爆生气体对邻近硐室背爆侧预制裂纹影响机理

发布时间：2018-07-05 06:42

本文选题：爆生气体 + 邻近硐室　；参考：《煤炭学报》2016年01期

【摘要】：采用动态焦散线实验方法,研究爆炸荷载作用下邻近硐室背爆侧裂纹扩展规律时发现,伴随爆生气体释放出现的弧线型应力集中区是爆生气体引起的主应力差峰值位置,与背爆侧裂纹的扩展有较大的关联。实验研究表明:炸药爆炸后,产生的应力波首先作用于硐室背爆侧裂纹,随后爆生气体产生的准静态应力作用于裂纹,对裂纹的扩展起主要作用,而卸载波主要作用于裂纹扩展后期,使裂纹出现翘曲现象。当弧线型应力集中区接近扩展中的裂纹时,裂纹扩展速度达到峰值,约等于弧线型应力集中区的移动速度,之后,裂纹尖端与弧线型应力集中区的相对距离基本不变,当该应力集中区越过裂纹尖端,裂纹扩展速度逐渐减小,最终止裂。裂纹尖端动态应力强度因子与裂纹扩展速度具有相似的变化规律,峰值动态应力强度因子出现在弧线型应力集中区越过裂纹尖端之前。基于该发现进行的研究证实了爆生气体对邻近巷道裂纹扩展的主导作用,深化了爆炸荷载对邻近巷道影响机理的研究。
[Abstract]:By using the dynamic caustic line method, the experimental results show that the arc stress concentration zone accompanied by the explosion gas release is the peak position of the principal stress difference caused by the explosion gas. It is closely related to the propagation of the crack on the back side. The experimental results show that the stress wave produced after explosive explosion acts on the crack at the back of the chamber first, and then the quasi-static stress produced by the explosion gas acts on the crack, which plays a major role in the crack propagation. The unloading wave acts mainly on the later stage of crack growth, which makes the crack warp. When the curve stress concentration region is close to the propagating crack, the crack growth velocity reaches the peak value, which is about equal to the moving speed of the arc stress concentration region. After that, the relative distance between the crack tip and the arc stress concentration region is basically unchanged. When the stress concentration zone crosses the crack tip, the crack growth velocity decreases gradually, and finally the crack stops. The dynamic stress intensity factor at the crack tip is similar to the crack growth velocity, and the peak dynamic stress intensity factor appears before the curve stress concentration zone passes the crack tip. The research based on the discovery confirms the dominant effect of explosion gas on the crack propagation of adjacent roadways and deepens the study of the influence mechanism of explosion load on adjacent roadways.
【作者单位】：中国矿业大学(北京)力学与建筑工程学院;深部岩土力学与地下工程国家重点实验室;
【基金】：国家自然科学基金资助项目(51274204;51134025) 教育部新世纪优秀人才支持计划资助项目(NCET-12-0965)
【分类号】：TD235.1

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