Experimental and numerical investigation on thermomechanical behavior of diverse plain-woven CFRP bolted joint configurations

This paper aimed at investigating the thermomechanical behavior of four types of plain-woven CFRP bolted joints, namely open-hole tension (OHT), CFRP-CFRP single-lap single-bolt joint (CCSSJ), CFRP-Al alloy single-lap single-bolt joint (CASSJ), and CFRP double-lap single-bolt joint (DSJ). Building on authors’ previous experimental work on the CCSSJ and CASSJ, additional quasi-static tensile tests were conducted on the OHT and DSJ of the same plain-woven CFRP system at -50 °C, 23 °C and 120 °C, and temperature sensitivity of the four configurations was systematically compared. To simulate the thermomechanical damage growth processes of the four configurations at -50 °C, 23 °C and 120 °C, thermomechanical progressive damage models (TMPDMs) were developed by comprehensively incorporating temperature-dependent constitutive relationships, delamination propagation, composite shear nonlinearity, continuum damage mechanics-based stiffness degradation, bolt torque, and bolt thread modeling. It is found that the developed TMPDMs demonstrate high predictive accuracy for joint performance, typical stage features and failure mode across all investigated cases, with maximum deviations of 14.6 % in joint maximum load. Then, the differences in failure mechanisms across joint configurations under varying temperatures were thoroughly analyzed and discussed.