Use of Crumb Rubber to Improve Thermal Efficiency of Cement-Based Materials

Abstract

Motivated by the tremendous trend toward green environment and to reduce the effect of scrap tires on the environment and human health, this research is an attempt to find a practical and environmentally sound solution of the problem of scrap tires by developing a light weight with low thermal conductivity composite construction materials using waste tires. A few literatures may be found about the effect of crumb rubber on thermal conductivity of mortar. Thus, in this research project, an experimental program was established to investigate the effect of the amount and size of crumb rubber (rubber obtained from recycling scrap tires) on the thermal properties of mortar. Four levels of crumb rubber addition: 10, 20, 30 and 40% and three sizes of crumb rubber (#30, #10_20 and a combination of both sizes) were considered to make twelve different mixtures of the rubberized mortar. Specially designed and constructed heat transfer measurement device was used to measure thermal conductivity of the specimens. Results were used to determine the optimal amount of crumb rubber that gives the least thermal conductivity, which directly related to the improvement in thermal resistance of concrete mixtures. It was found that the size and the amount of crumb rubber had an effect on thermal properties of the specimens investigated. The thermal conductivity of rubberized mortar was decreased by 28% when crumb rubber #10_20 was used. It was also found that #10_20 crumb rubber had more effect on the thermal conductivity reduction than #30 crumb rubbers. An empirical equation is proposed to predict thermal conductivity of rubberized mortar.

Ground Tire Rubber Filled Flexible Polyurethane Foam—Effect of Waste Rubber Treatment on Composite Performance

“…For analyzed materials, the value of λ coefficient attributed to solids is affected by the introduction of GTR into the polyurethane matrix. Depending on the literature reports, the λ value of shredded tire rubber varies between 0.100 and 0.166 W/(m·K) [ 59 , 60 ]. For the nonporous polyurethane, thermal conductivity coefficient is in the range of 0.200–0.260 W/(m·K), depending on the applied formulation [ 61 , 62 ].…”

Recent Trends and Challenges of Energy Efficient and Sustainable Buildings

“…Experiments discussed in (Fadiel et al, 2014), in this sense, show that a 40% content of crumb rubberalthough depending on the size of rubber particles-could offer optimized thermal conductivity (up to 28% reduction, compared to conventional mortar) for a rubberized cement mortar. It is thus expected that inclusion of crumb rubber in cement mortar could markedly improve the energy efficiency of whole structural systems.…”

“…Improved energy demand can be achieved also by means of the use of energy saving materials. Research investigations presented by Fadiel et al (2014), for example, emphasized that improved thermal efficiency of cement-based materials can be obtained by use of crumb rubber. During the last two decades, the use of rubber particles in addition to cement paste represented a research topic of large interest for scientists and industries and several States (e.g., the Arizona Department of Transportation (Kaloush et al, 2005) sustained the extended engineering reuse of waste tires in the form of crumb rubber aggregates in Portland cement concrete mixes.…”

Sound-Absorbing and Thermal-Insulating Properties of Cement Composite Based on Recycled Rubber from Waste Tires

“…Furthermore, the results of thermal properties of the prepared composites based on recycled rubber show that mixture Z2, with 100% replacement of aggregate with recycled rubber of fractions 0/1 and 1/3 in the ratio of 50:50, have better thermal conductivity result than mixture Z3 with the ratio of recycled rubber fractions of 40:60. This improvement of 11.4% is influenced by a larger share of the finer fraction of recycled rubber, which has positive effect on thermal conductivity [54,55].…”