对挤扩支盘桩破坏性状的探讨

大量的静载试验和已建工程的经验证明 :挤扩支盘桩具有高承载力 ,明显不同于普通的钻孔灌注桩 ,特别是在承载力可调性方面 ,挤扩支盘桩具有很大的优越性。文章基于静载试验结果 ,研究和探讨了支盘桩的受力特性和破坏性状。研究结果表明 ,挤扩支盘桩在承力方面 ,支盘受力最大 ,约占总荷载的 6 0 %以上 ,沉降量明显低于同等条件下的钻孔灌注桩 ,且端阻力和侧阻力同时发挥。在破坏性状上 ,无论是荷载—沉降曲线还是动测检测结果 ,均说明了支盘下土体的局部剪切破坏是其破坏原因之一。

On the failure behavior of squeezed branch pile

The high bearing capacity of squeezed branch piles shows that such piles are different from conventional cast in place piles according to a lot of static load tests and experiences of projects finished. The bearing force character, failure behavior and loading transfer law of squeezed branch pile are studied in this paper based on static load test results. It is found that the bearing force of the branch is the largest in the bearing forces of the squeezed branch pile, about 60% of the total load, and the settlement of the pile is apparently lower than that of the cast in place pile on the same condition, and its end bearing force and skin friction force are developed at the same time. The soil failure beneath the branch or the disk is the main cause of the shear failure of the pile based on the analysis of the curve of load settlement and the dynamic pile test results.