Behavior of Prestressed Concrete Strengthened with and without SFRC Beams Subjected to Fatigue Loading

摘要

A substantial number of prestressed concrete structures such as bridge deck slabs, bridge girders, airport runways, or marine installations are often subjected to fatigue loading during their service life. These loads can result in a steady decrease in the stiffness of the structure and increases the risk of fatigue failure of prestressing strands through undergoing millions of cyclic loads. Use of steelfiber reinforcement concrete (SFRC) materials for strengthening of structural members has become an increasingly popular area of research and application for concrete reinforcement in the last decade. However, very little work has been undertaken to determine their effectiveness for strengthening prestressed concrete. This experimental study is proposed to investigate the efficiency of using steel fibers to improve load carrying capacity and fatigue performance of prestressed concrete beam subjected to cyclic loading. Two prestressed concrete beam specimens of 180 mm in width, 250 mm in depth and 3500 mm in length were tested with steel fiber contents of (zero and 3 %) by volume of concrete, under constant amplitude cyclic and static loading. Based on the experimental results, it can be seen that the load carrying capacity of steel fibre increased by approximately 22% than the Plain prestressed concrete beam.