Stress Analysis of Slabs Reinforced with GFRP Rebar

Abstract

Designed constructions must meet a certain level of safety and durability. They should also be designed in accordance to Ultimate Limit State and Serviceability Limit State with respect to profitability for the contractor. During designing stage of reinforced concrete, it is important to remember that the values in static and strength calculations are assumed as ideal. In reality, material properties of steel and particularly concrete are biased with a certain degree of random. Modern technologies allow to utilize construction materials with strictly determined deformation and mechanical parameters. Significant development of concrete technology in recent years poses new challenges. In the study, authors used Glass Fibre Reinforced Polymer rebar as a replacement for standard steel rebar. The article presents the results of the destruction tests of concrete slabs reinforced with steel and GFRP rebar. The tests were performed on 14 slabs with length-to-width ratio of 4. The thickness of slabs ranged from 6 to 10 cm. In nine slabs, authors replaced the standard rebar with GFRP rebar. The tests involved stress analysis in rebar and concrete. The secondary goal was to determine the bearing capacity and deflection of slabs and assess the cracking of the sections during load application. Composite rebar has many advantages over standard rebar. However, due to a relatively low elasticity modulus in comparison to steel, the slabs exhibit excessive deflection and cracking of bended elements.