Dependence of stress intensity factor on loading condition

Abstract

The problem of a centrally cracked rectangular plate is taken as a sample problem to evaluate the dependence: of the stress intensity factor on the loading condition. The total loading applied on the upper and lower edges is assumed to be 2 bp (2 b—the width of the plate). With the condition of the same total applied loading 2 bp along the upper and lower edges, the following conditions are imposed: (a) uniform tension with intensity p, (b) a pair of concentrated forces with intensity bp, (c) a type of tension-compression loading. A novel weight function approach is used to evaluate the stress intensity factor at the crack tip. From the numerical solution it is found that, with the condition of h b = 3.0 ( h b being the height width ratio of the plate) the maximum deviation of the stress intensity factor from the uniform tension case is 5.8% in the concentrated force loading case, and with the same condition the dependence of the stress intensity factor on the loading condition is negligible in the tension-compression loading case. However, in the case of h b ≤f 1.5 , the relevant dependence is significant.