软土地基钻孔灌注桩受力性状分析

The Endurance of Bored-cast-in-place Piles in Soft Soil Foundations

通过对冲孔灌注桩和旋挖灌注桩桩顶、桩端沉降量静载试验资料及桩身应力应变测试资料的分析,得出桩身荷载传递机理及不同施工工艺在不同荷载水平下桩的受力性状差异,并就影响桩侧摩阻力的因素进行深入探讨。这一研究表明:桩周土的性质、桩土相对位移、桩端沉渣、成孔时间、护壁清孔方式及加载反力装置均会对单桩极限承载力产生重要影响。

By analyzing the displacement of pile top and pile bottom of the bored-cast-in-place piles, and analyzing the stress and strain of these piles, the endurance of these piles under different load-ing levels is studied, and the factors which affect the side resistance also are further discussed in this paper. Abnormal phenomena in ultimate bearing capacity of bored piles is mainly attributed to construction factors, such as soil characteristics, the relative displacement of pile and soil, pile bottom sediments,drilling time, bore retaining and cleaning, and equipment of loading counter-pressure.