湿陷性黄土地区桩筏基础与地基共同作用研究

Study on Interaction between Pile-raft Foundation and Soil in Slumping Loess Area

桩筏基础中的筏板将分担一定的荷载 ,分担百分比因受诸多因素的影响难以量化 ,且筏底土反力、桩顶荷载如何分布的问题目前尚处于研究阶段 ,而这些却是影响桩筏基础设计的主要因素。通过对湿陷性黄土地区某高层建筑所进行的原位测试 ,得出筏板与其下基土之间存在接触压力 (即筏底土反力 ) ,群桩与筏板共同承担建筑物总荷载 ,本工程筏板分担 2 8.6 %。

The raft in pile-raft foundation shares some load of a building and what percentage of load it shares is difficult to quantify due to the influence of couples of factors. Besides, how to distribute soil pressure under the raft and load on the heads of piles is still a problem under research. All these are primary factors affecting the design of pile-raft foundation. Through in-situ test for one high-rise building in a slumping loess area, it is concluded that contact pressure (soil pressure under the raft) exists between the raft and its foundation soil, and that pile group and raft together undertake the gross load of a building, with the raft of this project sharing 28.6% of the load.