Evaluation of scour potential of cohesive soils - phase 2.

Details

• Creators:
  Anderson, J. Brian ; Fang, Xing ; Walker, Melvin E. ; Wright, William H. ; Chen, Gang
• Corporate Creators:
  Auburn University. Highway Research Center
• Corporate Contributors:
  Alabama. Dept. of Transportation
• Subject/TRT Terms:
  Bridge Foundations Cohesive Soils Depth Erosion Scour Shear Stress
• Publication/ Report Number:
  ALDOT 930-789-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Alabama
• Corporate Publisher:
  Auburn University. Highway Research Center
• Abstract:
  Determination of erosion parameters in order to predict scour depth is imperative to designing safe,
  
  economic, and efficient bridge foundations. Scour behavior of granular soils is generally understood,
  
  and design criteria have been established by the Federal Highway Administration. The same is not true
  
  for cohesive soils, and because of their complexity, a universal scour prediction method has not been
  
  established by the industry. The Erosion Function Apparatus (EFA) was created to determine the rate
  
  of scour of cohesive soils under known shear stresses, which can then be used to predict scour depths
  
  under similar conditions. During this study, ten cohesive soil formations were sampled with the
  
  assistance of the Alabama Department of Transportation. Specimens from these formations were scour
  
  tested in an updated EFA featuring an ultrasonic sensor for quantitative erosion measurements. EFA
  
  tests were performed to determine erosion functions and whether any formations demonstrated scour
  
  resistance. Geotechnical index tests were also performed on these formations to correlate scour to
  
  geotechnical properties. Results of testing verified the performance of the ultrasonic sensor and updated
  
  EFA. Three of the ten tested formations were scour resistant. Scour resistant formations has SPT N
  
  value 60 or more with moisture content less than 22% and mean grain size less than 0.008 mm. Velocity
  
  and shear stress based erosion functions were generated for the seven scourable formations with scour
  
  rates upwards of 15 mm per hour.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:dcf3401061091a1ac972854cf4aea63b0de4d3e182a8fbba68ef1915d139a1ad
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/29483/dot_29483_DS1.pdf
• File Type:
  [PDF - 4.63 MB ]