Objective CFRP (carbon fiber reinforced polymer) and GFRP (glass fiber reinforced polymer) have been applied to the structure of rail transit vehicle equipment cabin. Under impact loading, composite materials exhibit mechanical behaviors distinct from those under quasi-static loading. In view of the reduction in structural protection capability of the equipment cabin floor caused by ballast impact during service, it is necessary to conduct an in-depth study on the influence of strain rate effects of CFRP and GFRP on impact response.
Method A constitutive model of continuous fiber-reinforced composites considering strain rate effects is established, and a VUMAT (user-defined material subroutine) is developed based on the secondary development function of ABAQUS software. Dynamic tensile tests of CERP and GFRP are carried out, and dynamic enhancement factors are obtained by fitting the test results. Subsequently, dynamic tensile simulations of the two composite materials are conducted to verify the accuracy of the model and material parameters. On this basis, CFRP and GFRP are considered respectively as panel materials for the equipment cabin floor structure. According to the GB/T 32060—2015 standard, a simulation model of the aluminum projectile impacting the equipment cabin floor at an initial velocity of 200.00 km/h is established for calculation.
Result & Conclusion When CFRP is used as the panel material and the strain rate effect is considered, the residual velocity of the aluminum projectile increased from −52.16 km/h to −66.33 km/h, and the maximum panel displacement decreased by 9.69%. When GFRP is used as the panel material and strain-rate effect-is considered, the residual velocity of the aluminum projectile increased from −40.25 km/h to −48.87 km/h, and the maximum panel displacement decreased by 14.53%.
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