Session: Rising Stars of Mechanical Engineering Celebration & Showcase

Paper Number: 148554

148554 - Climate Resilient Proactive Landslide Repair 

In the United States during the past 50 years global warming has initiated significant changes in precipitation and evaporation. Summers are getting warmer causing extreme drought and there are more frequent extremely heavy precipitation events that affect soil moisture and change the behavior of expansive soil. In addition, the rainfall pattern has shifted and increased in volume making Mississippi one of the top three states with the highest rainfall in the United States. Due to these changes in precipitation, the soil moisture balance is changing, which also impacts the behavior of expansive clay. The shallow slope failure is recurring in the expansive soil, which is highly plastic in nature and covers around 25% of the land area of the United States. Due to the climate change, the rainfall pattern has changed in Mississippi, which influence the behavior of expansive soil and formation of the landslides. The Vetiver grassroots has a high tensile strength, which extends up to 10 to 12 ft. depth and can be an excellent and cost-effective bio-engineered solution to repair shallow slope failure on the expansive soil. As a climate adaptive solution, vetiver grass has been tested in a Test Levee Slope in Vicksburg, MS and multiple highway slopes in Mississippi. All the slopes were stabilized using Vetiver grass and then monitored to check the growth, seasonal variation, moisture and temperature effect and seepage. Vetiver as a solution has been investigated as a Evapotranspiration based solution to counter balance the infiltration, enhance the matric suction and to increase the factor of safety of the slope. The moisture behavior of the slopes are investigated using Electrical Resistivity Imaging. In addition, 2D Finite Element Analysis was conducted in Plaxis, considering the coupled hydro-mechanical model and safety analysis. The 2D FEM analysis was validated based on the field monitoring results. The 2D FEM analysis was conducted to understand the infiltration behavior with different rainfall intensity and duration in a highway slope. In addition, the consideration of the infiltration and evapotranspiration with Vetiver grass within the same slope has been evaluated. Based on the analysis, it is evident that a fully grown vetiver grass can reinforce the slope, counterbalance the inflitration and restrict the creeping movement. In addition, due to the evapotranspiration, the matric suction of the slope goes up, which enhance the safety of the slope. Planting vetiver grass in  the highway embankments will tackle the problem by increasing the shear strength of the soil with its high strength roots and will enhance the stability of the embankment.

Presenting Author: Sadik Khan Jackson State University

Presenting Author Biography: Dr. Sadik Khan is an Associate professor in the department of Civil and Environmental Engineering at Jackson State University. He is an expert of Climate Resilient Geo-Infrastructures and worked 15+ years on innovative projects on the investigation, monitoring and evaluation of foundations, slopes and earth retaining systems. He leads and co-lead multiple projects funded by Federal and State Agencies such as National Science Foundation (NSF), Gulf Research Program, US Department of Transportation, US Army Corps of Engineers, Federal Railroad Administration and Mississippi Department of Transportation on various aspects of sustainable, resilient and smart Geo-Infrastructure. He coauthored two technical books and 100+ peer-reviewed journal and conference proceedings on different aspects of geo-infrastructure. He is an awardee of NSF CAREER and Principal Investigator of AASHTO SWEET 16 Award. He received the 2018 Engineer of the Year award from MS ASCE Section, and 2019 Engineer of the Year award from ASCE Region 5. He is an Associate Editor of ASCE Natural Hazard Review Journal. He is a technical member of TRB AKG-20 and TRB AKG-40 of National Academy, USSD Foundation Committee, USSD Levee Committee, ASCE GI Unsaturated Soil, and DFI Shallow Foundations committee. He is serving as a Vice Chair of ASCE GI Shallow Foundation committee. He is a licensed engineer in the State of Texas and the State of Mississippi.

Authors:

Sadik Khan Jackson State University
Amber Spears Jackson State University
Fariha Rahman Jackson State University
Avipriyo Chakraborty Jackson State University