Understanding the response of reinforced concrete slabs due to contact explosion of TNT
Evaluating response of reinforced concrete (RC) structures to blast loads is now a matured field of research. The United Facilities Criteria (UFC) 3-340 design manual and similar other manuals lay out the design practice for blast resistant structures. However, most of the design methodologies are restricted to far-field (scaled distance > 1.18 m/kg 1/3 ) blast loading. The semi-empirical charts and equations presented in design manuals for far-field blast loading are not accurate in the near-field events and furthermore very little research is available on contact explosions. Contact explosions are more complex than the far-field explosion effects due to the spatially and temporally non-uniform overpressure. There are limited experimental studies available in the literature as many gauges do not survive the harsh near-field environment. Thus, most finite element models in the near-field events are validated based on post blast damage photos. This paper presents the results from field tests conducted on RC slabs with embedded piezo-electric based concrete vibration sensors (CVS). A correlation has been shown between the concrete strains and the voltage recorded by the sensors. These results have further been compared to the numerical results obtained from LS-DYNA. The contact explosion was modeled using the arbitrary-Lagrangian-Eulerian (ALE) element formulation. The study shows that contact explosion can be reliably modeled using the presented parameters. The readings obtained from CVS could capture the shock wave propagation and the strain time history in the slab at required locations.
|Conference||6th International Conference on Engineering Mechanics and Materials 2017|
Dua, A. (Alok), Braimah, A, & Matsagar, V. (Vasant). (2017). Understanding the response of reinforced concrete slabs due to contact explosion of TNT. In 6th International Conference on Engineering Mechanics and Materials 2017 (pp. 1021–1030).