Lightweight Rubberized Concrete Slabs for Sustainable Road Pavements Serving Non-Auto Traffic

Abstract

Non-auto transportation infrastructure, such as bicycle lanes and sidewalks, serves as an efficient means of public mobility. Improving the sustainable design and construction of the concrete slabs that compose such roads promotes environmental and economic benefits, spanning the usage of green sources of materials and reduced maintenance costs. In this study, an investigation into the application of recycled tires, also known as tire-derived aggregate (TDA), combined with rotary-kiln produced expanded clay (EC) as coarse aggregates in concrete, as well as their life-cycle cost assessment, are presented. The mechanical properties of concrete specimens with three different mix designs, i.e.,100% EC (MIX A or control mix), a mixture of 20% EC – 80% TDA (MIX B), and 100% TDA (MIX C) as coarse aggregates, were first derived through experimental tests. Impact-fatigue tests were then conducted on concrete slabs of MIX A, B, and C to evaluate their sustainability under several cycles of bicycle loads. The results showed that the TDA concrete has lower compressive and flexural strength, but it is more ductile than concrete with zero rubber content. Also, the results of impact-fatigue tests combined with a life-cycle cost analysis indicated the long-term benefits of constructing green and durable infrastructure using TDA on future investments in transportation.