Assessment of Strengths of Crumb Rubber Concrete at Low Temperature

Abstract

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.

An Analytical Mini-Review on the Compression Strength of Rubberized Concrete as a Function of the Amount of Recycled Tires Crumb Rubber

“…The same issue happens at all percentages of rubber substitution. For instance, at 30% declared substitution, the series 20A [63] or 24A [67] seem more performing than the series 18A [61], even if the latter has a much lower strength reduction with respect to the control concrete.…”

“…Thus, both the x-axis and the y-axis do not present comparable data. Considering the compression strength, it is evident in Figure 1 that, for instance, the values at 10% rubber substitution that are in the 50-70 MPa range (series 15A, 20A, 22A, 24A [59,63,65,67]) are Considering the compression strength, it is evident in Figure 1 that, for instance, the values at 10% rubber substitution that are in the 50-70 MPa range (series 15A, 20A, 22A, 24A [59,63,65,67]) are very high mostly due to the use of high-strength concrete. Other series, for instance 7A and 7B [50], have a much lower reduction in strength, but since their reference concrete has a lower strength, they seem less performing with strength values in the 20-35 MPa range.…”

“…However, it is worth noting that, based on data analysis, the chemical treatment of rubber with chemical agents (e.g., NaOH) has almost no tangible effects on the mechanical performance of the cement composite even when using high-performance cement [24,48,62,66]. (iv) Lastly, using a high-performance cement as matrix can significantly reduce the loss of mechanical properties for high substitution degree of the mineral aggregate fraction [24,37,[57][58][59]62,63,65,67].…”