Bridge Type
Main Span(s): Steel [3] Truss - Thru [10]
Approach Span(s): Other [00]
Deck: Wood or Timber [8] with Wearing Surface: Wood or Timber [7]
Bridge Dimensions
Length: 23.2 m = 76.1 ft
Main Spans: 1 at 23.2 m = 76.1 ft
Approach Spans: 0
Skew: 0
Width, Roadway: 4.9 m = 16.1 ft (1 Lanes) and Out-To-Out: 5.5 m = 18.0 ft for a 5.5 m = 18.0 ft approaching roadway.
Vertical Clearance: 99.99 m = 328.1 ft and Navigational Clearance: 0 = N/A
Location
Unknown [00000]: Gallatin County [031], Montana [30]
Owned by U.S. Forest Service [64], DOT District: 0
DURNAM BRIDGE
Condition
Deck: Very Good [8]
Superstructure: Satisfactory [6]
Substructure: Good [7]
Loading
Design:
Operating: 13.3 metric ton = 14.6 tons (Load and Resistance Factor Rating (LRFR) rating reported by rating factor (RF) method using HL-93 loadings [8])
Inventory: 10 metric ton = 11.0 tons (Load and Resistance Factor Rating (LRFR) rating reported by rating factor (RF) method using HL-93 loadings [8])
Appraisal
Structural: Basically intolerable requiring high priority of corrrective action [3]
Deck Geometry: Basically intolerable requiring high priority of corrrective action [3]
Road Alignment: Meets minimum tolerable limits to be left in place as is [4]
Waterway: Superior to present desirable criteria [9] and Bridge foundations determined to be stable for assessed or calculated scour condition. [5]
Inspections
Date: September 1999 [999] and Frequency: 24
Future Work
Work Needed: Bridge rehabilitation because of general structure deterioration or inadequate strength. [35]
Bridge Detour: 0 km = 0.0 mi
Traffic
ADT: 99 (0) and Trucks: 0%
Future ADT: 148 (In 2041
)
