［摘要］针对锚拉桩设计中土压力计算模式存在的问题，提出了三维土拱效应模型这种新的计算方法，通过有限元方法，对该模型的正确性进行了验证。在此基础上，讨论了锚头间距、土体粘聚力、内摩擦角及弹性模量对三维土拱效应的影响。结果表明：随着锚头间距增大，土拱效应减小；土体粘聚力和内摩擦角增大，土拱效应增强，但增大到一定值后，荷载分担比例变化较小，且粘聚力值变化对土拱效应的影响比内摩擦角更显著；土体弹性模量增大，荷载分担比例也增大，最大可达到100%，此时结构体系可采用点锚，三维土拱效应存在于整个锚索自由段。为进一步验证模型的正确性，进行了室内模拟试验，试验结果表明，挡板后水平及竖向均存在土拱效应。
［关键词］锚拉桩;荷载分担比例;数值分析;三维土拱效应；模型试验
中图分类号：TU473文献标识码：A文章编号：1002-848X(2011)10-0097-05
Experimental research and numerical analysis of three-dimensional soil arching effect on anchor piles
Li Chengfang1,2, Xiong Qidong2, Kong Fanlin2(1 College of Civil Engineering, Chongqing University, Chongqing 400010, China; 2 Chongqing Institute of Building Research, Chongqing 400015, China)
Abstract:Three-dimensional soil arching effect model was proposed as a new method  to solve the existing problems about earth pressure computation methods on the anchor pile, and  its correctness was verified by  finite element analysis. On this basis, the effect of the anchor head spacing, soil cohesion, internal friction angle and elastic modulus on three-dimensional soil arching was discussed. The results show that: with the anchor head spacing increasing, soil arching effect decreases; with the soil cohesion and internal friction angle increasing, the soil arching effect increases, but to a certain value, the load sharing ratio changes little. In addition, soil cohesion value is more significant than internal friction angle value to exerting soil arching effect. With the elastic modulus increasing, the soil arching effect also increases, and load sharing ratio increases simultaneously, the largest value is up to 100%, slope retaining structure can use point anchor for this moment. Three-dimensional soil arching effect exists in the whole anchor free section. To further verify the correctness of the model,  simulation experiment was carried out. The results show that there is soil arching effect in the horizontal and vertial plane.
Keywords:anchor piles; load sharing ratio; numerical analysis; three-dimensional soil arching effect; model test
作者简介：李成芳，高级工程师，一级注册结构工程师，注册土木（岩土）工程师,Email：LCF9133@163.com。
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