Assessment of Jahn permeable mortar system in a historic bridge abutment application.

Details

• Creators:
  Colgrove III, George W.
• Corporate Creators:
  Vermont. Agency of Transportation. Research and Development Section
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  Bridge Abutments Covered Bridges Grout Historic Preservation Mortar Permeability Rehabilitation (Maintenance)
• Publication/ Report Number:
  2015-10
• Resource Type:
  Tech Report
• Geographical Coverage:
  Vermont
• Corporate Publisher:
  Vermont. Agency of Transportation. Research and Development Section
• Abstract:
  Increasingly, the importance of historic preservation is competing with the requirements to enhance
  
  structural capacity of older unique structures. Preservation of the functional and aesthetic qualities limits
  
  potential change to meet the expanded needs of the traveling public. The Taftsville Covered Bridge in
  
  Woodstock, Vermont was deteriorating at a time the public needed increased capacity. Then in 2011, the
  
  tropical storm remnant of Hurricane Irene rendered the bridge impassable. Significant damage to the
  
  substructure and superstructure occurred. The bridge required a complete deconstruction and
  
  reconstruction to correct deficiencies and enhance capacity. Design and construction techniques focused on
  
  retention of the historic presence and value the bridge offered for over a century and a half.
  
  The Taftsville Covered Bridge has been repaired and improved many times over its life. This project
  
  continued that trend by restoring one abutment and pier with added strength by the use of Jahn mortar and
  
  grout. The existing laid-up stone was repointed with Mortar with minimal addition of new stone where large
  
  gaps were located. Once the shell formed by the existing stone and the new mortar set up, a flowable grout
  
  was placed within the stones to bond the stones together, thereby strengthening the substructures. The
  
  containment of the stones provided increased reliability in addition to strength. The feature the Agency
  
  hoped to maintain was the high permeability of the abutment. The permeability of the Jahn system
  
  minimizes damage caused by internal hydrostatic pressures and the effects of chlorides locked within the
  
  stone substructures observed in other mortars and grout systems.
  
  
• Format:
  PDF
• Funding:
  2011-R-05
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:04f0f66abbf777bf259f72da43f7d57c88afe8aee47ba63e5d08a96d3ffa27e3
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/29001/dot_29001_DS1.pdf
• File Type:
  [PDF - 2.89 MB ]