Ballistic resistance of ultra high performance concrete plates

In recent years, terrorist activities have been increasing worldwide. These attacks, which target military and civilian buildings, not only cause structural damage, but also lead to massive loss of life and property. For this reason, the development of new generation construction materials with high performance and resistance to extreme loads is of great interest to researchers and engineers. The ballistic performance of concrete, the most widely used construction material in the world, is of great importance for military and civilian structures. In recent years, Ultra High Performance Fiber Reinforced Concrete (UHPFRC), which has superior mechanical properties compared to conventional concrete, has started to be used in the design of defense structures. In this study; it is aimed to increase the resistance of concrete against armed attacks by adding fibers to concrete. For this purpose, the ballistic performances of UHPFRC mixtures developed using different types of new generation steel fibers were investigated. In this context, plate elements with dimensions of 325x325 mm and 80 mm thickness were produced using three different concrete mixtures and the effects of these plates on ballistic performance were investigated. As a result, it was determined that the fiber-free concrete produced as a reference was damaged more than the specimens with 2% and 3% steel fibers in the crater depth and equivalent crater diameter parameters. These results indicate that reinforcement of concrete with steel fibers distributed homogeneously throughout the concrete provides superior ballistic performance. It was observed that compressive strength increased with increasing fiber content by volume, while crater diameter and crater depth decreased.