One Dimensional Compressibility Characteristics of Clay Stabilised with Cement-Rubber Chips

Abstract

Pre-construction treatment of soft and weak deposits is necessary to ensure safety and stability of the building or infrastructure. A common treatment of such soft soils is the stabilization method, with cement and/ or lime addition to the soil to form stabilized column or platforms through mixing. This paper focuses on the 1-D compressibility characteristics of kaolin as base clay, admixed with cement as the binder and rubberchips as an additive. This approach in engineering application is also aimed at reducing the huge stockpile of the waste tyres and its potential impact on the environment. In the study, cylindrical stabilized clay specimens were prepared with various rubberchips contents and cement, and then aged for 28 days before being tested in an automated one-dimensional compressibility apparatus (i.e. Geocomp LoadTrac-II). Analysis was carried out by relating the effects of 0, 2 or 4 % cement as well as 0, 5, 10 and 15 % rubberchips addition to the base clay. The compressibility was found to decrease significantly with small quantities of cement-rubberchips addition, though the main contributor of strength came from the cement. Also, comparison of the gradient of the reloading curves for stress levels less than the preconsolidation stress and also beyond that stress is presented. The prediction of the yield stress or settlement with higher or lower cement or rubberchips content was also analyzed. Overall, the cement-rubberchips proved to effectively increase the1-D stiffness and therefore reduce the settlements.
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