Improvement of Geotechnical Properties of Soil using Calcium Carbide, Waste Foundry Sand and Polypropylene Fibre

This paper discusses the applications of industrial waste like waste foundry sand (۱۰%, ۲۰%, ۳۰%, and ۴۰%) and calcium carbide residue (۳%, ۶%, ۹%, and ۱۲%) blended with polypropylene fibre (۰.۲۵%, ۰.۵۰%, ۰.۷۵%, and ۱%) for soil stabilization. The purpose of this study is to develop a composite of clayey soil mixed with different additives, so it can be used for improving the geotechnical properties of the clayey soil. Multiple tests are conducted including differential free swell, Atterberg's limits test, compaction tests, unconfined compression test (UCS), and California-bearing ratio test (CBR) on clay soil individually and in different combinations and proportions with additive mixed with each other. The optimum percentage for the additives is found by performing differential free swell index and Atterberg limits test. The results demonstrate that the inclusion of additives in the clayey soil decreases the differential free swell and plasticity index of the composite but raises the composite UCS and CBR values. The maximum increase in the UCS and CBR values is obtained for optimum combination of C:PP:WFS:CC::۷۶.۲۵:۰.۷۵:۲۰:۳. Based on the CBR values, the thickness of flexible pavement is designed using the IITPAVE software. The results of the software analysis show a reduction in the pavement thickness for various values of commercial vehicles per day (۱۰۰۰, ۲۰۰۰, and ۵۰۰۰) for all combinations. The maximum reduction in layer thickness and construction costs is noticed for C:PP:WFS:CC:۷۶.۲۵:۰.۷۵:۲۰:۳. To further examine the improvement in the geotechnical properties of soil, calcium carbide residue, and waste foundry sand can be blended with nano-additives for potential uses.

کلیدواژه ها:

Compaction ، consistency limits ، california bearing ratio ، Unconfined compressive strength ، pavement design