通过数值模拟计算，对DX单桩的沉降和承载力特性进行了研究，分析了在相同的桩长、桩径等条件下直孔桩、两个承力盘DX桩和三个承力盘DX桩的性能差异。沉降方面，在桩顶荷载增加相同的情况下，两个承力盘DX桩对桩顶沉降的控制明显强于普通直孔桩的控制效果，三个承力盘DX桩则进一步优越于两个承力盘DX桩。承载力方面，两个承力盘DX单桩的抗压承载力大约为直孔桩的1.5倍，而三个承力盘DX桩又进一步优越，大约为两个承力盘DX桩的1.2倍。

Based on numerical simulation, bearing capacity and settlement control for DX piles are studied. The property differences of conventional straight piles, DX piles with 2 bells and DX piles with 3 bells are presented in condition of identical length, diameter, and bearing capacity. Under the same load, DX piles with 3 bells have smaller settlement than that of DX piles with 2 bells and straight piles. As to bearing capacity, DX piles with 2 bells are 1.5 times greater than that of the straight piles, while DX piles with 3 bells are 1.2 times greater than that of DX piles with 2 bells. The paper can provide theoretical references for the design of bearing capacity of DX piles during the engineering practice．

张德华（1972—），女，山西朔州市人，北京交通大学副教授，博士，主要从事隧道工程研究工作