用球形孔扩张理论估算支盘桩扩孔挤压效应

Calculation of squeezed efficiency of squeezed branch pile based on the expanding theory of the spherical hole

将球形孔扩张理论应用到支盘桩扩孔时径向应力的计算,考虑到扩孔时的油压数据,求得某一孔压下的支盘力,据此估算单桩极限承载力。通过现场静载荷试验,对比和分析了支盘桩与直杆桩承载力的大小,结果表明在相同条件下,支盘桩的承载力比直杆桩提高了75%,这充分说明了支盘桩在承受大吨位荷载方面具有较大的优越性。

The expanding theory of the spherical hole is introduced to the calculation of radial stress as the squeezed branch pile is drilled. A branch force under some pressure of the hole is obtained based on the data of oil pressure, and then the ultimate bearing capacity of the pile is calculated. The bearing capacity of the squeezed branch pile and the straight pile is analyzed and contrasted by means of the insitu loading test,and it is found that the bearing capacity of the squeezed branch pile is 75% more than that of the straight pile under the same conditions,which shows that the squeezed branch pile has great superiority in bearing great load.