Failure mechanism and safety control technology of a composite strata roadway in deep and soft rock masses:a case study  

作　　者：ZHAO Chengwei ZHOU Hui SUN Xiaoming ZHANG Yong MIAO Chengyu WANG Jian 

机构地区：[1]State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory for GeoMechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China [4]School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China

出　　处：《Journal of Mountain Science》2024年第7期2427-2444,共18页山地科学学报（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant No.51874311,52174096)。

摘　　要：The construction of coal mines often encounters deep composite soft rock roadways,which is characterized by significant deformation and poor stability.To deeply study the failure mechanism and large deformation challenges of a composite strata roadway in deep and soft rock masses,a numerical model of 3DEC tetrahedral blocks was established based on the method of rock quality designation(RQD).The results showed that original support cannot prevent asymmetric failure and large deformation due to the adverse geological environment and unsuitable support design.According to the failure characteristics,a coupling support of“NPR bolt/cable+mesh+shotcrete+steel pipe”was proposed to control the stability of the surrounding rock.The excellent mechanical properties of large deformation(approximately 400 mm)and high constant resistance force(bolt with 180 k N;cable with 350 k N)were evaluated by the tensile tests.The numerical results showed that the maximum deformation was minimized to 243 mm,and the bearing capacity of the surrounding rock of the roadway was enhanced.The field test results showed that the maximum deformation of the surrounding rock was 210 mm,and the forces of the NPR bolt and cable were stable at approximately 180 k N and 350 k N,respectively.This demonstrated the effectiveness of the coupling support with the NPR bolt and cable,which could be a guiding significance for the safety control of large deformation and failure in deep composite soft rock roadways.

关 键 词：3DEC Composite strata roadway Soft rock NPR bolt and cable Asymmetric large deformation 

分 类 号：TD353[矿业工程—矿井建设]