Muthanna Journal of Engineering and Technology
Volume (12), Issue (1), Year (30 June 2024), Pages (63-71)
DOI:10.52113/3/eng/mjet/2024-12-01/63-71
Research Article By:
Othman Hameed Zinkaah, Zainab Alridha, Musab Alhawat and Amir Khan
Corresponding author E-mail: Othman.h.zinkaah@mu.edu.iq
ABSTRACT
Rubberised concrete provides elasticity, energy absorption, lightweight, and excellent acoustic and thermal insulation. Nevertheless, a notable drawback is its reduced compressive strength. To address this, incorporating silica fume emerges as a promising method to enhance compressive strength and overall performance. The current study aims at optimising the mechanical and thermal characteristics of rubberised concrete by incorporating silica fume as an additive. The investigation focuses on identifying the optimal ratio of crumb rubber and silica fume that yields favourable results across various properties, with a particular emphasis on compressive strength and thermal conductivity. Nine concrete mixes were developed, wherein 10% and 20% of the fine aggregate were substituted with two different percentages of crumb rubber. In addition, silica fume was used to substitute 10% and 15% of the cement. The experimental phase involved conducting tests for both compressive strength and thermal conductivity. The findings indicated a progressive decline in compressive strength as the crumb rubber content increased. This trend, however, was counterbalanced by the strengthening influence of silica fume. The density exhibited a decline with higher rubber content, but a marginal increase was observed upon the inclusion of silica fume. Moreover, water absorption tests indicated heightened absorption in the presence of rubber, countered using silica fume. Furthermore, as rubber content increased, thermal conductivity decreased, enhancing the insulating properties of rubberised concrete compared to plain concrete. Silica fume, while slightly diminishing thermal insulation in non-rubberized concrete, exhibited a negligible impact on the insulation qualities of rubberized concrete. Overall, the concrete mix comprising 20% rubber and 10% silica fume demonstrated the best performance in terms of both compressive strength and thermal conductivity. This research provides valuable insights into optimising the properties of rubberised concrete, offering a compelling pathway for sustainable construction practices with enhanced characteristics.
Keywords: Rubberised Concrete, Silica Fume, Compressive Strength, Thermal conductivity.