【摘要】 孔隙水压力变化规律是饱和粉土体宏观变形细观结构研究的基础。以阳光新城工程为例,采用现场试验方法对长螺旋CFG桩施工时的孔隙水压力(简称孔压)变化进行了监测,并根据监测结果对施工过程的孔隙水压力(简称孔压)变化进行了阶段划分。研究结果,长螺旋CFG桩施工过程中孔压变化规律与常规的剪切液化观点相悖,抽吸与窜孔对孔隙水压力变化影响显著,并解释了产生这种现象的原因。孔压极大值和极小值在一定范围内产生累加效应,表现为非对称性,而变化的幅度值呈近似对称性。根据幅度值大小确定了长螺旋CFG桩施工时的影响范围,其值与小孔扩张理论比较吻合。更多还原

【Abstract】 Variation of pore water pressure is the microstructure foundation of saturated clay’s macro-deformation. Taking the Yangguang Xincheng project for example, pore water pressure was monitoring during the construction of long spiral CFG pile on site; and then summarized the variation of pore water pressure. According to the law of pore water pressure changes, CFG pile construction is divided to several stages. The results show that the variation of pore water pressure conflicts with conventional point of shear liquefaction; pump and fleeing bore influence pore water pressure obviously; and then the reasons for this phenomenon are given. The maximum and minimum values of pore water pressures have has accumulation effect, which performances non-symmetry along a pile construction, but amplitude of pore pressure change assumes approximate symmetry. Based on the amplitude of pore water pressure, the sphere of CFG pile construction influence is determined; and its value is relatively consistent with the cavity expansion theory’s result.更多还原