Identification of Techniques to Meet pH Standard During In-Stream Construction

Many of Maryland’s tributaries traverse highway infrastructure via culverts that are managed and maintained by Maryland State Highway Administration (SHA). These culverts are often made of galvanized steel and over time are subjected to scour. Concrete grout is often used as a repair material when these issues are identified. However, once water is allowed to inundate the freshly paved culvert, the grout surface can produce a dissolution effect in which elevated pH can impact downstream waters. The occurrence of this pH spike from grout has been reported in past projects, and has resulted in concerns as the pH of water may reach above the regulatory limit of 8.5. The goal of this project was to ensure that SHA has a proper specification and remedial actions for addressing the pH concern. The overall objectives of this research were to (1) review the current specification for using grout for culvert maintenance, (2) determine the various parameters that control pH spikes for effluent waters, (3) determine applicable remedial applications, and (4) revise the current specification and provide a guidance document/tool for SHA and contractors. Laboratory and field studies were used to investigate and test these objectives.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 99p

Subject/Index Terms

Filing Info

  • Accession Number: 01520480
  • Record Type: Publication
  • Report/Paper Numbers: MD-14-SP109B4D
  • Contract Numbers: SP109B4D
  • Files: UTC, NTL, TRIS, RITA, ATRI, USDOT, STATEDOT
  • Created Date: Mar 26 2014 2:36PM