路堤荷载下带桩帽刚性桩复合地基桩土应力比分析

Analysis of Stress Ratio between Pile and Soil in Composite Foundation of Rigid and Capped Piles under Embankment Loads

路堤一般由填土、碎石等散体材料组成,刚性桩复合地基中,桩土刚度差异较大引起的桩土间沉降差异,会导致路堤内部出现相对竖向位移。通过路堤填土的受力平衡分析,根据桩土差异沉降,求解出桩帽和桩帽间土体的应力分配,并结合桩帽下应力分配得出桩身应力,最终求解出桩土应力比及桩的荷载分担比例。工程实例监测结果验证了文中计算公式的适用性和可靠性。通过分析计算结果和实测结果,得出了一些路堤荷载下刚性桩复合地基的承载规律,可供理论研究和工程设计参考。

Because an embankment is usually made up of granular materials such as filled soils and gravels, there are settlement differences in an embankment caused by differences in stiffness of piles and soils. The stress ratio between a pile cap and its surrounding soil is solved by analyzing the equilibrium condition of the embankment under loads. Then the stress in a pile shaft is worked out through further analysis of the stress distribution under the pile cap. The reliability of this method has been validated by field monitoring in an engineering project. Base on the results of calculation and field monitoring, the load bearing regularity of composite foundations of rigid piles is concluded to provide a reference for future theoretical studies and engineering designs.