COMPLEX STRESS INTENSITY FACTORS FOR A CRACK IN A BIMATERIAL BRAZILIAN TEST SPECIMEN

The stress field in front of a crack tip lying in a plane bimaterial i nterface is always of a complex nature. The stress intensity factor ch aracterising its asymptotic variation is therefore a complex number an d its assessment from a numerical calculation requires the separation of the particular loading modes by an appropriate method. A suitable m ethod is provided by the combination of curve integrals and an auxilia ry singular field, enabling this separation by means of simple post-pr ocessing. This method can also be applied to the separation of load mo des in front of the crack tip in a homogeneous specimen exposed to a m ixed-mode load.