The purpose is to numerically study the behavior of a reinforced concrete frame up to failure considering explosive loads. For this, a recently developed generalized Timoshenko beam with embedded rotation discontinuity is adopted.

This research is mainly based on the previous results of Bitar et al [1].Within the framework of the finite element matlab code developed by Bonnet & Frangi [2], beam elements that incorporate strong discontinuities were implemented [1] so that the softening behavior and the crack opening are described, using a cohesive law that allows for capturing strength reduction and energy release. In this work, we extend the cohesive law, considering a general non-linear relation, in order to represent cyclic loading. Similar modifications were made concerning the generalized constitutive law linking the bending moment with the rotation, representative of a reinforced concrete section.

Loading on the structure due to explosions is described by a suitable blast pressure dependency on time. An estimation of this pressure distribution is obtained using the methodology developed by the U.S. Army Corps of engineers [3]. The effects of the fluid structure interaction are not considered. The efficiency of the proposed model is validated by comparisons with literature results.

References

 [1] Bitar, I., Kotronis, P., Benkemoun, N., & Grange, S. (2018). A generalized Timoshenko beam with embedded rotation discontinuity. Finite Elements in Analysis and Design, 150, 34-50.

 [2] Bonnet Marc, & Frangi Attilio. (2006). Analyse des solides déformables par la méthode des éléments finis. [Palaiseau]: Ed. de l'École polytechnique.

 [3] US Department of Defense (DoD). (2008). Unified facilities criteria: Structures to resist the effects of accidental explosions.