（中煤科工集团重庆设计研究院有限公司， 重庆 400042）

［摘要］结合某超深岩质基坑工程实例（基坑深度最大33.20m），通过原位大型岩体直剪试验、锚索锚固段应力分布试验及锚杆（索）现场拉拔试验，获得岩土体和锚杆（索）指标力学性能参数值，作为进一步指导基坑支护设计施工的重要依据。试验结果表明：锚索锚固段应变在起始端最大，随锚固段长度的增加迅速衰减，呈近双曲线型分布；锚索预应力损失在锁定后0～15d内偏大，后期趋于平稳；锚入稳定岩层的锚杆（索）整体蠕变率偏低。最后，通过数值模拟和现场监测进一步验证了支挡结构体系的有效性。

［关键词］复杂环境；超深岩质基坑；直剪试验；锚杆；锚索；应力分布；预应力损失

中图分类号：TU470文献标识码：A文章编号：1002-848X(2021)03-0132-06

Experimental study on super-deep rock foundation pit under complex environmental condition

HOU Junwei, TANG Qiuyuan, LIU Jiayi

(Chongqing Research Institute of China Coal Technology & Engineering Group Corporation, Chongqing 400042, China)

Abstract:Combined with an example of an super-deep rock foundation pit (the maximum depth of the foundation pit is 33.20m), the values of mechanical parameters were obtained through in-situ large-scale rock mass direct shear test, stress distribution test of anchoring section of anchor cable and anchor rod (cable) pull-out test, which were used as an important basis for further guiding the design and construction of foundation pit support. The test results show that the strain of the anchoring section of the anchor cable is the largest at the initial end, and it decays rapidly with the increase of the length of the anchoring section, presenting a nearly hyperbolic distribution; the prestress loss of the anchor cable is larger in 0～15 days after locking and tends to be stable in the later period; the overall creep rate of anchor rod (cable) anchored into stable rock formations is low. Finally, the effectiveness of the supporting structure system is further verified through numerical simulation and field monitoring.

Keywords:complex environment condition;super-deep rock foundation pit;direct shear test;anchor rod;anchor cable;stress distribution;prestress loss

作者简介：侯俊伟，硕士，高级工程师，注册土木工程师（岩土），Email：116338270@qq.com。