大厚度回填土地层基桩受力特征试验分析  

Test Analysis on Stress Characteristics of Foundation Pile in Large Thickness Backfill Layer

作　　者：王雅君[1] 通瑞生 徐子东[1] 薛维俊[1] 乔峰[1] 

机构地区：[1]内蒙古电力勘测设计院有限责任公司,呼和浩特市010020

出　　处：《勘察科学技术》2015年第1期15-18,51,共5页Site Investigation Science and Technology

摘　　要：内蒙古西部某电厂地基土为平整场地而形成人工回填土,为防止回填土产生不均匀沉降采用桩基础。该文对经强夯处理大厚度回填土中基桩受力特征进行试验分析,得出结论：经分层强夯回填的砂岩回填土中,采用干作业旋挖成孔灌注桩工艺是可行的;单桩竖向抗压承载力特征值和水平临界荷载值均满足设计要求;经强夯处理后砂岩回填土其极限侧摩阻力值提高为80-140k Pa,不存在负摩阻力;分层夯实回填土其夯实最佳密实程度位于每层中间部位,该位置处地基土侧摩阻力最大。The foundation soil is used for artificial backfill for land leveling in a power plant in west of Inner Mongolia. In order to prevent uneven settlement of the backfill,the pile foundation is used. The stress characteristics of foundation pile in the large thickness backfill which is treated by dynamic compaction are tested and analyzed. The conclusion shows it is feasible by using dry rotary drilling pile technology in the layered compacted sandstone backfill. The characteristic value of the vertical compressive bearing capacity and the level critical loading valu of single pile are all meet to the design requirements.The value of ultimate side friction resistance of sandstone backfill increases to 80 k Pa - 140 k Pa after dynamic compaction,the negative friction resistance doesn＇t exist. The best dense degree position of layered compacted backfill is the middle part of each compacted layer,the vaule of side friction resistance of foundation soil is maximum in this position.

关 键 词：回填土 基桩 侧摩阻力 桩身轴力 

分 类 号：TU473.1[建筑科学—结构工程]