Emergency Pier Repairs to the Liberty Memorial Bridge, Bismarck, North Dakota

摘要

This project consisted of emergency repairs made to the river piers of the Liberty Memorial Bridge over the Missouri River in Bismarck and Mandan, North Dakota. The river piers support the three 476-foot long main span truss superstructures of the bridge. In 2000, an in-depth inspection of the four piers was done to determine the extent of deterioration noted during a recent fracture critical inspection of the structure. The overall condition of the piers was found to be serious due to wide transverse cracks, extensive spalling and inoperative expansion bearings. Temporary restraining collars were installed and the bearings cleaned and lubricated. A follow up inspection in 2006 revealed increased deterioration and required closure of the structure. Using a design-build concept, steel containment jackets were designed, constructed and the bridge re-opened to traffic within 7 weeks.