Characteristics of Basalt Macro-Fiber Reinforced Recycled Aggregate Concrete

Abstract

This study aims to examine the impact of using basalt macro-fibers (BMF) on characteristics of concrete made with recycled concrete aggregates (RCA). Test variables included the initial concrete grade (normal- and high-strength concrete (NSC and HSC)), RCA replacement percentage (30 and 60%), and BMF volume fraction (νf = 0.5 to 1.5%). The compressive strength reduction in the plain concrete caused by RCA was sensitive to the RCA replacement percentage rather than the initial concrete grade. The splitting and flexural strength reductions of the plain HSC caused by RCA were more significant than those of their NSC counterparts. The use of BMF compromised the concrete workability. Such a detrimental effect increased with the BMF content and was more pronounced for the HSC with 60% RCA. Reinforcing of RCA-based concrete with BMF tended to improve the mechanical properties. In some instances, the use of BMF at νf > 1% caused a decay in the strength gain. The addition of BMF to RCA-based concrete had a potential to fully restore the original splitting and flexural strengths of plain concrete mixtures made with natural aggregates (NA). The increase in the compressive strength of the RCA-based concrete caused by BMF was, however, not sufficient to fully restore the original strength of the NA-based plain concrete. The resistances to water penetration and abrasion of the RCA-based concrete improved by up to 17% and 47%, respectively, due to the addition of BMF. Idealized tensile softening laws were established for RCA-based concrete reinforced with BMF.

Material Performance Evaluation of Cinder Based Light Weight Concrete with Micro-reinforcement

“…For analysis purpose, a database on fibre reinforced lightweight aggregate concrete has been created referring to several literature (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27) . The constituents of the lightweight concrete such as mineral admixture, cement content, fine aggregate, coarse aggregate, lightweight aggregate, water and fibre content were taken as response variables and the performance parameters which included compressive strength, flexural strength and modulus of elasticity were taken as the predictor variables.…”

Property Improvement of Recycled Coarse Aggregate by Accelerated Carbonation Treatment under Different Curing Conditions

“…However, the physical and mechanical properties of RA are lower than those of the natural aggregate (NA) due to the loose pore structures within the old mortar and old interfacial transition zone (OITZ) [14][15][16][17][18]. The aforementioned significant flaws severely limit the use of RA in practical engineering [19].…”