Stabilization of soft soil with fly-ash to improve slope stability characteristics of the soil-fly-ash mixes

Project Description

The use of soft soils for roadway and construction purposes is highly problematic. Soft soils generally lack sufficient shear strength to resist loading and can result in catastrophic failure specially on the steep slopes. Soils typically need at least 35% sand and gravel content to be considered well-graded and to produce stable strength characteristics. Soils that have a high degree of silt and organic matter also have poor erosion resistance.  Recent research shows that soil can be stabilized with fly-ash (FA), sewage sludge ash (SSA), and/or other additives and used for roadway and construction purposes that could be less problematic and stronger. This study aims to explore the soil-FA and soil-SSA mixtures ratio that would provide higher strength  and improve other engineering properties and the mixtures can be used for embankment construction with steeper slopes. The soil-FA and soil-SSA mixtures mixed with 5%, 10%, 20%, 30%, 40% FA and SSA contents will be evaluated for shear strengths, Atterberg Limits, and angle of friction. This data will be input to a slope stability program (PCSTABL or GEOSLPOE) and stability factor for safety (for seismic and non-seismic conditions) will be estimated. Based on the stability factor of safety, a soil-FA mixture or a range of soil-FA mixtures can be recommended for different uses.   

Research Requirements

Required GPA to qualify for CE 4400. However, students can work on the project without course credit. Junior or senior with GPA of 3.0 (lower GPA can be accepted with waiver) will qualify for CE 4400.

Duration

08/12/2024-05/15/2025

Contact

Dr. M.A.Karim, mkarim4@kennesaw.edu
Dr. Adam Kaplan, akaplan8@kennesaw.edu
Dr. Youngguk Seo, yseo2@kennesaw.edu