挤扩多盘桩的土体极限承载力研究

根据挤扩多盘桩盘下土体的滑移破坏形式，运用滑移线理论确定的盘下土体应力计算模式，结合塑性势理论和虚功原理，确定挤扩多盘桩的土体极限承载力，修正并完善了现有的桩端承载力及桩侧阻力的计算公式，提出了全新挤扩多盘桩单桩承载力的计算公式．

Ultimate bearing capacity of soil about push-extend multi-under-reamed concrete pour pile

Because of the setting up of Multi-under-reamed, the stress of soil change near the under-reamed is changed, It is unreasonable that the end resistance and side resistance is added simply in the present formula. The ultimate bearing capacity of the soil around the Push-extend Multi-under-reamed Pile is decided, according to the failure principle of soil and the theory of sliding line, at the same time, the calculate model of the soil stress is applied, to combine the theory of plasticity potential energy with the principle of imaginary. In this foundation, the up-to-date formula of ultimate bearing capacity of the single pile is put forward. The formula of calculating end resistance and side resistance is corrected and perfected.