摘要
在分析煤矿巷道锚杆支护构件破坏形式与原因的基础上,研究了锚杆各构件,包括杆体、螺纹段、托板、球形垫圈及减摩垫圈的力学性能。采用理论计算与数值模拟分析了杆体与螺纹段在不同受力状态下的应力分布特征。在实验室进行了锚杆形状、参数对其锚固力及安装阻力影响的试验,托板压缩性能及锚杆尾部构件匹配性试验。研究了树脂锚固剂的力学性能及影响因素。研究结果表明:锚杆受拉伸、弯曲、扭转、剪切及其组合作用,煤矿巷道锚杆处于屈服是一种常态,杆体有4个位置易发生破断。螺纹显著改变了螺纹段表面及附近部位的应力分布,在螺纹牙底处出现明显的应力集中。拱形托板压缩变形可分为5个阶段,拱高必须达到一定值才能保证足够的承载能力。锚杆尾部构件几何形状、参数及力学性能应相互匹配,才能使锚杆处于较好的受力状态。树脂锚固剂应与杆体、钻孔匹配,保证锚杆-锚固剂、锚固剂-围岩之间界面有良好的黏结性能。研究成果已应用于多类困难巷道,大幅减少了锚杆支护构件的破坏,显著提高了巷道支护效果。
Based on the analysis on damage modes of rock bolting components and factors resulting in the failure,their mechanical performances,including rebar,thread,plate,domed washer and anti-friction washer,were studied.The stress distribution features of rebar and thread on varying loading states were analyzed through theoretical calculation and numerical simulation. The effects of rebar profile and geometric parameters on the anchorage force and installation resistance were tested in laboratory,the compressive performance of plates and the compatibility between the components on bolt end were also tested. The mechanical performances of resin capsules and their affecting factors were studied. Research results point out: bolt rods are acted by tension,bending,torsion,shear and their combination,bolt yielding is in normal state,and generally fracture at four points in coal mine roadways. Thread teeth sharply change the stress distribution on its surface and adjacent zone,and stress concentration occurs in the valley of thread teeth. The compressive deformation of domed plates can be divided into five stages,and the arch height of plates should be more than a fixed value to guarantee their bearing capacity. The profiles,parameters and mechanical performances of the components on bolt end should be compatible to guarantee rock bolts laying in good stressstate. Resin capsules should be compatible with the rebar and borehole to guarantee a better cohesive performance between the interfaces of bolt-resin and resin-rock. The research achievements have been applied in many complicated roadways,the fractures of bolting components have been greatly reduced,and bolting performances obviously improved.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2015年第1期11-23,共13页
Journal of China Coal Society
基金
国家自然科学基金重点资助项目(U1261211)
国家"十二五"科技支撑计划资助项目(2012BAK04B06)
关键词
锚杆
构件
力学性能
匹配性
煤矿巷道
rock bolts
components
mechanical performances
compatibility
coal mine roadways
