of hammer, number of operating blows per minute, piston area, and effective piston pressure to be maintained to COR for approval. Do not begin piledriving operations until earthwork fills have been completed or excavations have reached an elevation of 150 to 300 mm (6 to 12 inches) above bottom of footing or pile cap. Provide proper anvil and cushion to prevent pile butt damage. Cap or cushion block to consist of one solid block of hardwood of proper shape and dimensions to fit hammer. Block grain to be parallel to pile axis. If laminated materials are used, strength of such materials to be equal to or greater than hardwood. Continuous or frequent introduction of materials to cushion hammer blows will not be permitted. Do not use wood chips, small blocks, shavings, or similar materials to cushion hammer blow. Driving piles through overburden without COR prior approval will not be permitted. Drilling, spudding, or jetting is acceptable only when approved by COR and performed at no additional cost to the Government. Methods employed will be subject to COR approval. Final 1500 mm (5 feet) of pile penetration must be obtained with hammer alone. Predrilling: Provide preexcavated holes for piles driven within 4500 mm (15 feet) of existing structures or underground utilities, to depths indicated on drawings. Drill hole diameter less than the largest crosssection dimension of pile. Firmly seat pile in predrilled hole by driving with reduced energy before starting final driving. Heaved Piles: Redrive heaved piles to tip elevation at least as deep as original tip elevation with driving resistance at least as great as original driving resistance. Drive foundation piles to bearing stratum and driving resistance established by test piles. If allowable capacity is not obtained in bearing stratum, drive piles deeper until required driving resistance is obtained. Penetration of all piles in a group should not vary more than 3000 mm (10 feet) unless approved by COR. Make no penetration measurements for purpose of determining resistance to driving when pile heads are damaged to extent that may affect measured penetration nor immediately after fresh cushion block has been
of hammer, number of operating blows per minute, piston area, and effective piston pressure to be maintained to COR for approval. Do not begin piledriving operations until earthwork fills have been completed or excavations have reached an elevation of 150 to 300 mm (6 to 12 inches) above bottom of footing or pile cap. Provide proper anvil and cushion to prevent pile butt damage. Cap or cushion block to consist of one solid block of hardwood of proper shape and dimensions to fit hammer. Block grain to be parallel to pile axis. If laminated materials are used, strength of such materials to be equal to or greater than hardwood. Continuous or frequent introduction of materials to cushion hammer blows will not be permitted. Do not use wood chips, small blocks, shavings, or similar materials to cushion hammer blow. Driving piles through overburden without COR prior approval will not be permitted. Drilling, spudding, or jetting is acceptable only when approved by COR and performed at no additional cost to the Government. Methods employed will be subject to COR approval. Final 1500 mm (5 feet) of pile penetration must be obtained with hammer alone. Predrilling: Provide preexcavated holes for piles driven within 4500 mm (15 feet) of existing structures or underground utilities, to depths indicated on drawings. Drill hole diameter less than the largest crosssection dimension of pile. Firmly seat pile in predrilled hole by driving with reduced energy before starting final driving. Heaved Piles: Redrive heaved piles to tip elevation at least as deep as original tip elevation with driving resistance at least as great as original driving resistance. Drive foundation piles to bearing stratum and driving resistance established by test piles. If allowable capacity is not obtained in bearing stratum, drive piles deeper until required driving resistance is obtained. Penetration of all piles in a group should not vary more than 3000 mm (10 feet) unless approved by COR. Make no penetration measurements for purpose of determining resistance to driving when pile heads are damaged to extent that may affect measured penetration nor immediately after fresh cushion block has been
316200DrivenPiles.docx