（广州市建筑科学研究院有限公司， 广州 510440）

［摘要］对于现场自平衡试验无法测得极限承载力的试桩，基于自平衡试验的基桩实测位移数据，采用三维有限元-无限元组合方法来模拟自平衡加载过程，结合位移反分析理论对桩土之间的界面力学参数进行反演计算，再利用反演得到的参数优化值进行正演计算分析，从而得到试桩极限承载力和竖向上拔最大位移值。实践证明，这种计算分析方法是合理可靠的，它是桩基极限承载力的理论预测分析与工程实际相联系的有效平台，为类似桩基工程的设计施工技术决策提供了切实可行的理论分析方法。

［关键词］自平衡试验； 大直径人工挖孔桩； 桩-土界面； 力学参数； 反演分析；无限元； 接触面单元

中图分类号：TU473-1文献标识码：A文章编号：1002-848X(2016)16-0093-04

Study on experiment and numerical simulation inversion analysis of large diameter manual hole digging pile-soil interface mechanical parameters

Tang Mengxiong, Qi Yuliang, Liu Bingkai, Hu Hesong

(Guangzhou Institute of Building Science Co., Ltd., Guangzhou 510440, China)

Abstract:The ultimate bearing capacity of test piles cannot be measured by field self-balanced test. Based on the measured displacement data of self-balanced test piles, 3D finite element-infinite element coupling method was used to simulate the process of self-balanced load. Combined with the theory of displacement inversion analysis, inversion calculation was conducted on pile-soil interface mechanical parameters. The parameter optimization values obtained by inversion were used for forward calculation analysis to obtain the ultimate bearing capacity of the test piles and the maximum displacement value of the vertical uplift. Practice has proved that the calculation method is reasonable and reliable and it is an effective platform relating theoretical prediction analysis with engineering practice of pile ultimate bearing capacity. It provides a feasible theoretical analysis method for construction technology decision-making in similar pile foundation engineering designs.

Keywords:self-balanced test; large diameter manual hole digging pile; pile-soil interface; mechanical parameter; inversion analysis; infinite element; contact surface element

*广东省应用型科技研发重大专项资金项目(2015B020238014),2016年广州市珠江科技新星项目（201610010099）。

作者简介：唐孟雄，博士，教授级高级工程师，一级注册土木工程师（岩土），一级建造师，Email:tmx@gibs.com.cn。