强岩爆隧道分区爆破卸压数值模拟  

Numerical Simulation of Zonal Destress Blasting in Strong Rock Burst Tunnel

作　　者：康永全 孟海利 郭云龙 孙崔源 薛里 孙鹏昌 KANG Yongquan;MENG Haili;GUO Yunlong;SUN Cuiyuan;XUE Li;SUN Pengchang(Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《铁道建筑》2022年第12期149-152,共4页Railway Engineering

摘　　要：基于深部岩体分区破裂化理论和高围压爆破破碎机理,提出在隧道斜前方第四条或第五条破裂带分区爆破卸压的方法。建立三维精细化数值计算模型,分析爆破卸压前后围岩应力场和变形、锚杆轴力、二次衬砌结构变形和压应力变化情况。结果表明:爆破卸压后隧道轮廓面处Barton岩爆判别系数从0.50~0.90降至0.15~0.30,岩爆发生的概率及烈度降低;卸压后围岩变形增大,锚杆受力增加,地应力得到有效释放并传递给初期支护结构,降低了二次衬砌结构的受力,二次衬砌压应力降低了23.6%。爆破卸压通过有效释放应变能和转移高应力的方式达到防治岩爆的效果。Based on the theory of zonal fracturing of deep rock mass and the fragmentation mechanism of high confining pressure blasting,a method of zonal destress blasting in the fourth or fifth fracture zone in the oblique front of the tunnel was proposed.A three-dimensional refined numerical calculation model was established to analyze the change of the stress field and deformation of surrounding rock,the axial force of anchor bolt,the deformation and compressive stress of secondary lining structure before and after destress blasting.The results show that the Barton rock burst discrimination coefficient at the tunnel contour decreases from 0.50~0.90 to 0.15~0.30 after destress blasting,and the probability and intensity of rock burst decrease.After destress blasting,the deformation of surrounding rock increases,the stress of anchor bolt increases,the ground stress is effectively released and transferred to the primary support structure,reducing the stress of the secondary lining structure,and the pressure stress of the secondary lining decreases by 23.6%.The destress blasting can prevent rock burst by effectively releasing strain energy and transferring high stress.

关 键 词：交通隧道 分区卸压爆破 数值模拟 高应力 应力转移 岩爆判据 

分 类 号：U455.41[建筑科学—桥梁与隧道工程]