开孔管桩复合地基排水固结解析解

现有复合地基的竖向增强体往往无法兼具排水能力与竖向刚度。基于该工程现状，提出一种桩身开孔、能够达到排水效果的新型预制管桩，并针对其开展地基固结分析。假设孔洞流体满足管流条件以及管桩内往孔压连续，并考虑褥垫层的协调作用，推导出排水桩等应变固结解析解。基于该解析解，首先对砂井、碎石桩、不排水桩以及排水桩在相同外径尺寸情况下的排水固结能力进行了对比，结果显示开孔排水桩具有最好的排水固结能力。接着分析了桩身模量、褥垫层模量以及井径比的影响。最后分析了桩身性质（桩身开孔和桩体弹性模量）的影响，计算结果表明，排水能力和模量是影响固结性能的两个主要因素，且排水能力最为重要。但在排水能力相同的情况下，桩身模量越大，则固结越快。

Analytical solutions to drained consolidation of porous pipe pile

Defects exist in vertical reinforcement, such as drainage capacity and large bearing capacity cannot be achieved at the same time. This study developed a new type of porous pipe pile with drainage function. It is assumed the tube flow for pore fluid, and the continuous pore pressure according to Poiseuille equation. Then, the analytical solution of strain consolidation is deduced. The drainage pile presents the best consolidation capacity compared to sand drain, gravel pile and undrained pile. The effect of pile modulus, mattress modulus and radius ratio on consolidation are also analyzed. Drainage capacity and modulus are two main factors that affect the consolidation performance. The drainage capacity is the most important. Within the same drainage capacity, greater the modulus of the pile produces faster consolidation process.