Mechanical Performances of Green Engineered Cementitious Composites Incorporating Various Types of Sand

Abstract

This paper evaluates the mechanical performances of green engineered cementitious composites (ECC) by means of compressive strength and flexural behaviour. Green ECC made of cement, ground granulated blast-furnace slag (GGBS), river sand or recycled concrete fine (RCF), polypropylene (PP) fiber, water and superplasticizer (SP) was employed in this study. Compression test result implies that green ECC incorporating either sieved river sand or sieved RCF (below 600 μm) in series G60 and G70 exhibited greater compressive strength compared with green ECC with unsieved river sand. In series G80, compressive strength of green ECC was not affected by RCF content. Flexural stress-mid deflection curves demonstrated that all green ECC specimens performed more ductile compared to normal concrete as they undergone large deformation capacity after the first cracking strength. Both compression and flexural tests suggested that mixture G80SRCF0.4 containing large amount of sieved RCF and least amount of cement is the best green ECC mixture in this study.

Compression and Flexural Behavior of ECC Containing PVA Fiber

“…Apparently, the control specimen demonstrates brittle behavior in which the plate specimen failed directly upon reaching its first cracking strength. This behavior is similar to normal concrete, as demonstrated in a study by Lee et al (2019b). For the control specimen, neither GGBS nor PVA fibers were incorporated in the cementitious matrix, and it consisted of only cement mortar.…”

“…There are few types of fibers commonly employed in ECC mixtures, and it is found that ECCs that contain polyvinyl alcohol (PVA) fibers have consistently exhibited excellent durability, greater mechanical properties as well as enhanced structural performances (Meng et al, 2017;Pakravan et al, 2018;Yang & Li, 2014). Some researchers explored the use of polypropylene (PP) fibers instead of PVA in the making of ECC, together with some of the locally available materials (Zhang et al, 2014;Zhang et al, 2015;Lee et al, 2018b;Lee et al, 2019a, Lee et al, 2019bZhu et al, 2020). In one of these studies, PP fibers of volume fractions 1.5%, 2.0%, and 2.5% were employed in ECC with GGBS to study the flexural strength and ductility (Lee et al, 2018b).…”