挤扩支盘桩的工程实践及承载性能探讨

Research on bearing property and engineering applicationof cast-in-place piles with branches and plates

通过试验和理论分析,以及对一些工程实例的比较,对挤扩支盘桩这一近年开发出来的新桩型的承载性能进行了研究,证明其性能价格比远远好于普通灌注桩,是一种技术经济效益十分显著的桩型。同时针对目前众多文献中挤扩支盘桩承载力的计算均参照普通灌注桩的计算方法,提出了一些值得探讨的问题;指出挤扩支盘时的挤密效应,多支盘时的应力重叠效应和架空效应,以及支盘的外形尺寸和施工质量等对支盘桩的端阻和侧阻的发挥均产生不同的影响,在设计计算时必须认真加以考虑。

This paper investigates the bearing capacity and engineering application of the cast-in-place pile with branches and plates through experiment and theoretical analysis. The statistic shows that its performance-cost ratio is much higher than that of the common cast-in-place pile. It is mentioned in the paper that the bearing capacity of the cast-in-place pile with branches and plates is also effected by the following factor: the compaction effect, the stress overlapping effect, the aerial effect, the shape of the branches and plates as well as the construction quality. It is unreasonable to simply adopt that of the cast-in-place pile in the code.