Influence of Designed Lateral Constraints on 3D Crack Propagation: A Quasi-Static Phase-Field LEFM Approach

Abstract

Many modern crack deflection and control strategies are material dependent and are often simplified to two-dimensional frameworks, while three-dimensional effects remain essential in fracture mechanics. By exploiting out-of-plane or three-dimensional effects without modifying the material itself, this work investigates the influence of designed lateral constraints on three-dimensional crack propagation using a quasi-static phase-field linear elastic fracture mechanics (LEFM) approach. Simulations conducted in FEniCSx under Mode I loading show that lateral constraints alter the local stress field and influence crack behavior, including crack pseudo-velocity, but do not significantly alter crack trajectory despite variations in patch size, location, and slab thickness. In contrast, tensile displacement constraints demonstrate greater potential for inducing crack deflection, although they may introduce unfavorable stress concentrations elsewhere in the structure. These results highlight the limitations of lateral constraints for crack steering and motivate further development of more effective out-of-plane lateral constraint-based strategies.