Road Specifications (1)

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Republic of the PhilippinesDEPARTMENT OF SOCIAL WELFARE AND DEVELOPMENT

KALAHI-CIDSS PROJECT

TECHNICAL STANDARDSPECIFICATION FOR RURAL ROADS

ENGINEERING UNIT

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FOREWORD

The KALAHI-CIDSS-NCDDP Project is a community driven development projectbeing implemented by the Department of Social Welfare and Development with fundingassistance from World Bank and Asean Development Bank. The Project caters the needof the rural and urban communities in terms of social and small infrastructures inaddressing the poverty situation of the locality. Most of the common interventionsidentified by the communities are rural access such as roads and bridges.

Engineering designs plans and specifications are prepared prior to the approval ofthe proposed sub-projects. Considering that the Project requires the proponent to submittechnical specifications for the construction and rehabilitation of road and bridges, TheProject adopted the DPWH Standard Specifications for Roads, Bridges and Ports(Volume II)1 as reference. Modifications on the content were made in order for thetechnical staff to simple understands the specifications and the other aspect of the workitems.

Although there are areas covered by the Project that are isolated such as islandmunicipalities, far flung communities in which available materials may not pass thestandard specification as provided for from the DPWH Blue Book, the Project may adoptthe materials and practices being observed on the particular areas.

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STANDARD SPECIFICATIONS FOR HIGHWAYS, BRIDGES, AND AIRPORTS

PART C – EARTH WORK

ITEM 100 – Clearing and Grubbing102 – Excavation103 – Structure Excavation104 – Embankment105 – Subgrade Preparation

PART D – SUBBASE AND BASE COURSE

ITEM 200 – Aggregate Subbase Course201 – Aggregate Base Course

PART E – SURFACE COURSES

ITEM 311 – Portland Cement Concrete Pavement

PART G – DRAINAGE AND SLOPE PROTECTION STRUCTURES

ITEM 500 – Pipe Culverts and Storm Drains501 – Underdrains505 – Riprap and Grouted Riprap506 – Stone Masonry

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ITEM 100.CLEARING AND GRUBBING

100.1. Description

This item shall consist of the removal and disposal of trees, stumps, brush, roots,vegetation, logs, rubbish and other objectionable matter, as directed by the Engineer.

100.2. Construction Methods

Trees, Vegetation, Rubbish The road width as extended one (1) meter beyond the top ofcut slopes shall be cleared of all objectionable materials.

All roots shall be grubbed to a minimum depth of 0.3 meters and adequate provisions shallmade to ensure that no roots or other objectionable matter is incorporated into the embankment.

Trees mark for preservation purposes shall not be cut. Care shall be taken to protect suchtrees from damage during the clearing and grubbing operations.

Large holes and depressions resulting from grubbing operations shall be backfilled withsuitable material in accordance with, EMBANKMENT construction procedure, with the costincluded under this item.

Demolition Except when so provided for in the Bid Schedule under, REMOVAL OFSTRUCTURES, the cost of demolition and disposal of existing structures, stone, masonry, timber,concrete, pavement, sidewalk, and like materials shall be included in this item.

Holes and depressions resulting from such demolition and removal shall be backfilled withsuitable material in accordance with, EMBANKMENT, work with the cost included under thisitem.

Disposal of Refuse All cleared materials, except those arising from Timber Concessionunder the jurisdiction of the Bureau of Forest Development, shall be burnt or deposited off the sitein areas provided by the Contractor in a manner approved by the KALAHI-CIDSS Engineer.

All suitable lumber found in the project as a result of this work shall be turn over to LGUfor safe keeping.

100.3. Method of Measurement

Clearing and grubbing shall be measured in square meter. Measurement for paymentshall be made for areas specified in this item and for areas of roadway, channel and structuralexcavation as required for the construction or as otherwise directed .

Clearing and grubbing carried out by the Contractor in borrow pits shall not bemeasured for direct payment.

100.4. Basis of Payment

All works performed and measured as provided above, including Demolition in 100-2.2,shall be paid for at the contract unit price for CLEARING AND GRUBBING, which price shall befull compensation for furnishing all labor, equipment, tools, supplies and ioncidentals necessary tocomplete the item.

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ITEM 102. SURPLUS COMMON EXCAVATION

102.1. Description

This item shall consist of excavating and grading the roadway including ditches andapproaches as indicated on the construction drawings and, when directed by the Engineer, shallalso include excavating unsuitable materials below subgrade, removal of slide materials andwidening of roadway cuts and flattening cut slopes to obtain material needed for construction ofembankment.

Excavation for structures shall not be included in this item.

102.2. Construction Method

Utilization or Disposal of Suitable Excavated Materials

Suitable excavated materials shall mean excavated materials deemed by the Engineer to besuitable for use in construction of embankment or other fills.

Unless otherwise specifically indicated on the construction drawings or directed in writingby the Engineer, all suitable materials from excavations shall be utilized in the construction ofembankments or other fills, regardless of the haul distance. NO “OVERHAUL” WILL BE PAID.

When indicated on the drawings or so directed by the Engineer, all suitable materials to bewasted shall be disposed of on sites provided by the Contractor outside the right-of-way, unlesswaste sites inside the right-of-way are designated by the Engineer.

Disposal of Unsuitable Materials. Unsuitable materials shall mean excavated materialsdeemed to be unsuitable for incorporation into embankment or other fills.

Unsuitable materials shall be disposed of on sited provided by the Contractor outside theright-of-way at his own expense.

Rock Excavation. Rock excavation consist of igneous, sedimentary and metamorphic rockwhich cannot be excavated without blasting or the use of rippers, and all boulders or otherdetached stones each having a volume of one cubic meter or more as determined by physicalmeasurements or visually by the Engineer.

Excavation Below Subgrade. Where shown on the drawings or directed by the Engineer,excavation shall be made below the subgrade level in cut areas and/or below the existing groundsurface in fill areas. The materials excavated shall be wasted and disposed in accordance to thisitem.

The areas excavated shall be backfilled with approved materials and compacted inaccordance with, EMBANKMENT construction procedure.

Removal of Slides and Overbreaks. Slide materials and materials from unavoidable overbreakage due to slides shall be removed as directed by the Engineer and utilized or disposed of asprovided by the Project Engineer.

Widening of Cuts. The widening of cuts beyond the limits of the typical section as shownon the drawings is prohibited in all instances except by written order from the Engineer. When sodirected, cuts shall be widened and/or slopes flattened over those shown on the drawings in caseswhere additional materials are required for construction of roadway embankments and other fills.

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Ditches. Ditches shall mean roadway ditches and gutters, changes in channels of streams,inlet and outlet ditches of culverts and other structures and ditches outside the road prism, whetherthe excavation is wet or dry.

All suitable materials excavated from ditches, except materials shown on the drawings tobe placed in dikes, shall be placed in embankments, unless otherwise directed by the engineer.

Selected Materials. The excavation shall be performed in such manner and sequence thatsuitable materials may be selected and removed separately for specific uses in construction ofroadway embankments and other fills.

When practicable, such selected materials shall be hauled directly from excavation to finaluse in construction. If this procedure is impracticable, such selected materials shall be stockpiledfor future use.

No additional or separate compensation will be made for stockpiling and handling ofselected materials, unless specified in the special Provisions and included in the Bid Schedule.

Commencement of Excavation. Hauling of materials from cuts to areas of fill shallproceed only when sufficient compaction equipment is operating at the place of disposition toensure compliance with the requirements of, EMBANKMENT works.

Finishing of Cut Slopes. All earth slopes shall be finished to reasonable smooth surfaces,which will merge, with adjacent terrains without any noticeable break. Rock fragments, whichmove when pried with a crowbar, shall be removed.


Materials Incorporated Into Works. The compensation for excavation of materials used inthe construction of embankments and other fills shall be deemed included in the items relating tothe parts of the works where the material in used.

Roadway Excavation (Solid Rock). When included in the Bid Schedule, the volume of thesolid rock (Vr.) excavation shall be measured in its original position and computed by the averageand area method.

Roadway Excavation (Waste). The volume of waste excavation of both suitable andunsuitable materials to be paid for shall be computed as follows:

a) The total volume of excavation (vt) shall be measured in place and computed bythe average and area method.

b) The volume of unsuitable material (Vv) shall be measured in place and computedby the average end area method.

c) The volume of surplus suitable (Vs) shall be equal to the total volume ofexcavation (Vt), minus the total volume of fill (Vf), minus the volume ofunsuitable excavation (Vv), minus the rock volume (Vr).

Vs = Vt - Vf - Vv - Vr

If the volume of the surplus suitable materials (Vs) thus computed is less than Zero, thenthe value shall be considered as zero.

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d) The volume of waste excavation (Vv) to be paid for shall be the volume of surplussuitable material (Vs), plus the volume of unsuitable material (Vv).

Vv = Vs + Vv (Vs – 0)

No shrinkage factor shall be applied in computing the quantities for payment under thisitem.


The volume, measured as provided above, shall be paid for at the contract unit price percubic meter for ROADWAY AND DRAINAGE EXCAVATION (WASTE) AND ROADWAYAND DRAINAGE EXCAVATION (ROCK), which payment shall constitute full compensationfor all labor, equipment, tools and incidentals necessary to complete the excavation and disposal ofthe materials.

Pay Item No. and Name Unit of Measurement

(1) Roadway and DrainageExcavation (Waste) Cubic Meter

(2) Roadway and DrainageExcavation (Rock) Cubic Meter

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ITEM 104. EMBANKMENT

104.1. Description

This item shall consist of the construction of embankment using acceptable materials fromroadway and drainage excavation, structural excavation and borrow in accordance with thesespecifications and in conformity with the lines, grades and dimensions as shown in the plans or asstated by the Engineer.


Preparation of Embankment foundation. After the embankment foundation has beencleared and grubbed, in accordance with the provisions of, CLEARING AND GRUBBING work,the top 0.20 meter shall be compacted to 95% of maximum density as determined by ASSHTOT180 before starting embankment construction.

When, in the opinion of the Engineer, the foundation material is not satisfactory, theunsuitable material shall be excavated and disposed of and payment for such excavation shall bemade in accordance with, ROADWAY AND DRAINAGE EXCAVATION. The unsuitablematerial shall be excavated to the extent and to the depth specified by the Engineer, and theexcavated area shall be backfilled and compacted as hereinafter specified for placing andcompacting embankments.

When embankment are located on slopes of hillsides, the Contractor shall begin by cuttingbenches into the existing ground not less than 3 meters in width with vertical and horizontal faces.The excavated material, if declared suitable by the Engineer, shall be incorporated into the fill.

Borrow Pits

a) Fill material required in addition to that provided by the excavation in the worksshall be obtained from borrow pits. The contractor shall be responsible for theselection and acquisition of borrow pit areas. All borrow shall be subject to theapproval of the Engineer.

b) The Contractor shall notify the Engineer sufficiently in advance of opening anyborrow area so that the borrow material can be tested before being used.Sufficient time for testing the borrow material shall be allowed.

c) The Contractor shall provide all accesses, clear and remove vegetation, rock,boulders, and unsuitable or oversize materials.

The contractor shall provide adequate supervision in every borrow pit to ensurethat approved borrow in every borrow pit to ensure that approved borrow materialis not contaminated with unsuitable materials. All borrow materials shall besubject to test upon delivery to the job site.

d) Borrow pits shall be excavated to regular widths and shapes and shall be cleanedupon completion so that the sides are neatly trimmed and the bottom graded toallow adequate drainage and away from the works.

e) No separate compensation shall be paid to the Contractor for providing the worksas described above, as these shall be considered incidental to the cost of work item“Embankment Borrow”.

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Compaction Trials. Before commencing the formation of embankment, the contractorshall submit to the Engineer for approval his written proposals for the compaction of each type offill material to be used. The proposals shall include the relationship between the types ofcompaction equipment, and the number of passes required and the methods of adjusting moisturecontent. The contractor shall carry out full scale compaction trials on areas not less than 6 m wideand 50 m long as required by the Engineer and using his proposed procedures or such amendmentsthereto as may be found necessary, shall satisfy the Engineer that all specified achieved.Compaction trials with the various types of fill materials to be used shall be completed beforework with the corresponding materials will be allowed to commence.

Throughout the period when compaction of earthwork is in progress the Contractor shalladhere to the compaction procedures found during compaction trials to be satisfactory for eachtype of material being compacted, each type of compaction equipment employed and each degreeof compaction specified.

At the time of compaction, the moisture content of embankment material shall be such thatthe specified relative compaction will be obtained. Embankment material which containsexcessive moisture shall be dried by aeration as necessary before compacting to obtain requireddensity.

Embankments in swamps or on soft foundation material that will not support constructionequipment shall be constructed as specified in the Special Provisions or as directed by theEngineer. In cases where special instructions are not provided, the lower part of the embankmentmay be constructed by dumping successive loads in a uniformly distributed layer of thickness notgreater than that necessary to support the equipment while placing subsequent layers, after whichthe remainder of the embankment shall be constructed in layers and compacted as specified.

Placing Rock Fill. Rock fill shall be constructed in layers not to exceed 0.75 meter. Largerocks shall be reduced in size until it can be readily incorporated into the 0.75meter layer.Sufficient spalls, fines and/or granular materials shall be incorporated with the coarse rock to fillthe interstices to provide a dense mass. Individual rocks not greater than 1.2 meters in the longestdimension may be placed in the fill if carefully positioned.

The lifts of rock fill shall not be constructed above an elevation 0.75 meter below thefinished subgrade. Only common fill material and selected borrow subgrade when specified shallbe used in the top layers of the embankment.

Compaction of Fills. Roadway embankment of earth material shall be placed in horizontallayers not exceeding 0.20 meter. Each layer of material shall be compacted uniformly by the useof adequate and appropriate compaction equipment and in accordance with the proceduresestablished in Compaction Trials.

Common fill shall be compacted to 90% of maximum density as determined by AASHTODesignation T-180, except that the top 0.15 meter of the embankment shall be prepared asspecified under SUBGRADE contract. In-place density shall be determined in accordance withAASHTO T-191.

Rock fill shall be systematically compacted in a longitudinal direction by approved heavycompaction equipment until there is no visible movement of the fill under the equipment.


The quantity of embankment to be paid for shall be measured in cubic meters compactedin place and accepted, formed of materials arising from any source.

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The accepted quantities measured as provided above shall be paid for at the contract unitprice per cubic meter of EMBANKMENT. Payment shall constitute full compensation forexcavating all materials used to form the embankment, all hauling, placing, watering, rolling, labor,equipment, tools and incidentals necessary to complete the item. NO PAYMENT FOROVERHAUL OF MATERIALS .


(1) Embankment from Roadwayand Drainage Excavation(Common) Cubic Meter

(2) Embankment from Borrow Cubic Meter

(3) Embankment from Roadwayand Drainage Excavation (Rock) Cubic Meter

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ITEM 105. SUBGRADE PREPARATION

105.1. Description

This item shall consist of the preparation of the subgrade for the support of overlyingstructural layers. It shall extend to full width of the roadway. Unless authorized by the Engineer,subgrade preparation shall not be done unless the Contractor is able to start immediately theconstruction of the pavement structure.

105.2. Materials

Unless otherwise stated in the contract and except when the sub-grade is in rock cut, allmaterials below sub-grade level to a depth 150 mm or to such greater depth as may be specifiedshall meet the requirements of Section 107 –2, Selected Borrow Sub-grade.


Prior Works. Prior to commencing preparation of the sub-grade, all culverts, cross drains,ducts and the like (including their fully compacted backfill) ditches, drains and drainage outletsshall be completed. Any work in the preparation of the sub-grade shall not be started unless priorwork herein described shall have been approved by the Engineer.

Subgrade Level Tolerances

The finished compacted surface of the subgrade shall conform to the allowable tolerancesas specified hereunder:

Permitted variation from + 20 mmdesign LEVEL OF SURFACE - 30 mm

Permitted SURFACE IRREGULARITYMeasured by 3-m STRAIGHT EDGE 30 mm

Permitted variation from designCROSSFALL OR CAMBER + 0.5%

Permitted variation from designLONGITUDINAL GRADE over 25 m length + 0.1%

Subgrade in Common Excavation. Unless otherwise specified, all unsuitable materialsbelow subgrade level in earth cuts to a depth 150mm or other depth shown on the plans or asdirected by the Engineer shall be excavated. The materials shall be disposed off in accordance withthe requirements of the works of surplus common excavation.

Where materials has been removed from below subgrade level, the resulting surface shallbe compacted to a depth of 150 mm and in accordance with the other requirements ofEmbankment works.

All materials immediately below sub-grade level in earth cuts to a depth of 150 mm, or tosuch greater depth as may be specified, shall be compacted in accordance with the requirements ofEmbankment works.

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Subgrade in Rock Excavation. Surface irregularities under the subgrade level remainingafter trimming of the rock excavation shall be levelled by placing specified material andcompacted to the requirements of Embankment works.

Subgrade on Embankment. After the embankment has been completed, the full widthshall be conditioned by removing any soft or other unstable material that will not compact properly.The resulting areas and all other low sections, holes, or depressions shall be brought to grade withsuitable material. The entire roadbed shall then be shaped and compacted to the requirements ofEmbankment work Scarifying, blading, dragging, rolling, or other methods of wok shall beperformed or used as necessary to provide a thoroughly compacted roadbed shaped to the cross-section shown on the Plans.

Subgrade on Existing Pavement. Where the new pavement is to be constructedimmediately over an existing Portland Cement concrete pavement and if so specified in theContract the slab shall be broken into pieces with greatest dimension of not more than 500 mm andthe existing pavement material compacted as specified in subsection 109-2.6 as directed by theEngineer. The resulting subgrade level shall, as part of pavement tolerances this work by placingand compacting where necessary a levelling course comprising the material of the pavementcourse to be placed immediately above.

Where the new pavement is to be constructed immediately over an existing asphaltconcrete pavement or gravel surfaced pavement and if so specified in the contract the pavementshall be scarified, thoroughly loosened, reshaped and recompacted in accordance with subsection109-2.6. The resulting subgrade level shall conform to the allowable tolerance of Subsection 112-3.2.

Protection of Completed work. The Contractor shall be required to protect and maintainat his own expense the entire work within the limits of his Contract in good condition satisfactoryto the Engineer from the time he first started work until all work shall have been first started workuntil all work shall have been completed. Maintenance shall include repairing and recompactingruts, ridges, soft sports and deteriorated sections of the sudgrade caused by the traffic of thesections of the subgrade caused by the traffic of the contractor’s vehicle/equipment or that of thepublic.

Templates and Straight-edges. The Contractor shall provide for use of the Engineer,approved templates and straight-edges in sufficient number to check the accuracy of the work, asprovided in this Specification.


Measurement of Items for payment shall be provided only for:

a) The compaction of existing ground below subgrade level in cuts of commonmaterial as specified in this work.

b) The breaking up or scarifying, loosening, reshaping and recompacting of existingpavement as specified in this work. The quantity to be paid for shall be the area ofthe work specified to be carried out and accepted by the Engineer.

Payment for all work for the preparation of the subgrade, including shaping to the requiredlevels and tolerances, other than as specified above shall be deemed to be included in the Pay Itemfor Embankment or Pay Item Selected Borrow Sub-grade whichever is applicable.

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The accepted quantities, measured as prescribed in this work shall be paid for at theappropriate contract unit price for Pay Item listed below that is included in the Bill of quantitieswhich price and payment shall be full compensation for the placing or removal and disposal of allmaterials including all labor, equipment, tools and incidentals necessary to complete the workprescribed in this Item.

Payment will be made under:

Payment Item No. and Name Unit of Measurement

(1) Subgrade Preparation(Common Material) Square Meter

(2) Subgrade Preparation(Existing Pavement) Square Meter

(3) Subgrade Preparation(Unsuitable Material) Square Meter

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ITEM 200. AGGREGATE SUB-BASE COURSE

200.1. Description

This item shall consist of furnishing, placing and compacting an aggregate sub-base courseon a prepared sub--grade in accordance with this Specifications and the lines, grades and crosssections shown on the plans, or as directed by the Engineer.

200.2. Materials

Aggregate for sub-base shall consist of hard, durable particles or fragments of crushedstones, crushed slag, or crushed or natural gravel and filler of natural or crushed sand or otherfinely divided mineral matter. The composite material shall be free from vegetable matter andlumps or balls of clay, and shall be of such nature that it can be compacted readily to form a firmstable sub–base. The sub-base material shall conform the following requirements:

200.2.1. Grading Requirements

Sieve Designation

Standard Alternate Mass Percent PassingMm US Standard

50 2” 10025 1” 55-859.5 3/8” 40-750.075 No. 200 0-12

The fraction passing the 0.075 mm (No. 200) sieve shall not be greater than 0.66 (twothirds) of the fraction passing the 0.425 (No. 40) sieve.

The coarse portion, retained on a 2.00 mm (No. 10) sieve shall have a mass percent ofwear not exceeding 50 by the Los Angeles Abrasion Test as determined by AASTHO T96.

In addition, that portion of the material passing the 0.425 mm sieve shall have a liquidlimit not exceeding 35 and a plasticity index not exceeding 12 as determined by AASGTO T89and T90, respectively. Moreover, the type of grading to be used shall be in accordance with theplans or as directed by the Engineer.

The material shall have soaked CBR value or not less than 25% as determined byAASHTO T-193. The CBR value shall be obtained at the maximum dry density as determined byAASHTO T-180, method D.

200.3. CONSTRUCTION METHOD

Preparation of Existing Surface. Immediately before sub-base material is place, the sub-grade shall be finished or refinished as provided under the construction of Embankment andsubgrade.

Placing. The aggregate sub-base material shall be placed as a uniform mixture on aprepared sub-grade in a quantity which will provide the required compaction thickness. Whenmore than one layer is required, each layer shall be shaped and compacted before the succeedinglayer is placed.

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The placing of materials shall begin at the point designated by the Engineer. Placing shallbe from vehicles especially equipped to distribute the material in a continuous uniform layer orwindrow. The layer or windrow shall be of such size that when spread and compacted the finishedlayer be in reasonably close conformity to the nominal thickness shown on the Plans.

When hauling is done over previously placed material, hauling equipment shall bedispersed uniformly over the entire surface of the previously constructed layer, to minimize ruttingor uneven compaction.

Spreading and Compacting. When uniformly mixed, the mixture shall be spread to theplan thickness, for compaction.

Where the required thickness is 150 mm or less, the material may be spread andcompacted in one layer. When the required thickness is more than 150 mm, the aggregate sub-base shall be spread and compacted in two or more layers of approximately equal thickness, andthe maximum compacted thickness of any one layer shall not exceed 150 mm. All subsequentlayers shall be spread and compacted in a similar manner.

The moisture content of sub-base material shall, if necessary, be adjusted prior tocompaction by watering with approved sprinklers mounted on trucks or by drying out, as requiredin order to obtain the required compaction.

Immediately following final spreading and smoothening, each layer shall be compacted tothe full width by means of approved compaction equipment. Rolling shall progress gradually fromthe sides to the center, parallel to the centerline of the road, and shall continue until the wholesurface –has been rolled. Any irregularities or depressions that develop shall be corrected byloosening the material at these places and adding or removing material until the surface is smoothand uniform. Along curbs, headers, and walls, and at all places not accessible to the roller, thesub-base material shall be compacted thoroughly with approved tampers or compactors.

If the layer of sub-base material, or part thereof, does not conform to the required finish,the contractor shall, at his own expense, make the necessary corrections.

Compaction of each layer shall continue until a field density of at least 100 percent of themaximum dry density determined in accordance with AASHTO T180. Method D has beenachieved. In-place density determination shall be made in accordance with AASHTO T191.

Trial Sections. Before sub-base construction has started, the Contractor shall spread andcompact trial sections as directed by the Engineer. The purpose of the trial sections is to check thesuitability of the materials and the efficiency of the equipment and construction method isproposed to be used by the contractor. Therefore, the contractor must use the same material,equipment and procedures that he proposes to use for the main work. One trial section of about500 square meter shall be made for every type of material and/or constructionequipment/procedure proposed for use.

After final compaction of each trial section, the contractor shall carry out such fielddensity tests and other tests required as directed by the Engineer.

If a trial section shows that the proposed materials, equipment or procedures in theEngineer’s opinion are not suitable for sub-base, the material shall be removed at the contractor’’expense, and a new trial section shall be constructed.

If the basic condition regarding the type of material or procedure change during theexecution of the work, new trail sections shall be constructed.

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Tolerance. Aggregate sub-base shall be spread with equipment that will provide auniform layer which when compacted will conform to the designed level and transverse slopes asshown on the plans. The allowable tolerance shall be as specified hereunder:

Permitted variation from designTHICKNESS OF LAYER 20 mm

Permitted variation from design + 10 mmLEVEL OF SURFACE - 20 mm

Permitted SURFACE IRREGULARITYMEASURED by 3-m straight-edge 20 mm

Permitted variation from designCROSSFALL OR CAMBER + 0.3%

Permitted variation from designLONGITUDINAL GRADE over 25 m length + 0.1%


Aggregate sub-base should be measure in cubic meter. The quantity to be paid for shall bethe design volume compacted in place as shown on the plans and accepted in the completed course.No allowance will be given for materials placed outside the design limits shown on the cross-sections. Trial sections shall not be measured separately but shall be included in the quantity ofsub-base herein measured.


The accepted quantities measured as provided above shall be paid for at the contract unitprice per cubic meter of AGGREGATE SUB BASE including filler material, which price andpayment shall constitute full compensation for furnishing all materials, hauling, placing, watering,rolling, labor, equipment, tools and incidentals necessary to complete the item.


a.) Aggregate Sub-Base Course Cubic Meter

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ITEM 201. AGGREGATE BASE COURSE

201.1. Description

This item shall consist of furnishing, placing and compacting a base course composed ofnatural gravel/crushed stone and filler materials, constructed on a prepared roadbed in one or morelayers, in accordance with these specifications and in conformity with the lines, grades and typicalcross-sections shown on the drawings.

201.2. Materials

Materials for aggregate base course shall consist of hard, durable fragments of stone orgravel and filler of sand or binder which meets the quality requirements. The composite materialshall be free from vegetable matter and lumps of clay and be uniformly graded to conform with therequirements given in Table 201-1 and 201-2 for the grading specified in the Bid Schedule.

That portion of the material retained on a 4.75 mm sieve shall be known as coarseaggregate, and that portion passing a 4.75 mm sieve shall be known as filler.

TABLE 201-2 Requirements for Grading (Natural Gravel)

Sieve Designation Mass Percent PassingStandard Alternate Grading A Grading Bmm US Standard

50 2” 100 -37.5 1 ½” - 10025.0 1” 60-85 -19.0 ¾” - 60-8512.5 ½” 35-65 -4.75 No. 4 20-50 30-550.425 No. 40 5-20 8-250.075 No. 200 0.12 2-14

TABLE 201-2 Grading Requirements (Crushed Aggregates)

Sieve Designation Mass Percent PassingStandard Alternate Grading A Grading B

mm US Standard

37.5 1 ½” 100 -25 1” - 10019 ¾” 60-85 -12.5 ½” - 60-904.75 No. 4 30-55 35-650.425 No. 40 8-25 10-300.075 No. 200 2-14 5-15

For all grading, the percentage passing the 0.075mm sieve shall not be greater than 2/3 thepercentage passing the 0.425mm sieve.

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The coarse aggregate shall have a percentage of wear not exceeding 50 at 500 revolutionsas determined by AASHTO Method T-96.The portion of the filler passing the 0.425mm sieve, including any blended filler, shall have liquidlimit of not more than 25 and a plasticity index of not more than 6 as determined by AASHTOMethod T-89 and T-90, respectively.

The material passing the 19mm (3/4 inch) sieve shall have a soaked CBR value of not lessthan 80% as determined by AASHTO T-193. The CBR value shall be obtained at the maximumdry density (MDD) as determined by AASHTO T180 Method D.

If crushed gravel or crushed stone aggregate base is specified in the Bid Schedule, not lessthan sixty percent (60%) by weight of the coarse aggregate particles shall have at least one (1)fractured face.

201.3 Construction Methods

Preparation of Roadbed - Before any base course material is being placed, the roadbedshall be prepared and finished as provided for under Item 112 Sub-grade and other applicableitems of these Specifications.

Placing and Spreading - The base course shall be spread on the prepared surface in layersof uniform thickness, mixed and compacted as herein specified. The compacted thickness, of anyindividual layer shall not be greater than 0.15 meter. Spreading shall be by approved equipmentcapable of distributing the material without segregation.

Mixing - After the base material has been deposit as described above, water should beadded. If required using approved watering equipment. The base material shall be thoroughlymixed to the full depth of the layer by means of a self-propelled blade grader, pulvi-mixer or otherequipment approved by the Engineer. When uniformly mixed, the material shall be spread andfine graded and compacted to the cross-section shown on the drawings.

Additional Filler - Additional filler, when required and when not added at the screeningplant, shall be spread in a uniform layer over the loosely spread base material as specified by theEngineer, and then watered and mixed as described above.

Trial Sections - At least ten (10) days before the construction has started the Contractorshall spread and compact trail sections as directed by the Engineer. The object of the trial sectionsis to check the suitability of the materials and the efficiency of the equipment and constructionmethods proposed by the Contractor. Therefore, the contractor shall use only the materials,equipment and procedures which he has proposed for the work. One trial section of approximately500 square meters shall be made for every type of material and/or construction equipment andprocedure proposed for use.

If a trial section shows that the proposed material, equipment or procedures in theEngineer’s opinion are not suitable, the material shall be removed at the contractor’s expense, anda new trial section shall be constructed.

If the basic conditions regarding type of materials, equipment or procedures change duringthe executive of the work, new trial sections should be constructed when directed by the Engineer.

Tolerances - The aggregate base course shall be lain to the designed level and transverseslopes shown on the Plans. The allowable tolerances shall be in accordance with the following:

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Permitted variation from designTHICKNESS OF LAYER + 10 mmPermitted variation from design + 5 mmLEVEL OF SURFACE - 10 mm

Permitted SURFACEIRREGULARITYMeasured by 3-m straight-edge 5 mm

Permitted variation from designCROSSFALL or CAMBER + 0.2%

Permitted variation from designLONGITUDINAL GRADEOver 25 m length + 0.1%

Compacting - Immediately after fine grading, the base material shall be compacted to thefull width, using adequate and appropriate compaction equipment and in accordance with theprocedures established under 200-3.5, Trial Sections.

Rolling shall continue until the actual density of the layer being compacted reaches 100%of the maximum dry density as determined by AASHTO T180, Method D. In-place density shallbe determined in accordance with AASHTO T191.

Surface Finishing - If irregularities in the surface, or parts thereof, exceed 5 mm in depthwhen measured with a 3 meter long straightedge; required grade and cross-section, water andrecompact to produce a smooth surface free of cracks or loose materials.


Aggregate base course would be measure by the cubic meter (m 3). The quantity to bepaid for shall be the design volume compacted in place as shown in the plans, and accepted in thecompleted base course. No allowance shall be given for materials placed outside of the designlimits shown on the cross-sections. Trial sections shall not be measured separately but shall beincluded in the quantity of aggregate base course.


The volume of AGGREGATE BASE COURSE material determined as provided aboveshall be paid for at the contract unit price per cubic meter which price and payment shall constitutefull compensation for furnishing, transporting and placing the material; for mixing and blading, forall rolling and watering; and for reconditioning of subgrade, shoulders and gutters.


(1) Aggregate Base Course Cubic Meter (cu.m.)(Crushed)

(2) Aggregate Base Course(Uncrushed) Cubic Meter (cu.m.)

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ITEM 311. PORTLAND CEMENT CONCRETE PAVEMENT

311.1. Description

This item shall consist of a pavement of portland cement concrete, with or withoutreinforcements, constructed or a prepared base in accordance with the specifications and inconformity with the lines, grades, thickness and typical cross section shown in the plan.

311.2. Materials

Portland Cement – The type of cement to be use shall be Portland Cement Type 1( ASTM C150 ). Different brand of cement shall not be use nor other types of cement unless thedesign mix is approved. Partially set cement or which contains lump of cement cake shall berejected. Cement salvaged from discarded or used bags shall not be used. Sample testing shall bein accordance with ASSTHO T 1217.

Fine Aggregates – It shall consist of natural sand, stone screening, having hard, strong anddurable particles, and must be taken from approved source by DPWH. Fine aggregates fromdifferent sources shall not be mixed at storage or stockpile area. Beach sand shall not be allowed.This shall be free from injurious effect of organic impurities. It shall be well graded from courseto fine and shall conform to the following table:

311.2.1. Grading Requirements for Fine Aggregates

Sieve Designation Mass Percent Passing

9.5 mm (3/8 in) 1004.75 mm ( No.4) 95 - 1001.18 mm (No.16 45 – 800.300 mm (No.5) 5 – 300.150 mm (No.100) 0 – 10

Course Aggregate – It shall consist of crushed stone, gravel, blast furnace slag or otherapproved materials of similar characteristics; having hard, strong, durable pieces and free from anyadjacent coatings, and must be taken from approved source by DPWH. It shall have a masspercent of wear not exceeding forty (40) percent when tested by ASSHTO T96. When subjected tofive (5) cycles of the sodium sulfate soundness test, the weighted loss shall not exceed twelve (12)mass percent.

311.2. 2 Grading Requirement for Course Aggregates

Sieve Designation Mass Percent Passing

Standard Alternate Grading Grading Gradingmm U.S. Standard A B C75 3 in. 10063 2 ½ in. 90 – 100 100 10050 2 in. 90 – 100 95 - 10037.5 1 ½ in. 25 – 60 35 – 7025 1 in. 0 – 15 35 – 7019 ¾ in. 0 – 1012.5 ½ in. 0 - 5 0 - 5 10 - 304.75 No. 4

Water – Water to be used shall be clean and free from oil, acid alkali, grass or othersubstances impervious to the finish product. Potable water maybe used without tests.

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Reinforcing Steels – Reinforcing steel dowel to be used shall conform to the requirementsof ASSHTO M 31 or M 42. During its use, dowels shall be free from rust, oil, or grease coatings.

Joint Fillers – Poured joint fillers shall be mixed asphalt and mineral or filler conformingto the applicable requirement of joint filler materials.

All materials shall be stored in proper places. Cement shall be stored on a weather proofbuilding which will protect the cement from dampness. Floor shall be raised to the ground. Fineaggregates and course aggregates shall be stored and or stockpiled separately to avoidcontamination from injurious substances. Steel bars shall be stored properly to keep them awayfrom rust.

311.2.3. Proportioning of Concrete

Prior to any concrete works, the contractor shall prepare in the presence of PRIE the trialmix for type of concrete mix needed in the sub-project. This trial mix shall be in accordance to theproposed concrete design mix submitted by the contractor. In order not to delay further the work,the contractor at the presence of PRIE will allowed to crushed one concrete cylinder sample at the7th day from the time it was casted for the said concrete the trial mix. The requirement shall bethat the test at the 7th day crushing must not fall below 75% of the required compressive stress. Ifthe test samples fails to meet the required compressive stress for the 7th day, then the two samplesshall be tested at the required period of 28 days. If it fails again, then the contractor mustundertake another set of trial mix until the results of test samples will be satisfactory. During thisstage, determination of quantity of water to have a good consistency of concrete shall be made inorder to get a slump from 75mm to 100mm. The desired strength of concrete at 28th day,compressive strength test shall be 3,500 psi.

311.3. Construction Requirements

Prior to any concrete paving activities, the Provincial Rural Infra Engineer (PRIE) or theProject Site Inspectors shall undertake the following:

1.) Check whether the sub-base or base have been tested have pass the required FieldDensity Test (FDT);

2.) Availability of Water Supply;

3.) Working condition of working equipment such as: portable concrete mixer, transitmixer including its accessories;

4.) Number and types of hand tools and finishing tools;

5.) Provision of curing;

6.) Size and organization of crew to place, finish and cure concrete;

7.) Check if the forms are air tight before the pouring;

8.) Levels, alignment and elevation;

9.) Result of the trial mix.

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311.3.1. Mixing Concrete

The concrete maybe mixed at the site in a central mix plant or in truck mixers. The mixershall be of an approved type and capacity. Mixing time will be measured from the time allmaterials, except water are in drum.

When mixed at the site or in a central mixing plant, the mixing time shall not be less thanfifty (50) seconds or more than ninety (90) seconds.

Four seconds shall be added to the specified mixing time if timing starts the instant theskip reaches its maximum raised position. Mixing time ends when the discharge chute opens.Transfer time in multiple drum mixers is included in mixing time. The contents of an individualmixer drum shall be removed before a succeeding batch is emptied therein.

The mixer shall be operated at the drum speed as shown on the manufacturer’s nameplateattached on the mixer. Any concrete mixed less than the specified time shall be discarded anddisposed off by the contractor at his expense. The volume of concrete mix per batch shall notexceed the mixer’s nominal capacity in cubic meter, as shown on the manufacturer’s standardrating plate on the mixer, except that an overload up to ten (10) percent above the mixer’s nominalcapacity permitted provided concrete test data strength, segregation, and uniform consistency aresatisfactory, and provide no spillage of concrete take place.

Mixed concrete from the central mixing plant shall be transported in truck mixers, truckagitators, or non-agitating trucks. The time elapsed from the time water is added to the mix untilthe concrete is deposited in place at the site of the work shall not exceed forty five (45) minuteswhen the concrete is hauled in non-agitating trucks, nor ninety (90) minutes when hauled in truckmixers or truck agitators.

Retampering concrete by adding water or by other means shall not be permitted, exceptthat when concrete is delivered in truck mixers, additional water may be added to the batchmaterial and additional mixing be performed to increase the slump test to meet the specifiedrequirements, if permitted by the Engineer, provided all these operations are performed withinforty five (45) minutes after the initial operation and water-cement ratio is not exceeded.

311.3.2. Limitation of Mixing

No concrete shall be mixed, placed or finished when natural light is insufficient.

No manual mixing will be allowed. One-bagger mixer is the minimum requirements.

Water-cement ratio must be properly observed. Approximately 16 ot 20 liters per bag ofcement mixture.

Concrete not in place within ninety (90) minutes from the time the ingredients werecharged into the mixing drum or that has develop initial set shall not be used. Retampering ofconcrete or mortar, which has partially hardened, that is remixing with or without cement,aggregate and water shall not be permitted.

311.3.3. Placing Concrete

Concrete shall be deposited upon the subgrade evenly and in a manner that requires aminimum of rehandling and redistribution. Unless truck mixers or non-agitating haulingequipment are equipped with means to discharged concrete without segregation of the materials,the concrete shall be unloaded into an approved spreading device and mechanically spread on the

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grade in such a manner as to prevent segregation. Placing shall be continuous between transversejoints without the use of intermediate bulkheads. Necessary hand spreading shall be done withshovels.

311.3.4. Finishing

The finishing of the surface is perhaps the most important step in pavement construction.The riding public is entitled to expect a smooth-riding, skid resistant surface. Properly constructedjoints, uniform texture of final finish and freedom from irregularities are all important in obtaininggood riding qualities.

Finishing at Joints – The concrete adjacent to joints shall be compacted or firmly placedwithout voids or segregation against the joint material, also under and around all load-transfertransfer devices, joint assembly units, and other features designed to extend into the pavement.

311.3.5. Machine Finishing

a.) Non-Vibratory Method – The concrete shall be distributed or spread as soon as placed,then it shall be struck off and screeded by an approved finishing machine. The machine shall goover each area of pavement as many times and at such intervals as necessary to give propercompaction and leave surface of uniform texture. Excessive operation over a given area shall beprovided. The tops of the forms shall be kept clean so that the machine may ride directly on themwithout wobbling or other variation tending to affect the precision finish.

During the first pass of the finishing machine, a uniform ridge of concrete shall bemaintained ahead of the front screed in its entire length. Workmen should not track dust or mudinto it, nor should the sub-grade or base materials be sprinkled in such a way that dust is thrown onthe exposed edge of the slab. Footprints made in the concrete after it has been struck off are dugout with a shovel and the depression thus formed is filled with concrete.

Whenever the mixer is shut down for more than thirty (30) minutes a construction jointshould be installed. If this is not done, a sloping plane of weakness will be left which may push upwhen the concrete expands or cause a crack as the slab contracts. When the mixer is stopped for ashorter period the new and old concrete should be thoroughly mixed with the spreader or slicedtogether with shovels to make sure that no cleavage plane is left.

Concrete shall be deposited as near as possible to the expansion and construction jointswithout disturbing them, but shall not be dumped from the discharged bucket or hopper into a jointassembly unless the hopper is well centered on the joint assembly.

b.) Vibratory Method – Concrete should be vibrated since such method permits thesatisfactory placing of denser and stronger mixes than possible by hand tamping. Vibrators shouldnot be used to move concrete laterally and should not be inserted and withdrawn vertically at closeintervals. A systematic pattern of vibration should be used to insure that all concrete have beenadequately consolidated.

Vibration shall be of sufficient duration to provide through compaction, but not prolongedso as to cause segregation.

Vibrators shall operate at a frequency of 8,300 to 9,600 impulses per minute under load ata maximum spacing of 60 cm.

Floating – After the concrete has been struck off and consolidated, it shall be furthersmoothed by means of a longitudinal float, either by hand or mechanical method.

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a.) Hand Method – A manually operated longitudinal float should be used. It may bemade of a plank not less than 265 cm in length and 15 cm in width, properly stiffened to preventflexibility and warping. Two men who stand on bridges spanning the pavement handle thislongitudinal float. It is laid on the pavement at one edge and pulled toward the other edge with awiping motion, leveling transverse ridges and other high spots and filling depressions. Thelongitudinal float is an efficient tool for getting a smooth-riding surface because it eliminates thetransverse ridges sometimes left by screeds.

b.) Mechanical Method – The mechanical longitudinal float shall be of a design approvedby the Engineer, and shall be in good working condition. The float is operated transversely acrossthe pavement with its longitudinal axis approximately parallel to the centerline and it shall pass atleast two times over each area of the pavement, but excessive operation over a given area will notbe permitted. Any excess water or soupy materials shall be waste over the side forms on each pass.

Straight-Edge Testing and Surface Correction – Following longitudinal floating, thesurface is scrapped to remove small ridges left by the transverse finisher or longitudinal float, butwhile the concrete is still plastic, the surface of the concrete shall be tested for real with 300 cmlong straight-edge. The straightedge shall be held in contact with the surface in successivepositions parallel to the road centerline and the whole area gone over from one side of the slab tothe other as necessary. Straightedge testing and surface corrections shall be continued until theentire surface is found to be free from observable departures from the straightedge and the slabconforms to the required grade and cross-section.

Final Finish – If the surface texture is broom finish, it shall be applied when the watersheen has practically disappeared. The broom shall be drawn from the center to the edge of thepavement with adjacent strokes slightly overlapping. The brooming operation should be soexecuted that the corrugation produced in the surface shall be uniform in appearance and shall notbe more than 1.5 mm in depth. Brooms shall be of the quality, size and construction and beoperated so as to produce a surface finish meeting the approval of the Engineer.

If the surface texture is belt finish, when straight-edge is complete and water sheen haspractically disappeared and just before the concrete becomes non-plastic, the surface shall bebetted with a 2-ply canvass belt not less than 20 cm wide and at least 100 cm longer than thepavement width. The object of belting is the even distribution of the surface mortar and theproduction of a granular, gritty surface that provides uniform fraction.

a.) Edging - After the final finish, but before the concrete has taken its initial set, theedges of the pavement along each side of each slab, transverse expansion joints, formed joints,transverse construction joints, shall be worked with an approved tool and rounded to the radiusrequired in the plan.

At all joint, any tool marks appearing on the slab adjacent to the joints shall be eliminateby brooming the surface. In doing this, the rounding of the corner of the slab shall not bedisturbed.

At all joints, care must be taken to prevent the newly finished surface overhanging thebody of the adjacent slab.

Surface Test – As soon as the concrete pavement has hardened sufficiently, the surfaceshall be test with a 3-m straight edge or any specified device. Any area showing high spot greaterthan 3 mm but not exceeding 12 mm in 3-m shall be marked and immediately ground down withan approved grinding tool to an elevation where the area will not surface deviation in excess of 3mm. Where the departure from correct cross-section exceeds 12 mm, the pavement shall beremoved and replaced by and at the expense of the Contractor.

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Any area or sections on the pavement so removed shall not less than 1.5 m in length andnot less than the full width of the lane involved.

Curing - Curing is the treatment or protection given concrete during the hardening period.Proper curing consists of keeping the concrete moist and warm to insure adequate hydration of thecement and to protect the concrete against early shrinkage due to the loss of moisture or abruptchanges in temperature. Strength lost due to lack of warmth or moisture during the first few dayscannot be regained by subsequent curing. Pavement, which has been properly cured, has higherstrength and better durability than the poorly cured pavement.

Removal of Forms – Forms for concrete shall remain in place undisturbed for not less thantwenty-four (24) hours after concrete pouring. Crowbars should be used in the removal of formsby pulling out nails and pins. Care should be taken so as not to break edges nor disturb thepavement. Major honeycombed area will be considered as defective work and shall be removedand replaced at the expense of the Contractor. Any area or section so removed shall not be lessthan the distance between weakened plane joint nor less than the full width of the lane involved.

Sealing Joints – After the concrete has hardened and sufficiently and before the pavementis opened to traffic, all joints must be filled with sealing materials. Immediately before sealing thejoints, they should be cleaned in such a manner those all-loose and foreign materials, includingmembrane curing compound is removed.

The pouring should be done in such a manner that the materials would not be spilled onthe exposed surfaces of the concrete. The sealing materials shall be applied to each joint openingto conform to the details shown on the plans or as directed by the Engineer.

Seals should be install by suitable tools, without elongation and secured in place with anapproved lubricant adhesive that shall cover both sides of the concrete joints.

Protection of Pavement – The Contractor should protect the pavement and itsappurtenances against both public traffic and traffic caused by its own employees and agent bydesignating watchmen to direct traffic and the erection of warning signs, lights, pavement bridgesor cross-over.

Any damage to the pavement occurring prior to final acceptance shall be replaced or thepavement is replaced.

311.3.6. Acceptance of Concrete

The strength of concrete shall be considered satisfactory if the average of all sets of allthree (3) consecutive strength results equal or exceeds to the specified strength fc’ and noindividual strength test results shall be deficient by more than 15% of the specified fc’.

The concrete core taken, it will be considered adequate if the average strength of the coresis equal to at least 85% of and if no single core is less than 75% of the specified strength fc’.

311.3.7. Adjusted Price due Strength Deficiencies

Percent less Percent (%) of Contract

5 to less than 10 95%10 to less than 15 70%Beyond 15 % Replacement

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311.3.8. Thickness Tolerances

The allowable thickness tolerance for concrete pavement shall be +5mm on cases whenthickness deficiencies will be beyond + 10mm, the pavement which have this type of thickness beremove and replace by the contractor at his own expenses.


Under this work item, the contractor shall be paid in square meter of payment placed andaccepted in the completed pavement. Length measurement shall be done longitudinally andhorizontally.

Payment Item No. And Name Unit of Measurement

Portland Cement Concrete Pavement Square Meter (sq.m.)

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ITEM 500. PIPE CULVERTS AND STORM DRAINS

500.1. Description

This item shall consist of the construction or reconstruction of pipe culverts and stormdrains in accordance to the plan and in conformity with lines and grades.

500.2. Materials

Under this project; the materials that is required for the work shall be reinforced concreteculvert storm drain and sewer pipe AASHTO T 170. Mortar to be use in this work shall consist ofone (1) part by volume of Portland cement and two parts of approved sand with water necessary toobtain the required consistency. Mortar shall be used within 30 minutes after its preparation.Backfilling materials to be use shall be in conformity with materials used in the roadway.


Trenches for pipe culverts shall be excavated the depth and width as specified in the plan.Once the desired dimension of trench has been attained; the base shall be compacted by the use ofplate compactor until it has attained a compaction density of 95.00%. Once prepared the beddingmaterials as approved shall be spread and compacted to a compaction density of 95.00%.

If the plan calls for concrete bedding materials, then the concrete mix to be used shall bethose that will attain 2,500 psi when tested at 28 days compressive test. Laying of RC pipes shallstart the downstream section of the stream or conduit progressing upstream. Outsides joints shallbe covered with mortar grout at least 75 mm thick and 120 m wide. Inside joints of the conduitsshall likewise be provided with mortar grout all around. Continuation of backfilling at the sides ofthe pipes shall commence when the mortar has attained the strength sufficient enough not to crack.Materials to be used in backfilling shall be the same as that of the adjacent. Backfilling proceduresat the top section of the conduit/RC pipes shall conform to the corresponding type of work for theroadway.


Under the item the work completed shall be paid per Line Meter including excavation,bedding construction backfilling and other incidental works needed to complete the project.

Payment Item No. and Name Unit of Measurement

(1) Pipe Culverts, _____mm. Linear Meter (ln.m.)(2) Storm Drain, ______mm. Linear Meter (ln.m.)

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ITEM 505. RIPRAP AND GROUTED RIPRAP

505.1. Description

This item shall consist of the furnishing and placing of riprap with or without grout as thecase maybe, furnished and constructed in accordance to lines, grades and dimensions shown on theplans.

505.2. Materials

Stones for riprap shall consist of rock as nearly rectangular in section as is practical. Thestones shall be sound, tough, durable, dense, resistant to the action of air and water and suitable inall respects for the purpose intended.

Stones to be used in the project shall be Class “A” and Class “B” stone shall be used asfoundation, while class “A” stone shall be used on work above foundation.

When filler materials are required and are shown on the plane: riprap shall be placed toprevent fine embankment materials to be washout.

Mortar for grouting riprap shall consist of sand, cement and water conforming to structuralconcrete requirements. This shall be mixed in a proportion one part of cement to three (3) parts ofsand by volume and water sufficient to produce a thick but fluid mortar.


Excavation: Bed of riprap shall be excavated to the required depths and properlycompacted trimmed and shaped. The bed shall be below the scoured depth or as shown on the plan.

Placing: Placing of stones shall be done manually. Stone place underwater shall bedistributed early. Laying and placing of stones shall be closed and shall be finally bedded into theslope and against the stones. Spaces between the stones shall then be filled with cement, mortar.Sufficient mortar shall be used to completely fill the voids except that the faces of the stones shallbe left exposed. Grout shall be placed from the bottom to top of the surface swift with stiff broom.Curving of grouted riprap shall for a period of three (3) days.


Basis of payment under this item shall be in cubic meter including form works temporarybracing and other incidental items relative to the work.


(1) Riprap, Class A Cubic Meter (cu.m.)(2) Riprap, Class B Cubic Meter (cu.m.)(3) Riprap, Class C Cubic Meter (cu.m.)(4) Riprap, Class D Cubic Meter (cu.m.)(5) Grouted Riprap, Class A Cubic Meter (cu.m)

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ITEM 506. STONE MASONRY

506.1. Description

This item shall consist of stone masonry in minor structures in headwalls for culverts andretaining walls as the case maybe.

506.2. Materials

Stone: Stones to be used under this work shall be clean, hard and durable. Adobe stones,limestone and other similar stones shall be used. All stones to be used shall not be less than 150mm in diameter. This shall be dressed to removed any of this or weak portions and provide bedand joint lines to ensure a form bedding.

Mortar: Cement fine aggregates and water shall conform to the requirements of materialsfor structural concrete. Mortar for masonry shall composed of one (1) part of portland cement andtwo (2) parts of fine aggregates by volume and sufficient water to make the mortar of suchconsistency that it can handle easily and spread with towel. Mortar that is not used within 90minutes after water has been added shall be discarded. Retempering of mortar shall not bepermitted.


Foundation are which the stone will be placed shall be excavated and trimmed inaccordance to the plan. Before placing of the stones; this shall cleared thoroughly and wettedimmediately. All stones shall be place in one (1) row at the same elevation. Once in place, thestones shall be moisture prior to spreading of mortar. All joints shall be placed with mortar. Insucceeding layers, all stone shall be place and handle so as not to jar or displaced all stones alreadyset. Joints in stones may vary from 20 mm to 50 mm in thickness. Face stones shall be at least 150mm. longitudinally and 50 mm vertically. At no place shall corners of four (4) stones be adjacentto each other. Backing shall be built chiefly of large stones and shall be constructed in workmanlike manner. All openings shall be filled completely with mortar or with spalls surroundedcompletely by mortar. Constructive at the top sections of structure shall be made of stones that willcover the entire width of the wall. It shall have a minimum concrete coping of 150 mm. Weepholes as called for in the plans shall be provided with a 2” diameter PVC pipe.


Payment for this item shall be in cubic meter constructed/built. This includes all incidentalworks and materials needed in the work.


Stone Masonry Cubic Meter (cu.m.)

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UNDERDRAIN (RCPCWITH __________)

Description

General. The work shall consist of the construction of culverts and drainage pipesaccordance with the lines, grades and dimensions on the drawings or as ordered by the Engineer.

The work shall includes excavation and backfill for the pipe, the bedding, the furnishingand laying of the pipe, the construction of such joints and connection to other pipes, or otherstructures as may be required to complete the work as shown on the drawings or as required by theEngineer.

The work shall also include the removal and disposal of unsuitable material below grade inthe excavation and the refilling of the excavation to grade with selected materials.

The work shall also include the removal and disposal of existing culverts, pipes andheadwalls as shown on the drawings or as directed by the Engineer.

Unless otherwise permitted by the Engineer, the Contractor shall not order and deliver thepipes for any work until the Engineer has approved correct list of sizes and lengths.

Materials

Materials and Manufacture. The pipe shall meet the requirements of Reinforced ConcreteCulvert Pipe, AASHTO Designation M.-170.

Construction Methods

Excavation. A trench shall be excavated to the depth and grade required with dueallowance for chamfer. The bottom of the trench shall be shaped to fit the pipe for at least 10percent of the depth of the pipe. The width of the trench shall not be greater than necessary topermit adequate compaction of the backfill materials under and around the pipe. The bedding shallprovide a firm foundation of uniform density for the entire length of the culvert.

Where rock or soft materials is encountered below grade in the excavation, the rock or softmaterials shall be removed to the specified by the Engineer and replaced with fine, granularmaterials, compacted to 95% of maximum density as determined by AASHTO T- 180.

Methods of Measurement

Pipe in place includes bedding and accepted shall be measured by the meter along the axisof the pipe.

Basis of Payment

Concrete Pipe. Pipe of several sizes, may be specified which prices and payment shallconstitute full compensation for furnishing or manufacturing; for hauling and installing the pipes;for jointing and joint materials; for excavating and backfilling; and for all materials, labor,equipment, tools and indicating necessary to complete the item.

The removal and disposal or cleaning of existing culverts as specified shall not bemeasured for payment but shall be deemed to be included in the price for the construction of newpipe culverts as provided herein.

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Reinforced Concrete PipeCulverts, diameter Line Meter (ln.m.)

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SPILLWAY STRUCTURE

Description

This item of works shall consist of cut of walls, concrete base, R.C. Pipes spaced inaccordance to the plans, top slabs and protection works for bridge approaches. Riverbankprotection and spur dikes maybe provided, however, this maybe optional. Works on this shall be inaccordance with these specifications and to the approved plans.

Material Requirements

Portland Cement - Portland Cement to be use shall be Type I. Cement samples shall beobtain in accordance to AASHTO T 1217. Different brand of Cement aside from previously testedshall not be used. Cement which has already set or which contains lumps of caked cement will berejected. Likewise, cement salvage from discarded or used bags shall not be used.

Fine Aggregates - Fine aggregates shall consist of natural sand, stone screening or otherinert materials with similar with strong and durable characteristic. It shall be washed and clean andshall have the same grading requirement as that of the work item.

Portland Cement Concrete Pavement - Beach sand not is allowed. Likewise, sand whichcontain clay and silt in greater volume shall be repeated.

Course Aggregates - Course aggregate shall consist of crashed stones, river ran gravel orother approved inert materials of similar characteristics. Grading requirement for courseaggregates shall be the same as in the Portland Cement Concrete Pavement grading “C”.

A) Boulders - Boulder to be used as base in the bottom slab shall be durable strong andclean. It shall have a maximum of 2.00 m. and not smaller than 1.00 mm. in aggregatesize.

B) Reinforcing Steel - Reinforcing steel bars to be used shall be Grade 40, with aminimum yield of fy=40,000 psi. All bars to be used shall be free rest and oils.Previously used bars shall not be used. All bars to be bent shall be done in cold bent.

C) Concrete Mix - Concrete mix to be used in this work shall be of Class “A” with aminimum compressive strength of 3,000 psi. Prior to its use, design concrete mix shallbe made including its trial mix. No concrete mix shall be use unless satisfactorylaboratory tests have been concluded.

D) Reinforced Concrete Pipes - Reinforced Concrete Pipes to be use shall be inaccordance to the size, (alienator, thickness and length).

When taken from commercial source, test certificate shall be required including acertification from the dealer of RCP – that the pipe has been previously tested.

However, one RC Pipes shall be crushed at the project site at the expense of theContractor to determine the type and size of steel reinforcement used.

Construction Methods

Controls - All vertical and horizontal controls shall be relocated and re-established by theContractor with the assistance from LGU or from the service provider hired for the sub-projects.

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The Contractor shall attempt to undertake excavation work unless the correct alignmentand elevation has been done by the Contractor in relocating vertical and horizontal control, shall beat his own risks.

A) Excavation Works - All excavation works intended for the prosecution of the worksshall be in accordance to the approved plans. Excavation works shall be true to lines,grades and elevation as indicated in the approved plan and or as directed by the ProjectEngineer.

Any over excavation done by the Contractor shall not be paid by the project.Instead, the Contractor shall restore all unnecessary excavated works back to itsoriginal position at his own expense.

In the event, the work calls for the provision of forms and other devices to providea concrete, such additional items is deemed included in other items of work and shallno paid under this item.

B) Reinforcing Steel Works - Cutting and bending of steel bars shall be in accordance tothe approved plans. No reinforcing steel bars shall be used unless it has satisfactorilypassed the required test on bending and tensile.

The Contractor shall submit to the Engineer the required Bar Bending Schedulebefore any cutting or bending shall be started. This bar bending schedule shall be thebasis of payment to the Contractor.

Steel Bars placed shall be properly fastened by Gauge # 15 tie wire. Spot weldingin lieu of tie wire fastening are not allowed as this tends to brittle the steel bars. Noconcrete pouring shall be made by the Contractor unless, steel work has beeninspected by the Project Engineer and all intersections between bars have beenfastened.

C) Concrete Works - All concrete works can only be started once the design mix has beensubmitted and the trial mix has been successful at the 7 days compressive test results.

No concrete works shall be done if forms are not properly anchored, fastened andbraced. In order to have the uniform concrete cover concrete blocks of approveddimension shall be use as spacer between the forms and the steel bars.

All concrete works shall be of Class “A” with a minimum compressive strength of3,000 Psi. For filler on the boulder voids Lean Concrete shall be use, with a minimumcompressive strength of 2,400 Psi. Batching, placing, conveying, finishing and curingof concrete mix shall be in accordance to the works as indicated the StructuralConcrete and the Portland Cement Concrete Pavement works.

D) Quality of Concrete Works - No concrete shall be deemed acceptable if no satisfactorycompressive test result have been made.

In cases where the Contractor fails to take concrete cylinder samples by his ownnegligence then such structure shall not be paid.

All concrete works or section thereof which fail to acclaim the required strengthafter the regimenting period of 28 days, shall be reflected and shall not be paid.Otherwise, the Contractor shall removed and replaced sections of the work that failed.Reduction of payment under this project is not acceptable.

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E) Reinforced Concrete Pipes - All reinforced concrete pipes to be installed shall be freefrom cracks and surface imperfections especially the inside surface of the pipes.

Distances in the installation of RC pipes shall be in accordance to the approvedplans. Tongue and grove of each pipe shall match with each other and nomisalignment shall be allowed. Strings and other means shall be use to cluck thealignment of pipes. To temporary hold the pipes in its position, concrete block shall beused.

Once the pipes are firmly set, concrete pouring shall be done in between the pipes.The concrete mix to be use shall be Class “A” with a minimum compressive strengthof 3,000 Psi. Concrete pouring shall be done simultaneous in between each pipe toavoid unnecessary movement of pipes. Wood stopper shall be at ends of row pipes tohold freshly poured concrete mix. Concrete pouring shall be done until it reaches thedesired elevation above the R.C. Pipes.

During concrete pouring operations workers shall not be allowed to walk over therows of installed R.C. Pipes in order to prevent unnecessary movement.

F) ITEM 201- Item 201 shall be use as conclusion between the concrete covering of R.C.Pipes and the top slab the spillway.

The purpose of item 201 material is to act as conclusion that will reduce theimpact to be carried by R.C. Pipes.

Works on this section shall be in accordance to the requirement of item 201 underthis project.

No payment shall be made to the Contractor unless the necessary Field DensityTest (FDT) has been complied with satisfactorily.

G) Portland Cement Concrete Paving - Prior to any concrete pouring works for the topslab of the structure, works under item 201 has been complied with in accordance tothe specifications.

Likewise, all steel reinforcement needed such temperature bars and main bars arein placed secured and properly fastened with each other.

All concrete works under this Item shall be in accordance to the work as describein the herein scope for Portland Cement Concrete Paving.

Methods of Measurement

Reinforced Concrete Pipes Culverts (RCPC) – shall be paid per linear meter installedcorrespondingly with its physical test as describe herein.

Concrete Works – shall be paid including other subsidiary works such as form works,provision of concrete blocks and other items need to complete the execution of the works. Paymentshall be in cubic meter poured with is corresponding satisfactory test results. Classes of Concreteshall be paid separately.

Reinforcing Steel Works – payment for steel works shall be on the basis of the actualquantity of Reinforcing steel placed by the Contractor. No allowance will be made to tie wires,separators, wire chains and other materials for fastening reinforcing steel in place. If the Contractorinsist to provide more steel bars in describe in the plan, such excess bars shall not be paid.

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Likewise, no measurement or payment will be made for splices added by the Contractorfor his convenience. Under this item of works the Contractor shall be paid in kilograms.

Item 201 – the Contractor shall be paid in cubic meters. This includes the cost of finishingthe materials, labor and equipment use in the work. Payment to the works done shall only be madeupon the satisfactory test results.

Excavation Works – Payment of all excavation works shall be in cubic meters excavated inaccordance to the approved plans and specification. Allowance for form works and working shallnot be paid.

Basis of Payment

Description of Work Measurements

1. Concrete Class “A” Cu.m.2. Lean Concrete Cu.m.3. Reinforcing Steel Kgs.4. R.C. Pipes Installed Lin. Meter5. Item 201 Cu.m.6. Excavation Works Cu.m.

Road Specifications (1)

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Transcript of Road Specifications (1)