Evaluation of fiber-reinforced and cement-stabilized rammed-earth composite under cyclic loading

Abstract

In this paper, the cyclic behavior of Rammed Earth (RE) elements is investigated by imposing strain-controlled cyclic loads. RE samples comprise plain soil, Waste Tire Textile Fiber (WTTF)-reinforced specimens (FR), cement-stabilized specimens (CS), and simultaneously reinforced and stabilized (CSFR) specimens. Cyclic properties and responses such as maximum stress, plastic strain, dynamic elastic modulus, damage, and plastic strain energy are evaluated. Two models are also proposed and tested against the experimental data for predicting the plastic strain and damage in different loading cycles. CT-Scan images are also provided for visual inspection of fractures and crack growth. Based on the results, plain and CS samples are found to show the weakest cyclic behavior, since they experience high maximum stress reduction, dynamic elastic modulus deterioration, damage, and plastic strain energy. Extensive and continuous cracks are also detected in these specimens according to CT-Scan images. On the other hand, CSFR specimens enjoy both high strengths induced by cement stabilization and ductility imparted as a result of fiber reinforcement. CSFR specimens with high fiber contents undergo relatively low maximum strength reduction, dynamic elastic modulus deterioration, damage, and plastic strain energy. FR specimens are also found to display relatively decent cyclic behavior. As a result, it is deduced that among the tested soil mixtures, CSFR specimens (with a WTTF content higher than 2%) have the most suitable performance under cyclic loadings.