硬岩竖井爆破损伤区探测及衬砌荷载  

Detection on blasting damage zone of hard rock shaft and lining load

作　　者：蒲松[1] 张睿[2,3] 方勇[1] 余涛[1] 方晓峰[1] 田青峰 PU Song;ZHANG Rui;FANG Yong;YU Tao;FANG Xiaofeng;TIAN Qingfeng(Southwest Jiaotong University,Chengdu Sichuan 610031,China;Sichuan Chuanjiao Cross Road&Bridge Co.,Ltd.,Guanghan Sichuan 618300,China;Tianjin University,Tianjing 300352,China)

机构地区：[1]西南交通大学,四川成都610031 [2]四川川交路桥有限责任公司,四川广汉618300 [3]天津大学,天津300352

出　　处：《中国安全生产科学技术》2021年第10期85-91,共7页Journal of Safety Science and Technology

基　　金：国家自然科学基金项目(52078428)。

摘　　要：为研究硬岩竖井受爆破开挖扰动的影响,依托米仓山公路隧道竖井工程,采用RSM-RCT(B)测试系统探测竖井爆破损伤区范围为1.1~1.4 m,并利用残余地质强度指标标定损伤区力学参数,将其纳入收敛约束法和数值分析中,以评估损伤区对竖井围岩及衬砌荷载的影响。研究结果表明,在硬岩竖井中开挖爆破是造成岩体损伤区的关键因素,地应力方向和大小对硬岩损伤区分布基本无影响。分析结果表明,爆破损伤区导致围岩变形增大,从而使得衬砌荷载增加,最大剪应力出现在损伤区与未破坏岩体之间的交界处,大小为16 MPa,同时靠近该位置的衬砌荷载也会变大,较深竖井可采用分区段支护,降低投资成本。研究结果可为硬岩竖井开挖荷载计算及设计优化提供一定参考。In order to study the influence of blasting excavation disturbance on the hard rock shaft,relying on the shaft engineering of Micangshan highway tunnel,the RSM-RCT(B)test system was used to detect the blasting damage zone of shaft,and the result ranged from 1.1 m to 1.4 m.The residual geological strength index(GSI)was used to calibrate the mechanical parameters of the damage zone,and incorporated into the convergence constraint method and numerical analysis to evaluate the influence of the damage zone on the surrounding rock and lining load of shaft.The results showed that the key factor which caused the rock mass damage zone was the blasting excavation in the hard rock shaft,while the direction and magnitude of crustal stress had little influence on the distribution of hard rock damage zone.The blasting damage zone led to the increasing deformation of surrounding rock,thus the increasing lining load.The maximum shear stress was 16 MPa,which occurred at the junction between the damage zone and the undamaged rock mass.At the same time,the lining load near this position would also become larger.Consequently,the subsection support could be used for the deep shaft to reduce the investment cost.The study results provide some reference for the excavation load calculation and optimization design of hard rock shaft.

关 键 词：硬岩竖井 爆破损伤区 衬砌荷载 数值模拟 

分 类 号：X947[环境科学与工程—安全科学] U45[建筑科学—桥梁与隧道工程]