摘要
隧道开挖结束后施加锚杆并在孔口喷薄层混凝土是常用的支护方式,而锚固区围岩性质在支护后将发生很大变化。本文针对考虑流变岩体中隧道逐步开挖与任意时刻施加支护问题,用圆柱型正交各向异性等效锚固体模拟锚固区,并建立材料特性变化后锚固区应力与位移的计算方法。对受双向等地应力作用的深埋圆形隧道,推导了可模拟为Boltzmann粘弹性模型的岩体在开挖与支护过程中原岩区与锚固区的位移与应力的解析解答,并分析了不同位置的力学状态及和各向异性程度对原岩区和锚固区的力学状态的影响,给出了若干结论。
The rockbolt support combined with shotcrete is widely used in tunnel construction. Owing to the reinforcement of rockbolt,the mechanical characteristics of supporting region will change a lot after supporting. In this paper,sequential excavation in rheological rock and installation delay of rockbolt support are accounted for,and homogeneous and cylindrically anisotropic inner zone around the tunnel is considered to simulate the supporting region. In addition,the method for the calculation of stresses and displacement in supporting region with mechanical characteristic changed after supporting is also established. For deeply buried tunnel subjected to hydrostatic initial stresses,the analytical solutions accounting for the whole process of circular tunnel construction are derived for the type of the rock simulated with Boltzmann viscoelastic model. The displacements and stresses in different positions are analyzed,and the influence of anisotropic degree of supporting region is illustrated for the mechanical responds of rock mass and supporting region. Some useful conclusions are provided at last.
出处
《地下空间与工程学报》
CSCD
北大核心
2013年第S1期1536-1542,1612,共8页
Chinese Journal of Underground Space and Engineering
基金
国家重点基础研究发展计划(973计划)项目(2014CB046901)
上海市自然科学基金项目(11ZR1438700)
国家杰出青年基金项目(51025932)
中央高校基本科研业务费专项基金
关键词
流变
锚喷支护
解析解
rheological
rockbolt support
analytical solution
