Numerical Simulations of Crack Growth from Surface Flaw under Uniaxial Compression
Surface faults, which extend from ground surface to a finite depth, are one of the common tectonic structures found on the earth surface. The mechanism of cracking from surface fault front differs significantly from cracking from the idealized 2-D fault model, which assumes fault extending infinitely into the earth crust. The crack emanating from pre-existing 3-D surface fault is still not fully understood. This paper summarizes our latest endeavor in simulating numerically crack growth from a pre-existing 3-D surface fault (referred as flaw hereafter) using the numerical code RFPA3D (Realistic Failure Process Analysis). The samples are modeled numerically as both heterogeneous (m=3.2) and homogeneous (m=1000) materials. The input parameters for the numerical sample are calculated according to the microcrack statistics method. Three observations were drawn from the numerical simulations: (1) under the axial loading, strong tensile stresses initiate along the flaw plane, particularly at the flaw front which is away from the middle portion of the flaw front; (2) the growth of wing crack dominates in homogeneous samples whereas anti-wing crack growth dominates in heterogeneous samples; (3) Petal cracks (or Mode III cracks) play an important role in the crack growth process form 3-D surface flaw. Anti-wing crack is developed by the growth of petal cracks from the interior of the flaw plane extending to the surface of the sample. The simulations closely resemble the experimental observations.
R.H.C.Wong S.B.Tang K.T.Chau C.A.Tang
Department of Civil and Structural engineering, The Hong Kong Polytechnic University, Hong Kong, chi Department of Civil and Structural engineering, The Hong Kong Polytechnic University, Hong Kong, chi School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian, Chinai
国际会议
香港
英文
1-5
2009-05-19（万方平台首次上网日期，不代表论文的发表时间）