Study of propagation behaviors of mode I cracks under blasting stress#br# wave based on RPC specimens
WAN Duanying1，2，ZHU Zheming1，2，LIU Ruifeng1，2，LIU Bang1，2，LI Jianfei1，2
(1. MOE Key Laboratory Deep Underground Science and Engineering，Sichuan University，Chengdu，Sichuan 610065，China；2. College of Architecture and Environment，Sichuan University，Chengdu，Sichuan 610065，China)
Abstract：In order to study dynamic propagation of mode I cracks under blast loads，a rectangle plate specimen with a crack，prepared by PMMA with good homogeneity and transparency，was proposed in this paper. The experimental system consists of a high dynamic strain amplifier，an oscilloscope，a constant source，strain gauges and crack propagation gauges. The strain gauges and crack propagation gauges(CPGs) were used to measure the blast load and crack propagation speed respectively，and the scanning electron microscope was applied in studying the property of the fracture surface. AUTODYN was applied in simulating crack dynamic propagation behavior. The JWL equation of state(EOS) and a linear EOS were respectively applied to describe the explosive detonation products and the relationship between the pressure and density of PMMA. A modified principle stress failure criterion was employed to assess the material state. Based on displacement extrapolation method，a numerical model was established in ABAQUS code to acquire dynamic stress intensity factors at the crack tip. The experimental and numerical results show that the propagation of mode-I cracks under blast stress wave can be divided into stable propagation and unstable propagation stages，Fracture surface roughness will decline with crack propagation in the stable propagation stage and fracture surface is relatively smooth in the unstable propagation stage. It is also revealed that crack propagation velocity varies in a certain range in the stage of crack stable propagation.
万端莹1，2，朱哲明1，2，刘瑞峰1，2，刘 邦1，2，李剑飞1，2. 基于RPC试件的爆炸应力波作用下I型裂纹扩展行为的研究[J]. 岩石力学与工程学报, 2019, 38(12): 2478-2490.
WAN Duanying1，2，ZHU Zheming1，2，LIU Ruifeng1，2，LIU Bang1，2，LI Jianfei1，2. Study of propagation behaviors of mode I cracks under blasting stress#br# wave based on RPC specimens. , 2019, 38(12): 2478-2490.
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2019, Vol. 38 
