The utilization of waste rubber tire powder to improve the mechanical properties of cement-clay composites

Abstract

Abstract This study investigated utilizing waste tire powder as a cement replacement material in soil–cement blends. It also proposed improving cemented clays strength and stiffness characteristics to decrease environmental impacts due to cement production and waste tire dumping. A light compaction method has been utilized to produce the samples of two densities (1600\xa0kg/m3 and 1800\xa0kg/m3), three cement dosages (7%, 10%, 13%), and five tire powder contents (2.5%, 5%, 10% and 20% weight of cement) cured for 7, 28, and 60\xa0days. Mechanical properties of prepared blends have been assessed by unconfined compressive strength and ultrasonic pulse velocity tests to determine the unconfined compressive strength, elastic modulus, and initial shear modulus of samples. The results showed that 2.5% tire powder can be utilized as an optimum value. To additionally clarify the featured mechanical properties of the blends, microstructure analysis of the samples has been performed with the XRF, XRD, and SEM. Correlations have been proposed to determine unconfined compressive strength (qu), initial shear modulus (G0), and modulus of elasticity (E) to be acquired utilizing just a single test. Moreover, a novel correlation has been developed to predict the unconfined compressive strength and elastic modulus of any specimen through non-destructive testing. The final composites can be utilized in different structural and non-load bearing applications, such as a base, sub-base, embankments, rammed earth, and retaining walls dependent on the performance of the final composites.