文献类型：期刊文献

英文题名：Bridged cracks of mode III with surface elasticity

作者：Wang, Xu[1];Schiavone, Peter[2]

机构：[1]E China Univ Sci & Technol, Sch Mech & Power Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Univ Alberta, Dept Mech Engn, 4-9 Mech Engn Bldg, Edmonton, AB T6G 2G8, Canada

年份：2016

卷号：95

起止页码：125

外文期刊名：MECHANICS OF MATERIALS

收录：;EI(收录号：20161202128035);WOS:【SCI-EXPANDED(收录号:WOS:000372558000010)】；

基金：This work is supported by the National Natural Science Foundation of China (Grant no: 11272121) and through a Discovery Grant from the Natural Sciences and Engineering Research Council of Canada (Grant no: RGPIN 115112).

语种：英文

外文关键词：Surface elasticity; Crack bridging; Dugdale model; Cauchy singular integro-differential equations; Chebyshev polynomials; Collocation method

摘要：We examine the contribution of surface elasticity to a fully or partially bridged finite mode III crack. The surface effect is incorporated using the continuum-based surface/interface model of Gurtin and Murdoch. We assume that the bridging force is proportional to the crack opening displacement while the bridging stiffness is allowed to vary arbitrarily along the crack. By considering a distribution of screw dislocations on the crack, the problem is reduced to a first-order Cauchy singular integro-differential equation. After the expansion of both the unknown dislocation density and the known variable bridging stiffness into Chebyshev polynomials, the integro-differential equation is solved numerically using a collocation technique. A complete solution valid throughout the solid (including at the crack tips) is obtained. We identify two intrinsic material lengths: one associated with the surface elasticity and the other with the crack bridging. We find that the surface elasticity plays a predominant role when the crack is significantly shorter than the two intrinsic lengths. At the other extreme, the crack bridging plays a predominant role when the crack is considerably longer than the two intrinsic lengths. Numerical results are presented to demonstrate the significance of the solution. Finally, a consequence of our analysis is that the solution of the problem involving the Dugdale model of a mode III crack with surface elasticity is also readily available. Our results in this respect show that the determination of the size of the plastic zone is independent of the parameter characterizing the surface elasticity. (C) 2016 Elsevier Ltd. All rights reserved.