Abstract
The implicit form of the thermal strain of concrete recommended by Eurocode 2 is not appropriate for the modeling of the deformation of the reinforced concrete components during the cooling stage. This thesis use a proposed explicit form of thermal strains which separates the transient strain from other strains for the prediction of thermal deformations of columns during the heating and cooling stages. The experimental results of previous tests were then used to validate the analysis using ANSYS software.
The primary findings according to this study are as follows:
1) The creep strain of concrete at the elevated temperature is too small and can often be neglected. The sum of the instantaneous stress-related strain, creep strain and transient strain is smaller than the free thermal expansion. Therefore, the column under compression load experienced expansion during heating stage, and this is validated by test results.
2) The proposed modulus of elasticity based on the explicit model of the thermal strain for concrete can be use to predict reasonably the deformation of column during heating stage.

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