Experimental evaluation of fiber reinforced concrete fracture properties

Concrete is now universally recognized a construction material vital and essential for the regeneration and rehabilitation of the infrastructure of a Country. The last few decades have now shown that high strength concrete, with a compressive strength of 100-120 MPa can be readily designed and manufactured. There have also been several advances made in the development of fiber reinforced concrete to control cracking and crack propagation in plain concrete. and to increase the overall ductility of the material. However, there are now many types of fibers with different material and geometric properties, and the exact fracture behavior of fiber reinforced concrete materials is not clearly understood. The overall aim of this paper is to establish the fracture properties and fracture behavior of concrete containing two widely used types of fibers, namely, steel (high modulus) and polypropylene (low modulus). The experimental investigation consisted of tests on cubes and notched prismatic specimens made from plain concrete and fiber concrete with 1% and 2% of steel or polypropylene fibers. The cube tests and the three point [)ending tests on notched specimens were carried Out according to RILEM specifications, and extensive data on their compressive and flexural tensile behavior and fracture energy were recorded and analyzed. The results obtained from the tests are critically assessed. and it is shown that fibers contribute immensely to the structural integrity and structural stability of concrete elements and thereby improve their durable service life.