尖锐V型切口混凝土梁的应力强度因子研究

Abstract

The failure behavior of the concrete beams with V notches is usually predicted by the notch stress intensity factor (NSIF), which quantify the intensities of the asymptotic linear elastic stress distributions around the notches. For a V-notched beam, the NSIF is determined by the notch angle. The strain energy density fracture criterion is used to judge the fracture failure of a member according to whether the strain energy density in a certain volume reaches the critical value. If the volume is small enough to neglect the higher-order solutions of the Williams equation, the strain energy density criterion can be used to calculate the NSIF. In view of the type-Ⅰ load condition, the theoretical NSIFs of the V notches obtained with the mean strain energy density fracture criterion and Carpinteri’s finite fracture mechanics method respectively, agree well with each other. Moreover, both the theoretical NSIFs given by the 2 criteria are fairly consistent with the experimental results from various V-notched concrete beam specimens.