Calculation and Analysis on the Thermal Damage at High Temperature

Abstract:

In fire resistant design traditional method based on experiment is being replaced by method based on calculation.in this paper Damage mechanics is applied to calculate and analyze the process of damage and failure of structures at high temperature through solving jointly the closed equations composed of the thermal damage evolving equation based on the residual strength, heat conduction equations, equilibrium equations, geometry equations and physics equations. An example of a truss is given to illustrate the calculation of thermal damages and stresses at high temperature. The results suggest, the bearing capacity at high temperature is influenced by these three main factors: thermal damage resulted from the elevated temperature, the thermal stresses and the original load. This provides a new research method for the modern fire-resistant design based on calculation and can be developed and applied in the numerical simulation of the process of damage and failure of the integrated structures.