Mirafi HP-Series products allow for simultaneous construction of retaining wall and bridge
TenCate Geosynthetics North America utilized Mirafi HP-Series woven polypropylene geotextiles to reinforce the new St. Anthony Falls Bridge, which was constructed following the collapse of the I-35W Mississippi River Bridge in Minneapolis.The I-35W bridge was an eight-lane steel truss arch bridge that carried 140,000 vehicles per day across the Mississippi River in Minneapolis. The bridge catastrophically collapsed during evening rush hour on Aug. 1, 2007, killing 13 people and injuring approximately 100 more.On Sept. 18, 2008, engineers completed the new St. Anthony Falls Bridge. The 10-lane bridge has a 100-year life span and measures 189 ft wide. To expedite the design- build process, engineers used TenCate high-strength geotextiles in the project, which was completed in 339 days.In order to allow simultaneous construction of a retaining wall and the bridge, a temporary 10- to 12-ft fabric-wrapped wall was installed at four locations adjacent to the bridge abutment. Engineers chose Mirafi HP570 to provide the necessary reinforcement for the temporary retained structure and its durable face. This material is composed of high-tenacity polypropylene yarns, which are woven into a stable network, making the product inert to biological degradation and resistant to naturally encountered chemicals, alkalis and acids.