Material properties, including mechanical properties and thermal properties, are important factors in the analysis of concrete at elevated temperature. When subjected to elevated temperature, a particular strain called transient strain develops in concrete. Implicit form of transient strain is incorporated in Eurocode 2 which makes it inappropriate to be used in the predicting of thermal deformations of concrete components during cooling stage. The explicit model of thermal strains is studied and used to establish the new modulus of elasticity of concrete at various high temperatures. The main results of this study are :
1. The temperature distribution at surface and inner portions of the beam is in good agreement with the experimental results done by Prof Fang I-Kuang and his students at National Cheng Kung University[5].
2. Deformation of the beams based on the new modulus of elasticity according to the explicit model of thermal strains agrees better with the experimental results [5] comparing to the deformation based on implicit model of Eurocode 2.

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