锤击法与静压法施工预制桩单桩承载力差异分析

Analysis on the Difference of Prefabricated Single Pile Bearing Capacity between Construction by Hammer-driven and Static-pressure

摘要:

目前国内的各种规范在计算预制桩的承载力时都不考虑打桩方式的影响。但在实际施工中，已经有越来越多的例子表明同样条件下锤击法施工比静压法施工得到的桩基承载力要低。从沉桩机理、挤密作用、孔隙水压力及其消散对施工后强度恢复的影响、土体等方面对2种方法造成的预制桩单桩承载力差异的原因进行了分析。

Abstract:

According to all of the technical standards in China, bearing capacity of prefabricated pile is calculated without taking into account the piling methods. But more and more engineering cases showed that under the same condition, the bearing capacity of pile foundation would be lower by hammer-driven than by static-pressure. The paper analyzed the difference from the soil mass and the effect on strength recovery after construction according to pile-setting mechanism, extruding function, pore pressure and dissipation.