The present paper investigates the capability of Nonlinear Finite Element Analysis (NLFEA) in predicting the behavior of Reinforced Concrete (RC) members subjected to combined gravity and temperature loads. The experimental and NLFEA results show that temperature changes have notable influence on the initiation of cracking, the stiffness degradation and ultimate load-carrying capacity. The NLFEA outcomes were compared to the experimental data of RC beams subjected to uniform and through-thickness temperature gradients. The NLFEA modelling technique, presented in this paper, reasonably well simulated the load–displacement history, cracking patterns and failure modes. Cracking loads and ultimate capacities for all tested specimens were estimated within 10% of the experimental data. In some cases, there was a slight overprediction of cracking loads and slight under-prediction of ultimate strengths; however, the agreement was generally consistent. Mesh sensitivity studies proved that the NLFEA solution converged and showed more accurate results as the discretization is refined. The conclusions emphasize the significance of considering nonlinear material behavior, tension stiffening and differential thermal expansion of steel and concrete for the thermo-mechanical analysis. In summary, the results indicate that the proposed NLFEA model offers a robust and accurate prediction of RC structural behavior under combined thermal and gravity loading.
