动态爆生裂纹相互影响的试验研究

发布时间：2018-01-17 21:18

  本文关键词：动态爆生裂纹相互影响的试验研究　出处：《爆破》2016年02期 　论文类型：期刊论文

  更多相关文章： 爆生裂纹 动态应力强度因子 拉伸破坏 剪切破坏 应力波

【摘要】：采用以有机玻璃(PMMA)为材料的模型试验方法,分析了试件的破坏形态和裂纹尖端的应力特征,研究了对向切槽炮孔的不同竖向间距对爆生裂纹扩展的影响。结果表明:爆生裂纹扩展过程中,裂纹速度震荡减小,裂纹尖端应力变化经历两个阶段,Ⅰ阶段(0~110μs)裂纹尖端动态应力强度因子迅速减小,试件破坏以拉伸破坏为主;Ⅱ阶段(110μs~止裂)裂纹尖端动态应力强度因子先增大后减小,试件破坏兼有拉伸破坏和剪切破坏。炮孔的竖向间距的不同对爆生裂纹Ⅰ阶段扩展影响不大,对Ⅱ阶段扩展影响显著。对向裂纹起到自由面作用并引导己方裂纹向其发生偏转,从对向裂纹面处反射的应力波加强了己方裂纹尖端的应力集中。
[Abstract]:The fracture morphology and stress characteristics at crack tip of the specimens were analyzed by using PMMA as the material. The effect of different vertical spacing on crack propagation is studied. The results show that the crack velocity oscillation decreases and the stress change at crack tip goes through two stages. In the first stage, the dynamic stress intensity factor at the crack tip decreases rapidly, and tensile failure is the main failure of the specimen. In the second stage, the dynamic stress intensity factor at the crack tip increases first and then decreases. Both tensile and shear failure occur in specimen failure, and the vertical spacing between the holes has little effect on the stage 鈪，

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