Predicting Critical Shear Stress of Cohesive Sediments/Soils in Riverbeds

In 2019 K-State completed a successful two-year study on creating a new equation for predicting the critical shear stress of cohesive soils around bridge abutments (KSU 18-5 / 21-01). Prior to this study, Kansas Department of Transportation (KDOT) either had to make overly conservative assumptions or send samples for erosion testing, which are costly. Critical shear stress is a soil parameter needed to estimate bridge scour and erosion countermeasures for design. KSU 18-5 / 21-01 focused on samples in the overbank (floodplain) because erosion/scour around the abutments was a priority to KDOT, difficult to predict, and because sampling in the overbanks was a priority in developing the shear stress prediction equation. However, now that KDOT has a new critical shear stress equation, it should be validated for sediments in the riverbeds. Alternatively, another design equation may be required for riverbed sediments. The bridge scour estimating methods in HEC-18 include different design equations for abutment, contraction, and pier scour so it would not be unreasonable to have a different equation for riverbed sediments.


    • English


    • Status: Active
    • Funding: $52536
    • Contract Numbers:

      K-TRAN: KSU-22-4



    • Sponsor Organizations:

      Kansas Department of Transportation

      Eisenhower State Office Building
      700 SW Harrison Street
      Topeka, KS  United States  66603-3754
    • Performing Organizations:

      Kansas State University Transportation Center

      Kansas State University
      Department of Civil Engineering
      Manhattan, KS  United States  66506
    • Principal Investigators:

      Hutchinson, Stacy

    • Start Date: 20210701
    • Expected Completion Date: 20240731
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01832306
    • Record Type: Research project
    • Source Agency: Kansas Department of Transportation
    • Contract Numbers: K-TRAN: KSU-22-4, RE-0838-01, C2186
    • Files: RIP, STATEDOT
    • Created Date: Jan 7 2022 12:17PM