爆破动载作用下新喷射混凝土累积损伤效应的模型实验

发布时间：2018-05-24 06:26

本文选题：爆炸力学 + 累积损伤　；参考：《爆炸与冲击》2016年03期

【摘要】：利用模型实验的手段模拟了巷道的爆破掘进,并在实验中辅以声波测试,通过分析声波波速和声波波形的变化规律,研究了新喷射混凝土在多次爆破动载作用下的累积损伤效应。实验结果表明,爆破次数、与掌子面之间的距离和爆破药量均会影响喷射混凝土的累积损伤,这种影响体现在声波波速和波形2个方面:爆破次数增加、距离减小和药量增加,则声速降低值越大,波形变化越明显,即累积损伤值越大;爆破次数和距掌子面的距离均与累积损伤呈非线性关系,其中距离与爆破损伤之间的非线性关系可以用二次多项式进行较好的拟合;第一次爆破对声速和波形影响最大,造成的单次损伤值也最大;在小药量爆破的情况下,测试面的最大累积损伤值达到了0.126 8,表明爆破近区喷射混凝土的损伤是需要关注的重点。
[Abstract]:The blasting tunneling of roadway is simulated by the method of model experiment, and the acoustic wave test is used to analyze the variation law of acoustic wave velocity and wave. The cumulative damage effect of new shotcrete under multiple blasting dynamic loads is studied. The experimental results show that the cumulative damage of shotcrete will be affected by blasting times, distance to palm surface and explosive quantity, which is reflected in two aspects of acoustic wave velocity and waveform: the increase of blasting times, the decrease of distance and the increase of explosive quantity. The larger the decrease value of sound velocity, the more obvious the waveform change, that is, the bigger the cumulative damage value, the nonlinear relationship between the blasting frequency and the distance from the palm surface and the cumulative damage. The nonlinear relation between distance and blasting damage can be fitted well by quadratic polynomial. The first blasting has the greatest influence on the sound velocity and waveform, and the single damage value is the largest. The maximum cumulative damage value of the test surface is 0.126, which indicates that the damage of shotcrete near the blasting area should be paid more attention to.
【作者单位】：中国矿业大学(北京)力学与建筑工程学院;
【基金】：教育部高等学校博士学科点专项科研基金项目(20120023110009)
【分类号】：O38

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