Strength, Drying Shrinkage, and Carbonation Characteristic of Amorphous Metallic Fiber-Reinforced Mortar with Artificial Lightweight Aggregate.

Se-Jin Choi,Sung-Ho Bae,Ji-Hwan Kim,Tae-Gue Oh

doi:10.3390/ma13194451

Abstract

This paper investigates the strength, drying shrinkage, and carbonation characteristic of amorphous metallic fiber-reinforced mortar with natural and artificial lightweight aggregates. The use of artificial lightweight aggregates has the advantage of reducing the unit weight of the mortar or concrete, but there is a concern that mechanical properties of concrete such as compressive strength and tensile strength may deteriorate due to the porous properties of lightweight aggregates. In order to improve the mechanical properties of lightweight aggregate mortar, we added 0, 10, 20, and 30 kg/m3 of amorphous metallic fibers to the samples with lightweight aggregate; the same amount of fiber was applied to the samples with natural aggregate for comparison. According to this investigation, the flow of mortar decreased as the amount of amorphous metallic fiber increased, regardless of the aggregate type. The compressive strength of lightweight aggregate mortar with 10 kg/m3 amorphous metallic fiber was similar to that of the LAF0 sample without amorphous metallic fiber after 14 days. In addition, the flexural strength of the samples increased as the amount of amorphous metallic fiber increased. The highest 28-d flexural strength was obtained as approximately 9.28 MPa in the LAF3 sample, which contained 30 kg/m3 amorphous metallic fiber. The drying shrinkage of the samples with amorphous metallic fiber was smaller than that of the sample without amorphous metallic fiber.

Highlights

Concrete exerts strong performance against compression, but its tensile strength is very weak—about 8% to 12% of compressive strength—and there is increasing interest in steel-fiber-reinforced concrete to improve such properties as low flexural strength and impact strength [1]
Amorphous metallic fiber has the advantage of reducing CO2 and energy consumption in the manufacturing process because this process is simpler than that using normal steel fibers, and there is no subsequent process after the molten iron [4]
In order to reduce the weight of ultra-high-rise and large-scale concrete structures, interest in artificial lightweight aggregates having a lighter weight than general aggregates is increasing [6]

Summary

Introduction

Concrete exerts strong performance against compression, but its tensile strength is very weak—about 8% to 12% of compressive strength—and there is increasing interest in steel-fiber-reinforced concrete to improve such properties as low flexural strength and impact strength [1]. Studies of concrete with thin-shaped amorphous metallic fibers have been actively conducted [2,3,4]. Amorphous metallic fiber has the advantage of reducing CO2 and energy consumption in the manufacturing process because this process is simpler than that using normal steel fibers, and there is no subsequent process after the molten iron [4]. In order to reduce the weight of ultra-high-rise and large-scale concrete structures, interest in artificial lightweight aggregates having a lighter weight than general aggregates is increasing [6]. The use of artificial lightweight aggregates has the advantage of reducing the unit

Methods

Discussion

Conclusion