【摘要】 由于预应力的影响,煤矿预应力锚杆的振动特性与非预应力锚杆截然不同,通过理论分析、数值模拟和现场实测,分析了预应力锚杆弹性波检测的激振及其振动特性.采用理论分析和数值模拟方法分析了预应力锚杆锚固体波速的影响因素,得出了锚固体波速计算公式;并分析了激振应力波在预应力锚固系统内的传播规律.预应力和锚固体黏结强度大小不仅影响反射波形态及峰值大小,而且影响锚固体内次生反射的产生.以一现场预应力锚杆为对象,实测了不同预紧力时的预应力锚杆动力响应信号,验证了理论分析和数值模拟结果的正确性.更多还原

【Abstract】 Because of the effect of prestress,the vibration characteristic of prestressed anchor in coal mine is completely different from that of the nonprestressed anchor.In this paper,we analyzed the exciting and vibration characteristics of the prestressed anchor during elastic wave testing by theoretical analysis,numerical simulation and field measurement.First,the influencing factors of wave velocity of anchorage body in prestressed anchor were analyzed by theoretical analysis and numerical simulation,and the calculation formula of the anchorage body wave velocity was obtained.Moreover,the propagation rule of exciting stress wave in the prestressed anchor system was analyzed.The results show that the prestress and bond strength of anchorage body not only affect the reflected waveform and peak value,but also affect the formation of secondary reflection in the anchorage body.Finally,the dynamic response signals of prestressed anchor in different prestress levels were measured,to further verify the results of theoretical analysis and numerical simulation.更多还原