摘要
本文以渝怀铁路增建二线新四方沱隧道为背景,利用有限差分强度折减研究了隧道无支护时围岩稳定性。基于数值计算结果提出了初期支护优化形式,取消了锚杆支护并应用于现场。结果表明,优化后的初期支护中喷射混凝土最大压应力为其极限抗压强度的44.5%,其抗压性能得到更充分的利用;钢架的压应力是钢材极限抗压强度的50%,钢架与喷射混凝土均有足够的安全余量。现场监测结果验证了该优化方案的安全性与可行性。该方案已在新建渝怀铁路新四方沱隧道中推广。
Based on new Sifangtuo tunnel of the newly-added railway line Yuhuai railway,strength storage of rock mass is calculated using the strength reduction method as the stability index of the rock mass.According to numerical results,optimization is proposed to cancel the rock bolts and use in the field practise.The results show that maximum compressive pressure is the 44.5%of the limit compressive strength in the primary support.The compressive performance was sufficiently employed.The compressive stress of the girders is the 50%of the limit compressive strength.The safety abundance of the girders and shotcrete is enough..Field test proves the safety and feasibility of the optimization plan.The optmized plan has been used in new Sifangtuo tunnel.
作者
赵治冶
ZHAO Zhi-ye(Lunan High Speed Railway Co.,Ltd.,Ji'nan 250101,China)
出处
《价值工程》
2019年第16期72-74,共3页
Value Engineering
关键词
初期支护
强度折减法
现场监测
优化设计
primary support
strength reduction method
site monitoring
optimization design
