Experimental Study on GFRP Strips Strengthened New Two Stage Concrete Slabs under Falling Mass Collisions

Abstract

In the course of global terrorist events prominent risks were faced by military and civilian infrastructure. Subsequently, the design of structures to resist impact load has become vital in the design process. Fibre reinforced polymer sheets were utilized as exceptional material to enhance the resistance of the structure to impact load. Until now, most researchers focused on the response of Fibre Reinforced Polymer (FRP) strengthened slabs under static load. Extensive research on the impact response of FRP strips strengthened slabs is relatively rare and the outcome of these investigations have been controversial. Therefore, it is vital to comprehend the response of FRP strengthened slabs subjected to falling mass collisions. In this study, impact response of Glass Fibre Reinforced Polymer (GFRP) strips strengthened Two Stage Reinforced Concrete Slabs (TSRCS) have been examined through experiments. Two different widths of 50 mm and 75 mm GFRP strips were used in perpendicular and oblique ways in one and two directions while strengthening TSRCS. In Total, a nine 1,000 mm × 1,000 mm × 60 mm TSRCS were fabricated and later impacted by a steel cylinder of 55 kg dropping at the centre from a 3,000 mm height. Study parameters analysed to discover the impact response of TSRCS include, impact-force history, acceleration, damaged area (top and bottom face), damage area ratio, damage volume ratio, and damage pattern. The results revealed that the slab strengthened with 75 mm GFRP strips was more effective in alleviating damage volume ratio compared to the 50 mm GFRP strips. Also, the obtained results in this study shed light on the impact performance of two stage reinforced concrete slabs.