带帽有孔管桩复合地基荷载传递特性分析

Analysis on load-transfer characteristics of composite foundation of pipe pile with cap and holes

为探索带帽有孔管桩复合地基荷载传递特性,对带帽无孔管桩复合地基和三种开孔方式的带帽有孔管桩复合地基进行了模型试验和数值模拟,研究了各桩型复合地基荷载沉降、桩身轴力、桩周土压力、桩土荷载分担比和桩土应力比等承载性状。试验结果验证了桩身开孔能让超孔隙水主动进入管桩内腔,从而降低土体含水量,提高土体抗剪强度,更有利于发挥桩土体分担荷载的作用,减小复合地基总沉降,以及提高复合地基承载力。研究成果能为有孔管桩复合地基理论研究提供基础,并对其应用推广和优化设计起指导作用。

In order to study the load transfer characteristics of the composite foundation of pipe pile with cap and holes,the model test and numerical simulation were carried out on pipe pile composite foundation with cap as well as pipe pile composite foundation with cap and holes( with three kinds of hole opening styles). The bearing behaviors such as load settlement,pile axial force,pile surrounding soil pressure,pile-soil load sharing ratio and pile-soil stress ratio were studied. The test results verify that the opening of the pile body allows the super-porous water to actively enter the inner cavity of the pipe pile,thereby reducing the water content of the soil and improving the shear strength of the soil,which is more conducive to the role of the pile-soil sharing load and the reduction of the total settlement of the composite foundation and increase the bearing capacity of the composite foundation. The research results can provide a basis for the theoretical study of composite foundation of pipe piles with cap and holes,and provide guidance for its application and optimization design.