Authors' Affiliations

Noah Hickerson, ETSU, College of Arts and Sciences, Geology Department Arpita Nandi, ETSU, College of Arts and Sciences, Geology Department David Jennings, ETSU, College of Arts and Sciences, Geology Department

Location

Culp Center Ballroom

Start Date

4-25-2023 9:00 AM

End Date

4-25-2023 11:00 AM

Poster Number

115

Faculty Sponsor’s Department

Geosciences

Name of Project's Faculty Sponsor

Arpita Nandi

Classification of First Author

Undergraduate Student

Competition Type

Competitive

Type

Poster Presentation

Project's Category

Environmental Geography, Soil Sciences, Watersheds, Geophysics

Abstract or Artist's Statement

Landslides are a massive problem within the Appalachians causing large amounts of damage, and even loss of life. Urban development on the hill slope further destabilizes slope and accelerates failure. The objective of this project is to examine the slope stability condition at an urban community in eastern Tennessee and assess the relative risk in the area.

The first step included a digital survey of the area by collecting all available soil, geology, elevation, watershed, slope, drainage condition, stream, and building footprint data. This data was collected from a multitude of sources including but not limited to the United States Geological Survey (USGS), Environmental Systems Research Institute (ESRI) and Tennessee State Government resources. After this a process of field verification was required to confirm the validity of acquired digital data. This field verification process included four separate trips that aimed to access the extent of damage, slope condition, bedrock geology, and soil information. The data collected from the previous digital survey and field verification trips were used to prepare a landslide hazard prediction map using Weighted Overlay method in ArcGIS Pro software. To validate the accuracy of the hazard map, an unmanned aircraft system (UAS) drone survey will be completed in April 2023. A final Slope Stability Hazard Map will be produced for the urban community and the report will be shared with the community members.

The result indicated that both the soil and geology reports were spatially inaccurate as the entirety of urban development was constructed on Sevier Shale Formation, whereas Knox Formation appears on the map. The slope and hill shade information were correct including the identification of a road that was uncompleted that undercut a steep slope. After our first survey the maps were combined and weighted in a “Weighted Overlay map” with slope, curvature, and stream data to make a map that showed likely areas of risk. The study area contains multiple areas with high slope instability risk. These areas are steep slopes as high as 51° and weathered shale with a lack of vegetation that has been undercut by a roadway that was unfinished. Other areas of high concern with clear evidence of slope sliding are present with the movement of supportive foundation beams. Signs of cracking and sliding have been spotted within the road leading to some of the housing complexes. This information will then be compared to a UAS drone survey to create a final Slope Stability Hazard Map.

The urban community can plant vegetation, divert storm water, keep the slope dry, and reduce overburden pressure on the slopes to reduce further movement. Costly engineering structures like slope anchors, soil nails, and retaining walls are possible solutions and could help to support the steep and overburdened slopes.

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Apr 25th, 9:00 AM Apr 25th, 11:00 AM

Slope Stability Risk Assessment in Urban Development, Eastern Tennessee Hillslope

Culp Center Ballroom

Landslides are a massive problem within the Appalachians causing large amounts of damage, and even loss of life. Urban development on the hill slope further destabilizes slope and accelerates failure. The objective of this project is to examine the slope stability condition at an urban community in eastern Tennessee and assess the relative risk in the area.

The first step included a digital survey of the area by collecting all available soil, geology, elevation, watershed, slope, drainage condition, stream, and building footprint data. This data was collected from a multitude of sources including but not limited to the United States Geological Survey (USGS), Environmental Systems Research Institute (ESRI) and Tennessee State Government resources. After this a process of field verification was required to confirm the validity of acquired digital data. This field verification process included four separate trips that aimed to access the extent of damage, slope condition, bedrock geology, and soil information. The data collected from the previous digital survey and field verification trips were used to prepare a landslide hazard prediction map using Weighted Overlay method in ArcGIS Pro software. To validate the accuracy of the hazard map, an unmanned aircraft system (UAS) drone survey will be completed in April 2023. A final Slope Stability Hazard Map will be produced for the urban community and the report will be shared with the community members.

The result indicated that both the soil and geology reports were spatially inaccurate as the entirety of urban development was constructed on Sevier Shale Formation, whereas Knox Formation appears on the map. The slope and hill shade information were correct including the identification of a road that was uncompleted that undercut a steep slope. After our first survey the maps were combined and weighted in a “Weighted Overlay map” with slope, curvature, and stream data to make a map that showed likely areas of risk. The study area contains multiple areas with high slope instability risk. These areas are steep slopes as high as 51° and weathered shale with a lack of vegetation that has been undercut by a roadway that was unfinished. Other areas of high concern with clear evidence of slope sliding are present with the movement of supportive foundation beams. Signs of cracking and sliding have been spotted within the road leading to some of the housing complexes. This information will then be compared to a UAS drone survey to create a final Slope Stability Hazard Map.

The urban community can plant vegetation, divert storm water, keep the slope dry, and reduce overburden pressure on the slopes to reduce further movement. Costly engineering structures like slope anchors, soil nails, and retaining walls are possible solutions and could help to support the steep and overburdened slopes.