Experimental Investigation on the Freeze-Thaw Resistance of Steel Fibers Reinforced Rubber Concrete.

Tao Luo,Chaowei Sun,Chi Zhang,Xiaosa Yuan,Yanjun Ji,Xinchao Zheng

doi:10.3390/ma13051260

Abstract

The reuse of rubber in concrete results in two major opposing effects: an enhancement in durability and a reduction in mechanical strength. In order to strengthen the mechanical properties of rubber concrete, steel fibers were added in this research. The compressive strength, the four-point bending strength, the mass loss rate, and the relative dynamic elastic modulus of steel fiber reinforced rubber concrete, subjected to cyclic freezing and thawing, were tested. The effects of the content of steel fibers on the freeze–thaw resistance are discussed. The microstructure damage was captured and analyzed by Industrial Computed Tomography (ICT) scanning. Results show that the addition of 2.0% steel fibers can increase the compressive strength of rubber concrete by 26.6% if there is no freeze–thaw effect, but the strengthening effect disappears when subjected to cyclic freeze–thaw. The enhancement of steel fibers on the four-point bending strength is effective under cyclic freeze–thaw. The effect of steel fibers is positive on the mass loss rate but negative on the relative dynamic elastic modulus.

Highlights

As a result of the growing number of transport vehicles, the number of waste tires keeps increasing.Due to the large amount of ground needed and the threat to the environment caused, burying is not effective for the disposal of waste tires
With the increase of freeze–thaw cycles (FTCs) from 0 to 150, the compressive strengths keep decreasing for all contents (0.0%, 1.0%, 1.5% and 2.0%) of steel fibers
In the case of no freeze–thaw cycles, the compressive strength increased with the increase in the contents of steel fibers; this means the addition of steel fibers can enhance the compressive strength of rubber concrete when there is no freeze–thaw effect

Summary

Introduction

As a result of the growing number of transport vehicles, the number of waste tires keeps increasing.Due to the large amount of ground needed and the threat to the environment caused, burying is not effective for the disposal of waste tires. The reuse of tire rubber as an additive to or replacement of construction materials has become a highly preferable option for energy saving and environmental protection [1,2]. The reuse of rubber in concrete results in two major opposing effects: an enhancement in durability and a reduction in mechanical strength [3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22]. Replacing more than 25% of fine aggregates with rubber crumb caused the compressive strength of concrete to drop significantly [5]. The addition of rubber particles into mortar reduced both the material unit weight and the thermal conductivity [7]

Objectives

Methods

Results

Conclusion