中文摘要：

针对屈服强度500 MPa以上矿用锚杆杆体容易出现断裂失效的问题,采用化学成分分析、力学性能测试、扫描电镜及金相显微等综合试验手段对两种破断强力锚杆进行了分析,结合锚杆的实际受力特征及断裂失效分析学理论,从微细观机制初步揭示了杆体破断原因。结果显示材质及加工缺陷等内在属性是断裂的内因,工作环境、应力腐蚀及复杂受力状态是外因,锚杆的韧性则决定了断裂的类型和断口形态。并相应提出了减少杆体破断几率的综合方法,包括改善受力状态、全长锚固、优化外形、防腐蚀处理等。

英文摘要：

Comprehensive test methods of chemical composition analysis,mechanical properties test,SEM and metallographic microscopy were used to analyze the frequent fracture failure of rock bolts whose yield strength exceeded500 MPa.The reasons of fracture failure were preliminarily revealed from micro-mesoscopic mechanism angle combined with actual stress characteristics and theories of fracture failure analysis. The results showed that intrinsic attributes such as material and manufacturing deficiency were internal factor,while working environment,stress corrosion and complex stress state were external factor.The ductility of rock bolts determined the fracture mode and morphology.Comprehensive methods including improving stress state,full-length anchored,optimizing contour of rock bolts and anticorrosion processing were put forward to reduce the probability of fracture failure.