改进型后张法大管桩抗弯试验研究

采用四点弯曲试验方法，对6根改进型后张法大管桩进行抗弯试验，测得桩身开裂弯矩和极限弯矩，并与国内同类型高性能管桩的抗弯性能进行对比分析。结果表明：改进型后张法大管桩的抗裂性能有很大的提高，而极限抗弯承载 力提高不明显，在小范围内提高混凝土有效预压应力能提高管桩的抗裂性能；同时，悬臂端的长度对抗弯试验有很大的影响，悬臂端的最佳长度为0.08L~0.1L。

Experimental study on bending test of new large-diameter post-tensioned prestressed concrete cylinder pile

Bending tests of six large-diameter post-tensioned prestressed concrete piles are carried out by the four-point bending method, and the cracking capacity and ultimate bearing capacity are obtained. The results of bending tests are compared with those for other piles widely used in China. The results show that the flexural performance of large-diameter post-tensioned prestressed concrete pile is better than that of other piles, so we can conclude that the ultimate flexural capacity of concrete piles can be improved by increasing the effective prestress within a small range. We also find that the length of cantilever is important in bending test, and the recommendable length of cantilever is between 0.08L and 0.1L.