Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single...Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single inclined concentrated force at an interior point. The complex potentials are obtained based on a superposition principle, which provide the solutions to the plane problems of elasticity. The regular parts of the potentials are extracted in an asymptotic analysis. Based on the regular parts, Green’s function for the T-stress is obtained in a straightforward manner. Furthermore, Green’s functions are derived for a pair of symmetrically and anti-symmetrically concentrated forces by the superimposing method. Then, Green’s function is used to predict the domain-switch-induced T-stress in a ferroelectric double cantilever beam （DCB） test. The T-stress induced by the electromechanical loading is used to judge the stable and unstable crack growth behaviors observed in the test. The prediction results generally agree with the experimental data.展开更多
A method that uses finite element analysis to determine the non-singular stress （T-stress） at a crack tip is proposed in this study. T-stress includes two components： the Tx-stress parallel to the tangent of the cr...A method that uses finite element analysis to determine the non-singular stress （T-stress） at a crack tip is proposed in this study. T-stress includes two components： the Tx-stress parallel to the tangent of the crack at its tip and the Ty-stress perpendicular to this tangent. The effects of contact and friction on both the Tx- and Ty-stresses on the crack flanks are considered in the method. Because the method uses a single standard elastic finite element analysis derived directly from the equation of the stress fields around the crack tip and does not require any assumptions or simplification, it can be used to determine the T-stress for any given geometry and loading condition. Theoretical results are used to calibrate the results, which exhibited good agreement and to discuss the T-stress computational methodology. Furthermore, the Tx- and Ty-stresses in center-cracked Brazilian disc （CCBD） specimens subjected to diametrical or partially distributed compression were numerically computed, and the effects of contact and friction on the Tx- and Ty-stresses are discussed.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.10702071 and 11090334)the China Postdoctoral Science Foundation(No.201003281)+2 种基金the Shanghai Postdoctoral Scientific Program(No.10R21415800)the Shanghai Leading Academic Discipline Project(No.B302)sponsored by the"Sino-German Center for Research Promotion"under a project of"Crack Growth in Ferroelectrics Driven by Cyclic Electric Loading"
文摘Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single inclined concentrated force at an interior point. The complex potentials are obtained based on a superposition principle, which provide the solutions to the plane problems of elasticity. The regular parts of the potentials are extracted in an asymptotic analysis. Based on the regular parts, Green’s function for the T-stress is obtained in a straightforward manner. Furthermore, Green’s functions are derived for a pair of symmetrically and anti-symmetrically concentrated forces by the superimposing method. Then, Green’s function is used to predict the domain-switch-induced T-stress in a ferroelectric double cantilever beam （DCB） test. The T-stress induced by the electromechanical loading is used to judge the stable and unstable crack growth behaviors observed in the test. The prediction results generally agree with the experimental data.
基金supported by the National Basic Research Program of China(Grant No.2014CB047100)the National Natural Science Foundation of China(Grant Nos.51474046,U1562103)the Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(Grant No.SKLGP2014K017)
文摘A method that uses finite element analysis to determine the non-singular stress （T-stress） at a crack tip is proposed in this study. T-stress includes two components： the Tx-stress parallel to the tangent of the crack at its tip and the Ty-stress perpendicular to this tangent. The effects of contact and friction on both the Tx- and Ty-stresses on the crack flanks are considered in the method. Because the method uses a single standard elastic finite element analysis derived directly from the equation of the stress fields around the crack tip and does not require any assumptions or simplification, it can be used to determine the T-stress for any given geometry and loading condition. Theoretical results are used to calibrate the results, which exhibited good agreement and to discuss the T-stress computational methodology. Furthermore, the Tx- and Ty-stresses in center-cracked Brazilian disc （CCBD） specimens subjected to diametrical or partially distributed compression were numerically computed, and the effects of contact and friction on the Tx- and Ty-stresses are discussed.
