动静荷载下巷道围岩倾斜裂纹的动焦散试验

发布时间：2018-04-03 15:27

  本文选题：动静荷载　切入点：裂纹倾角　出处：《采矿与安全工程学报》2016年04期

【摘要】：利用爆炸加载动态焦散线测试系统,采用PMMA材料加工模型试件,进行裂纹扩展规律的动焦散试验研究。结果表明:预制裂纹b端在应力波作用下起裂,扩展轨迹出现翘曲变化的现象,大体上沿水平方向扩展;裂纹b端扩展位移随倾角θ呈现增大和减小交替变化的规律,在-45°~45°内,扩展位移曲线大体上关于直线θ=0°对称,在-75°~-45°和45°~75°内,位移曲线呈现较大差别;扩展位移曲线在θ=-45°,θ=0°和θ=60°处达到峰值,分别为22,31,36 mm,在θ=±30°处达到低谷值9 mm和11 mm;应力强度因子KⅠd变化曲线和能量释放率G变化曲线具有相似的变化规律,均先达到峰值,后反复振荡变化、多次出现峰值;KⅠd值和G值与能量紧密相关,当两者的数值相对较大时,相应裂纹扩展位移较大,反之,裂纹扩展位移较小。
[Abstract]:The dynamic caustic test of crack growth was carried out by means of explosive loading dynamic caustic line test system and PMMA material processing model specimen.The results show that the crack start crack at the b end under the action of stress wave, and the propagation trajectory is warped, and the propagation displacement of the b end of the crack increases and decreases alternately with the dip angle 胃, and in the range of -45 掳~ 45 掳, the propagating displacement of the b end of the crack increases and decreases alternately with the dip angle 胃.The extended displacement curve is about the symmetry of the straight line 胃 0 掳, and the displacement curve is quite different in the range of -75 掳-45 掳and 45 掳~ 75 掳, the extended displacement curve reaches the peak value at 胃 -45 掳, 胃 -0 掳and 胃 ~ (60) 掳, and the extended displacement curve reaches the peak value at 胃 -45 掳, 胃 ~ (0 掳) and 胃 ~ (60 掳).At 胃 = 卤30 掳, the lowest values are 9 mm and 11 mm, respectively, and the curve of stress intensity factor K 鈪，

本文编号：1705789