脆性材料裂纹与损伤相互作用的试验研究

发布时间：2018-03-06 22:07

本文选题：岩石力学　切入点：脆性材料　出处：《岩石力学与工程学报》2017年11期 　论文类型：期刊论文

【摘要】：为研究岩石等脆性材料的损伤对裂纹动态扩展的影响,采用动态透射焦散线方法,模拟脆性材料裂纹与损伤相互作用的动态过程,进行多种损伤情况下有机玻璃试样裂纹动态扩展过程试验研究,讨论不同类型损伤对脆性材料裂纹动态扩展规律的影响和裂纹与损伤相互作用的机制。试验结果表明:不同类型的损伤对裂纹扩展影响不同,除裂纹型损伤外,其他几种类型损伤的存在均会引起裂纹扩展出现短暂停滞,停滞时间与损伤的尺寸及距离扩展裂纹路径的距离有关系;裂纹扩展路径上存在单个圆孔时会影响裂纹扩展速度,裂纹消耗能量增大;而多个圆孔情况下,材料局部弱化,裂纹扩展速度增大,而裂纹扩展消耗能量降低;表面损伤和局部贯通裂纹的尺寸、相对裂纹扩展路径距离等影响裂纹扩展速度,但能量消耗并未增大;对称裂纹相互竞争,同步扩展,裂纹尖端位置或裂纹长度的微小差别(例如裂纹长度相差3.68%)就会对裂纹起裂产生明显影响,导致2个裂纹起裂时间不同,裂纹扩展以后,先起裂的裂纹尖端应力强度因子大说明能量集中到相应裂纹尖端,从而越有利于该裂纹的扩展,扩展速度也就越大(相差约38.9%),相同条件下裂纹扩展所消耗的能量也越大。
[Abstract]:In order to study the effect of damage on crack dynamic propagation in rock such as brittle materials, the dynamic process of crack and damage interaction in brittle materials is simulated by using dynamic transmission caustic line method. The dynamic crack propagation process of organic glass specimen under various damage conditions was studied. The effects of different types of damage on crack dynamic propagation and the interaction between crack and damage in brittle materials are discussed. The experimental results show that different types of damage have different effects on crack propagation, except for crack type damage. The existence of several other types of damage can cause the temporary stagnation of crack growth, and the stagnation time is related to the size of the damage and the distance from the propagating crack path, and the existence of a single circular hole in the crack growth path will affect the crack growth speed. The energy consumption of the crack is increased, and the local weakening of the material, the increase of the crack growth speed, and the decrease of the energy consumption of the crack growth, the surface damage and the size of the local through crack are obtained under the condition of multiple circular holes. Relative crack propagation path distance affects crack growth speed, but energy consumption does not increase. Symmetric cracks compete with each other and grow synchronously. The tiny difference of crack tip position or crack length (for example, the difference of crack length 3.68) will have a significant effect on crack initiation, resulting in two crack initiation time is different, after crack propagation, The large stress intensity factor at the crack tip shows that the energy is concentrated at the crack tip, so the more favorable the crack propagation is, the larger the propagation speed is (about 38.9%), and the larger the energy consumption of crack propagation is under the same conditions.
【作者单位】：中国地震局地壳应力研究所;北京大学工学院力学与工程科学系;
【基金】：国家自然科学基金资助项目(41704096) 中央级科研院所基本科研业务专项资助项目(ZDJ2017 13)~~
【分类号】：TU45

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