Fracture Toughness of Concrete by using Recycle Aggregates in Addition with S2 Glass Fiber

Abstract

The scarcity in conventional material to prepare concrete and a demand of reuse of demolished or abandoned waste of concrete structure gives a reason to study the ways of using more amount of recycled aggregates. Various studies reviewed the use of recycled aggregates but to a maximum limit of 50% whereas use glass fibers gave a better response to mechanical and chemical properties of concrete 1. For concrete the occurrence of cracks and pores is uncertain and it is important to investigate whether they are intact or not. The durability of the fracture tests depends on the ductile nature of concrete structures under load. It was found that there is a need to assess the strength of the concrete at fracture of the critical point. The present study aims at finding out how far the ductility of concrete with recycle aggregates can be improved by the addition of S2 glass fibers in terms of fracture toughness by varying the fiber content. The research work consist of replacement of recycle aggregates with five different mixes of concrete as 40, 60, 70, 80 & 100% and in each five mixes the addition of S2 glass fiber with 0.25%-1% by its weight with an increment of 0.25% is done. 3 point bending test on notched beams were conducted for determination of critical stress intensity. The tests were performed as per the guidelines of International Union of Laboratories and Experts in Construction Materials, Systems and Structures (RILEM) 5.The research paper gives idea about optimum percentage of recycle aggregates and S2 glass fiber that can be used in concrete structures casting taking in account the study of fracture toughness.