Technical Specification Slope Protection Works at Gumain Bridge Pier Nos. 5 and 6

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ases Conversion Development Authority

SUBIC-CLARK-TARLACEXPRESSWAY

SLOPE PROTECTION WORKS AT GUMAINBRIDGE (PIER 5 AND 6)

TECHNICAL SPECIFICATIONS

JANUARY 2O14

SUBIC-CLARK-TARLAC EXPRESSWAYSlope Protection Works at Gumain Bridge (Pier 5 and 6)

BIDDING DOCUMENTS

TECHNICAL SPECIFICATIONS

INTRODUCTION

The Technical Specifications describe in detail the work to be executed, the character andquality of materials and workmanship and the specific responsibilities of the Contractor thatare not covered by the Conditions of Contract. The Technical Specification shall be read inconjunction with the plans and other contract documents.

Pertinent notes appearing in the Contract Plans or Drawings shall also be considered as partand parcel of the technical specifications. Such notes shall take precedence over the DPWHStandard Specifications and the Supplemental Specifications.

The Supplemental Specifications shall consist of modifications and additions to the DPWHStandard Specifications (Volume II), to adapt the latter to actual conditions and/orrequirements relative to this project. Some of these modifications and additions may actuallybe of general application but in the absence of a supplemental specifications adopted byDPWH, subsequent to the publication of the DPWH Standard Specifications, 2004 Edition,Volume II @ Highways, Bridges and Airports these Supplemental Specifications have beenincluded in the Technical Specifications of this project.

The Supplemental Specifications for this project shall consist of modifications and additionalto the DPWH Standard Specifications as follows:

(1) Modifications in the specification of standard work items under Part A to Part H of theDPWH Standard Specifications. These modifications are carried out withoutchanging the "number" and "name" of each of such standard work items.

(2) Specifications for additional items of work, respectively Part A to Part H of the DPWHStandard Specifications.

The Special Provisions for this project shall consist of specifications for work Itemsdistinguished by placing the symbol "SPL" before its designated Arabic Number.

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EARTHWORK

PART C

EARTHWORK

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EARTHWORK

PART C EARTHWORK

ITEM 100 CLEARING AND GRUBBING

100.1 Description

Section 100.1 is revised to read as follows:

This Item shall consist of the removal, hauling, and stockpiling of all materials includingtrees, stumps, roots, vegetations, logs, wastes, debris and protruding objects exceptthose that are designated to remain in accordance with other items of theseSpecifications and where directed by the Engineer. The holes resulting from grubbingoperations, where directed by the Engineer, shall be filled with approved materials whichshall be placed and compacted to the same dry density as that of the adjoining soil.

100.2 Construction Requirements

100.2.1 General

Atthe end of Sub-Section 100.2.1, add the following paragraphs:

Clearing shall be extended to one (1) meter beyond the toe of the fill slopes, or roundingcut slopes or outside edge of drainage facilities, unless otherwise shown on theDrawings or directed by the Engineer, with the exception of trees under the jurisdictionof the Forest Management Bureau and/or such tree and brush designated forpreservation. Trees, shrubs or bushes designated to remain in place shall be carefullytrimmed as directed by the Engineer and shall be protected from scarring, debarking andother injuries during construction operations.

Any unauthorized interference and damage to private property shall be made good orrestored by the Contractor to the satisfaction of the Engineer and the Owner.

100.3 Method of Measurements

Delete the text of Section 100.3 and replace with the following:

Measurement will be by Area Method. The work to be paid for shall be based on thetotal area cleared and grubbed which is calculated in hectares within the limits definedon the drawings or as directed by the Engineer including adjustment that may be madeto satisfy certain site requirements.

100.4 Basis of Payment

Add the following paragraph after the first paragraph and amend the secondparagraph of Section 100.4 to read as follows:Pay Items 100, Clearing and Grubbing shall be paid in hectares and shall include thecost of removing all trees.

Amend the second paragraph of Section 100.4 to read as follows:Payment will be made under:

Pay Item Number Description Unit of Measurement

100 Clearing and Grubbing Hectare

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ITEM 103 STRUCTURE EXCAVATION

103.1 Description

Add the following paragraphs to Section 103.1:

Structure excavation shall include the furnishing and placing of approved foundation fillmaterials to replace unsuitable materials encountered below the foundation elevations ofthe structures.


103.2.2 Excavation

Add the following paragraphs to Sub-Section 103.2.2:

Any excavation carried beyond the limits and dimensions as shown or described on theDrawings or Specifications shall be backfilled with acceptable materials.

The sides of pits, trenches and other excavations shall, where required, be adequatelytimbered and supported at the satisfaction of the Engineer, and all such excavationsshall be sufficient size to enable the concrete to be laid accurately and proper refillingand compaction to be carried out.

Should excavations be effected to a greater depth or width than is necessary then theContractor shall at his own expense backfill the excess excavation with approvedmaterials, compacted to the density of the adjacent ground, to the correct levels anddimensions to the approval of the Engineer.

When instructed by the Engineer, the Contractor shall carefully set aside the variousmaterials encountered so that they may be replaced in their original position.

Trenches shall be kept clean and free from water during excavation, concreting, andbackfilling, and the Contractor shall dig diversion channels, erect cofferdams orotherwise de-water the trench.

Where, in the opinion of the Engineer, any invert has become soft or unsuitable toreceive the concrete bed due to the Contractor's method of working, the Contractor shallat his own expense remove and replace the material with non-structural concrete orother approved material as instructed by the Engineer. Where concrete is specified, themix shall consist of ordinary Portland cement and aggregate, both complying with theSpecifications Item 405. The weight of cement mixed with 0.3m3 of aggregate shall notbe less than 50 kg. The quantity of water shall not exceed that required to produce asmooth cement paste, which coat evenly the whole of the aggregate.

The Engineer's approval is required before placing concrete in all excavations forstructures made through water bearing strata that require dewatering.

103.2.6 Backfill and Embankment for Structures Other than Pipe Culvert


EARTHWORK

Add the following paragraph to Sub-Section 103.2.6

Foundation fill and backfill for structures other than pipe culvert shall be granular sub-base materials meeting the requirements of Item 200 and complying with the grading ofTable 200.1

Delete the text of Sub-Section 103.3.4 and substitute the following:

Shoring, cribbing, and related protective works if required in the construction shall not bemeasured and paid for separately and shall be considered subsidiary to the item forwhich they are constructed and utilized.

103.3.5 Basis of Payment

Delete the second sentence of Sub-Section 103.3.5 including items (1), (2), (3) and(4) and substitute the following:

The payment for structure excavation and bridge excavation shall be deemed to includethe cost of backfilling, shoring, cribbing, protective works, removing and disposingunsuitable materials off site and removal and hauling of excess suitable materials tostockpiles as directed by the Engineer. The payment shall be the full compensation forthe work item including the cost of labor, equipment, tools and incidentals necessary tocomplete the work prescribed in this item.

No measurement for separate payment to the Contractor shall be made for back-fillbeing the relevant compensation included by the Contractor in his rates in the Bill ofQuantities in the pay items for excavation for structures and bridges.

Replace the second paragraph of Sub-Section 103.3.5 with the following:

Payment will be made under:


103 Structure Excavation Cubic Metre

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ITEM 104 EMBANKMENT

104.2 Material Requirements

Add the following item at the end of the Sub-Section 104.2:

Selected Granular Embankment

The materials to be used for embankment at the back of Cribwall shall be selectedgranular embankment-river run gravely sand or gravel or other clean granular materialsas shown and specified on the drawing or as directed and approved by the Engineer.


104.3.1 General

Add the following paragraph at the end of Sub-Section 104.3.1

Prior to the construction of embankment, the Contractor shall submit for review andapproval the methodology he intends to apply for the formation of embankmentsatisfying all requirements in conformity with the lines, grades and dimensions shown inthe plans. The methodology shall show the systematic procedure of constructing theembankment in conjunction with the procedure proposed for the slope protection asshown in the drawings.

The approval of the proposed methodology however does not relieve the Contractor ofthe responsibilities for any unsatisfactory or defective works as results of suchmethodology. The Engineer at his discretion may reject or require remedial measures tothe defective works. The cost of replacing or remedying defective works shall be borneby the Contractor.

104.3.2 Method of Construction

Embankment/Backfilling activities shall be phasing parallel with the sequence ofCRIBWALL construction. Each layer of embankment/backfill shall not be more than500mm thick and shall be properly compacted with compaction equipment inaccordance with this Specifications. The process is repeated until the whole height of theretaining wall is filled.

104.4 Method of Measurement

Add the following paragraph after the last paragraph of Sub-Section 104.4:

Any material coming from roadway, structure, drainage or ditch excavations which aresuitable for use but are replaced by the Contractor with borrow materials without priorapproval by the Engineer, shall not be measured for payment.

Measurement of quantities for embankment shall be made by the volume ofembankment materials placed and compacted to the lines, grades, and dimensionsshown on the drawings or directed by the Engineer and shall be taken only in thepresence of the Engineer. The Engineer shall be notified at least 24 hours before takingsuch measurement. The volume of embankment materials shall be computed by endarea method and determined from the excavation section of the embankmentestablished on the original ground line after stripping. The original ground line shall be

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EARTHWORK

surveyed and reported to the Engineer for checking and approval to the execution of theembankment operation.


Modify the text of Section 104.5 to read as follows:

The accepted quantities, measured as prescribed in Section 104.4, shall be paid for atthe Contract unit price for the Pay Items listed below that is included in the Bill ofQuantities. The payment for accepted quantities for embankment with fill materials fromroadway and borrow excavation shall be deemed to include the cost of excavation,hauling, blending, drying and wetting if necessary, placing, spreading and compactionof fill materials. The payment for accepted quantities for embankment construction withfill materials from dredging and realignment of river channel and structure excavationshall be deemed to include the cost of hauling from stockpiles, blending, drying andwetting if necessary, placing, and spreading and compaction of fill materials. Thepayment shall be full compensation for the furnishing, placing and compacting of allmaterials, including all labor, equipment, tools and incidentals necessary to complete thework prescribed in this Item.

The unit price shall also include the costs for procurement and furnishing of requiredmaterials if not coming from approved excavation. No separate payment shall be madefor the tentative removal of embankment, counterweight fill, placing and removal ofsurcharge and preload and secondary excavation and backfilling for structures to beconstructed on the embankment, cost of which shall be deemed included in the unitprice of the embankment.



104 Embankment (Selected Fill or Granular Cubic MetreRiver Run)


IIII

I

DRAINAGE AND SLOPE PROTECTION STRUCTURES

II PART G

DRAINAGE AND SLOPEPROTECTION STRUCTURES

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DRAINAGE AND SLOPE PROTECTION STRUCTURES G

PART G DRAINAGE AND SLOPE PROTECTION STRUCTURES

ITEM 404 REINFORCING STEEL404.3 Construction Requirements

At the end of Sub-Section 404.3.1 insert the following:

The Contractor shall, before materials are ordered, furnish the Engineer for approval plansof the reinforcement arrangement of each affected structure showing clearly any revisedspacing or diameters of bars required to ensure that the design strength of the structure ismaintained. For the purposes of this Sub-section, design strength shall be define as theproduct of yield strength of reinforcing bar and the area of reinforcing bar provided in thesection. Any expense incident to the revisions of materials furnished in accordance withsuch plans shall be borne by the Contractor.

Supplement this Section with following:

404.3.7 Rebar Fabrication and Installation

Rebar fabrication and installation shall be done by a competent steel man to ensure goodworkmanship. There should be a proper supervision for the "cutting and bending" ofreinforcing bars, frequent checking of bar schedule and clearances, from the beginning untilthe re-bars are installed.

404.3.8 Bar Bending, Splicing and Placing

The Contractor shall submit to the Engineer for approval, the shop Drawings Indicating thebending, cutting, splicing and installation of all reinforcing bars.


Supplement this Section with the following:

The quantity to be paid for shall be the calculated theoretical number of kilograms ofreinforcing steel bars, mesh or mats as determined from the net length of the steel asshown on the drawings, incorporated in concrete and accepted. Reinforcing steel bars shallnot be measured and paid separately where structures are paid in unit, as they are deemedto be included in the unit pay items of the structures.

The weight of plain or deformed bars or bar-mat information to AASHTO Specifications willbe computed from the theoretical weight of plain round bars of the same nominal size asshown on the following table:

Bar Size Unit WeightDesignation (mm) (kg/m)

#2 6 0.222#3 10 0.616#4 12 0.888#5 16 1.579#6 20 2.466#8 25 3,854#9 28 4.833#10 32 6.313#11 36 7.991

Bidding DocumentsSpecifications

BarDesignation

#2#3#4#5#6#8#9#10#11

Subic-Clark-TarlacExpressway'SlopeProtectionatGumainBridge(Pier5and6)

Size(mm)

61012162025283236

DRAINAGE AND SLOPE PROTECTION STRUCTURES G_




404 Reinforcing Steel (Grade 40) Kilogram

ITEM 405 STRUCTURAL CONCRETE

405.1 Description

405.1.2 Classes and Uses of Concrete

The whole text under this Sub-section is amended as follows:

Two (2) classes of concrete are provided for in this item, namely A, A1 and lean. Each classshall be used in that part of the structure as described herein below and called for on thePlans.

The classes of concrete are as follows:

Class A - For reinforced concrete Cribwall and as indicated on the Plans.

Class A1 - For Slab on Fill and where shown on Plans.

Lean Concrete- For thin layers underneath footings and where shown on Plans or asdirected by the Engineer.

405.2 Materials Requirements

405.2.3 Coarse Aggregates

Modify Table 405.1 as follows:

405.2.6 Admixtures

405.3 PRODUCTION REQUIREMENTS

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Bidding DocumentsSpe cificat ions

SieveDesignationStandard

(mm)6350

3-752519

12.59.5

4.75

AlternateU.S.Std

254"

21 V?

1

%3/8

No.4

MassPercentPassingC L A S S

A

10090-100

-20-550-10

A1

100-

40-700-15

LEAN

10095-100

-25-60

_0-10


405.3.1 Proportioning and Strength of Structural Concrete

Modify Table 405.2 as follows:

Table 405.2 a Composition and Strength of Concrete for use in Structures(Locally Manufactured Cement)

Based on 40 kg/bag

After the last Subsection under this Section, add the following Sub-section:

405.3.2 Protection of Concrete from Environmental Conditions

1. General

Precaution shall be taken as needed to protect concrete from damage due to weather orother environmental conditions during placing and curing operations. Concrete that hasbeen damaged by weather conditions shall be either repaired to an acceptable condition orremoved and replaced.

2. Rain Protection

Under conditions of rain, the placing of concrete shall not commence or shall be stoppedunless adequate protection is provided to prevent damage to the surface mortar ordamaging flow or washing of the concrete surface.

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ClassesofConcrete

A

A1

Lean

MinimumCementContent

Kg(bag**)

360(9bags)

360(9.0bags)

320(8bags)

MaximumWater/Cement

Ratio

Kg/kg

0.49

0.49

0.54

ConsistencyRangeinSlump

mm(inch)

50-100(2-4)

50-100(2-4)

50-100(2-4)

DesignatedSizeofCoarse

Aggregate

SquareOpeningStd.

25-4.75

(T'-No.4)

19-4.75

(1/2*-No.4)

37.5-4.75

(1 %"-No.4)

MinimumCompressiveStrength of150x300 mmConcreteCylinderSpecimen @28days

N/mm2(psi)

21(3000)

21(3000)

17(2500)


3. Hot Weather Protection

When the ambient temperature is above 32 C (90 F), the forms, reinforcing steel, steelbeam flanges, and other surfaces which will come in contact with the mix shall be cooled tobelow 32 C (90 F), by means of a water spray or other approved methods.

The temperature of the Concrete at the time of placement shall be maintained within thespecified temperature range by any combination of the following:

Shading the materials areas or the production equipment.

Cooling the aggregates by sprinkling with water which conforms to therequirements.

Cooling the aggregates or water by refrigeration or replacing a portion or all themix water with ice that is flakes or crushed to the extent that the ice willcompletely melt during mixing of the concrete.

405.4

Liquid nitrogen injection

Method of Measurement

The whole text under this section is amended to read as follows:

The quantity of structural concrete, reinforcing steel, formworks and falseworks required forcast-in-place concrete construction or other Contract Pay Items shall be measured forpayment in the manner prescribed in the several items involved.

No separate measured shall be made for formwork for Class A Concrete.


The whole text under this section is amended to read as follows:

The accepted quantities measured as prescribed in Section 405.4, Method of Measurement,shall be paid for at the contract unit price for each of the several pay items listed below thatare included in the Bill of Quantities. The price and payment shall be full compensation forfurnishing, preparing, fabricating, placing, curing and for all labor, equipment, tools andincidentals necessary to complete the Item.

Payment for Class A concrete shall be deemed to include the cost of formwork.


Pay Item Number Description

405

405(1)

Concrete Concrete Class A - Cribwall(fc=21.0 Mpa)

Concrete Concrete Class A1 - Slab on Fill(fc=28.0 Mpa)

Unit of Measurement

Cubic Meter

Cubic Meter

405(2) Lean Concrete (fc=15 Mpa) Cubic Meter

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Bidding Boatmen.Specificatior


ITEM 502 MANHOLES, INLETS AND CATCH BASINS

Modify this section to read as follows:

5021 DescriptionThis item shall consist of the construction, reconstruction or adjustment of lined ditch and catch basins inaccordance with this Specification and in reasonably close conformity with the lines and grades shown onthe Plans or as established by the Engineer.

502.2 Material RequirementModify this section to read as follows:Unless otherwise indicated on the Plans, Concrete for these structures shall be ConcreteClass "A" and shall be in accordance with item 405, Structural Concrete.

502.3 Construction RequirementsConcrete construction shall conform to the requirements for Item 405-Structural Concrete.Metal frames shall be set in full mortar bed. When grade adjustment or existing structures

is specified, the frames, covers and gratings shall be removed and the walls reconstructedas required. The cleaned frames shall be reset at the required elevation. Upon completion,each structure shall be cleaned of any accumulation of silt, debris, or foreign matter of anykind and shall be kept clear of such accumulation until final acceptance of the work.Excavation and backfill shall be done in accordance with Item 103, Structure Excavation.

502.4 Method of MeasurementModify this section to read as follows:

Lined ditches and catch basins, both new and reconstructed as applicable, will be measuredby the unit. Any additional concrete, reinforcing steel required for authorized increases inheights of structures paid of under this Item and in excess of the standard height shown onthe Plans will be measured and paid for under Item 405, Structural Concrete and Item 404,Reinforcing Steel, as applicable. Structures noted on the Plans as "junction boxes" will bemeasured for payment as manholes. The number of concrete covers, pairs of metal frames

and gratings, and pairs of metal frames and covers will be measured as acceptablycompleted. The number of lined ditches and catch basins adjusted as directed will bemeasured as acceptably completed.


The accepted quantities, determined as provided in Section 502.4, Method of Measurementof the Pay Items in the Bill of Quantities will be paid for at the contract unit prices, whichshall constitute full compensation for furnishing and placing all materials and for all labor,equipment, tools and incidentals necessary to complete the Item. Excavation and backfill willbe measured and paid for as provided in in item 103 Structure Excavation.

Modify this section to read as follows:Payment will be made under:

Pay Item No. Description Unit f Measurement

502(2) Lined Ditch Inlet (U-Ditch) Llnear Meter

502(3) Catch Basin (1.4x1.5m) each

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ITEM 505 RIPRAP AND GROUTED RIPRAP

505.1 Description

Modify this Section to read as follows:

This Item shall consist of furnishing and placing of riprap with grout in accordance with thisSpecification and to the lines, grades and dimensions shown on the Drawings. The workalso include construction of weep holes.



505.2.1 Stones

Stones for riprap shall be hard, durable, bank or river stones, resistant to weather action andfree from seams or other defects. The stones for grouted riprap Class "A" shall be roundnatural stones of sizes ranging from 200 mm @ 300 mm in diameter as shown on theDrawings. Adobe stones and lime rocks shall not be used for riprap works.

505.2.2 Filter Material at Weep-hole

Polyester non-woven plastic cloth, sewed like a bag and filled with 20 mm gravel will beused as filter material at each weep-hole as shown on the Drawings.

505.2.3 Mortar

Mortar for grouted riprap shall be one (1) part cement to three (3) parts sand by volume andenough water to obtain the required consistency and shall conform to the requirements ofItem 405, Structural Concrete.



505.3.1 Excavation

The bed for grouted riprap shall be excavated to the required depths of Cribwall foundationas shown on the Drawings.

The grouted riprap shall be founded at the toe of Cribwall as shown on the Drawings or asordered by the Engineer.

505.3.2 Placing

The stones shall be laid by hand or individually by machines. They shall be laid with dose,broken joints and shall be firmly bedded into the slope and against the adjoining stones.Each stone shall be laid with adjacent stones. The grouted riprap shall thoroughly berammed into place as construction progresses and the finished surface shall present aneven, tight surface. Interstices between stones shall be filled with small broken fragmentsfirmly rammed into place. The spaces between the stones shall then be filled with cementmortar as specified in Sub-section 504.2.3. Sufficient mortar shall be used to completely fillall voids, except that the face surface of the stones shall be left exposed.

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505.3.3 Grouting

Grout shall be place from bottom to top of the surface swept with a stiff broom. Aftergrouting is completed the surface shall be cured as specified in Item 405, StructuralConcrete for a period of at least three days. Hardened grout left during the previous days'operation shall be cleaned thoroughly from earth or dust and other unnecessary materialswith water and broom before another layer of stone and grout is added.



Riprap and grouted riprap shall be measured by the cubic metre in place, completed andaccepted by the Engineer in accordance with the Drawings. Only accepted work will bemeasured for payment and the computation of the quantity thereof will be based on thevolume within the limiting dimensions designated on the Drawings.


This Section is entirely deleted and substituted with the following:

The quantities measured as provided under Sub-section 504.4, Method of Measurementshall be paid for at the Contract unit price as listed in the Bill of Quantities, which price andpayment shall be full compensation preparation of the bed, for furnishing and placing allmaterials including all labor, equipment, tools and incidentals necessary to complete thework item.



505(1) Grouted Riprap, Class A Cubic Metre

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ITEM 506 STONE MASONRY


506.2.1 Stone

The first and second paragraph shall be modified with the following:

Stones shall be clean, hard and durable and shall be subject to the approval of theEngineer. Unless otherwise specified on the Drawings or directed by the Engineer, stonesfor masonry shall be Class A as described in Item 504, Riprap and Grouted Riprap. Stonesmore or less will have roughly similar blunted ends.

506.2.2 Mortar

Add at the end of this Sub-section with the following:

The binder for stone masonry shall be mortar Class A and composed of one (1) partPortland cement and two (2) parts of sand by volume and shall conform to the requirementsof materials under Item 405, Structural Concrete. Mortar that is not used within 90 minutesafter water has been added shall be discarded. Retampering of mortar will not be permitted.



506.3.1 Excavation

The bed for stone masonry shall be excavated to the required depths of Cribwall foundationas shown on the Drawings.

The stone masonry shall be founded at the toe of Cribwall as shown on the Drawings or asordered by the Engineer.

506.3.2 Placing

The stones shall be laid by hand or individually by machines. They shall be laid with close,broken joints and shall be firmly bedded inside the beam opening of Cribwall. Each stoneshall be laid with adjacent stones. The stone masonry shall thoroughly be rammed intoplace as construction progresses and the finished surface shall present an even, tightsurface. Interstices between stones shall be filled with small broken fragments firmlyrammed into place. The spaces between the stones shall then be filled with cement mortaras specified in Sub-section 505.2.2. Sufficient mortar shall be used to completely fill allvoids, except that the face surface of the stones shall be left exposed.

506.3.3 Grouting

Grout shall be place from bottom to top of the surface swept with a stiff broom. Aftergrouting is completed the surface shall be cured as specified in Item 405, StructuralConcrete for a period of at least three days. Hardened grout left during the previous days'operation shall be cleaned thoroughly from earth or dust and other unnecessary materialswith water and broom before another layer of stone and grout is added.

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Stone Masonry shall be measured by the cubic meter in place, completed and accepted bythe Engineer in accordance with the Drawings. Only accepted work will be measured forpayment and the computation of the quantity thereof will be based on the volume within thelimiting dimensions designated on the Drawings.


This Section is entirely deleted and substituted with the following:

The quantities measured as provided under Sub-section 505.4, Method of Measurementshall be paid for at the Contract unit price as listed in the Bill of Quantities, which price andpayment shall be full compensation for preparation of the bed, for furnishing and placing allmaterials including all labor, equipment, tools and incidentals necessary to complete thework item.



506 Stone Masonry Cubic Meter

ITEM 507 RUBBLE MASONRYThis item shall consist of the construction of rubble concrete around footing base of Gumain Bridge Pier No.5 in accordance with this specification and in conformity with the lines, grades, slopes and dimensionsshown in the Plans or established by the Engineer.

507.2Material Requirements

507.2.1StoneThe stone shall be cleaned, hard, and durable and shall be subject to the Engineer's approval. Adobe stoneshall not be used unless otherwise specified. Stones to be used shall be more than 0.015 cubic metre involume and not less than 75 percent of the total volume of rock embankment and shall consist of stones0.03 cubic metre in volume as described in Item 506.2. Stones obtained from excavation performed underthis contract may be used.

507.2.2Concrete Class "B"

Concrete shall be Class "B in accordance with Item 405, Structural Concrete.

507.3Construction Requirements

507.3.1 Preparation of Foundation Bed

The foundation bed shall be excavated to the lines and grades as shown in the plans as directed by theEngineer, and shall be thoroughly compacted in accordance with Item 104.3.3.

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507.3.2Falsework and Formwork Construction

Falsework/formwork shall be constructed so as to withstand the stresses imposed. Formwork used shall tieconstructed with sufficient strength, rigidity and shape as to leave the finished works true to the dimensionsshown on the Plans and with the surface finished as specified. The inside surface of the forms shall becleaned of all dirt, water and foreign materials. Forms shall be thoroughly coated with form oil prior to use.The form oil shall be commercial quality form oil or other approved coating which will permit the readyrelease of forms and will not discolorthe concrete.

507.3.3PlacingOne layer of concrete Class "B* shall be placed at the prepared bed prior to placing of stones. Clearancebetween stones shall not be less than 2-1/2inches or the maximum size of concrete aggregate for Class"B". Concrete Ctass "B" shall be placed after each layer of stone and shall be thoroughly consolidated bymeans of a vibrator inserted in each layer of concrete. In no case shall the vibrator be operated longer than10 seconds in any location. After removal of forms, any cavities, voids and honeycomb spots shall be filledup with mortar composed of one part cement and two parts sand. All debris and refuse resulting from workshall be removed and the site left in a neat and presentable condition.

507.3.4Weephotesit shall conform to the requirements of Item 505, Riprap and Grouted Riprap under Subsection 505.3.4,Weepholes.

507.4Method of MeasurementThe quantity to be paid for shall be the number of cubic meters of rubble concrete complete in place andaccepted. In computing the quantity of payment the dimension used shall be those shown on the plans orordered in writing by the Engineer. No reduction shall be made forweepholes.

507.5Basis of PaymentThe quantity of rubble concrete determined as provided in the preceding section 507.4, Method ofMeasurement, shall be paid for at the contract unit price per cubic meter for rubble concrete, which price andpayment shall be full compensation for the preparation of the bed, furnishing, necessary excavations,falsework, and for all labor, equipment, tools and incidental necessary to complete the Item.

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I

I

Paymentwillbemadeunder

PayItemNumber

507

Description

RubbleConcrete

UnitofMeasurement

CubicMeter


ITEM 511 GABIONS

511.1 Description


"This works shall consist of constructing wire-mesh gabions, furnished, place and filled inwith rocks in accordance with the Specifications and at the locations and in conformity withthe lines and grades shown on the plans or as ordered by the Engineer"


511.1.1 General

511.1.2 Wire

Supplement this Subsection with the following:

Unless otherwise specified on the plans, the minimum size of wire for gabions shall be asfollows:



"The quantities to be measured shall be the number of cubic meter of gabions, placed,completed and accepted.



Quantities determined as provided under Section 511.4 Method of Measurement shall bepaid for at the appropriate contract unit price per unit of measurement of the pay itemsshown in the Bill of Quantities, which price and payment shall constitute full compensationfor all necessary excavation, subgrade preparation, for furnishing, placing of wire basketsand fill materials and for all labor equipment, accessories, tools and incidentals necessary tocomplete the item.

Payment will be made under:Pay Item Number Description Unit of Measurement

511(1) Gabions Cubic Meter

511(3) Geotexiiles (Filter Cloth) Square Meter

Subic-Clark-Tarlac Expressway Bidding DocumentsSlope Protection at Gumain Bridge. (Pier 5 and 6) Specifications

Wire

BodyWireSelvedgeorperimeterwireTyingandconnectingwire

Diameter(mm)Gabions

2.7

3.4

2.3


Add the following work item to Part G ofDPWH Standard Specifications

ITEM SPL-A TEMPORARY COFFERDAM DURING CONSTRUCTION

SPL-A.1 Description

This item shall consist of furnishing and placing of materials to prevent seepage or the entryof river water during construction works at the bridge's pier in accordance with thisSpecification and the Drawings.

Prior to the construction of the temporary cofferdam, the Contractor shall submit a shop-drawing showing its dimensions based on actual ground condition together with hisproposed methodology and sequence of operation to the Engineer for the laser's fullsatisfaction and approval.

SPL-A.2 Material Requirements

This item shall consist of grouted rockfill materials, should be impervious enough to resistthe seepage of water from the river, and constructed in accordance with this Specificationsand to the lines, grades and dimensions as shown on the Plans. Rockfill materials to beused shall conform to Item 505. Mortar for the grouted rockfill shall be Class "A".

SPL-A.3 Construction Requirements

The materials for the cofferdam shall be placed in close conformity with the lines, grades,and dimensions as shown on the drawings or as directed by the Engineer. It should be soconstructed to withstand the strong impact and scouring action of the river in times offlooding while the construction works at the bridge's pier is ongoing.

The stones shall be laid by hand, or individually by machine. The spaces between thestones shall be filled with cement mortar sufficiently to completely fill all the voids.

SPL-A.4 Method of Measurement

The quantity to be measured and paid for shall be the number of cubic meter of materials inplace, completed and accepted by the Engineer and shall constitute such materials asspecified in Item SPL-A.2

SPL-A.5 Basis of Payment



SPL-A Temporary Cofferdam Cubic Meter

Subic-Clark-Tarlac Expresnvay Bidding DocumentsSlope Protection at Gumain Bridge (Pier 5 and 6) Specifications


Add the following work item to Part G ofDPWH Standard Specifications

ITEM SPL-B RIVER RE-CHANNELING DURING CONSTRUCTION

SPL-B.1 Description

Realignment of river channel shall consist of excavation, removal and trimming of all classesof materials in the channel prism including placing or stockpiling of excavated suitablematerials and disposal of unsuitable or surplus materials to designated disposal areas inaccordance with these Specifications and Drawings or as directed by the Engineer.

Prior to re-channeling works, the Contractor shall submit a shop-drawing showing itsdimensions (length, width, height) based on actual ground condition together with hisproposed methodology and sequence of operation to the Engineer for the latter's fullsatisfaction and approval.

SPL-B.2 Construction Requirements

Excavation for river re-channeling shall be done in close conformity with the lines, grades,and dimensions as shown on the drawings or as directed by the Engineer.

Excavated materials from river re-channeling works shall be stockpiled at the designatedarea by the Engineer.

SPL-B.3 Method of Measurement

River channel excavations will be measured by volume in cubic meter of material excavatedfrom the channel prism to the neat lines and grades as shown on the Plans and asestablished by the Engineer.

Hauling of excavated materials either for stockpiling or disposal including trimming of sideslopes in channel prism and channel bed shall be considered subsidiary works under thisitem.

Provision and maintenance of access roads, detour roads, temporary bridges and drainagesand crane ways to construction site shall not be measured and paid for separately and shallbe deemed to be included in the related pay Items prescribed in these specifications.

SPL-B.5 Basis of Payment



SPL-B River Re-channeling Cubic Meter

Subic-Clark-Tarhc Expressway Bidding DocumentsSlope Protection at Gumain Bridge (Pier 5 and 6) Specifications

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Subic-Clark-Tarlac ExpresswaySlope Protection at Gumain Bridge (Pier 5 and 6)


Technical Specification Slope Protection Works at Gumain Bridge Pier Nos. 5 and 6

Documents

Transcript of Technical Specification Slope Protection Works at Gumain Bridge Pier Nos. 5 and 6