Considerations on computational modeling of concrete structures in fire.

This paper presents an overview of selected issues in computational modeling for reinforced concrete structures in fire. The focus is on current modeling challenges, as well as aspects that are sometimes overlooked yet important for capturing the concrete material and structural behavior at elevated temperatures. Issues addressed include the consequences of realistic thermal exposures with cooling phases on the material properties and deformations, the uncertainties in material and structural response at elevated temperature, and the effect of the tensile fracture energy on the model response. The ability to capture membrane and shear failure modes is analyzed. The modeling of the residual response and potential failure during cooling is discussed. As an example, a five-story RC shear wall-frame building is modeled under natural fire. Finally, the paper ends with a discussion on the limits, research needs and opportunities with respect to computational modeling of concrete structures in fire. • The numerical modeling of concrete structures in fire is a complex endeavor. • Sensitivity of the predicted structural response in shear and membrane modes is discussed. • Tensile behavior and fracture energy are important yet insufficiently characterized. • Numerical failure (lack of convergence) must be distinguished from actual failure. • Still, (reasoned) adoption of numerical models offer great opportunities. [ABSTRACT FROM AUTHOR]