SHCC-strengthened RC panels under near-field explosions

Abstract

Recurrence of recent activities in terms of accidental and premeditated explosions around the world has drawn the attention of the engineering community to assess the vulnerability of existing infrastructure under blast loading and find suitable repair and retrofitting technologies. Thus, this study focuses on the application of strain-hardening cementitious composite (SHCC) as a strengthening material by evaluating the response of SHCC-strengthened reinforced concrete (RC) panels under near-field explosions (scaled distance around 0.58 m/kg1/3) by spherical trinitrotoluene (TNT) charges as till now no study was conducted in this area. In total 5 panels, 1 control panel and 4 strengthened panels were tested under the same blast loading conditions. Two retrofit schemes (i.e., ‘distal surface only’ and both ‘blast-incident and distal surfaces’) were employed to retrofit the panels with a layer of SHCC. It was observed that the SHCC-strengthened panels perform better as compared to the control panel. Multi Material Arbitrary Lagrangian Eulerian (MMALE) with fluid-structure interaction (FSI) and Load Blast Enhanced (LBE) methodology available in LS-DYNA program were used to validate the blast wave parameters. Finally, three dimensional nonlinear finite element (FE) models were developed to compare the blast responses of the control and strengthened RC panels. This study as a whole will provide a guideline to the researchers and practicing engineers to deal with the blast retrofitting of RC structures.