EVALUATION OF MODE I STRESS INTENSITY FACTOR OF ROCK UTILIZING DIGITAL SPECKLE CORRELATION METHOD
DAI Shuhong1，2，MA Shengli1，PAN Yishan2，DONG Zixian2
(1. State Key Laboratory of Earthquake Dynamics，Institute of Geology，China Earthquake Administration，Beijing 100029，China；2. School of Engineering and Mechanics，Liaoning Technical University，Fuxin，Liaoning 123000，China)
Abstract：An automatic method for determining mode I stress intensity factors(SIFs) and crack tip positions of rock specimens from displacement fields obtained by digital speckle correlation method(DSCM) is proposed. Notched semicircular disk granite specimen under three-point bending are employed for determining the mode I SIFs and the displacement fields around crack tip which are measured by DSCM. Nonlinear displacement field equations with unknown parameters are solved by Newton-Simpson method. The research results show that mode I SIFs，crack tip positions and crack propagation length can be determined accurately from the components of displacement fields；and the characters of rock fracture and crack propagation are revealed. The present method settled the problem of determining stress intensity factors and crack tip position simultaneously in rock fracture testing；so the fracture parameters of rock can be calculated.
代树红1，2，马胜利1，潘一山2，董子贤2. 数字散斑相关方法测定岩石I型应力强度因子[J]. 岩石力学与工程学报, 2012, 31(12): 2501-2507.
DAI Shuhong1，2，MA Shengli1，PAN Yishan2，DONG Zixian2. EVALUATION OF MODE I STRESS INTENSITY FACTOR OF ROCK UTILIZING DIGITAL SPECKLE CORRELATION METHOD. , 2012, 31(12): 2501-2507.
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2012, Vol. 31 
