加筋碎石桩格栅强度设计初探

A Tentative Exploration on the Strength Design of the Geogrid in Geosynthetic-encased Stone Columns

分析了加筋碎石桩复合地基的承载机理,探讨了加筋碎石桩复合地基的2种主要破坏模式,破坏模式1由格栅套筒抗拉强度控制,破坏模式2由非加筋段桩侧土强度控制。采用极限平衡理论分别导出了两种不同的破坏模式下加筋碎石桩单桩极限承载力计算公式。基于2种破坏模式下的承载力计算公式,在加筋深度一定的情况下给出了格栅合理设计强度解析解。最后,运用本文方法对某工程实例进行计算,计算结果与实测数据吻合较好。

The bearing mechanism of geosynthetic-encased stone columns was analyzed and two primary kinds of failure modes was investigated.Failure mode 1 is mainly controlled by the strength of geogrid sleeve,and failure mode 2 is controlled by the strength of the soil along the no-reinforced section.Based on the two failure modes,the method of the limit equilibrium is employed to deduce the formulas of the ultimate bearing capacity by which,the expression of the optimal design strength of the geogrid is presented in this paper.At last,when the method was used to analyze the practical project,its feasibility was proved by the reasonable agreement between the calculated and the measured values.