil and geosynthetic) and the interaction behaviour between both components has to be known.

1.1 Laboratory Model test – Deformation under static loads

The main aim of the model test (Bussert 2006) which is described in the following is the determination of the influencing factors for the interaction between geosynthetic and soil and the determination of the load distribution behaviour under static service loads. For this, a particular section of a geosynthetic retaining wall is examined in laboratory tests. With the variation of possible soil and geosynthetic properties, the influence on the interaction and compound behaviour between soil and geosynthetic and the load carrying capacity of the resulting compound structure is determined. With the distance-dependent registration of the activated stresses and strains inside the geosynthetic reinforced soil structure, the load carrying capacity- reserves can be determined as a function of the deformations in the facing area. For the determination of the boundary conditions of the laboratory test a continuous long geosynthetic reinforced soil structure was assumed. Based on the cinematic degree of freedom, only a horizontal deformation, transverse to the embankment axis can occur. Due to shear deformations inside the compound structure, horizontal deformations lead to vertical deformations at the top surface. The deformation is a two-dimensional state, where deformations only appear transverse but changes in the state of stress also appear parallel to the embankment axis. Deformations in the subgrade or the backfill are neglected. For the investigation, a 9 m high retaining wall is assumed. From deformation measurements it is known that the biggest deformations and horizontal forces appear approx. at 1/3 or ½ of the wall height away from the toe of the structure (Bathurst et al. 2004, Rankilor 2004), which results in a decisive vertical load of 120 kPa on top of a 9m high wall. The test apparatus is shown in Figure 2.

Figure 2 Cross Section of Biaxial test apparatus It consists of a base plate and four rigid side elements. The deformation is forced by a translative movable rigid steel plate, which is hanging in front of six plug gauges at one longitudinal side. There is no

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further contact of the movable steel plate to the four side elements besides at the plug gauges. The stress which is acting on the steel plate during movement can thus be determined without any loss. The horizontal deformation of the movable plate is measured by three spacers that are mounted to the plate. On top of the spacers displacement transducers are attached in the centre of the plate as well as in the area of the bolts. The vertical load on top of the test setup is applied by a hydraulic cylinder and measured by a pressure cell. The settlements of the load plate are monitored by inductive displacement transducers at the edges and in the centre of the plate. The stresses transverse to the direction of movement are measured by strain gauges which are applied to the plug gauges. As fill material 3 different soil types were used:

• silica sand (0-2 mm) • silica gravel (2-12 mm) • gravel sand (0-36 mm)

To achieve constant test conditions, all soils were installed in dry condition. To guarantee a constant density of the installed soil layers, the sand or gravel was rippled through a punched plate. The density was controlled by the drop height and the hole diameter. Several geosynthetics of different manufacturing types (woven, laid, stretched and knitted), different polymers (PET, PP, HDPE) and different stress-strain characteristics (modulus) were used in the tests. The effectiveness of different geosynthetic reinforcing elements can explicitly be derived from the effective horizontal forces at the front face of the biaxial test apparatus. Due to the external loading and the steel plate movement at the front face, grain rearrangement and strains in the geosynthetic reinforcement lead to shear and tensile force activation in the compound material, which change the effective horizontal stresses.

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geogrids (40-55 kN/m) in sand In Figure 3 and 4 the maximum horizontal stresses of the compound material (geogrid & soil) are documented, which can be absorbed at an applied load of 120 kPa and a defined front movement of the steel plate. Using sand as fill material a geogrid layer spacing of 0.4 m and for gravel a vertical layer spacing of 0.75 m has been used. In Figure 1 geogrid products with a tensile strength between 110 kN/m and 120 kN/m have been used whereas in Figure 4 results from geogrids with a tensile strength between 40 kN/m and 55 kN/m are documented. Depending on the manufacturing technique (laid, stretched, woven & knitted) of the used geogrid a different effectiveness in relation to the maximum stress absorption can be determined. In general it can be noticed that the laid geogrid shows the highest effectiveness in gravel as well as in sand. Due to a much higher flexibility of the woven geogrid in comparison to the stretched and laid geogrids, no effective fixed support of the soil is given, which allows a higher deformation capability of the compound material. A higher stiffness of the geogrid also leads to a higher stiffness of the compound material which encourages the stress absorption and low deformations. Further tests within the investigation also document that woven and knitted products need an initial deformation before a reinforcing effect can be measured compared to an un-reinforced system. Due to the production related pre-stressing of laid and stretched geogrids, immediate stress absorption without primary deformations of the compound material takes place. Dimensionally stable and high-modulus geogrids assure an immediate frictional connection with the surrounding fill and increase already the stress absorption capacity of the compound material prior to the movement of the facing. The achievable maximum stress absorption of woven and knitted geogrids is much lower due to a missing stabilising effect in the beginning and the resultant soil movement within the compound material.

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Whereas the overall bearing effect of compound materials reinforced with stretched and laid geogrids consists of a stabilising and reinforcing part, only a reinforcing bearing effect can be achieved with woven or knitted products. The activation of the reinforcing effect is further a result of the stress-strain behaviour of the geosynthetic product. Due to the fact that a higher modulus of the used geogrid normally results in an increase of the dimensional stability, it is incidental that an influence on the bearing strength of the compound material is also given. 1.2 Laboratory Model test – Deformation under

dynamic loads There is still a need for clarification concerning the behaviour of reinforced soil structures under constant dynamic loads, as they are typical e.g. in the safety-relevant field of railway traffic loads. To monitor the behaviour of geosynthetic reinforced soil structures under such dynamic loads, extensive large scale tests have been carried out at the University for Engineering and Economy Dresden (FH) in a 1:1 scale (Göbel, Großmann; 2006). The reinforced soil structure consisted of 4 geogrid layers, which were installed with a vertical spacing of 0.4 m. The embedment length of the installed geogrids was 1.75 m and the width of the reinforced slope was 3m. The slope was built with an inclination of 70° (Figure 5). As fill material sandy gravel (0/32 mm) has been used.

Figure 5: Cross section of test setup As reinforcing element a laid and welded geogrid with a tensile strength of 60 kN/m (md & cmd) was used (Figure 6).

Figure 6: Laid & welded geogrid To be able to monitor the dynamic stability of the reinforced soil structure under realistic railway traffic loads, extensive devices for the measurement of the deformation as well as for the oscillating rates have been installed inside the structure. As dynamic load an alternating load with a lower load level of σu = 14.5 kN/m

2 and an upper load level of σo = 94.5 kN/m

2 at a frequency of 7 Hz was applied to the structure with a hydraulic loading device. These loads typically represent a train with a speed of 200 km/h. In addition to those typical loads, also extreme dynamic loads (frequency of 28 Hz & 40 Hz), which rarely occur in practice, have been applied to the reinforced soil structure. As a result of 12.8 million applied load cycles, maximum vertical deformations of 0.1 mm were measured (Figure 7), whereas the measured horizontal deformations were within the accuracy of measurement. The applied vibration rates are very quickly absorbed over the depth as shown in Figure 8.

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At applied vibration rates of 15mm/s, remaining values of < 5mm/s have been measured already at a depth of 0.50 m underneath the load plate. The magnitude of dynamic impacts on the geogrid directly depends on the depth. It is thus of great importance, at which depth underneath the dynamic load level the first geogrid level is installed.

Figure 9: Top geogrid level in laboratory test

compared to Ril 836

With regard to this respect it is defined in Ril 836 that a minimum vertical distance from the top geogrid layer

• to the foundation level of 0.5 m • to the formation level of 1.0 m & • to the upper level of the rail track of 1.7 m

is required (Figure 9). These regulations have been made on the basis of the present standard of knowledge about the dying out of dynamic loads over depth and can be judged as very conservative. Due to this fact a very small distance between load impact level and top geogrid layer of 0.6 m was chosen in the large-scale test. Even under these extreme test conditions, the reinforced soil structure has proven sufficient load carrying capacity and serviceability. After the test the top geogrid layer has been excavated. The results of the visual inspection can be summarized as follows:

• No damages of the geogrid could be recognized

• Between geogrid and fill soil a good interlocking has been detected

• Abrasion of the geogrid due to high dynamic loads could not be registered

To investigate the mechanical properties of the top geogrid layer after applying 12.8 Mio dynamic load cycles, samples have been tested to measure the remaining tensile strength of the geogrid. Based on the carried out tensile test according to DIN EN ISO 10319 a 3 % lower tensile strength of the installed geogrid was measured, in comparison to a sample from the same production lot that was tested during quality control.

Based on this results, a safety factor for installation damage and dynamic loads of SFInst+Dyn = 1.03 can be derived. According to Hubal (2000), a safety factor SFDyn for the determination of the long-term design strength of the reinforcing element, considering dynamic effects resulting from railway traffic, have to be considered. Recommended values of SFDyn are defined according to the depth of the geogrid layer underneath load level:

• ≤ 1.5 m below load level : SFDyn = 1.5 • ≥ 4.0 m below load level : SFDyn = 1.0

Interim values can be interpolated. Based on the gained test results from the large scale laboratory test it can be concluded that the current standards underestimate the resistance of the tested geogrid against dynamic loads, resp. overestimate the propagation of vibrations over depth and thus have to be reconsidered to allow even more economic geosynthetic alternative solutions in comparison to conventional construction methods. 3. REINFORCED SLOPE IN MARBELLA, SPAIN In the hilly landscape of the Andalusia coastal city Marbella, located about 50 km west of Malaga, land is extremely expensive as well as difficult to develop resulting from the natural topography, which is characterised by a terrain inclination of about 45°. For the establishment of real estate, the Spanish private owner planned to fill up the hilly site to create an area of 10,000 m2 of building land. As an attractive landscaping with natural sea view, the owner separated the total area into 3 main plateaux, which were stabilised by geogrid reinforced retaining walls and steep slopes. To meet an attractive landscaping, different facing systems have been chosen for the different wall and slope sections. The final task was to construct three independently located houses including complexes of recreation facilities, access roads and gardens separated into individual sections with an area of 5,400 m2, 3,000 m2 and 3,000 m2. The original situation of the particular area is shown in Figure 10. The aim was to provide reinforced earth structures to reach the maximum terrain level of 150 m ASL (nominal level above sea level) starting from the lowest level of 130 m ASL by limiting the required maximum height with characteristics of terraces.

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Figure 10 Original site situations in the hills of Marbella / Spain

In total 5 main geogrid reinforced retaining walls and slopes have been constructed to create the above mentioned necessary building land. Single geogrid reinforced earth structures with lengths varying between 60 m and 200 m were required due to the existing topography and design requirements (Figure 11). Two different types of a laid and welded geogrid, manufactured by Naue GmbH & Co. KG, have been installed for these civil works:

• Secugrid 80/20 R6 (primary reinforcement, which is installed with wrap-around-method)

• Secugrid 200/40 R6 (installed at half of normal layer spacing as secondary reinforcement)

Figure 11 Site plan view with 5 wall gradients separating the area

Secugrid is a laid geogrid made of stretched, monolithic polyester (PET) flat bars with welded junctions. The subsoil characteristics are based on in-situ probes. The mountainous region of Marbella is characterised by rocky slopes with bedrock. It is assumed that the subsoil consists of undisturbed rock with sufficient bearing capacity for the planned structures. The subsoil stratification of the mountainous terrain can be characterised as follows:

• In depths of 0.0 m to 2.0 m below terrain level: in-situ filled soil with roots, bushes and turf (removed for construction)

• In depths of 0.6 m to 4.5 m below terrain level: weathered Phyllite has been encountered by probe tests.

• Up to a depth of 7 m: bedrock and outcrop (deepest probe test).

For the reinforced fill the design requirements have specified granular soil with large compaction capability and water permeability coefficients of kf ≥ 1*10-5 m/s to prevent the build up of hydraulic pressures inside the reinforced soil structure. The maximum grain size diameter should not exceed 63 mm (dmax = 63 mm), which has been taken into account for the calculation of the long-term design strength for the geogrid, considering the product specific installation damage reduction factor. Inclinations of 90° (with small intermediate berms) and 70° (continuous slope) have been realised. For all facing systems the wrap-around method has been used. Pre-placed natural blocks as well as sacrificial galvanised steel grid meshes were chosen as facing. The steel grid meshes allow a fast construction rate, because the steel meshes remain in place after the geogrid installation and fill soil compaction. The steel meshes provide a high stiffness supporting a smooth facing. The design has considered a vertical geogrid layer spacing of 60 cm. In the vicinity of the facing elements small manual vibrating compactors have been used. The wrap-around-method includes the placing of vegetation soil (fine-graded top or humus soil) placed directly behind the steel grid elements. To avoid the wash-out of the fine-graded vegetation soil at the wall front a Secutex nonwoven separation and filtration geotextile has been installed. The primary geogrid is used for the wrap-around-method. The higher strength geogrid was installed partly as a secondary reinforcement layer after placing and compacting the first 30 cm of fill soil. The required embedment lengths resulting from the stability analysis were documented in implementation plans and drawings achieving easy installation plans. For each wall individual geogrid layout plans and cross-sections have been prepared to allow an accurate installation. Figure 12 and 13 show the first and largest (10 m high) geogrid reinforced earth structure during construction. Due to the extremely dry summers in the south of Spain and the steep inclination of the bottom wall, an artificial irrigation system, consisting of slotted pipes, has been installed to the facing system.

Figure 12 Construction of the base wall (10 m high)

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Figure 13 Finish of bottom wall

Figure 14 Installation of steel grid facing elements

Figure 15 Installation of natural stone block facing for the semi-circled geogrid reinforced soil structure

(August 2003)

Figure 16 Constructed villa on reinforced soil

structure (May 2006) The geogrid reinforced soil structures as flexible alternative to concrete retaining walls have allowed a cost effective, attractive development of real estate in a difficult topography.

In total 5 different geogrid reinforced soil structures have been realised in Marbella to provide terraced plateaux, filled up with 40,000 m3 of soil. The presented solution provides significant advantages concerning the flexibility in geometry and cost-effectiveness in relation to the regionally expensive land prices and conventional construction methods. 4. CONCLUSION Based on the presented test results from the investigated reinforcing elements in large scale model tests it can be concluded that current design standards for reinforced soil structures clearly underestimate the effectiveness of geosynthetic reinforcing elements with regard to:

• Resistance to dynamic loads • Interaction behaviour between soil &

geosynthetic • Load transfer mechanism inside the

compound material (soil & geogrid) The results of the presented investigations also show that product properties of different reinforcing materials, like e.g. modulus and dimension stability (stiffness) have a decisive influence on the stress absorption of the compound material and its deformation behaviour. Current design standards do not completely allow for the consideration of these influencing factors. Geosynthetic reinforced soil structures often offer ecological and economical advantages compared to conventional construction methods like e.g. gravity or angular retaining walls as shown in the documented case history of geogrid reinforced soil structures in Marbella, Spain. Soong and Koerner (1999) have shown that the costs for geosynthetic reinforced retaining walls are only half, compared to those of gravity walls. The consideration of the new cognitions in combination with further investigations will help to design safe and even more economical steep reinforced soil structures.

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5. REFERENCES Bathurst, R.J., Blatz, J.A., Burger, M.H., 2003.

Performanceof instrumented large-scale unreinforced and reinforced embankments loaded by a strip footing to failure, Canadian Geotechnical Journal

Bathurst, R.J., Allen, T., Walters, D., 2004. Reinforcement loads in geosynthetic walls and the case for new working stress design method, Proc. Of the 3rd European Geosynthetics Conference, Munich, Germany

Bussert, F., 2006. Verformungsverhalten geokunststoffbewehrter Erdstützkörper– Einflussgrößen zur Ermittlung der Gebrauchstauglichkeit, Schriftenreihe Geotechnik und Markscheidewesen, TU Clausthal, Heft 13/2006, Clausthal, Germany

Göbel, C., Großmann, S., 2006. Geokunststoffbewehrte Erde unter dynamischer Belastung- Weiterentwicklung des Systems, 7. Sächsisches Bautextilien-Symposium Bautex 2006, Chemnitz, Germany

Hubal, H., 2000. Geotextilien im Eisenbahnbau-Einsatzbereiche, Erfahrungen und Entwicklungen, Eisenbahningenieur (51) 4/2000

Rankilor, P., 2004. Soil Reinforcement Theory-We may have been wrong for Forty Years, Int. Conference on the Use of Geosynthteics in Soil Reinforcement and Dynamics, 5.-8. September 2004, Schloss Pilnitz, Dresden, Germany

Ril 836, 1999. Erdbauwerke planen, bauen und instand halten, Deutsche Bahn AG, Munich, Germany

Saathoff, F., Werth, K., Klompmaker, J., Wittemöller, J., Vollmert, L., 2004. Stabilisation of new Real Estate in Marbella / Spain with geogrid reinforced soil structures, Proc. Of the 3rd European Geosynthetics Conference, Munich, Germany

Soon, T.-Y, Koerner, R.M., 1999. Geosynthetic reinforced and geocomposite drained retaining walls utilising low permeability backfill soils, GRI Report #24, Geosynthetic Research Institute, Drexel University, USA

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Pages1-108.pdf4-Paper 247.pdf4-Paper 247.pdfINTRODUCTIONSTRATIGRAPHYPILE LOAD TEST PROGRAMPhase 1 – Static Load testsPhase 2 – Osterberg Cell and StatnamicO-Cell SetupStatnamic SetupStatic Creep Test

PILE LOAD TEST RESULTSDISCUSSIONCONCLUSIONACKNOWLEDGEMENTSREFERENCES

6-Paper 270.pdfINTRODUCTIONSCOPE OF WORKTEST SETUPTesting ProcedureResidual StressesResidual Stresses in Model Piles Due to InstallationEstimating the Residual StressesInterpretation of Uplift Test Data

TESTING RESULTSCONCLUSIONSACKNOWLEDGEMENTS

7-Paper 522.pdfINTRODUCTIONIN-SITU TESTING2.1PiezoconeResistivity Piezocone2.3BAT Discrete-Depth Water Sampling System2.5Piezocone Hydraulic Conductivity and Gradient Measuring System

3.RESISTIVITY PIEZOCONE (RCPTU) FOR GEOENVIRONMENTAL SITE CHARACTERIZATION3.1Factors Affecting Bulk Resistivity of Soils

Pore fluid chemistryDegree of fluid saturationPorosity/density of soil matrixTemperatureShape of pore spaceClay contentMineralogyDielectric properties may be important.4.MINE TAILINGS: CASE HISTORY6.CONCLUSIONSReferences

8-Paper 491.pdfINTRODUCTIONBACKGROUNDTESTING PROGRAM AND TEST SITESTesting Equipment and ProceduresTest Sites

TESTING RESULTSEffects of correctionsComparisons of qnet and derivation of N factorsUndrained Shear Strength ProfilesPost Peak and Remoulded Strengths

DISCUSSION AND CONCLUSIONACKNOWLEDGEMENTS

9-Paper 454.pdfINTRODUCTIONSPT ENERGY THEORYROD LENGTH AND SHORT ROD CORRECTIONSTOTAL TRANSFERRED ENERGYFUTURE USE OF SHORT ROD CORRECTIONSSUMMARY AND RECOMMENDATIONSACKNOWLEDGEMENTS

Pages109-218.pdfPaper 370.pdfINTRODUCTIONHistorical SettingGeological SettingHydrogeological Setting

FIELD AND LABORATORY INVESTIGATIONField InvestigationLaboratory InvestigationMoisture ContentHygroscopicyGrainsize Distribution/ Capillary AbilityScanning Electron Microscope

A scanning electron microscopy was used to identify the elemental components of soil, stone and degraded stone samples. This X-Ray DiffractionThin Section

The majority of stone samples were found to be composed of silica sand based sandstone, often with some rock lithic fragments Ion Chromatography

The water sample collected from an open water source near the Habu temple was found to be of fresh water quality. Chloride coThe groundwater sample collected from damp soil in the shallow subsurface near the Karnak temple is the most definitive confirSummary of Findings and Conclusions

FUTURE REASEARCHACKNOWLEDGEMENTS

Paper 120.pdfSITE INVESTIGATION CLAUSESCases where site investigation clauses given full effectCases where site investigation clauses interpreted narrowlyAlternative Claim: Negligent misrepresentationSite Investigation Clauses: SummaryImportance of NoticeMaterial DifferencesSite adjustment clauses typically allow for adjustment to the contract price or the time for completion where the encountered

Paper 96.pdf1. INTRODUCTION2.1.1 Sand

Paper 200.pdfINTRODUCTIONDYNAMIC NUMERICAL MODELLINGModel verificationGrid, Boundary condition and loadingSeismic Soil modelReinforcement modelStructural componentsInterface element model

ANALYSIS RESULTSEffect of reinforcement stiffness (J)Effect of reinforcement length (L0/H)Effect of reinforcement spacing (Sv)

SUMMARY AND CONCLUSIONSREFERENCES

Paper 301.pdfINTRODUCTIONEXPERIMENTAL SHAKING TABLE TESTS AT RMCNUMERICAL SIMULATIONSMaterial PropertiesBackfill soilEPS geofoam

Interface PropertiesNumerical construction and dynamic excitation

NUMERICAL RESULTSCONCLUSIONS

Paper 329.pdfINTRODUCTIONEXPERIMENTAL APPROACHTest FacilityGeneral Arrangement of Wall ModelsMaterialsBackfillReinforcement

Toe ConditionInstrumentationWall Construction

TEST RESULTSCONCLUSIONSACKNOWLEDGEMENTS

Paper 432.pdfBACKGROUNDSITE DESCRIPTIONMONITORING SYSTEM DESIGN AND DESCRIPTION4.1Climate Conditions4.2In Situ Monitoring4.2.1Thermal Conductivity and Automated Soil Moisture/Salinity Sensors4.2.2Portable Soil Moisture Probe4.2.3Field Saturated Hydraulic Conductivity4.3Gas Sampling Ports

4.4Additional Field Monitoring

DISCUSSION5.1In situ Water Content

SUMMARY

Paper 330.pdfABSTRACT

Paper 328.pdfINTRODUCTIONGEOTECHNICAL PROPERTIES OF SILT3.BERM CONSTRUCTION4.SETTLEMENT AND PORE PRESSURES5.STABILITY OF BERM

Paper 341.pdfINTRODUCTIONESSAIS EN LABORATOIREClassification granulométriqueEssais triaxiauxEssais de consolidation et de perméabilité

ESSAIS EN CHANTIEREssais au piézocône (CPT).

DISCUSSION DES RÉSULTATSCONCLUSIONREMERCIEMENT

Paper 348.pdfINTRODUCTIONPROJECT PLANNINGScheduling & Staging of Project

DESIGN OF RAIL STRUCTUREStructural DesignGeotechnical Evaluation & DesignMSE Wall DesignGeneralSpecifics

CONSTRUCTIONMSE Wall ConstructionGeotechnical Monitoring

SUMMATION

Paper 479.pdfINTRODUCTIONDOUBLE-POROSITY MODELOverviewFormulation of the Model

OVERSTRESS VISCOPLASTIC MODELThe Hinchberger and Rowe ModelConceptual Behaviour of the ModelFigure 3 illustrates the conceptual behaviour of the Hinchberger and Rowe (1998) model during a typical oedometer increment wh

COMPARISON OF RESULTSDISCUSSION AND CONCLUSIONS

Paper 158.pdfGEOMECHANICAL BEHAVIOR OF A MCMURRAY SAND FORMATION USING LOCAL STRAIN MEASUREMENTSABSTRACT5. ACKNOWLEDGMENT

Paper 344.pdfINTRODUCTIONK�NEAREST NEIGHBOR METHODDATACompiling Database from the LiteratureChoosing Model Inputs

IMPLEMENTATIONRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTS

Pages219-334.pdfPaper 311.pdfINTRODUCTIONBACKGROUNDEQUIPMENT DETAILS AND METHODOLOGYGeneralDetails of equipment

MATERIAL DESCRIPTION AND PROPERTIESTEST PROCEDUREGeneralTests under fully saturated conditionTests under unsaturated conditions

Bearing capacity tests

DETERMINATION OF THE SOIL WATER RETENT- ION CURVE (SWRC)DISCUSSIONS OF TEST RESULTSSUMMARY AND CONCLUSIONSACKNOWLEDGMENTS

Paper 193.pdfINTRODUCTIONLITERATURE REVIEWBackgroundMajor influencing factorsCorrelation between Mr and CBR or other soil properties

MATERIALS AND TESTING PROGRAMMEMaterials and physical propertiesResilient modulus testing apparatusSample preparation and test procedure

RESILIENT MODULIUS TEST RESULTSSensitivity of resilient modulus to stressSensitivity of resilient modulus to water contentComparison of Mr values from other studies

FINDINGS AND OBSERVATIONSACKNOWLEDGEMENTS

Paper 194.pdfINTRODUCTIONTESTING PROGRAMTEST RESULTS AND DISCUSSIONSStress-strain and volume change responses at different confining pressuresStress-dilatancy plotLimiting envelopes in p’ – q spaceContribution to shear resistance of granular materialsImplementation of the results

CONCLUSIONSACKNOWLEDGEMENTSREFERENCES

Paper 382.pdfINTRODUCTIONLABORATORY TESTING DETAILSTEST RESULTS AND DISCUSSIONConstant-volume Monotonic DSS Loading ResponseConstant-volume Cyclic DSS Loading Response

CONCLUSION

Paper 318.pdfINTRODUCTIONEXPERIMENTAL ASPECTSTEST RESULTS AND DISCUSSIONUndrained monotonic behaviourUndrained cyclic behaviourK Correction Factor

SUMMARY AND CONCLUSIONSACKNOWLEDGEMENTSREFERENCES

Paper 389.pdfINTRODUCTIONDefinition of the Critical StateStress-Dilatancy Definitions

CRITICAL STATE FRICTION RATIO DETERMINATIONEnd of Test (ET) MethodMaximum Contraction (MC) MethodBishop Method (BM)Stress-Dilatancy (SD) Method

OBTAINING THE CRITICAL STATE STRESS RATIO OF TICINO SANDTicino Data ProcessingDiscussion of Results for Ticino SandThe strength from the end of test method, (Mtc)ET =1.445 appears to overestimate Mtc for the dense specimen used here; the sam

OBTAINING THE CRITICAL STATE STRESS RATIO OF ERKSAK SANDErksak Data ProcessingDiscussion of Results for Erksak Sand

CONCLUSIONACKNOWLEDGEMENTS

Paper 324.pdfINTRODUCTIONCOMMENTARY ON JAKY’S ANALYSISTERZAGHI’S VS. JAKY’S RELATIONSHIPSCONCLUSIONSREFERENCES

Paper 455.pdfINTRODUCTION

Paper 461.pdfINTRODUCTIONMETHODOLOGYFluid calibration, unmodified transducerSoil calibrationTransducer modificationModified transducer calibration

RESULTSAir (fluid) calibrationSoil CalibrationDetermination of CAFEstimating soil moduli

Derived parameters

DISCUSSION AND CONCLUSIONSACKNOWLEDGEMENTS

Paper 496.pdfINTRODUCTIONBACKGROUNDEXPERIMENTAL METHODOLOGYTriaxial validation testPhotogrammetric considerationsCalculation of axial, radial, and volumetric strain

RESULTSCONCLUSIONSACKNOWLEDGEMENTS

Paper 190.pdfINTRODUCTIONMATERIALS AND EXPERIMENTAL METHODRheological MeasurementsStandpipe Measurements

RESULTS AND DISCUSSIONRheological dataSedimentation data

BI-VISCOUS MODEL ANALYSISCONCLUSIONACKNOWLEDGEMENTS

Paper 338.pdfINTRODUCTIONROOT DETERIORATION AND ROOT COHESIONSHEAR DISPLACEMENT MODELSROOT ARCHITECTURE AND MORPHOLOGYCOMPUTER MODELING AND ANALYSISROOT-GROUNDWATER-SOIL INTERACTIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES

Pages335-439.pdfPaper 403.pdfINTRODUCTIONNATURE AND ORIGIN OF THE EVENTUBCDFLOW MODEL OF TRAVEL DISTANCESENSITIVITY ANALYSIS OF TRAVEL DISTANCEInitial failure volumeWidth of the event

CONCLUSIONS

Paper 312.pdfINTRODUCTIONFIELD STUDY AREASRESULTSLandslide VolumesRunout DistanceHydrology and HydrogeologySlope LocationHeadscarp StratigraphyContributing Factors

DYNAMIC MODELLINGCONCLUSIONSACKNOWLEDGEMENTSREFERENCES

Paper 300.pdfINTRODUCTIONFIELD INVESTIGATION AND INSTRUMENTATIONINSTRUMENTATION OVERVIEWIntroductionIn-Place InclinometersVibrating Wire PiezometersOther InstrumentationData LoggerARGUS Monitoring Software

INSTRUMENTATION RESULTSDISCUSSIONCONCLUSION

Paper 264.pdfINTRODUCTIONMETHODMETHODA simple ellipsoidal failure surface.A compound slip surface

4. RESULTS AND CONCLUSIONSACKNOWLEDGEMENTS

Paper 195.pdfINTRODUCTIONDIFFERENCES BETWEEN LIMIT EQUILIBRIUM AND FINITE ELEMENT REINFORCEMENT LOADSMETHODOLOGY FOR COMPARING LIMIT EQUILIBRIUM AND SSR RESULTS FOR THE ANALYSIS OF REINFORCED SLOPESRESULTSExample 1Example 2

CONCLUDING REMARKS

Paper 271.pdfINTRODUCTIONCENTRIFUGE MODELLINGModelling of Construction Machinery LoadGround Model PreparationCharacteristics of Ground ModelsTest ConditionsTest Procedures

EXPERIMENTAL RESULTSFailure Mechanism of Sand GroundFailure Mechanism of Kanto Loam Ground

CONCLUSIONS

Paper 464.pdfINTRODUCTION

Paper 216.pdfINTRODUCTIONSITE INVESTIGATIONSubsurface ConditionDetermination of Undrained Shear Strength

SLOPE STABILITY ANALYSISBack Analysis of Slope FailureProbabilistic Slope Stability AnalysisEffect of Excavated Materials

CENTRIFUGE MODELLINGModel PreparationExperimental Results

CONCLUSIONS

Paper 225.pdfSeveral investigations concerning the load-carrying capacity of geosynthetic reinforced soil structures have come to the conclLaboratory Model test – Deformation under static loadsLaboratory Model test – Deformation under dynamic loadsCONCLUSIONREFERENCES

Paper 287.pdfINTRODUCTIONTHE CE (COMMUNAUTE EUROPEENNE)-CONCEPTCONTENT OF THE GUIDELINE (ETAG)Test site geometryTest-setupNet-fence assemblyThe test block

Testing procedureTest parameters and documentationParametersPrecision and tolerances

Classification of net fencesEnergy classesResidual height classification

Allowance of variations between tested and sold productsWorking life of the productQuality management

PRODUCT CERTIFICATION OF ROCK-FALL PROTECTION FENCES IN TIMEFRAME FOR GUIDELINE TO BECOME EFFECTIVERELEVANCE OF THE CE-MARKING FOR THE END-USERTHE AUSTRIAN TESTSITECable carTest platformMonitoring equipment

Paper 358.pdfINTRODUCTIONFIELD INVESTIGATION AND ANALYSISEMERGENCY STABILIZATIONPost Stabilization Analysis

SUMMARYACKNOWLEDGEMENTSREFERENCES

Paper 557.pdfINTRODUCTIONSTATEMENT OF THE PROBLEMLABORATORY RESULTSNUMERICAL ANALYSIS AND DESIGNEVALUATION OF RIVERBANK STABILITYCONCLUSIONSACKNOWLEDGEMENT

Paper 360.pdf1. INTRODUCTION2. PROBLEM3. RESULTS4. SOLUTION6. INSTALLATIONReferences

Paper 481.pdfINTRODUCTIONGENERALIZED INTEGRATED RISK ASSESS�MENT FRAMEWORK (GIRAF)Data CollectionHazard AssessmentHazard Zonation for Regional StudiesHazard Assessment for Specific Slopes

Vulnerability AssessmentElements at riskVulnerability

Risk AssessmentIndividual RiskSocietal Risk

RISK ASSESSMENT IN PRACTICEExampleGIRAFBenefits and limitations

CONCLUSIONSREFERENCES