混凝土面板堆石坝的面板抗裂可靠度研究-岩土工程学报.DOC

砂土中大直径单桩水平受荷离心模型试验 朱 斌1,2，熊 根1,2，刘晋超3，孙永鑫1,2，陈仁朋1,2 (1. 软弱土与环境土工教育部重点实验室（浙江大学），浙江 杭州 310058；2. 浙江大学岩土工程研究所，浙江 杭州 310058； 3. 广东省电力设计研究院，广东 广州 510000) 摘 要：E-mail：binzhu@zju.edu.cn。Centrifuge modelling of a large-diameter single pile under lateral loads in sand ZHU Bin1, 2, XIONG Gen1, 2, LIU Jin-chao3, SUN Yong-xin1,2, CHEN Ren-peng1, 2 (1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China; 2. Institute of Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China; 3. Guangdong Electric Power Design Institute, Guangzhou 510000, China) Abstract: Large-diameter pile foundations are more and more widely used in ocean engineering. The current p-y curve approach given in the API code cannot be used for large-diameter piles subjected to lateral loads. To deal with this problem, the behaviors of large-diameter piles in sand under lateral static and cyclic loadings are investigated based on several centrifugal model tests. The calculation approach for lateral displacement of pile shaft and soil reaction force using the measured bending moment of the pile shaft is verified. Static p-y curves of large-diameter piles in both dry and saturated sands are also obtained. By modifying the initial stiffness of p-y curves, a series of hyperbolic p-y curves are adopted to compute internal force and deformation of large-diameter piles. The change of deformation and internal force of large-diameter pile foundations under one-way cyclic loading is released. The test results show that the head displacement and the maximum moment of pile shaft almost linearly increase logarithmically with number of cycles. Finally the cyclic p-y curves of large-diameter pile foundations according to bending moment of the pile shaft in each cycle are obtained. A cyclic degradation factor related to the cyclic stress ratio and a corresponding approach for analyzing cyclic deformation and internal force of the pile shaft are proposed. Ke