DELAMINATION OF BEAMS UNDER TRANSVERSE-SHEAR AND BENDING

Two delamination problems are studied: a straight beam of rectilinearl y orthotropic material under transverse loading and a curved beam (or C-specimen) with cylindrical material anisotropy under pure bending. R esults are presented for each problem for the dependence on the crack length of both the energy release rate and a measure of the relative a mount of mode LI to mode I. The number of nondimensional parameters in the problems is fairly large, including two dimensionless elasticity parameters. Considerable simplification of the parametric dependence i n the straight beam problem is achieved using an orthotropic rescaling technique due to Sue. Asymptotic solutions based on elastic beam theo ry are also presented. A by-product of the present analysis is the fin ding that frictionless contact of the crack faces near one of the crac k tips has little effect on the other tip, even in the case when the s ize of the contact zone is large relative to the length of the crack.