多裂纹扩展的扩展有限元法分析_石路杨.pdfVIP

35 1 Vol.35 No. 1 2014 1 Rock and Soil Mechanics Jan. 2014 (2014) 01 0263 10 210098 Lagrange 1 2 Lgrange TU 457 A Analysis of multiple crack growth using extended finite element method SHI Lu-yangYU Tian-tang Department of Engineering Mechanics, Hohai University, Nanjing 210098, China Abstract: The extended finite element method of multiple crack growth is presented. The crack junction is analyzed using the junction enrichment function; th e generalized nodal shape functions are used in a cluster of nodes around the cracks, a ramp function is used to avoid the blending element problem. These techniques can effectively improve the accuracy of stresses in the vicinity of crack. The mortar method (segment-to-segment contact approach) in combination with the augmented Larange method is adopted to establish the contact conditions between crack faces. Thus the contact is modeled precisely; and it is convenient to solve the control equations. Several numerical examples are analyzed as follows: (1) computing the stress intensity factors of the cross crack, the proposed method can obtain higher accuracy; (2) simulating the growth and coalescence of multiple cracks, the numerical results are good in agreement with the experiments; it shows the reliability of the present method. Key words: multiple cracks; extended finite element method;