To gain a deeper understanding of the evolution laws governing material failure and damage, the crack initiation, propagation, and interaction mechanisms of brittle materials under various loading conditions were systematically studied using numerical simulations based on the peridynamic theory. The results demonstrate that the bond-based constitutive model derived from integro-differential equations can accurately predict complex fracture phenomena. Numerical simulations of two-dimensional tension tests with circular holes and three-point bending tests with offset cracks further validate its accuracy and effectiveness in simulating single crack propagation. Furthermore, pre-cracked double-crack systems under different initial inclination angles (30°, 60°, 90°) exhibit angle-dependent mechanical coupling mechanisms. As the inclination angle decreases, propagation modes transition from independent development to mutual interaction, presenting significant asymmetric characteristics. In addition, double cracks under small-angle configurations demonstrate evident cooperative failure features, ultimately forming interconnected fracture surfaces. The peridynamic numerical simulation method accurately predicts single crack propagation behavior and effectively simulates damage evolution and interaction mechanisms in multiple crack systems. These findings provide new theoretical foundations for analyzing complex crack behavior in brittle materials and assessing the safety of multi-crack structures.