The Influence of the Hybridization of Steel and Polyolefin Fiber on the Mechanical Properties of Base Concrete Designed for Marine Shotcreting Purposes

Chang Joon Lee,Hyunwook Kim,Chul-Woo Chung,Andres Salas Montoya,Hoon Moon

doi:10.3390/app11209456

Abstract

The present study investigated the influence of the hybridization of steel and polyolefin fiber on the mechanical performance and chloride ion penetration of base concrete designed for marine shotcreting purposes. The purpose of fiber hybridization is to reduce the risk of corrosion that might occur during service life. Sets of hybrid fiber reinforced base concrete, whose water to binder ratio was 0.338, were prepared. The fiber contents in the base concrete were 0.54 and 1.08 vol%, and the volume proportion of polyolefin fiber in the hybrid fiber varied from 0 to 100%. Although the effect of fiber hybridization was not clearly observed from the compressive strength, a synergetic effect which increased both the flexural strength and toughness occurred at a fiber content of 1.08 vol%. The optimum ratio of steel and polyolefin fiber was 50:50. With respect to chloride ion penetration, an increasing amount of steel fiber increased the amount of current passing through the base concrete specimen due to the presence of electrically conductive steel fiber. However, chloride ion diffusivity was not greatly affected by the presence of steel fiber.

Highlights

Concrete is a non-homogenous and brittle material, vulnerable to tensile forces and stresses, especially at high strength [1,2]
(1) No synergetic effect from fiber hybridization was observed for compressive strength
(2) At a fiber content of 0.54 vol%, the increasing amount of polyolefin fiber generally led to a decrease in flexural strength

Summary

Introduction

Concrete is a non-homogenous and brittle material, vulnerable to tensile forces and stresses, especially at high strength [1,2]. Polymeric fibers have been used as an alternative to steel fibers because of a relatively low cost and better construction behavior, having some useful properties such as deformability and corrosion resistance [5,9]. Due to their weaker mechanical properties than those of steel fibers, polymeric fibers do not provide higher mechanical performance than steel fibers when incorporated into concrete for reinforcement [10]

Methods

Results

Conclusion