竖向荷载作用下挤扩支盘桩的试验研究及设计分析

结合实际工程，通过挤扩支盘桩的静载荷试验和桩身轴力测试试验，深入地分析了竖向荷载作用下挤扩支盘桩的荷载传递机理和变形特性，同时，给出了挤扩支盘桩的单桩承载力计算公式。结果表明，挤扩支盘桩在加荷后期支盘承担50 %以上荷载，且支盘阻力体现端承力的性质；挤扩支盘桩与普通直桩相比，单桩承载力可提高60 %～100 %。

Experimental investigation and design analysis of vertically loaded cast-in-situ pile with expanded branches and plates

Based on the results of static loading tests and measurement of axial forces, the load-transferring mechanism and deformation behavior of vertically loaded cast-in-situ piles with expanded branches and plates are investigated and discussed through a pratical project. Further,an equation is developted to calculate the vertical bearing capacity. The results illustrate that the expanded branches or plates support the vertical load in excess of 50 % in post-loading; and the resistance of expanded branches or plates behaves as end-bearing force. The bearing capacity of the new type of pile increases as great as about 60 %-100 % over the common pile with constant cross-section.