Published Online: 1 July 2013
Page Count: 12
State Key Laboratory of Hydroscience and Engineering, Tsinghua Univ., Beijing,
Assistant Engineer, Beijing Urban Engineering Design and Research Institute Co., Ltd., Beijing,
Senior Engineer, China Institute of Water Resources and Hydropower Research, Beijing,
(Received 17 July 2012; accepted 20 March 2013)
The use of large-diameter piles as foundations for offshore wind-driven generators has become increasingly common in recent years. These piles are usually located in saturated soft clay and experience a wide variety of static and dynamic loads. A new approach was described to simulate different types of loads on a large-diameter pile under high g levels in centrifuge model tests by simplifying the complex horizontal load combinations to which such a pile is typically subjected. A series of centrifuge model tests was conducted to assess the influence of several factors. An image-based measurement system, together with a transducer-based measurement, was used to obtain a comprehensive understanding of the response of the soil. The horizontal load-induced bending moment of the pile exhibited a nearly triangular distribution. A critical load, which can be estimated as approximately half of the ultimate load, was found to exist, beyond which the rate of displacement of the pile increased significantly with increasing load. The pile-induced deformation of the soil, concentrated within zones on both sides of the pile, gradually increased as the load increased and became nearly constant when the load was close to the ultimate load. Significant separation occurred between the pile and the neighboring soil in the upper part of the pile. The critical and ultimate loads of the pile were significantly dependent on the behavior of the soil in the upper layer, the depth, and the diameter of the pile.
Paper ID: JTE20120234