Researchers

Dr. Aref M. al-Swaidani; Prof. Dr. Tamer al-Hajeh

Published in

Journal of Engineering Science and Technology, Vol. 14, No. 4, August 2019, pp. 2320-2344

Abstract

The use of Recycled Concrete Aggregate (RCA) is limited in structural applications due to a loss of concrete strength and a reduction of its resistance against the aggressive environments" The objective of this study was to mitigate the drawbacks induced by using plain RCA, through adding limestone filler (LF) and Volcanic Scoria (VS) as cement replacement. The concrete performance was evaluated in terms of workability, mechanical and permeability-related properties. Workability was examined through the slump loss during 100 min of mixing. The investigated mechanical properties include compressive strength, splitting tensile strength and modulus of elasticity of concrete. Water permeability, chloride penetrability and porosity have particularly been studied to evaluate the concrete permeability properties. The experimental part was conducted in accordance with international standards (EN, ASTM, ISO). The results revealed that the use of LF or/and VS could improve slump loss behaviour in Recycled Aggregate Concretes (RAC). Use of such additives in RAC could also produce greater compressive and splitting strengths than those of the plain RAC. The modulus of elasticity of plain RAC was much lower than that of the natural aggregate concrete.

However, with these additives, the mechanical properties of RAC were comparable to those in natural aggregate concrete. Further, the results showed that the permeability properties of RAC have significantly been improved with the addition of both LF and VS" Dolomitic aggregates were used for comparison and SEM analysis was employed as well.

Key words: Durability, Limestone filler, Mechanical strength, Permeability, Recycled concrete aggregate, Volcanic scoria.

Link to read full paper

http://jestec.taylors.edu.my/Vol%2014%20issue%204%20August%202019/14_4_32.pdf