筋箍碎石桩复合地基桩土应力比及沉降计算

摘要

深入研究筋箍碎石桩复合地基受力变形机理，考虑碎石桩桩身在荷载作用下的弹塑性变形，利用胡克定律与摩尔库伦弹塑性材料的剪胀特性，同时引入可考虑埋深效应的桩间土围限力与径向位移的折线模型，从而提出了不同荷载水平下，筋箍碎石桩复合地基加筋段与非加筋段桩身受力与变形的关系，并基于分层总和法，提出了筋箍碎石桩主管泥土应力比与沉降计算方法。最后，通过以工程算例验证了方法的合理性，并探讨了筋材刚度与荷载水平对桩土应力比的影响，结果表明加筋套筒有效增加了碎石桩的刚度，桩土应力比随荷载的增大，呈先增大后减小的趋势。%This paper considered the elasto-plastic deformation of geosythetic-encased Stone Col-umn,using the Hooke's law and the shear dilatancy character of elasto-plastic material of Mohr-Coulomb theory,and bringing in the broken-line model which could consider the buried depth effect of confined force and radial displacement between pile and soil at the same time,then put forward a computing meth-od of stone-encased column’s pile-soil stress ratio and settlement.Finally,validating the rationality of this method through to the engineering examples,and investigating the effect of reinforcement stiffness and horizontal load on the pile-soil stress ratio.The results show that the reinforcement sleeve is effective to increase the stiffness of the gravel pile,the pile-soil stress ratio increases with the load.