Compression‐After‐Impact Performance of CFRP Laminates With Pre‐Embedded Delamination Subjected to Low‐Velocity Impact and Bolted Reinforcement

ABSTRACT This study investigates the compression‐after‐impact (CAI) performance of carbon fiber‐reinforced polymer (CFRP) laminates containing pre‐embedded delamination and subjected to low‐velocity impact (LVI). Experimental tests were conducted on various laminate configurations, including intact, delaminated, and bolted‐repaired specimens. Bolted repairs were found to significantly enhance compressive strength across all configurations, with improvements ranging from 5.8% to 12.2% compared to undamaged specimens, highlighting their effectiveness in restoring load‐bearing capacity. Experimental analysis also showed that delamination depth critically affected CAI strength, with near‐surface delaminations causing the greatest performance degradation. Furthermore, stacking sequence architecture—especially the distribution of 0° unidirectional and woven fabric plies—proved more influential than overall symmetry in determining residual strength. A finite element model was developed to complement the experiments by combining Puck failure theory for intralaminar damage with a cohesive zone model (CZM) for interlaminar delamination. The simulation results showed excellent agreement with the experimental data, confirming the accuracy and reliability of the numerical framework. Based on this validated approach, the model was further applied to investigate the effects of delamination size at mid‐thickness in symmetric laminates and stacking sequence asymmetry. The results successfully captured the transition from global to localized buckling as delamination size increased and reproduced the strength degradation observed in reversed asymmetric configurations (A ⁻ and B ⁻ ), which were affected by unfavorable surface ply layouts. These outcomes demonstrate the effectiveness of the model in evaluating impact‐induced damage and CAI performance in composite laminates.