控温轧制下中空锚杆体的力学性能研究

摘要

针对一般轧制工艺生产的中空锚杆,出现的锚杆性能参差不齐、质量差,易造成锚杆失效和巷道失稳等问题,采用控温轧制的方法,以材质为Q345的D25中空锚杆体为例,利用感应加热控温轧制技术,将3种不同温度下的锚杆力学性能试验数据进行对比.研究结果表明:750 ℃控温轧制时,D25锚杆的抗拉力为206~230 kN,屈服力为160~185 kN,延伸率为19.5%~23.07%;800 ℃控温轧制时,D25锚杆的抗拉力为194~213 kN,屈服力为144~166 kN,延伸率为21.8%~24.9%;860 ℃控温轧制时,D25锚杆的抗拉力为175~200 kN,屈服力为123~155 kN,延伸率为23%~25%.相比较,在800 ℃控温轧制时,D25中空锚杆综合性能优良;反之,当在750 ℃控温轧制时,出现延伸率部分不合格的现象;当在860 ℃控温轧制时,虽有较好的塑性,但会出现抗拉力低于技术要求.不过,3种温度下控温轧制时性能均比较稳定.在锚杆支护中,使用一定温度条件下的控温轧制工艺加工的中空锚杆,综合性能优良且稳定,质量更稳定,更能有效实现围岩稳定与控制.%Anchor bar that is produced by general rolling technique will have the problems such as unstable mechanical property and low quality,which is more easily to cause rock bolt failure and roadway unstable.Based on the above problems,the method of temperature control rolling was put forward.Taking Q345 material for the D25 hollow bolt for example,the authors compared the test data under three different temperature by using induction heating temperature control rolling technology.The results showed that:under the condition of temperature 750 ℃ control rolling,D25 bolt tensile resistance is 206~230 kN,the yield stress is 160~185 kN,elongation is about 19.5% ~23.07%;under the condition of temperature 800 ℃ control rolling,D25 bolt tensile resistance is 194~213 kN,the yield stress is 144~166 kN,elongation is about 21.8% to 24.9%;under the condition of temperature 860 ℃ control rolling,D25 bolt tensile resistance is 175~200 kN,the yield stress is 123~155 kN,elongation is about 23 to 25%.In contrast,when the temperature is 800 ℃ control rolling,D25 hollow bolt comprehensive performance is good.On the contrary,when the temperature is under he condition of 750 ℃ control rolling,there is the elongation rate of partial failure phenomenon.When the temperature is under he condition of 860 ℃ control rolling,although the better plasticity,there will be less than the tensile strength of technical requirements.However,the properties of three kinds of temperature controlled rolling are relatively stable.Therefore,in the supporting of soft rock roadway,the anchor bar that is produced by certain controlled temperature rolling has more stable quality,and better overall performance,it can achieve the stability of rock effectively.