Strain Rate Effect on the Response of Blast Loaded Reinforced Concrete Slabs

Kamel S. Kandil¹, Mouhamad T. Nemir¹, Ehab A. Ellobody², Ramy I. Shahin^1*

¹Department of Civil Engineering, Faculty of Engineering, Menoufiya University, Shibin El Kom, Egypt.
²Department of Structural Engineering, Faculty of Engineering, Tanta University, Tanta, Egypt.

DOI: 10.4236/wjet.2014.24027                

Abstract

Dynamic Increase Factor (DIF) due to strain rate effect was examined with documented experimental work done by Razaqpur, et al. In the experiment work, two 1000 × 1000 × 70 mm reinforced concrete slabs were constructed. The slabs were subjected to blast loads generated by the detonation of either 22.4 kg or 33.4 kg of ANFO located at a 3.0 m standoff. Blast wave characteristics, including incident and reflected pressures and reflected impulses were measured. The slabs were modeled by explicit analysis with or without strain rate effect to study their behavior under blast load to compare their predicted and observed behavior. The predicted post-blast damage and mode of failure for each model is compared with the observed damage of experimental work. It was concluded that when the dynamic increase factor added to concrete and reinforcement materials due to strain rate effect, the behavior of model under blast load become closer to experimental work.

Keywords

Explicit Analysis, Strain Rate, Blast Load, Ls-Dyna, Scaled Distance

Conflicts of Interest

The authors declare no conflicts of interest.

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