摘要
猴子岩地下厂房洞室群规模巨大,其中主厂房、主变室、尾调室跨度分别达到29.2m、18.8 m和23.5 m,厂区挤压破碎带及裂隙密集带发育,实测地应力量级为21.53 MPa^36.43MPa,为高地应力区。笔者采用三维非线性有限元法,根据6个剖面的监测资料,进行了包含岩锚梁岩台的上部第2级开挖跟踪反馈,并对后续第3、4级开挖进行了预测分析。结果表明,猴子岩地下厂房在第2级开挖后洞周变位较大,岩锚梁处最大变位为38.05 mm,塑性区发育深度6.02 m,该计算结果与现场监测结果吻合。预测第3、4级开挖后,边墙处变位分别增至47.26 mm和71.65 mm,塑性区进一步加深达8.4 m,但各洞室间未连通。本次计算为后续施工提供了重要的参考依据,并认为现有条件下地下厂房围岩整体稳定性良好,加固处理措施有效。
The underground powerhouse of Houziyan hydro-power station is composed of large cavern system including main plant,transformer room and tailrace surge chamber,with their spans being 29.2 m,18.8 m and 23.5 m respectively. The surrounding rock consists of compressive crushed zone and fissure zone,with measured geo-stress level up to 21.53 ~ 36.43 MPa,so this location is a high stress area. According to the monitoring data of 6 monitoring sections,2ndexcavation's tracking feedback and 3rd,4thexcavation's forecast analysis are carried out by using 3D nonlinear finite element method. The results show that after 2ndexcavation,the maximum deformation of rock bolt crane girder is 38.05 mm,its plastic zone depth is 6.02 m,and the computed results are in agreement with the site detection results. It is estimated that after 3rdand 4thexcavation,the deformation of side wall would increase up to47.26 mm and 71. 65 mm respectively,and its plastic zone would reach 8. 4m,but there is no link among the caves. The computed results provide important reference for subsequent construction,providing side evidence that surrounding rock of the underground powerhouse's overall stability is good,and reinforcing measures are effective.
出处
《地下空间与工程学报》
CSCD
北大核心
2016年第3期738-746,共9页
Chinese Journal of Underground Space and Engineering
关键词
地下厂房
监测
反馈
预测分析
Houziyan underground powerhouse
monitoring
feedback
predictive analysis