Prosperity Mining needed a railroad spurto connect their facilities to an existing line. Lochmueller Group (Lochgroup) designedfour bridges along the proposed railroad spur on a tight time frame to meetagreements made between a utility company and CSX Transportation. All fourbridges were designed, detailed, reviewed by CSX, and constructed in 10 months.
The bridges were designed for Cooper E 80 Loads and analyzedfor American Railway Engineering Association’s (AREA) Alternative Live Loading.The bridges were designed to meet AREA specifications as well as the CSXTransportation’s Criteria for Ballast Deck Railroad Bridges. Each of thebridges used adjacent special prestressed concrete box beams; the sizes of thebeams varied depending on the length of the spans. Close coordination wasrequired between Lochgroup and CSX officials.
The bridges designed included:
Conger Creek Bridge
The bridge spanning Conger Creek was a 3-span (33’; 33’;33’), prestressed concrete adjacent box beam bridge.
Harbin Creek Bridge
The bridge spanningHarbin Creek was a 2-span (60’; 60’) prestressedconcrete adjacent box beam bridge.
Robb Creek, South Y, Bridge
The bridge spanning Robb Creek on the South Y of therailroad spur was a 3-span (45’; 45’; 45’), prestressed concrete adjacent box beambridge. The railroad alignment at the location of this bridge was in a sharphorizontal curve. For ease of construction and to keep costs down, each span wasbuilt along its short chord. This provided the effects of a curved bridge withthe simplicity of a tangent bridge.
Robb Creek, North Y, Bridge
The bridge spanning Robb Creek on the North Y of therailroad spur was a 3-span, prestressed concrete adjacent box beam bridge.