Analysis on the stress intensity factor(SIF)for mixed-mode crack atbottom base layer with weight functions expressed with matrix

Due the variations of materials, shrinkage of base layer(especially the cementitious binder is used), temperature stresses, poorly compacted soil, poor constraction and poor maintenance and the mixed-mode loads subjected to the pavement, mixed-mode cracks are easy to occur at the bottom of the base layer of pavements, so it is necessary to analyze the stress intensity factors for the mixed-mode cracks at the bottom of base layer.The method to calculate the mixed-mode stress intensity factors is derived with the matrix weight functions according to the energy rule, superpostition theory and Betti's reciprocity theory.The method to get the constant coefficients of weight functions is also analyzed, which is based on the SIFs by finite element method.The weight functions are checked by the finite element method, and the agreement appears to be fairly good for the whole results by the two methods, which reveals the weight function method is very efficient.Thecorresponding programs arealso made, and it will be useful for analysis on the reflecting cracks in pavements and the engineering applications.