三峡水库蓄水完成后,水对土体的软化作用会对库岸岩土的物理力学性质产生重大影响,不仅将影响到库岸边坡本身的稳定性,必然对边坡上建筑桩基的承载力和沉降变形也会产生影响,尤其是175m水位以下的建筑桩基础。但目前水库蓄水对桩基的影响研究非常少见,这给蓄水后建筑地基的承载力的复核与评估带来了极大不便。在三峡库岸边坡现场,设置了2根大直径试桩,采用基桩承载力自平衡测试技术,对基桩浸水前后的承载力、侧摩阻力、端阻力进行了系统测试,并基于试桩的测试结果,对桩浸水前后的承载力、沉降变化情况进行分析:
Being weakened by water at rock and soils changed greatly the physical and mechanical properties in Three Gorges reservoir region since the reservoir began to store, the weakening phenomena not only affect the stability of reservoir slope but also impact on the bearing capacity and settlement deformation of building pile foundation, especially those foundations which below 175 m reservoir water level. However, at present, the study of reservoir water level fluctuation on the bearing capacity are rare, it will bring inconvenience to the recheck and evaluation of the bearing capacity of saturated soil foundations. Two large - diameter test piles were set up in Three Gorges reservoir region, the before and after soaking parameters of bearing capacity, lateral friction, tip resistance of piles were detected systemicly by self - balanced method. Moreover, based on the test results, bearing caDacitv, settlement and bearing characteristic before and after soaking were analyzed.