节理岩体隧道稳定性影响因素正交试验及锚杆作用要点研究  

Study on Orthogonal Test of Influencing Factors of Tunnel in Joined Rock Mass and Mechanical Effect of Bolt Support

作　　者：张志强[1] 何本国[1] 李永珑[1] 张光锦[1] 林永鹏[1] 

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,成都610031

出　　处：《武汉理工大学学报》2013年第2期90-96,共7页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(51278427);国家自然科学基金高铁联合基金(U1134208);新世纪优秀人才支持计划(NCET-10-0667);铁道部科技研究开发重大项目(2009G020-B-1);中央高校基本科研业务费专项资金(SWJTU11ZT33);教育部创新团队发展计划资助(IRT0955)

摘　　要：采用正交试验法研究裂隙岩体节理、岩块力学参数对隧道稳定性影响,提出了锚杆支护在不同裂隙岩体隧道中施作要点和内涵。结果表明:相对于塌方区、张开区,剪切滑移区更能反映节理面间剪切错动,可作为节理岩体隧道失稳的一个判断标准。层状岩体隧道稳定性主要影响因素是节理面"法向刚度和剪切刚度",而碎裂状岩体控制剪切滑移区主要因素是"节理面内摩擦角和粘聚力"。对于层状岩体,锚固效果受制于锚杆在节理面法向和切向刚度;对于碎裂状岩体,应强调注浆性质的锚固效果来提高其节理摩擦角和粘聚力,锚杆支护在提高"刚度"的同时,更应着重于提高岩体抗剪切能力,以有效提高碎裂岩体隧道稳定性。Orthogonal test was carried out to determine the effect of the joints of fractured rock and the mechanics pa rameters of rock mass for the tunnel stability. The key points and connotation of bolt for jointed rock mass were proposed by means of discrete element method. The research suggests that shear zone is the main reason for inducing progressive damage of rock,with respect to failure shape and open zone. So shear zone is proposed as criterion for stability of tunnel in jointed rock mass. The shear slip deformation in joint for tunnel constructed within layered rock mass is controlled by the deformation of joints. The major factors are the normal stiffness and the shear stiffness. In order to strengthen the stability of layered rock tunnel, you can increase the bolt shear and axial force to increase the joints shear and normal stiffness, re- duce the shear slip between the joint surface. The friction of joints and cohesion were the key to the shear slip deformation of fractured rock mass. So it is important to emphasized the anchoring effect of the grouting to improve the friction angle of joints and the cohesion. For fragmentation-like rock tunnels, setting the anchor need to consider the full guarantee of the grouting effect, not only can improve ＂stiffness＂ , but also improve rock shear resistance, even it is recommended that the application of hollow grouting anchor can effectively improve the fragmentation-like rock tunnel stability.

关 键 词：节理岩体稳定性 正交试验 离散元法 剪切刚度 锚杆支护 

分 类 号：TU453[建筑科学—岩土工程]