A Study of Intermediate Geomaterials and Highly Erodible Rock

Details

• Creators:
  Kulesza, Stacey E. ; Chavez, Wilson F. Espinoza ; Barman, Konica ; Castillo, Rodolfo
• Corporate Creators:
  Kansas State University Transportation Center. Department of Civil Engineering ; Texas State University--San Marcos
• Corporate Contributors:
  Texas Department of Transportation ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  • Shale
  • Erosion
  • Porosity
  • Geomaterials
  • Slopes
  • Permeability coefficient
  • Environmental protection
  • Decision making
• Publication/ Report Number:
  K-TRAN: KSU-22-8
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Kansas
• Edition:
  Final Report: July 2021 - December 2023
• Corporate Publisher:
  Kansas. Department of Transportation. Bureau of Materials and Research
• Description:
  Although substantial research on soil erodibility has recently been conducted at the federal (e.g., NCHRP 915) and state (e.g., K-TRAN: KSU-15-4; K-TRAN: KSU-18-5) levels, information regarding erosion characteristics of rock or intermediate geomaterials, such as shale, is extremely limited. Shale exposure on cut slopes or natural slopes leads to potential erosion. The objective of this research was to measure the erodibility of Kansas shales, specifically loose, weathered material collected from the surface of cut slopes and the denser, intact specimens below. Because erosion characteristics differ significantly, this study also developed a simple method to predict the time over which shale transitions from not erodible to highly erodible. Samples were collected from five sites that had exposed shale on a cut slope, and the loose material at the top of a Shelby tube was reconstituted for erosion testing and constant head testing to determine hydraulic conductivity. The dense, intact material was tested in the Shelby tube without extrusion for erosion testing and hydraulic conductivity via the falling head permeability test. Falling head tests were performed before and after exposure to controlled freeze-thaw conditions to evaluate changes in permeability and subsequent porosity under Kansas-like environmental conditions-key indicators of erosion potential in shale. An empirical model was also developed to predict the number of freeze-thaw cycles needed for non-erodible intact shales to transform into highly erodible weathered material. The Kansas Department of Transportation could use this thorough analysis to improve decision-making and effective erosion mitigation strategies in similar geological settings. Results of this study also enhance understanding of shale erosion processes, with practical implications for infrastructure safety and environmental protection.
• Format:
  PDF
• Funding:
  C2188
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/93727/dot_93727_DS1.pdf
• File Type:
  [PDF - 3.43 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:b375b8e1cf6e5c7f6dcad2e01768d290ecb2cff17588ea73d7884f9352e84155bb39a365c81c674fdb5054cfdbeb1392691d0c09da92296749b07822b7adf445