Numerical Analysis of RC Members under Blast Loads Based on Moment-Curvature Relationship

Abstract

Interest in the safety of structures subjected to blast loading is increasing as bombing attacks and unexpected explosions. Since the explosion causes critical damage to structures and loss of human lives, the accurate prediction of the behavior of structures under blast loading to ensure the safety of structures. The material properties under the high strain rate condition such as blast loading condition are different from properties in quasi-static state. A numerical model for the dynamic nonlinear analysis of RC members subjected to blast loadings is introduced on the basis of the moment-curvature relationship. In general, the dynamic increase factor(DIF) is defined in terms of the strain rate in the stress-strain relation of materials. A DIF equation is constructed as a function of the curvature rate in the moment-curvature relation of the RC section in this paper. The moment-curvature relationship is modified to consider the bond-slip effect. The shear stress-slip relationship from experimental data is implemented to describe the direct shear behavior under blast loadings with high pressure and short duration. Correlation studies between analytical results and experiments are conducted to establish the validity of the proposed model. Parametric studies is conducted to identify the influence of factors on RC members subjected to blast loads.