In this paper, the response of lightweight reinforced concrete (LWRC) beams under elevated temperature is numerically investigated using the nonlinear finite element software ABAQUS. Firstly, a numerical model is suggested and validated against experimental tests conducted by the authors. The validation results have shown the accuracy and reliability of the suggested numerical model. Thereafter, the validated numerical model was utilized in conducting a comprehensive parametric study to investigate the effects of several important parameters on the behavior and failure of normal and lightweight RC beams at elevated temperature. These parameters include the effect of the high ranges of elevated temperatures; the effect of heating rate; and the effect of thermal distribution along the beam length and around the beam section. The parametric study results have indicated that the distribution of the temperature along the beams length and around the beams section can affect the ultimate load resistance up to 5 and 4.93% for LWRC and NWRC beams, respectively.

本文利用非线性有限元软件ABAQUS数值研究了轻质钢筋混凝土（LWRC）梁在高温下的响应。首先，提出了一个数值模型，并针对作者进行的实验测试进行了验证。验证结果表明了所建议数值模型的准确性和可靠性。此后，使用经过验证的数值模型进行全面的参数研究，以研究几个重要参数对正常和轻型RC梁在高温下的行为和破坏的影响。这些参数包括高温范围的影响。加热速率的影响；以及沿光束长度和光束截面周围的热分布的影响。