بررسی میدانی، آزمایشگاهی و عددی اثر همزمان افزایش چگالی بتن و تقویت با الیاف فولادی دو سر قلاب بر مقاومت بتن در برابر انفجار

Resistance to explosive loads is one of the most important aspects of the design of critical structures due to the wide range of threats. With the widespread use of concrete in the development of explosion-resistant structures, there is much research on the response of concrete components against dynamic loads such as explosion and impact in the technical literature. This paper experimentally and numerically investigates the simultaneous effect of increasing the density of concrete and reinforcing it with hooked-end steel fibers against blast caused by the high explosive pentolite mixture (C-4). In this regard, a total of 150 cubic and cylindrical concrete specimens containing steel fibers in different volume fractions (0, 0.5, and 1%) were made to evaluate the physical and mechanical properties of normal-weight (NW) and heavyweight (HW) concrete. After examining the NW and HW concrete mix designs in the laboratory, blast field tests were conducted by directly attaching the explosive on a set of six concrete blocks with dimensions of 50×50×10 cm fabricated with optimal mix designs of both concrete types. Subsequently, numerical modeling of the concrete behavior against blast load was performed using LS-DYNA finite element software to validate the examined parameters, and then the modeling output was compared with laboratory and field results. The results obtained from the finite element modeling indicate an acceptable agreement with field observations and laboratory results.