材料复合桩的现场承载性能试验研究

基于水平荷载作用下桩基的弯矩沿深度呈由上向下骤减的规律，将桩的上部设计为抗弯性能良好的钢管桩而下部为抗弯性能较弱的PHC桩，并选择适当的部位通过焊接等方式连接两种桩型。在现场进行锤击试验、水平承载力试验和连接部位抗弯性能试验，将复合桩的压应力、拉应力和水平承载力与材料允许值对比比较。结果表明，所选择的材料复合型桩充分发挥了材料性能，尤其在水平承载力方面表现突出，且不同材料桩型连接部位性能良好。试验结果为桩基的改进提供了新思路和试验依据。

Experimental study of field bearing capacity of material composite piles

Based on the rule that the moment of piles under horizontal load decreases suddenly along the depth, the top of pile was designed as steel pipe piles having good bending properties and the rest of it was designed as PHC pile having weak bending properties, and chosen desired location to connect by welding and so on. Hammering test, horizontal bearing capacity test and bending properties test were carried out; and then compare compressive stress, tensile stress and horizontal bearing capacity with allowable value. Test results show that material composite pile gives full play to material properties, especially performing well at the aspect of horizontal bearing capacity; and the connection has a good performance. The study results can provide new ideas and test basis for the improvement of piles.