Strength and durability assessment of shredded tire rubber stabilized artificially cemented alluvial clay

Abstract

Waste usage in soil stabilization is attracting considerable interest due to its engineering, environmental, economic, and social benefits. In this context, this study investigates the performance of waste rubber tire inclusion in alluvial clay stabilized with ordinary Portland cement. For this purpose, samples of various mixes were prepared, containing soil, cement content (7%, 10%, and 13%) of the dry mass of the soil, and two types of rubber tires (i.e., powder [TRP] and fiber [TRF]) proportioned as (0%, 2.5%, 5%, 10%, and 20%) of the cement quantity. The blends were compacted at (1600 and 1800 kg/m3) dry densities and 28 and 60 days of curing. Strength and strain energy were evaluated through unconfined compressive strength tests, where the durability performance was assessed through wetting and drying cycles. Moreover, ultra-pulse velocity (UPV) as a nondestructive test was performed on the samples during their wet/dry cycles to investigate the maximum initial shear modulus (Go) change throughout the cycles. Overall, the results showed that the inclusion of 2.5% to 5% TRF or TRP replacing cement is the ideal range of rubber tire content in the composites studied concerning strength and weathering resistant performance. Furthermore, excellent correlations were obtained between the accumulative loss of mass (ALM) after 12 wet/dry cycles and the maximum initial shear modulus (Go) measured after different numbers of cycles. The porosity/binder index was also used to evaluate the ALM of the blends considering the variables of each combination, and the resulted correlations were further normalized to be aligned with various functions. This study provides an efficient approach to predict the ALM of different blends containing similar soil type, cement, and tire rubber following the proposed equations with simple experimental testing.