SLURRY WALLS SOLVE CONTAMINATION AND GROUNDWATER PROBLEMS AT A RAILROAD UNDERPASS SITE IN DENVER, COLORADO

The City of Denver, Colorado needed to replace the aging 15th Street Viaduct, a 2,400 foot-long steel roadway bridge structure. The original structure was built in the 1950s to carry traffic above a railroad freight yard. The structure was replaced with a highway underpass and a railroad bridge to carry rail traffic over the highway. Due to the urban location, a railroad detour could not be built to reroute trains during construction. Construction occurred within 20 feet of active rail lines. Possible contamination from over 100 years of mixed development at the site, shallow groundwater, and two adjacent rivers led to the selection of a slurry wall structure to isolate the underpass from contamination and groundwater. Reinforced concrete slurry walls in conjunction with cement-bentonite seepage barrier slurry walls were chosen to support the underpass excavation, cut off groundwater from the excavation, and provide abutment foundations for top-down construction of the railroad bridge. The slurry wall was constructed in three phases so the two railroad lines could remain in service. The reinforced concrete slurry walls were designed to transfer the bridge loads to the underlying bedrock through end-bearing resistance. Lateral resistance was provided by constructing slurry wall "T" panels. The underpass was designed to accommodate up to 100 gallons per minute of groundwater inflow. Measured rates have been less than 20 gallons per minute. (A) For the covering abstract see IRRD 873033.

Language

  • English

Media Info

  • Pagination: p. 541-7

Subject/Index Terms

Filing Info

  • Accession Number: 00712404
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • ISBN: 90-5410-343-4
  • Files: ITRD
  • Created Date: Oct 24 1995 12:00AM