Effect of test methods on the performance of fiber reinforced concrete with different dosages and matrices

Hetemoğlu, Yalçın Oğuz
Through the last few decades, the idea of adding fibers in to concrete has been quite improved, considering the significant contribution of fibers to the mechanical properties of concrete such as tensile strength, energy absorption capacity and ductility. As a result of many intensive research Fiber Reinforced Concrete (FRC) has become a high-tech material that ensures great performance yet needs efficient design and application. However, the lack of a universally accepted approach and standardized test method for the performance analyses of FRC is one of the main obstacles in the process of providing the optimum combination between the fiber type, fiber volume and the matrix character of the concrete. This study investigates the performance of polypropylene fiber reinforced concrete with fiber dosages of 3, 6 and 9 kg/m3 for two different types of concrete, high performance and pervious concrete, by determining the energy absorption capacities through centrally loaded round and square panel tests. For this scope, three specimens for each concrete type and shape were prepared and tested under displacement control mode to obtain the load deflection curve for each specimen. The energy absorption capacities were then calculated for a displacement up to 25 mm. The two test methods also were compared considering the energy absorption capacities, cracking lengths and variability of test results. Then energy relationship between these two test methods was formulated.