动静载下全长砂浆锚固玻璃钢锚杆受力及失效特征分析  

Stress and failure characteristics of full-length mortar anchored GFRP bolts under dynamic and static loads

作　　者：王文杰[1,2] 刘超 黄永祥[3] 余龙哲 WANG Wen-jie;LIU Chao;HUANG Yong-xiang;YU Long-zhe(School of Resource and Environmental Engineering,Wuhan University of Science and Technology,Wuhan,Hubei 430081,China;Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources,Wuhan University of Science and Technology,Wuhan,Hubei 430081,China;Jinchuan Group Co.,Ltd.,Jinchang,Gansu 737100,China)

机构地区：[1]武汉科技大学资源与环境工程学院,湖北武汉430081 [2]武汉科技大学冶金矿产资源高效利用与造块湖北省重点实验室,湖北武汉430081 [3]金川集团股份有限公司,甘肃金昌737100

出　　处：《岩土力学》2023年第12期3617-3628,共12页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51974206);湖北省安全生产专项资金科技项目(No.KJZX202007007)。

摘　　要：针对爆破动载作用下玻璃钢锚杆的损伤失效问题,利用FLAC3D软件建立全长砂浆锚固玻璃钢锚杆数值计算模型,研究了预紧力静载和爆破动载下锚杆杆体、杆体与砂浆界面、砂浆与围岩界面的受力及失效特征,同时分析了动载强度、围岩及砂浆强度对锚杆受力的影响规律,并与现有试验结果对比,验证了研究结果的可靠性。研究结果表明:全长砂浆锚固玻璃钢锚杆最大轴向应力随动载强度的增大呈线性增大而随围岩或砂浆强度的增大而减小,且轴向应力分布较金属锚杆更为集中;两个界面剪应力均是沿杆体轴向迅速增大至峰值后快速减小为0,之后黏结性能相对较弱的界面先发生脱黏破坏,脱黏位置剪应力下降至残余黏结强度,同时剪应力峰值向孔底转移;玻璃钢锚杆剪应力分布较金属锚杆更集中,峰值位置更加突出;动载强度越大,破坏界面的脱黏长度和剪应力分布范围越大,而未破坏界面的剪应力峰值位置也会向孔底转移;围岩强度越大或砂浆强度越小,剪切破坏越倾向于发生在杆体−砂浆界面,反之,则越倾向于发生在砂浆−围岩界面。In order to study failure problem of glass fiber reinforced plastics(GFRP)bolts under blasting dynamic load,this study establishes a numerical model of full-length mortar anchored GFRP bolt using FLAC3D software.The stress and failure characteristics of the bolt,bolt-mortar interface,and mortar-rock interface under pre-tension static load and blasting dynamic load are investigated,and the influences of dynamic load intensity,surrounding rock strength and mortar strength on bolt stress are analyzed.The reliability of the research results is verified in comparison with the existing experimental results.The results show that the maximum axial stress of GFRP bolt increases linearly with the increase of dynamic load intensity and decreases with the increase of surrounding rock or mortar strength,and the axial stress distribution of GFRP bolt is more concentrated than that of metal bolt.The shear stress of the two interfaces increases rapidly to the peak along the bolt,and then decreases to zero.After that,the interface with relatively weak bonding properties is debonded at first,and the shear stress at the debonding position decreases to the residual bond strength.Meanwhile,the peak shear stress shifts to the bottom of the hole.The shear stress distribution of GFRP bolt is more concentrated than that of metal bolt,and the peak position is more prominent.The greater the dynamic load intensity,the larger the debonding length and shear stress distribution of the failure interface,and the peak position of the shear stress of the undamaged interface will be transferred to the bottom of the hole.The greater the surrounding rock strength or the smaller the mortar strength,the more likely the shear failure occurs at the bolt-mortar interface;on the contrary,it is more likely to occur at the mortar-rock interface.

关 键 词：全长砂浆锚固 玻璃钢锚杆 爆破动载 界面剪应力 失效特征 

分 类 号：TD353[矿业工程—矿井建设]