Technical Description:
• CON/SPAN
® O-Series
® Bridge System
• Span: 48’
• Rise: 7’-6 3/4”
On August 29, 2005, high winds during Hurricane Katrina caused flooding, scouring, erosion and material loss to the canal crossings in St. Bernard Paris, Louisiana. Debris deposits accumulated throughout the waterways, contributing to excessive sediment deposits. Inspections after the flood waters receded uncovered a multitude of problems with 51 of the existing culverts. At least 10 of the structures sustained enough damage to make them eligible for full replacement using the Federal Emergency Management Agency's Hazard Mitigation Grant Program (FEMA HMGP). The HMGP provides funds to implement hazard mitigation measures following a federally declared disaster. So far, seven of the structures have been replaced, including one at Golden Drive in Chalmette.
After a thorough investigation of many different crossing options including multi-barrel pipe crossings, concrete culverts, aluminum box culverts, etc., St. Bernard Parish selected the 48' x 7'-6 3/4" CON/SPAN® O-Series® Bridge System as the best solution for a variety of reasons. Not only was it the most economical solution, but the clear span arches provided sufficient span and waterway area preventing future debris buildup and flooding. Since the buried arch design allows for existing utilities to run in the fill, they remain accessible for future maintenance as required. The fully precast arch and wall system decreased construction time, and, in many cases like this one, the entire bridge superstructure was installed in a single day. Lastly, the precast arch is aesthetically pleasing and provided the assurance of a long design life as well.
An existing elevated force main located on site created a challenge during installation of the precast units. Since it was impossible to move or even temporary relocate the main, it was imperative that the units be placed carefully without disturbing the existing pipe. Contech Engineered Solutions worked with St. Bernard Parish and the contractor, Buck Town Contractors & Co., to determine the best plan. Ultimately, the challenge was met by the adding more lift points to the precast units allowing for more flexibility while lifting the structure and setting it in place.
Contech’s partnership with St. Bernard Parish and their efforts to rebuild critical roadway infrastructure has been a diligent effort for all involved. Through this partnership, Contech has been able to assist St. Bernard Parish with efficient and economical precast bridge systems through the implementation of our CON/SPAN O-Series solutions. The series of crossings St. Bernard Parish improved through the use of HMGP funding is a shining example of how a team can work together throughout the entire process to provide a high value solution. In this application, precast concrete proved to be the best solution due to its proven versatility, quality and durability.
Technical Description:
• CON/SPAN
® O-Series
® Bridge System
• Span: 48’
• Rise: 7’-6 3/4”