Numerical analysis on fire performance of sandwich composite wall with truss connectors

Based on the previous experimental study on sandwich composite walls with truss connectors under axial loads and one-side fire, finite element analysis was conducted on the fire performance of the novel wall in this paper. Firstly, a thermal coupling analysis model was established for the sandwich composite wall by the finite element software ANSYS, and simulation of test results was performed. The comparison between the predicted results and the test results showed that this model could accurately simulate behaviors of sandwich composite walls under fire. The validated finite element analysis model was utilized to carry out parametric analysis on the fire performance of the sandwich composite walls under one-side fire and two-side fire, respectively. Results showed that wall thickness is a major parameter affecting the fire resistance of the wall under one-side fire. The axial compression ratio, the height-thickness ratio and the wall thickness are major parameters influencing the fire resistance of the wall under two-side fire. Equations for predicting the fire endurance of sandwich composite walls were obtained, by fitting with the major affecting parameters. The calculated results from the equations were in good agreement with the results from the finite element simulation, and the equations can be used as a reference for the fire-resistant design of sandwich composite walls.