变截面桩竖向承载特性的数值模拟研究

以变截面桩为研究对象,采用FLAC3D对其竖向承载特性进行了数值分析,在分析中考虑了变截面桩的几何尺寸和土层分布的影响。研究结果表明:变截面桩中扩径部分的直径与未扩径部分的直径的比值δ越大,变截面桩的竖向极限承载力逐渐增大;变截面处接近桩顶时的竖向极限承载力比接近桩底时小;当扩径部分的长度逐渐增加时,变截面桩的竖向极限承载力逐渐增大;当变截面部分所处的土性为粘质土、变截面部分以下桩体所处的土性为砂土时,变截面桩的竖向极限承载能力明显高于相反的情况。

NUMERICAL SIMULATION OF VERTICAL BEARING BEHAVIORS OF PILE WITH VARIABLE CROSS-SECTION

Take pile with variable cross-section as subject of study,the numerical analysis of its vertical bearing behaviors was done by using FLAC3D,and the effects of pile’s geometry and soil’s distribution were considered.The results show that the vertical bearing capacity of pile with variable cross-section will increase with the value ofδwhich is the diameter ratio between the expanded part and the un-expanded part.The vertical bearing capacity when the expanded part approaches to the top of pile is smaller than that when the expanded part approaches to the end of pile.The vertical bearing capacity of pile with variable crosssection will increase with increasing length of the enlarged diameter portion.The vertical bearing capacity of pile with variable cross-section when the expanded part is in clay soil and the below part is in sand is higher than the opposite.