Experimental Modal Analysis of Polypropylene Fiber Reinforced Concrete

Abstract

This paper experimentally investigates the static and dynamic properties of polypropylene fiber reinforced concrete (PPFRC). And also, the main objective of this present study is to examine the dynamic behavior of damaged and undamaged PPFRC beams in free-free constraints. The static properties have been carried out by conducting compression, splitting tensile and flexural strength. In addition to this, dynamic properties such as damping ratio, mode shape and fundamental frequency of PPFRC beams were also determined experimentally. In this paper, the influence of 0.1, 0.2, 0.3 and 0.4% variation of fiber contents by volume fraction of concrete with constant water-cementitious ratio of 0.31 was investigated for M50 grade of concrete. In order to determine the effect of polypropylene fibers in concrete and to compare, the properties of plain concrete have also been studied. The test results emphasize that the addition of fibers reduces the fundamental frequency and increase the damping ratio of concrete. Damping of PPFRC beams increases with the increase of damage while the fundamental natural frequency decreases with an increase of damage. The changes of fundamental natural frequency and damping values have been correlated to the damage degree of the prismatic beam experimentally.