水平荷载下扩底楔形桩承载力特性透明土模型试验

发布时间：2018-07-08 13:53

本文选题：扩底楔形桩 + 水平荷载　；参考：《土木工程学报》2015年05期

【摘要】：通过改变纵向截面形式以提高单位材料利用率、提高桩侧摩阻力或桩端阻力的异形桩在工程界逐步得到推广应用;然而,针对纵向截面形式改变对基桩水平向承载力特性影响的研究却相对较少。为分析纵向截面形式改变对水平向承载特性影响规律及桩-土相互作用机理;基于透明土材料和PIV(particle image velocimetry)技术,采用非插入式测试方法开展水平荷载作用下扩底楔形桩的承载力特性模型试验,测得水平荷载下基桩H0-y0曲线、基桩变形、以及桩周土体扰动位移场等规律特性,继而探讨水平荷载下扩底楔形桩的极限承载力、基桩变形对桩周土体位移场的扰动规律以及桩-土相互作用机理;同时进行等截面桩、楔形桩的水平向承载力特性透明土模型试验作为对比分析。试验结果表明,文中试验条件下,由于扩大头的存在,扩底楔形桩的水平向承载力约为楔形桩的2.0倍;水平荷载下,桩周土体的竖向位移略比水平向位移要大,桩端附近土体水平向位移变化比竖向位移变化要更明显;水平极限荷载下桩端略有一点向上拔出。
[Abstract]:By changing the form of longitudinal section to improve the utilization ratio of unit material, the special-shaped pile which increases the friction of pile side or the end of pile is gradually popularized and applied in engineering circles; however, However, there is little research on the influence of the change of longitudinal section form on the horizontal bearing capacity of foundation pile. In order to analyze the influence of the change of longitudinal section form on the horizontal bearing characteristics and the pile-soil interaction mechanism, based on the transparent soil material and (particle image velocimetry) technology, In this paper, the bearing capacity characteristic model test of the expanded wedge pile under horizontal load is carried out by using the non-insertion test method. The H0-y0 curve of the foundation pile under horizontal load, the deformation of the foundation pile, and the disturbance displacement field of the soil around the pile are measured. Then, the ultimate bearing capacity of the expanded wedge pile under horizontal load, the disturbance law of the deformation of the foundation pile to the soil displacement field around the pile and the pile-soil interaction mechanism are discussed. The horizontal bearing capacity of wedge pile is analyzed by model test of transparent soil. The test results show that the horizontal bearing capacity of the bottom wedge pile is about 2.0 times that of the wedge pile, and the vertical displacement of the soil around the pile is slightly larger than that of the horizontal displacement under the horizontal load due to the existence of the enlarged head. The change of horizontal displacement of soil near the pile end is more obvious than that of vertical displacement, and the pile end is pulled out slightly upward under the horizontal limit load.
【作者单位】：河海大学岩土力学与堤坝工程教育部重点实验室;河海大学土木与交通学院;重庆大学;
【基金】：国家自然科学基金(51278170) 高速铁路基础研究联合基金(U1134207)
【分类号】：TU473.1

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