Assessment of Strengths of Crumb Rubber Concrete at Low Temperature

The disposal of waste rubber has attracted a great deal attention because of the serious environmental problems caused by the growing overuse of rubber products. A feasible alternative that has caused concern is the incorporation of recycled materials into cementitious composites in civil construction. The performance of such materials at ambient temperature has been fully reported in the literature. However, limited data is available on the behaviors of crumb rubber concrete (CRC) at low temperature. This article studies the features of the cubic compressive strength, splitting tensile strength, and tension-compression ratio of CRC specimens at ambient temperature of 20°C and low temperatures of 0°C and −30°C. By experimental tests, the effects of the rubber content and water-binder ratio on the mechanical properties were analyzed. It was shown that the compressive strength and splitting tensile strength of CRC are significantly enhanced with the decrease of temperature, which is similar to the case of conventional concrete, but the trend of strength growth at low temperatures differs from the trend of strength growth at the ambient temperature of 20°C. The tension-compression ratio of CRC increases gradually with the temperature decrement, indicating that the CRC still exhibits excellent ductility at low temperature. As comparative analysis, it is known that when the water-binder ratio is 0.40, and the volume replacement rate of rubber substituted for fine aggregate is 20 %, the CRC presents optimal mechanical properties at a low temperature of −30°C. The assessment of the strengths of CRC at low temperatures may support the necessary experimental data for the application of CRC at low temperatures.