Experimental Study of the Correlation between Resilient modulus and Uniaxial Compressive Strength in Chemical and Biological Stabilization of Clay Subgrade Soil

Articles in Press

Document Type : Original Article

Authors

• Siamak Shafaghatian ¹
• Gholam Moradi ²

¹ Department of Civil engineering, Khodabandeh Branch, Islamic Azad University, Khodabandeh, Iran

² Faculty of Civil engineering, University of Tabriz , Tabriz, Iran

10.22067/jfcei.2024.83919.1248

Abstract

Due to the high cost and time-consuming nature of testing, it is useful and common to use valid correlation relationships with common soil parameters to determine the resilient modulus (MR) for design purposes. However, the validity of these relationships for stabilized soils has been less investigated. Stabilization of weak subgrade soil is a method of avoiding weak soil replacement costly and time-consuming problems. According to the Kyoto Protocol, a lot of research has been done on novel materials such as polymers and new methods like biological stabilization. This study aimed to investigate the effect of chemical and biological stabilization of clay subgrade soil on the resilient modulus and uniaxial compressive strength (qu) and accuracy of the Thompson model for correlation between these two parameters. For chemical stabilization, a solid polymer called Nicoflok and for biological stabilization, a biopolymer solution called Beta-glucan were employed. In both methods, the dry unit weight of the soil decreased and its optimum water content and qu increased. Despite similar results in the uniaxial test, the solid polymer increased the MR of the stabilized soil more than the biopolymer. Based on the regression analysis of tests data, the Thompson model had more accurate results in the Nicoflock stabilized soil than the biopolymer ones.

Keywords

• Resilient modulus (MR)
• The Thompson model
• Chemical and biological stabilization of clay subgrade soil
• Nicoflock
• Betaglucan

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