Assessment of karst activity at highway construction sites using the electrical resistivity method (Greene and Jefferson Counties, Missouri).

Details

• Creators:
  Anderson, Neil L. ; Apel, Derek B. ; Ismail, Ahmed
• Corporate Creators:
  Missouri. Department of Transportation
• Corporate Contributors:
  United States. Department of Transportation. University Transportation Centers (UTC) Program ; United States. Department of Transportation. Research and Special Programs Administration
• Subject/TRT Terms:
  Karst Karst--Missouri Pavements Pavements--Missouri--Testing Resistivity Method
• Publication/ Report Number:
  OR 07-003
• Resource Type:
  Tech Report
• Geographical Coverage:
  Missouri
• Edition:
  Final report.
• Corporate Publisher:
  University of Missouri--Rolla. Center for Infrastructure Engineering Studies
• Abstract:
  Two-dimensional (2-D) electrical resistivity data were acquired across and in proximity to active sinkholes at two Missouri
  
  Department of Transportation (MoDOT) highway-construction sites. Construction site #1 is located in Greene County, Missouri;
  
  site #2 is located in Jefferson County, Missouri.
  
  Two relatively dense grids (“1A” and “1B”) of electrical resistivity data were acquired at Greene County site #1 as part of a
  
  geotechnical investigation of a proposed interchange. Several active sinkholes with exposed throat diameters on the order of 1.5 ft
  
  had been discovered during a routine visual inspection of the site, and the District Geologist decided that a geophysical
  
  investigation was warranted prior to routine boring. The primary objective of the electrical resistivity study was to determine if
  
  substantive air-filled karstic cavities were present in the subsurface. Secondary objectives were to estimate depth to bedrock and
  
  identify anomalous subsurface conditions that might compromise the integrity of the proposed intersection or complicate
  
  construction. The electrical resistivity data proved to be of significant utility. Substantive air-filled voids were not imaged on the
  
  resistivity profiles. A depth to bedrock structure contour map was generated for the site, and prominent clay-filled and apparently
  
  inactive karstic cavities were identified beneath segments of proposed new roadway.
  
  A relatively dense grid of electrical resistivity data was also acquired at Jefferson County site #2. These electrical resistivity data
  
  were acquired because a previously unmapped, oval-shaped, clay-filled, sinkhole (approximately 50 ft x 35 ft x 15 ft; length x
  
  width x height) near the centerline of the northbound lanes effectively “emptied” overnight after overlying soil had been stripped
  
  by earth moving equipment. The supervising geologist authorized the acquisition of the geophysical data in order to image the
  
  subsurface immediately beneath and adjacent to the sinkhole. The primary concern was that the sinkhole was underlain by a large
  
  air-filled cavity. The interpretation of the resistivity data indicated the reactivated sinkhole was not underlain by a substantive
  
  cavity. Rather, the soil in the sinkhole appears to have “flowed” into the subsurface through solution-widened system of joints
  
  that do not underlie the sinkhole and probably do not pose a significant risk in terms of catastrophic collapse under load.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:f62cce9ba6499d5ca83e9e1dafe49ac4a341d8e2b1231453414b4a073f7a325a
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17417/dot_17417_DS1.pdf
• File Type:
  [PDF - 1.09 MB ]