Pressuremeter Method for Single Piles Subjected to Cyclic Lateral Loads in Sand

摘要

A method is proposed to predict the response of piles in sand subjected to cyclic horizontal loading on the basis of cyclic pressuremeter tests. This method is an extension of the pressuremeter method proposed for piles subjected to monotonic horizontal loading. The pressuremeter-derived monotonic P-y curve is reduced by a multiplier 1/N(to the a power) to obtain the cyclic P/N(to the a power)-y curve. The parameter a is obtained readily from cyclic pressuremeter tests. This pressuremeter method was used to predict the response of: 1) a 10.75-in.-diam pipe file embedded in 0.5 ft of sand and subjected to two-way cyclic horizontal loads with full reversal of loading; and 2) 12 model pile tests in sand subjected to one-way and two-way cyclic horizontal loads. A data base of full-scale cyclic horizontal load tests was also analyzed. Results show that 1) two-way cyclic horizontal loading of piles in sand leads to minimal if not negligible degradation; 2) one-way cyclic horizontal loading of piles in sand leads to significant degradation; 3) the proposed method predicts with very good accuracy the degradation of piles in sand subjected to one-way cyclic horizontal loads; but cannot predict the degradation (or lack of it) of piles in sand subjected two-way cyclic horizontal loads because the pressuremeter is a one-way cyclic test. Keywords: Cohesionless soils; Pile structures. (edc)