Experimental and numerical studies in the failure behavior of CFRP plates under combined compression-shear loading

The laminated carbon fiber reinforced polymer (CFRP) plate is the basic unit that forms thin-walled aircraft structures. It will suffer buckling or destruction under in-plane compression and shear loads, which then leads to the failure of the entire structure. To investigate the failure behavior of laminated CFRP plates under combined compression-shear loads, a uniaxially loaded fixture for compression-shear test was presented, which can apply different proportions of compression-shear loads to laminated plates. The test specimen and program were also developed, and the failure behavior of laminated CFRP plates under different compression-shear load ratios was investigated experimentally for the first time. Additionally, a progressive damage analysis model was developed to predict the failure of CFRP plates under compression-shear loads, and the model was validated by comparing the numerical results with the experimental results. Based on the proposed model, the effects of the compression-shear load ratio on the buckling, initial damage, and failure of the specimens were investigated. It is shown in the experimental and numerical studies that as the load ratio changes, the occurrence and extension of damage changes, leading to the competing phenomenon between buckling and stress-induced destruction failure of laminated plates under compression-shear loads.