Study of Fiber Synergy in Ultra High Strength Concrete

Fibers are the materials having uniaxial strength, especially in tension. As per literature addition of fibers in discrete manner to the concrete will enhance some of the mechanical properties. The interaction between fiber and concrete alters the ductility of the concrete. Fibers prevent the early cracking of concrete due to plastic shrinkage and drying shrinkage. They reduce the permeability and bleeding of concrete. Concrete is relatively brittle than steel and its tensile strength is about one tenth of its compressive strength. In order to overcome this disadvantage, the concrete is reinforced with small, randomly distributed fibers. If one type of fiber is used in the concrete it is called mono fiber. The mono fibers improve the mechanical properties of concrete. The present experimental investigation is carried out to quantify the improved mechanical properties for different amounts of fibers for M70 grades of concrete. The properties studied are compressive and splitting tensile strengths, modulus of rupture and toughness.