Flexural Strength of Steel Fiber Ultra High Strength Concrete Beams under Static and Repeated Loads

Abstract

The goal of the present work is to study the performance of Ultra High Strength Concrete (UHSC) beams in flexure under static and repeated loads. The main considered variables are the main reinforcement ratios which are (0.0129, 0.0204, and 0.0323), and the method of applying load. For each reinforcement ratio two beams were casted, one of them was tested under four points static load and the other one under repeated load up to failure. The behavioral characteristics of Ultra High Strength Concrete dominantly depends upon its load history, for this purpose experimental investigation of the behavior of (UHSC) beams under load history of repeated cycles is performed as well as that it is compared with the behavior under static load. The average cube compressive strength of the UHSC used in casting the beams was as high as (124 N/mm2). The load deflection curves, first cracks and failure loads, crack pattern, and concrete strain distribution over the depth of the beams were presented.