均质砂岩损伤临界值的研究及SHPB试验验证

发布时间：2018-02-27 03:40

  本文关键词： 元胞模型 SHPB试验 砂岩 损伤临界值　出处：《北京理工大学学报》2017年08期 　论文类型：期刊论文

【摘要】：砂岩在冲击荷载下,损伤量D通常在小于1的情况下就发生破坏,存在损伤临界值.本文首先根据分形几何理论和砂岩结构特征,建立2×3的元胞模型,理论解析出砂岩的不稳定损伤临界值为0.4,阶段变化的损伤临界值为0.119.然后通过直径50mm的SHPB试验结果分析,表明在砂岩动态损伤演化过程中有两个临界点,第1点为从线形损伤阶段到加快损伤阶段的临界点,对应的损伤量约为0.1;第2点为从损伤阶段到破坏阶段的临界点,对应的损伤量约为0.4,与理论研究十分吻合.该研究揭示了砂岩在损伤演化过程中发生破坏的临界问题.
[Abstract]:Under impact load, the damage amount D usually occurs when the damage is less than 1, and the damage critical value exists. In this paper, a 2 脳 3 cellular model is established based on fractal geometry theory and sandstone structural characteristics. Theoretical analysis shows that the critical value of unstable damage of sandstone is 0.4, and the critical value of damage of stage variation is 0.119.Then, through the analysis of SHPB test results of 50 mm diameter, it is shown that there are two critical points in the process of dynamic damage evolution of sandstone. The first point is the critical point from the linear injury stage to the accelerated damage stage, the corresponding damage amount is about 0.1; the second point is the critical point from the damage stage to the damage stage. The corresponding damage amount is about 0.4, which is in good agreement with the theoretical study, which reveals the critical problem of sandstone failure in the process of damage evolution.
【作者单位】： 中国矿业大学(北京)力学与建筑工程学院;金诚信矿业管理股份有限公司;
【基金】：国家自然科学基金资助项目(51574247,10272109) 国家教育部高等学校博士学科点专项科研基金资助课题(20060290009) 中央高校基本科研业务专项资金资助项目(2010QL05)
【分类号】：O346.5
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本文编号：1540996