冲击压缩下石英玻璃柱的破坏实验研究和数值模拟  

Experimental and numerical investigations on failure of quartz glass rod under impact compression

作　　者：徐振 熊迅 李天密 吕文银 周风华[1] XU Zhen;XIONG Xun;LI Tian-mi;LüWen-yin;ZHOU Feng-hua(Key Laboratory of Impact and Engineering of Ministry of Education,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学教育部冲击与安全工程重点实验室,浙江宁波315211

出　　处：《宁波大学学报（理工版）》2018年第2期37-43,共7页Journal of Ningbo University：Natural Science and Engineering Edition

基　　金：国家自然科学基金(11272163;11390361)

摘　　要：本文开展了一维应力冲击压缩下玻璃圆柱的压缩破坏实验研究.利用高速气枪装置发射石英玻璃圆柱试件垂直撞击刚性壁(Taylor撞击),采用超高速摄像机拍摄试件的冲击压缩破坏现象.实验中观测到一个产生于碰撞边界,向圆柱内部传播的移动破碎阵面,即失效波.在冲击压缩区内失效波的传播速度介于2~4 mm·μs^(-1)之间,随着冲击压缩载荷的增大而增大,随传播距离的增加而减小.经过一定时间,在试件的对向自由端区域,产生一个拉伸应力主导的碎裂区;与玻璃柱试件两端严重的破碎区域相比,试件中部产生一个相对透明区,其破碎程度较低.采用应力波分析方法说明了试件内部不同破碎特征区域的形成机理;采用离散元方法对实验过程进行数值模拟,取得了与实验现象一致的结果.In this paper we investigate the compressive failure of quartz glass rods vertically impacted on a rigid wall at high velocity(Taylor impact).The glass rod projectile is launched using a high-pressure gas gun.An ultra-high speed video camera is used to record the failure process of the glass rod.The impact creates a compressive region in the rod.It is found that starting at the impact face,a failure zone is developed in the compressive region and expands toward the far end of the projectile.The moving front of this failure zone can be viewed as a kind of“failure wave”,which travels at the rate of 2~4 mm?μs-1.The speed of the failure front increases with the compressive pressure,and may decrease with the propagation depth.After the impacting process,a spallation failure zone is occasionally identified which expands in the region of near the far end of the projectile.This spallation zone is attributed to the interactions between the unloading stress wave reflected from the free end of the projectile,and the longitude unloading wave initiated at the failure zone.Compared with the compressive failure zone in the impact end region,and the spallation zone in the free end region,relatively less damage is observed in the middle region of the projectile.The experimental observations can be explained from the stress wave analysis.Numerical simulations using the discrete element method are conducted,which give the results consistent qualitatively to the experimental observations.

关 键 词：失效波 Taylor撞击 石英玻璃柱 破坏和破碎 数值模拟 

分 类 号：O346.1[理学—固体力学]