Presentation on theme: "Presentors: Tom Hardinger – Wisconsin DOT Eugene Hietpas – Collins Engineers Inc. This presentation and its contents may not be duplicated or reproduced."— Presentation transcript:
Presentors: Tom Hardinger – Wisconsin DOT Eugene Hietpas – Collins Engineers Inc. This presentation and its contents may not be duplicated or reproduced without the expressed written consent of Collins Engineers, Inc.
NC Region Various Structures – Structures B-37-0187, B-71-0018, B-49-0090 Background Information Design Phase Construction Phase As-Builts
Background Information Project included 3 bridges over Wisconsin River (Marathon, Portage and Wood Counties in central Wisconsin). Substructure units are conventional seal, footing and pier walls. Major flood events 2008, 2010 and 2011. Post-flood dive inspections revealed major scour issues with streambed and/or substructure undermining. Project initiated in 2011 and built in late 2012.
B-37-187, STH 34, Knowlton Built 1969. Multi-span steel girder spans. 20-38 water depth. 8-10 streambed degradation during 2008 flood exposed seal-to-rock interface. Mitigated piers 2 and 3.
B-49-90, CTH HH, Stevens Point Built 1999. Multi-span pre- stressed girder spans. 8-15 water depth. Pier 4 Seal undermining at upstream nose.
B-71-18, STH 73, Nekoosa Built 1962. Multi-span steel girder spans. 15-22 water depth. Localized scour at piers 2 thru 6.
Design Considerations Permanent vs. Temporary Repairs. Alternatives. Conventional Riprap placement. Articulated grout mats/grout bags and structural grout. Traffic disruptions. Environmental. Project Inspection - Most work underwater.
Design Challenges Limited WDOT history/experience (design and construction). HEC 23 guidelines. Input from other states: Montana, Iowa, MN. Input from industry. Environmental. Aquatic bed impacts. Development of Specifications.