This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements...This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements for displacement and stress are derived.An exponential transformation technique is introduced to accurately calculate the nearly singular integral,which is the key task of the boundary element simulation of thin-walled structures.Three numerical experiments with different types of cracks are provided to verify the performance of the present numerical framework.Numerical results demonstrate that the present scheme is valid for modeⅢcrack problems of thin-walled structures with the thickness-to-length ratio in the microscale,even nanoscale,regime.展开更多
This paper presents a hybrid Trefftz （HT） boundary element method （BEM） by using two indirect techniques for mode III fracture problems. Two Trefftz complete functions of Laplace equation for normal elements and a...This paper presents a hybrid Trefftz （HT） boundary element method （BEM） by using two indirect techniques for mode III fracture problems. Two Trefftz complete functions of Laplace equation for normal elements and a special purpose Trefftz function for crack elements are proposed in deriving the Galerkin and the collocation techniques of HT BEM. Then two auxiliary functions are introduced to improve the accuracy of the displacement field near the crack tips, and stress intensity factor （SIF） is evaluated by local crack elements as well. Furthermore, numerical examples are given, including comparisons of the present results with the analytical solution and the other numerical methods, to demonstrate the efficiency for different boundary conditions and to illustrate the convergence influenced by several parameters. It shows that HT BEM by usingthe Galerkin and the collocation techniques is effective for mode III fracture problems.展开更多
This paper deals with an infinite slab with a semi-infinite crack,which is subjected to the anti-plane shear k_Ⅲ field at infinity.The slab is made of an elasto-damaged material.Analytical solution is obtained by use...This paper deals with an infinite slab with a semi-infinite crack,which is subjected to the anti-plane shear k_Ⅲ field at infinity.The slab is made of an elasto-damaged material.Analytical solution is obtained by use of conformal mapping.The shape of damaged-zone,the dissipative energy,the shear open- ing displacement on the crack surface and several stress distribution curves are given.The far field condition is checked,The asymptotic behavior near the crack-tip is given.展开更多
基金supported by the National Natural Science Foundation of China(No.11802165)the China Postdoctoral Science Foundation(Grant No.2019M650158).
文摘This paper develops a new numerical framework for modeⅢcrack problems of thin-walled structures by integrating multiple advanced techniques in the boundary element literature.The details of special crack-tip elements for displacement and stress are derived.An exponential transformation technique is introduced to accurately calculate the nearly singular integral,which is the key task of the boundary element simulation of thin-walled structures.Three numerical experiments with different types of cracks are provided to verify the performance of the present numerical framework.Numerical results demonstrate that the present scheme is valid for modeⅢcrack problems of thin-walled structures with the thickness-to-length ratio in the microscale,even nanoscale,regime.
基金the National Natural Science Foundation of China(10472082).
文摘This paper presents a hybrid Trefftz （HT） boundary element method （BEM） by using two indirect techniques for mode III fracture problems. Two Trefftz complete functions of Laplace equation for normal elements and a special purpose Trefftz function for crack elements are proposed in deriving the Galerkin and the collocation techniques of HT BEM. Then two auxiliary functions are introduced to improve the accuracy of the displacement field near the crack tips, and stress intensity factor （SIF） is evaluated by local crack elements as well. Furthermore, numerical examples are given, including comparisons of the present results with the analytical solution and the other numerical methods, to demonstrate the efficiency for different boundary conditions and to illustrate the convergence influenced by several parameters. It shows that HT BEM by usingthe Galerkin and the collocation techniques is effective for mode III fracture problems.
基金The project supported by National Natural Science Foundation of China
文摘This paper deals with an infinite slab with a semi-infinite crack,which is subjected to the anti-plane shear k_Ⅲ field at infinity.The slab is made of an elasto-damaged material.Analytical solution is obtained by use of conformal mapping.The shape of damaged-zone,the dissipative energy,the shear open- ing displacement on the crack surface and several stress distribution curves are given.The far field condition is checked,The asymptotic behavior near the crack-tip is given.
