爆破施工对相邻隧洞力学特性影响  

Study on Impact of Blasting Excavation on Mechanical Properties of Adjacent Tunnel

作　　者：金生吉[1,2] 芮勇勤[1] 林晓华[1] 

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110819 [2]沈阳工业大学建筑工程学院,辽宁沈阳110870

出　　处：《沈阳建筑大学学报（自然科学版）》2012年第2期221-227,共7页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(10872134);辽宁省博士科研启动基金项目(20101076)

摘　　要：目的为了解决相邻隧洞爆破施工可能造成隧洞围岩失稳问题,对爆破施工中对相邻隧洞围岩的力学特性影响进行研究.方法以红沿河核电站取水隧洞为依托工程,采用大型有限元FLACIX3D软件,对隧洞爆破施工过程进行数值模拟,分析隧洞围岩爆破产生的应力、位移和振速变化及其规律.结果在邻近相邻隧洞一侧直墙的中和上部均会产生明显的拉应力集中现象,隧洞围岩最大拉应力值亦出现在该位置,其应力集中程度明显大于远离开挖隧洞一侧.爆破震动产生的位移在迎爆一侧要明显的大于背爆一侧,垂直方向上的位移要比水平位移小得多,且迎爆侧直墙上部的区域合位移峰值最大.爆破引起的振动速度在水平方向上比垂直方向上要大很多,在背爆一侧震动速度为最低.结论速度最大峰值发生在迎爆侧直墙的上部,此处是震动最危险区域.根据应力、位移和震动速度分析,迎爆侧直墙与拱线连接处是爆破施工中最危险的区域,在爆破施工中应进行重点监测.In order to solve the instability problems caused by the blasting of the adjacent tunnel surrounding rock, the impact of mechanical properties of the adjacent tunnel blasting during the construction process were studied. We take Hongyan River Nuclear Power Plant water tunnel as support projects, using the finite ele- ment software PLAXIS3D blasting for tunnel construction process simulation, and analyse stress, deformation, vibration velocity which are produced by the blasting of tunnel wall rock. The concentration phenomenon of tensile stress would be produced on the middle and upper part of the vertical wall directly adjacent to the tun- net wall ,the maximum tensile stress value of surrounding rock also appears in this position ,the stress con- centration was significantly greater than those which is away from the excavating tunnel. The displacement generated by blasting vibration on the side of towards blasting is to be significantly larger than the side of a- way from blasting, the vertical displacement is much smaller than the horizontal displacement, and the big- gest part is the peak value of co-displacements on the upper part of the vertical wall of towards blasting. The vibration velocity caused by blasting in the horizontal direction is much larger than vertical direction, the lowest rate of vibration lies in the dorsal side. Maximum peak rate took place in the upper side of the vertical wall which is the most dangerous place of vibration. According to the stress, displacement and vibration velocity analysis, the connections between the vertical wall of the side of towards blasting and the arch wire are the most dangerous position in the blasting that should be be focused on monitoring.

关 键 词：隧洞 爆破施工 围岩稳定 应力 位移 

分 类 号：TU761[建筑科学—建筑技术科学]