Managing Stable Waterways at Bridges in the Mid-Atlantic

Open Access
Author:
Carroll, Samuel N
Graduate Program:
Civil Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 19, 2017
Committee Members:
  • Dr. Peggy Johnson, Thesis Advisor
  • Dr. Xiaofeng Liu, Committee Member
  • Alfonso Mejia, Committee Member
Keywords:
  • stream crossings
  • stream stability
  • channel stability
  • bridge crossings
  • bridges
  • stream assessments
Abstract:
In this study, a methodology is developed for creating stable channel transitions at bridge stream intersections. A methodology is developed to assess the level of success of a channel transition project based on the project’s attainment of a multi-criteria definition of a successful transition. In addition, the methodology guides the design type selection process for new construction. For existing channel transitions, the assessment method provides an objective way of rating the ability of a channel transition project to address the complexities presented at a site. The design type selection methodology guides the designer to select a design that addresses the instabilities identified in a rapid channel stability assessment. The rapid channel stability assessment is also used to identify bridge crossings where “do nothing” is a potentially valid solution. Once a design type is selected, the designer can check for trends in potential for sediment mobilization or deposition using a velocity ratio analysis, and to identify design weaknesses through a design failure modes and effects analysis. Based on the sites included in this study this methodology aptly assesses existing transitions and provides valuable input to decision makers considering constructing transitions at existing or new bridges. Based on the sample of bridges in this study, do nothing is a potentially valid solution when the stability analysis results in a rating of excellent or good. This methodology can be applied to existing and new bridges and at locations both within and outside of the Mid-Atlantic.