Case studies of dynamic load testing in Japan

This paper reviews 69 cases of dynamic load testing performed in Japan on a commercial basis since 1983, and points out some subjects, such as 'set-up' phenomena and hammer driving energy, to be considered in the interpretation of the dynamic load test signals, in order to make the dynamic load test a more useful tool in the design, quality assurance and driving control of piles. The Japanese Association for Steel Pile Piles (JASPP) conducted their own dynamic load tests on a total of 13 steel pipe piles at different site conditions, the results of which are compared with the static load test results. This paper also presents the results of these comparative tests, emphasizing that adequate conditions for the dynamic load test are required to derive accurate estimations of the static load-displacement curve, as well as ultimate pile capacity, from the dynamic load test.