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Acceptance Testing and Mitigation <br /> Vertical inspection pipes for acceptance testing shall be provided in all cast-in-drilled-hole concrete piles that are <br /> 600 mm in diameter or larger,except when the holes are dry or when the holes are dewatered without the use of temporary <br /> casing to control ground water. <br /> Inspection pipes shall be Schedule 40 polyvinyl chloride pipes with a nominal inside diameter of 50 mm. Each <br /> inspection pipe shall be capped top and bottom and shall have watertight couplers to provide a clean,dry and unobstructed <br /> 50-mm diameter clear opening from 1.0 in above the pile cutoff down to the bottom of the reinforcing cage. <br /> If the Contractor drills the hole below the specified tip elevation, the reinforcement and the inspection pipes shall be <br /> extended to 75 mm clear of the bottom of the drilled hole. <br /> Inspection pipes shall be placed around the pile, inside the outermost spiral or hoop reinforcement, and 75 mm clear of <br /> the vertical reinforcement,at a uniform spacing not exceeding 840 mm measured along the circle passing through the centers <br /> of inspection pipes. A minimum of 2 inspection pipes per pile shall be used. When the vertical reinforcement is not bundled <br /> and each bar is not more than 26 mm in diameter,inspection pipes may be placed 50 mm clear of the vertical reinforcement. <br /> The inspection pipes shall be placed to provide the maximum diameter circle that passes through the centers of the inspection <br /> pipes while maintaining the clear spacing required herein. The pipes shall be installed in straight alignment,parallel to the <br /> main reinforcement, and securely fastened in place to prevent misalignment during installation of the reinforcement and <br /> placing of concrete in the hole. <br /> The Contractor shall log the location of the inspection pipe couplers with respect to the plane of pile cut off, and these <br /> logs shall be delivered to the Engineer upon completion of the placement of concrete in the drilled hole. <br /> After placing concrete and before requesting acceptance tests, each inspection pipe shall be tested by the Contractor in <br /> the presence of the Engineer by passing a 48.3-mm diameter rigid cylinder 610 mm long through the complete length of pipe. <br /> If the 48.3-mm diameter rigid cylinder fails to pass any of the inspection pipes, the Contractor shall attempt to pass a <br /> 32.0-mm diameter rigid cylinder 1.375 in long through the complete length of those pipes in the presence of the Engineer. If <br /> an inspection pipe fails to pass the 32.0-mm diameter cylinder, the Contractor shall immediately fill all inspection pipes in <br /> the pile with water. <br /> The Contractor shall replace each inspection pipe that does not pass the 32.0-mm diameter cylinder with a 50.8-mm <br /> diameter hole cored through the concrete for the entire length of the pile. Cored holes shall be located as close as possible to <br /> the inspection pipes they are replacing and shall be no more than 150 mm inside the reinforcement. Coring shall not damage <br /> the pile reinforcement. Cored holes shall be made with a double wall core barrel system utilizing a split tube type inner <br /> barrel. Coring with a solid type inner barrel will not be allowed. Coring methods and equipment shall provide intact cores <br /> for the entire length of the pile concrete. The coring operation shall be logged by an Engineering Geologist or Civil Engineer <br /> licensed in the State of California and experienced in core logging. Coring logs shall include complete descriptions of <br /> inclusions and voids encountered during coring, and shall be delivered to the Engineer upon completion. Concrete cores <br /> shall be preserved, identified with the exact location the core was recovered from within the pile, and made available for <br /> inspection by the Engineer. <br /> Acceptance tests of the concrete will be made by the Engineer, without cost to the Contractor. Acceptance tests will <br /> evaluate the homogeneity of the placed concrete. Tests will include gamma-gamma logging. Tests may also include <br /> crosshole sonic logging and other means of inspection selected by the Engineer. The Contractor shall not conduct operations <br /> within 8.0 in of the gamma-gamma-logging operations. The Contractor shall separate reinforcing steel as necessary to allow <br /> the Engineer access to the inspection pipes to perform gamma-gamma logging or other acceptance testing. After requesting <br /> acceptance tests and providing access to the piling,the Contractor shall allow 3 weeks for the Engineer to conduct these tests <br /> and make determination of acceptance if the 48.3-mm diameter cylinder passed all inspection pipes,and 4 weeks if only the <br /> 32.0-mm diameter cylinder passed all inspection pipes. Should the Engineer fail to complete these tests within the time <br /> allowance,and if in the opinion of the Engineer,the Contractor's controlling operation is delayed or interfered with by reason <br /> of the delay in inspection, the delay will be considered a right of way delay as specified in Section 8-1.09, "Right of Way <br /> Delays,"of the Standard Specifications. <br /> All inspection pipes and cored holes in a pile shall be dewatered and filled with grout after notification by the Engineer <br /> that the pile is acceptable. Placement and removal of water in the inspection pipes shall be at the Contractor's expense. <br /> Grout shall conform to the provisions in Section 50-1.09, "Bonding and Grouting," of the Standard Specifications. The <br /> inspection pipes and holes shall be filled using grout tubes that extend to the bottom of the pipe or hole or into the grout <br /> already placed. <br /> If acceptance testing performed by the Engineer determines that a pile does not meet the requirements of the <br /> specifications,then that pile will be rejected and all depositing of concrete under slurry or concrete placed using temporary <br /> casing for the purpose of controlling groundwater shall be suspended until written changes to the methods of pile <br /> construction are approved in writing by the Engineer. <br /> The Contractor shall submit to the Engineer for approval a mitigation plan for repair, supplementation, or replacement <br /> for each rejected cast-in-drilled-hole concrete pile,and this plan shall conform to the provisions in Section 5-1.02,"Plans and <br /> Working Drawings," of the Standard Specifications. Prior to submitting this mitigation plan,the Engineer will hold a repair <br /> Contract No. 10-OM7104 <br /> 166 <br />