WHAT HAVE BEEN ACCOMPLISHED:

JMEC has been structural consultant to perform bridge condition evaluation and load rating for 3 Bridges in Diablo Creek Golf Course that are located in the Regulatory Floodway according to the FEMA Flood Map dated March 21, 2017.

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. 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.

These 3 bridges were evaluated for safety and potential code violation issues. Safety evaluations included accessibility, their current conditions, structural adequacy and safe load carrying capability. Potential Code Compliance Issues included deck width, bridge railing, and approach railing. Deficiencies of these bridges have been identified with recommended mitigation measures.

Accessibility and pedestrian safety was evaluated in accordance with 2016 California Building Code. Safe load carrying capacities of the bridges were evaluated in accordance with the 2011 Manual for Bridge Evaluation (MBE) including revisions up to 2015. Evaluation of lateral forces including seismic, wind and stream pressure, and structural design of railings and replacement components were in accordance with AASHTO LRFD Design Specifications, 2012 Sixth Edition, with Caltrans Amendments dated 2014.

These three bridges were found to have the following noncompliance features that require future improvements:
- Insufficient Bridge Clear Width for Live Load
- Lack of Approach Railings
- Damaged Bridge Railings
- Code Noncompliance Rail Spacing and Details
- Insufficient Load Carrying Capacity
- Bridge soffit is below 100-year flood high water level

Project Role:  Prime Design Consultant and Bridge Load Rating Engineer

Clients:  City of Concord

Schedule:  Completed in 2017
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Bridge #10
Bridge #13
Bridge #17