Dynamic Compressive Strength Tests of Corroded SFRC Exposed to Drying-Wetting Cycles with a 37 mm Diameter SHPB.

Hui Chen,Qiang Li,Xin Huang,Rui He,Xiangqiang Zhou

doi:10.3390/ma14092267

Abstract

This study focuses on the dynamic compression performance of corroded steel fiber-reinforced concrete (SFRC) exposed to drying–wetting chloride cycles by a 37 mm diameter split Hopkinson pressure bar (SHPB) system. Three steel fiber contents (0.5%, 1.0%, 2.0%, by volume) were incorporated into concrete, and samples were subjected to drying–wetting cycles for different corrosion durations (30 days, 60 days, 90 days) after 28 days age. The sample damage mode, stress–strain curve and the dynamic compression performance of corroded SFRC were compared with plain concrete. Through the experimental data, strain-rate effect, fiber reinforcement effect and the corrosion duration influence on the impact compression property of SFRC were identified. The dynamic increase factor results of these samples were compared with the existing models in previous published literature. An empirical dynamic increase factor profile characterization model considering fiber content, corrosion duration and strain-rate is proposed.

Highlights

Concrete is the most widely used building material around the world due to its low cost, abundant availability of raw materials and strong compressive strength
The results showed that the compressive strength and elastic modulus exhibited increasing sensitivity to strain rate with increasing steel fiber content, and the energy absorption capacity had a strong dependency on the steel fiber volume fraction under high strain rate
To fill the aforementioned knowledge gaps, this study focuses on the dynamic compression performance of Steel fiber-reinforced concrete (SFRC) by a 37 mm diameter split Hopkinson pressure bar (SHPB) system

Summary

Introduction

Concrete is the most widely used building material around the world due to its low cost, abundant availability of raw materials and strong compressive strength. Steel fiber-reinforced concrete (SFRC) [4] has many engineering applications because of its better strength, ductility and impact loading resistance compared to ordinary concrete. Hao and Hao [8] studied the effects of steel fiber content (0–1.5% by volume) and strain rate (50–200 s−1) on the dynamic compressive behavior of SFRC. Lok and Zhao [21] studied the impact response of SFRC through an SHPB and found that the unconfined uniaxial compressive strength of SFRC increases with strain rate in the same way as for plain concrete. Strain-rate effect, fiber reinforcement effect and the corrosion duration influence on the impact compression property of SFRC were identified. Note: all aggregates were in saturated surface dry (SSD) condition

Sample Preparation

Sample Damage

Stress–Strain Curve of Tested Samples

Dynamic Increase Factor

Conclusions