WHAT HAVE BEEN ACCOMPLISHED:
JMEC has been structural consultant to evaluate the feasibility of replacing 3 bridges. Evaluation parameters included bridge alternatives, cost for design, additional geotechnical investigations and hydraulic analyses, construction or capital cost, and construction administration including design and construction and environmental studies and permitting.
The 3 bridges were constructed of various types of steel railroad flatcars (RRFC's) with span lengths ranging from 40-feet to 52-feet with clear width less than 9-feet. They are located in the Regulatory Floodway according to the FEMA Flood Map dated March 21, 2017. Two of the bridges (Bridge #13 and Bridge #17) have timber decks with AC wearing surface and another bridge has corrugated metal deck with concrete topping (Bridge #10). All three bridges have metal pipe railings. Substructures are of concrete abutments on concrete piers. These bridges carry golf carts and maintenance vehicles over the creek. Bridge #17 is also used by heavier vehicles including H-10 trucks and fire trucks.
The replacement bridge alternatives included the use of Keystone Steel Truss, Connector Steel Truss and Pretensioned Concrete Slab Bridge. The recommended improvements included the following features:
- Increase Bridge Clear Width for live loads
- Add Approach Railings
- Add Bridge Railings per CBC and AASHTO
- Increase Load Carrying Capacity
- Raise bridge soffit above 100-year flood level
- Lengthen bridge to outside USACE jurisdiction
- Modify bridge approach to match raised profile