Method Statement for Road Works (道路施工方案英文)
METHOD STATEMENT FOR ROAD WORKS
TABLE OF CONTENTS
1.0 SCOPE
The purpose of this Method Statement is to describe the Methodology involved in construction of Road Works in accordance with project technical specifications, international standards and codes, local rules and regulations (QCS-2010). This method statement will cover the following works:
Earth Works Preparation to Road Formation
Granular Sub-base Preparation Works
Asphalt Works
2.0 PERMITS AND LICENSES
The Permits and License required for commencement of the work shall be obtained prior starting any site activities, the permits and license shall be obtained from the Following:
Electricity and Water Authority
Tel-communication Operator
Municipality Government
Ministry of Environment
Public Work Authority (Roads)
3.0 SEQUENCE OF WORKS FOR ROADS
3.1 Site preparation
Prior to commencement of work, the contractor shall obtain the relevant work permits from Client
The contractor shall under take clearing of site in order to remove any existing vegetation; steel, concrete, unused buildings identified for demolition, piping debris, loose windblown sand and other foreign materials.
All existing structures, foundations, etc. as indicated above shall be entirely demolished, removed, transported and disposed of by the contractor to a debris yard designated by Client. All soft spots left shall be filled with suitable material and compacted as per
specification.
Excavated material, if any, and suitable and approved by Client for backfilling shall be transported and placed in fill areas within the limits of the work.
3.2 Survey and Setting Out
3.2.1 Survey Markers
Survey Markers shall be durable, appropriate to location and intended use.
Survey Markers shall be clearly identifiable and protected from construction traffic. For installation of a Survey Marker into reinforced concrete, the JV's will ensure that steel reinforcement bars are to be avoided.
Either removable anchors or epoxy adhesive shall be used as the methods of fixing Benchmarks are a particular type of Survey Markers used in the control of elevation.
Benchmarks shall have a domed surface for unambiguous staff placement. Primary Benchmarks shall comprise a stainless steel bolt securely placed vertically into a
concrete slab, or horizontally into a column.
The protrusion shall not pose a safety hazard. Survey Markers used for horizontal control shall have an unambiguous point above (or below) which a survey instrument can be precisely centered.
The point shall comprise either a punch mark or the intersection of 2 lines forming a cross. Cross-headed road nail (75mm long) complete with a colored washer shall
generally be used as a Survey Marker.
3.2.2 Control Observation, Adjustment and Presentation
Homogeneous horizontal and vertical survey control is required prior to any setting out.
Survey control shall evolve from the whole to the parts. Where practical, all survey points within a horizontal survey control network shall be occupied and observed from.
Forced centering techniques shall be used throughout. A round of angular observations shall comprise the mean of observations taken on both faces of the total station. A minimum number of 4 rounds of horizontal and vertical angles shall be observed at each instrument set up.
For control work, the angular spread of horizontal angles shall not exceed 3‘‘ of arc.
Distances shall be measured in both directions. All raw data pertaining to each set up shall be electronically recorded. Survey control shall include redundant observations.
Observation networks shall be processed using the method of least squares
adjustment and the resulting residuals to the observations shall be inspected for
magnitude.
Any large residuals or error ellipses shall be examined and appropriate remedial action shall be taken. Precise leveling shall be double run using equal back and fore sights at each instrument set up. Leveling sights shall never exceed 30 meters. On the ground surface, the Contractor shall establish stable bench marks adjacent to the site so that
Height datum transfer accuracy shall be better than 2mm in a 30m deep shaft. The transfer of height datum shall be by various independent means. azimuth transfer from surface to underground shall be better than 3― of arc and point transfer shall be
accurate to within 2mm. Such transfers shall be by various independent means.
At 3 month intervals, the Contractor shall conduct a complete survey of all existing survey control. A bound, A4 size survey control report shall be submitted to the
Engineer for acceptance within 2 weeks of completing the field work.
The convention adopted shall comprise Station Name, Easting, Easting, Northing and Elevation reading from left to right report shall contain the following information report shall contain the following information: dates of survey, fixed survey control and values, specification of instrumentation used, calibration status of instrumentation used,
observational acceptance criteria, list offinal adjusted co-ordinates findings and
conclusion.
Attached to the report shall be the observations (A4 print out of electronic booking sheet or customized spread sheet), adjustment with residuals and station error ellipses, table of differences in mm from previous co-ordinates and elevations (if applicable),a drawing clearly showing layout of scheme and measured quantities and final co-
ordinates in tabular form.
3.2.3 General Setting Out
The Contractor shall carry out a comprehensive level survey of the Contract area before any work commences on the site that may alter original ground levels.
Pre-computation shall be carried out prior to any setting out. For rail projects, the effects of cant and throw shall be incorporated into pre-computation wherever relevant.
All pre-computation shall be readily available in a spread sheet format for use on site.
The method of setting out for each particular element of the work shall commensurate with the required accuracy, the method of construction, and shall be appropriate for site conditions.
In the setting out process, all elevation transfer conducted by leveling shall start on an established benchmark and finish on a different benchmark. If a significant disclosure is detected, the reason shall be determined and the necessary corrective action taken.
After the erection of the formwork and prior to concreting, a survey check shall be carried out on the formwork to ensure that the setting out has been done correctly.
A spreadsheet shall be used in all instances to tabulate the difference (or offset) in mm
between the actual set out (or as-built) co-ordinates from the design co-ordinates. In cases where the design is an alignment, offsets to the alignment shall be computed for each surveyed point.
3.3Earth Works
3.3.1Earthwork General
The JV will carry out all earth work in such a manner as to prevent erosion or slips and shall limit working faces to safe slopes and height.
The JV will ensure that all surfaces have at all times sufficient gradients to enable them to shed water without causing erosion.
Hauling of material from cuttings or the importation of fill material to the embankments or other areas of fill shall proceed only when sufficient compaction plant is operating at the place of deposition to ensure compliance with the requirements of Client.
Construction traffic other than that required for the excavation and trimming shall not use the surface of the bottom of a cutting unless the cutting is in Rock or the Contractor maintains the level of the bottom surface at least 300 mm above formation level.
Any damage to the sub-grade arising from such use of the surface shall be made good by the Contractor at his own expense with material having the same characteristics as the material which has been damaged.
The JV will arrange for the rapid dispersal of water shed on to the earth works or completed formation during construction, or which enters the earth works from any source
The JV will provide where necessary temporary water courses, ditches, drains, pumping or other means of maintaining the earth works free from water
The JV will take special care that naturally occurring materials within the site are not rendered unsuitable by his method of working. Areas of cuttings and excavation shall be so worked that rainfall is conducted rapidly away from the exposed material and at times of expected heavy rain that the cutting areas are protected by appropriate
methods of working and drainage provisions.
3.3.2Classification of Earth Work Material
The following definitions of earth works shall apply to this and other clauses of the Specification in which reference is made to the definitions:
Top Soil' shall mean the top layer of soil that can support vegetation.
Suitable Material' shall comprise all that is acceptable in accordance with the Contract for use in the works and which is capable of being compacted in the manner specified in project Technical Specifications to form a stable fill having side slopes as indicated on the drawings.
Not Suitable Material' shall mean other than suitable material and shall include :
?Material from swamps, marshes or bogs;
?Peat, logs, stumps or other organic matter and perishable and toxic materials;
?Material susceptible to spontaneous combustion.
?Clay of liquid limit exceeding 80 and/or plasticity index exceeding 55.
?Rock' shall mean hard material found in ledges or masses in its original position,
which would normally have to be loosened either by blasting or by pneumatic tools, or if excavated by hand, by wedges and sledge hammers. ?Rock‘ shall also include
all solid boulders or detached pieces of rock exceeding 0.10 m 3 in size in trenches
or exceeding 0.20 m 3 in general excavation.
3.3.3 Excavation
Excavation will be carried out to the dimensions, lines, levels and slopes as indicated on the IFC Drawings.
If the JV excavates deeper than the depths shown on the Drawings or as instructed by the Client, then he shall fill in such excessive depths with acceptable materials to the satisfaction of the Client.
The bottom of all excavations shall be free from mud and water, trimmed clean, protected from the effects of weather and thoroughly compacted and consolidated
The JV will be responsible to excavate to the top of soft or defective soil below the formation level and backfill with Suitable Material. Such backfill will be well compacted in layers of accepted thickness by approved manners and means.
3.3.4Cuttings and Cut Slopes
Unless otherwise specified, no portion of the earth cutting shall vary from the specified or ordered formation level by an amount exceeding 150mm.
In the case of cut slopes, no portion of the completed slope shall vary by an amount exceeding 100mm (measured at right angles to the slope).In all cuttings, whether in earth or rock, undulations in the general plane of the slope will not be permitted.
Unless otherwise specified, excavation in rock shall extend to at least150mm below the specified formation level and backfilled with approved materials.
Any overhanging, loose or unstable material shall be removed. The excavation shall be so arranged that the working areas are adequately drained throughout the period of construction.
In cutting where the strata consists of earth overlaying rock which is required to be cut to a slope of 1 (H): 2 (V) or steeper, the face of the rock shall be given its appropriate slope up to the junction of the rock and earth and the latter shall be stripped to form a bench 900mm wide and sloped to the gradient as specified.
3.3.5Maintenance of Excavated Area
Continuously monitor the dimensions / level of excavation to avoid over Cutting if any accidental over cutting takes place, fill and compact with Suitable material to the
desired level.
Remove any undesirable material (vegetation, organic soils etc.)Encountered during
excavation and fill with approved granular material.
Take necessary measures to keep the excavation free from water by De-wateringwherever required.
Arrange shoring so that it does not interfere with the progress of work and
Functioning of nearby facilities as work proceeds, remove the shoring carefully
without causingany danger to the excavation.
If any accidental slips or settlement occurs in the excavated area, Properly fill by
selected fill or with mass concrete.
3.3.6Sloping the Sides of Excavation
Wherever there are chances of sliding, properly slope sides of Excavation.
Trim the slopes by hand to uniform batters as shown on the IFC Drawings.
Trim any rock or boulder appearing in the face of the slope, and remove italtogether, if it seems unstable.
If any rock is removed, fill the resulting void with compacted material.
?Imported Rock Fill' shall be clean well-graded quarry waste provided by the Contractor from sources outside the Site. It shall be resistant to weathering, to the acceptance of the Client.
The maximum size particles in the material shall pass through a rigid 200mm square grid and the largest dimension of any particle shall not exceed 300 mm. The material shall not have more than 10% of its particles passinga0.75 mm BS sieve.
?Fill Material' shall mean Suitable Material for backfilling with the exc eption of Rock and Imported Rock Fill
?Special Fill Material‘ shall mean Suitable Material of which at least 95 per cent shall pass a 125mm BS sieve and at least 90 percent shall pass the 75mm BS sieve. Up to 5 per cent of the material may be made up from isolated boulders of maximum dimensions not exceeding half the thickness of the layer of material being placed.
Liquid limit not exceeding 35
plasticity index not exceeding 12(h) ?Selected Fill' shall be well graded granular natural sands, gravel, crushed rock, crushed concrete, well burnt shale or other
materialsaccepted by the Client. The material passing a 425 micron BS sieve, when tested inaccordance with BS 1377, shall have a plasticity index of less than 6%.
?Imported Fill Material' shall be Fill Material supplied by the Contractor from a source outside the Site and accepted by the Client's.
3.3.7 Compacting and Levelling the Fill
During compaction, maintain the M.C of fill material, usually +/- 3 Percent of OMC. If Required, add clean water to the fill material in order To maintain the necessary M.C
Achieve minimum density of specified M.D.D. of soil, by using roller / Plate compactor or any other approved equipment.
Around new (or existing remaining) concrete foundations or other Substructures do Not compact by rolling. Instead, use mechanical Rammers or plate compactors to Compact the space in vicinity of Concrete structure.
After compaction, level the surface free from undulations using suitable Equipment.
3.4 Materials forSub-base
3.4.1Fine Aggregate for Sub-Base
Fine aggregate (Passing the 4.75 mm sieve) shall consist of crushed mineral aggregate and/or natural sand.
The fine aggregate shall be clean and free from organic matter, clay — balks and other extraneous or detrimental materials.
The ratio of aggregates passing the 0.075 ram sieve shall not exceed 66% of the portion passing the 0.425 mm sieve.
The material passing the 0.425 mm sieve shallhave a maximum liquid limit of 25% and the plasticity index shall not exceed 6%.
Where the source of fine aggregate does not meet the above requirements, with the Engineer's approval, add fine aggregate and filler to correct the gradation or to change the characteristics of the material passing the 0.42 mm sieve so as to meet the requirements. Such additional material shall be added in a manner which ensures a completely homogeneous material
3.4.2Coarse Aggregate for Sub-Base
Coarse aggregate (retained on the 4.75 mm sieve) shall consist of crushed stone crushed gravel with minimum of 50% by weight having at least one fractured face.
The flakiness index of the aggregate shallnot exceed 35% when tested in accordance with BS 812.
The Los Angeles Abrasion Loss, as defined by ASTM C131/C535, shallbe 40% maximum.
The aggregate type for the sub-base shall be crushed limestone.
170-7.5.66 The coarse aggregate shall be hard and durable and free from organic matter, clay and other extraneous or detrimental materials.
Coarse aggregate shall have a maximumloss of 20% by the magnesium sulphate soundness test when performed as per ASTM C88 for 5 cycles.
The minimum CBR value obtained when preparing samples of aggregate base and aggregate Sub-base at optimum moisture content and at 100% relative
compaction and soaking them for 4 days shall be 80% and 60%; respectively. The maximum permitted swell shall he 0.5% and 1.0%; respectively
3.4.3 Mix Design for Sub-base
Aggregates sub-base shall consist of crashed mineral aggregates or natural mineral aggregates of the designated gradation and thickness.
The maximum dry density and the Optimum moisture content of the material shall ascertained as per the test procedure given in CML 12- 97 andthis shall be
used to assess the degree of compaction of the mix after rolling
The pavement layer designated as sub-base, the material shall conform to Class B or Class C
The particle size shall be determined by the washing and sieving method of BS 812: Part. 103.
Fine and coarse aggregates for sub-base shall be combined gradation of material that meets the requirements of the specification for density and other properties,
The aggregate bases shall conform to the class A or class B gradation and the aggregate sub-base shall conform to the class C gradation, as given in the following Table:
Immediately comply with such instructions without being entitled to any indemnities or extensions as a result of such instructions. Any equipment or plant shall not be used beforeobtainingthe approval of the Client and to engage skilled And trained operators, mechanics and labour to carry out the works.
3.5 Plant Generally
The machinery and tools used in constructing the various items involved in asphalt
works shall be in good workingcondition and free of oil and fuel leaks This various
items shall be maintained and preserved for the whole duration of the work. The
Client shall approve the machinery and tools before works begin and supply of such machinery with adequate quantities in order to execute the work with due speed and precision.
For the Client if required, the manufacturer's catalogues, specifications and other published data for the equipment and machinery shall be supplied.
On first erecting a batching plant and at least once each three months thereafter, the plant shall be calibrated by a calibration service organization approved by the
Central Materials Laboratory. Production shall not be permitted if the weigh batch calibration does not comply with the requirements of BS 5328.
The Client shall have the right to stop the use of any equipment or plant which he deems to be inferior to the quality required or detrimental to the permanent works and to instruct the removal of such equipment and to have it replaced by suitable equipment
Immediately comply with such instructions without being entitled to any indemnities or extensions as a result of such instructions. Any equipment or plant shall not be used beforeobtainingthe approval of the Client and to engage skilled. And .trained operators, mechanics and labor to carry out the works.
3.6 Inspection and Testing Control
For verification of plant weights and measures, character of materials used in the preparation of the mixes, testing and other quality control requirements, the Engineer shall at all times be provided access to all portions of the mixing plant, aggregate plant, storage yards, crushers and other facilities used for producing and processing the materials of construction
The Engineer shall have authority to take samples and perform tests on any material supplied to the site from any source whatsoever in order to establish compliance
andtoaccept or reject as he deems necessary. Samples shall also be taken from completedwork to determine compliance. The frequency of all sampling and testing shall be asdesignated by the Engineer.
Suitable facilities at the quarry or plant shall be provided to carry out all necessary
tests on the raw materials and mixes.
For obtaining specimens of materials and samples taken from stockpiles shall be arranged, including the provision of any necessary equipment and plant. This work shall be performed in the presence of the Engineer if so directed by the Engineer.
Materials that are not in compliance shall be rejected and removed immediately from the site of the works times otherwise instructed by the Engineer.
Where defects in the material or the completed work have been corrected, until approval has been given by the Engineer subsequent work shall not proceed.
Materials which require drying before performing any of the designated tests shall be dried out at temperatures not greater than 100 OC.
3.7Installation Procedure for Sub-base
Before commencing the construction of the sub-base, written approval for the Engineer must be obtained thatthe sub-grade is in compliance.
Before starting the sub-base all the structures have to be installed like kerbs, dropped kerbs, barrier‘s foundations, median b arriers, channel block and
gully's pre-cast concrete part with road gully pot.
If the naturalmoisture content is less than the optimum moisture content, the necessary amount of water must be added to obtain the optimum content.
Allowance shall be made for the quantity of moisture which may be lost by evaporation in the process of raking, leveling and compacting, depending on atmospheric temperature
The compacted layer shall have moisture content within. ±2% of the optimummoisture content.
The moisture content shall be uniform in all parts of the section where the work is being carried out and in the various depths of the layer thicknessCompaction shall start immediately afterthe material has been laid.
Work on the sub-base courses shall not continue during rainy weather.
Material shall be spread as 2 layers to a thickness that would result in layers not more than 150 mm thick after compaction
The course shall not be rolled when the underlying material is soft or yielding or when the rolling causes a wave like motion in this course.
When the rolling develops irregularities, the irregular surface shall be loosened, then refilled with the same kind of material as used in constructing the course and again rolled.
Rolling must continue until a relative density of not less than 100 % of the maximum dry density has been obtained as determined by the moisture density relationship in CML 12-97
Care shall be taken so that layers already compacted under the layer being executed are not damage, or that the formation is not damaged
Any such damage resulting in mixing the various layers constituting the different sub-grades and sub- base courses shall be carefully made good by our own expense and to the satisfaction of the Engineer.
Any material that fails to meet test requirements shall either be reworked or removed and replaced and then retested to check for compliance. Also the corrective actions and protection shall be done accordance with QCS section 6 parts 4.7 and 4.8.
All testing shall be can-led out in accordance with AASHTO T96, AASHTO T104 and the relevant parts of BS 1377 or CML Standard Methods of test
The sub-base shall be compacted and tested for acceptance in accordance with SML 12-97 and BS 1377 to attain a minimum density of 100 % of the maximum city density ofthe material. Two tests every 500 m2 shall be carried out unless otherwise directed bythe Engineer.
Whenever the degree of compaction is found to be less than required, the area of sub-base involved shall be satisfactorily corrected.
The gradation of the placed material shall be checked by taking samples from an area
0.5x0.5 m from the full depth of the layer for every 1000 m3 of laid material. The
gradation shall be tested in accordance with BS 812: Part 101
Wherever the gradation is found to be outside the designated limits, the area of sub-baseinvolved shall be scarified, removed or reworked to provide a gradation in
compliance.
The final surfaces of the sub-base shallbe tested by means of a 4 meter long straightedge. And no rises or depressions in excess of 10 mm shall appear inthe surface.
The finished surface shall be checked by dips or spot levels and shall be constructed to the designated grade levels to within ± 10 mm.
Where these requirements are not met, the full extent of the area which is out of tolerance shall be determined and shall make good the surface of the course by scarifying to a minimum depth of 75 mm or4 times the maximum particle size. Whichever is greater, reshaping by adding or removing material as necessary, adding water if necessary and re-compacting.
3.8 Protection of the Surface
The sub-base course shall be protected sothat it shall be maintained sound during work progress, after its completion and before receiving the bituminous layers or
before laying the surface overlay thereon.
Any damage caused to the layer if exposed to traffic or natural conditions resulting in damage to its surface shall be made good according to the satisfaction of the
Engineer.
The Engineer has the right to stop all hauling over completed or partially completed sub-base course when there is any proof such hauling is causing
damage.
Following the completion of the sub-base course, all maintenance work necessary shall be performed to keep the course in a condition for priming.
3.9 Materials for Asphalt Work
Fine aggregate is that portion of the mineral aggregate passing the 2.36 mmBS Sieve.
Fine aggregate shall be non-plastic and chemically stable.
Unless permitted elsewhere in the contract, the aggregate type for the wearing and intermediate courses shall be Gabbro.
Fine aggregate shall be clean and free from organic matter, clay, cemented particles and other extraneous or detrimental materials.
Sampling of fine aggregate shall be in accordance with BS 598 part 100.6
Fine aggregate shall be consist of crushed hard durable rock and shall be of such Gradation that it will meet the required gradation Wadi beach or dune sand won't be Used.
Individual stockpiles of crushed -fine ag g re g ate shall have a sand equivalent of not less than 30.
The loss by the magnesium sulphate soundness test, as determined by ASTM C88, shall be a maximum of 18 %
The maximum acid-soluble chloride content shall be 0.1% and the maximum acid- soluble sulphate content shall be 0.5 %.
The fine aggregate shall havea maximum plasticity index of 4 % when sampled form stockpiles and shall be non-plastic when sampled from hot bins.
3.10 Coarse Aggregate for Asphalt Work
Coarse aggregate is that portion of the mineral aggregate retained on the 2.36 mm BSSieve. Coarse aggregate shall consist of crushed natural stones and gravel. Crushedparticles shall be cubic and angular in shape and shall not be thin, flaky
or elongated.
The source of crushed aggregate is considered to the crushing site from which it is produced. Sampling of coarse aggregate shall be in accordance with BS 598 : part 100.
Coarse aggregate shall be clean and free from organic matter, clay, cemented particles and other extraneous or detrimental material The degree of crushing
shallbe such that a minimum of 99 % by weight of aggregate (each stockpile) having at least one fractured face and 85 % having at least two fractured
faces. No rounded or sub-rounded particles shall be used_ The flakiness
index (of each stockpile) shall not exceed 25 % for wearing course and 30 % for intermediate and base courses and the elongation index (of each stockpile) shall not exceed 25 % for the wearing course and 30 % for the intermediate and base courses.
The loss by magnesium sulphate soundness test, as determined by ASTM C88, shall be a maximum of 10 % for aggregate used in wearing and intermediate
courses and a maximum of 15 % for aggregate used in base course.
The Los Angeles Abrasion Loss, as determined by ASTM C131/C535, shall be a maximum of % 25 for wearing course aggregate and 30 % for intermediate and
base coursesaggregate.
The aggregate crushing value, as determined by BS 812: Part 110, shall be a maximum of 20 % for the wearing course ag g re g ate and a maximum of 25 % for the intermediate and base courses aggregate
The average water absorption by the aggregate for all courses shall not exceed 1.5 % except for base course where it shall not exceed 2.0 % when tested in accordance with BS 812
3.10Mineral Filler
Mineral filler when separately supplied from an external source shall consist of finely around mineral matter such as rock dust, hydrated lime, cement or other
material which can satisfy the Engineer will produce asphalt mixes of at least equal quality. It shall be free from organic substances and clay, shall be thoroughly dry and free from agglomerations, shall be non-plastic and shall meet the following grading requirements:
use of the hydrated limeshall at all timesbe such as to protect the material
from the weather.
When cement is used as mineral filler, it shall meet the requirements of BS 12.
3.11 Bitumen
Bitumen specified for use in the asphalt mixes shall be 60-70 penetration grade in accordance with BS 3690 and shall only be obtained from approved sources.
The bitumen shall be prepared by the refining of petroleum. It shall e uniform in character and shall not foam. When heated to 175 °C. Blending of bitumen materials from different refineries will be used only with the written approval of the Engineer.
3.12 Prime Coat Materials
Liquid asphalt for use in asphalt works shall be MC-70 medium curing cutback Asphalt in accordance with AASHTO M82.
The application rate shall be between 0.45 to 0.75 kg/m2, or as directed by the Engineer. Excessive application of prime coat shall be avoided.
The application temperature for the MC-70 liquid asphalt shall be between 60 °C and
85 °C as directed by the Engineer.
3.13 Tack Coat Materials
The emulsified asphalt for use in
asphalt works shall comply with BS
434: Part 1 class K1-40.
Alternatively emulsified asphalt for use
in asphalt works shall be CSS-11or
CRS-2Cationic emulsified asphalt in
accordance with AASHTO M208 or
SS-Ihanionicemulsified asphalt in
accordance with AASHT0
M140.uuless otherwisedesignated.
Emulsified asphalt shall be of the
slow-setting cationic or anionic type of
the CSS-IL OrSS-Ih grades respectively and shall conform to the designated requirements.
The approved emulsion will be diluted with approximately an equal quantity of
Water and thoroughly mixed as directed by the Engineer.
3.14Material Testing
In addition to these requirements a fully equipped site laboratory shall be provided or shall arrange for materials and samples to be transported to the Central
Materials Laboratory for testing
In addition suitable facilities at the asphalt botching plants shall be provided to enable the Engineer to carry out all necessary tests on the raw materials and mixes.
Such facilities will be subject to the Engineer's approval and the preparation of
asphalt mixesshall not be allowed until the facilities have been approved by the
Engineer.
3.15 Delivery, Spreading and finishing
3.15.1 Delivery of Mixes
Sufficient plant capacity, haul
vehicles and storage shall be
provided so that adequate
supplies of mixture are
delivered to site to ensure
that continuous paving can
be achieved.
The dispatching of the hauling
vehicles to the job site shall be
so scheduled that all material
delivered may be placed in
daylight, unless the Engineer
has approved the use of
artificial light. Delivery of
material shall be at a uniform
rate and in an amount well within the capacity of the paving and compacting
equipment.
All precautions shall be taken to protect
the mix from the weather during transit
and while waiting to discharge.
Hauling vehicle shall not be permitted to
carry out tight turns on the laying
surface.
The mixture at delivery to the paver
shall be within 14°C of the Job Mix
formulatemperature and above an
absolute minimum temperature of
135°C. Material which has fallen below the minimum temperature of 135°Cbefore