New M.E.Thesis Submitted from Civil

Unified Flexural Design for SFRC Beams by Lovepreet Singh

Abstract

Concrete is a stuff that requires strengthening in tension so as to fulfil the structural needs. New techniques are developing day by day in order to strengthen concrete besides the use of steel reinforcements. Fibre reinforcement technique is prevalent since few decades but yet there are no unique guidelines available for design using this technique and it is still unknown with the community. In this study, two guidelines that are RILEM TC-162-TDF and CNR-DT 204, proposed in 2006 are used to formulate a common design procedure. The purpose of this research is to propose a flexural design procedure for SFRC beams. In this study, an analytical model is developed for flexural capacity of SFRC beams having a rectangular section. The formulated model assumed an elastic perfect-plastic model for compression as well as a linear post cracking behaviour for tension. The proposed model is validated with experimental results. This study is necessary to determine the experimental ultimate moment which is then compared with the ultimate moments depicted from various existing guidelines. For this study, the hooked end steel fibres with 1.5%, 1.75% and 2% volume fraction by concrete volume are used in concrete matrix having a constant aspect ratio of 60. Cubes and beams were casted with a different volume fraction of steel fibres. After 28 days standard curing, the compression and flexure tests are done on cubes and beams respectively. It is observed from the results that as the fibre content is increased, the compressive and flexural strength of concrete also improves. By using the experimental data obtained from experiments in the proposed expression, it is observed that the RILEM TC-162-TDF and CNR-DT 204 provide the satisfactory results with the experimental moment.    .