现浇混凝土薄壁管桩内摩阻力的数值分析

Numerical simulation of inner frictional resistance of cast-in-situ concrete thin-wall pipe pile

现浇混凝土薄壁管桩(简称 PCC 桩)技术是河海大学自主开发研制的用于地基加固处理的新技术,它是一种适合于软土地区的新型高效优质桩型。在全面介绍了 PCC 桩非线性有限元分析模型的建立过程后,对 PCC 桩的内摩阻力进行了计算分析。分析结果表明,土塞底部的水平应力在荷载作用过程中有较大的提高,相应位置的内摩阻力达到极限值,内摩阻力沿土塞呈指数曲线分布。同时,对内摩阻力分布规律的主要因素影响也进行了分析,给出了相应的简化计算公式。

Cast-in-situ concrete thin-wall pipe pile(PCC) is a new ground improvement technology developed independently by Hohai University, this new pile style is suitable for soft areas. The FEM model of PCC pile is introduced in detail. The results of finite element analysis show that the horizontal stress at the bottom of the soil plug increased obviously, and the inner frictional resistance achieved the limited value at the corresponding depth. The distribution of the inner frictional along the soil plug can be simulated as an exponential expression. The main factors are also studied. Based on the results, a simplified formula is obtained to calculate the inner frictional resistance.