Deflection Limits for Low Volume Bridge

[justhumm]

78-ft-ish single span, steel girder bridge. 3 design lanes. Sidewalk on (1) fascia. Over (2) railroad tracks.

Locally-owned, municipal bridge with some DOT oversight.

Local "urban" area with low traffic volume.

NBIS report (2021):
Annual Avg Daily Traffic, AADT: ~8,300, 5% trucks
Future AADT (2041): ~12,300
Future Avg Daily Truck Traffic (2041): ~620

AASHTO 9ed. (2.5.2.6.2, optional) Criteria for Deflection
Vehicular Load L / 800 ~ 1.17 inch
Veh & Ped Load L / 1000 ~ 0.94 inch

State DOT Criteria L / 1200 ~ 0.78 inch

As calculated with current girder section (by software, not thoroughly back-checked yet):
HL-93 deflection ~ 0.64 inch
HL-93 with s/w defl ~ 1.24 inch

Girder depth is restricted because road engineers won't raise the profile and need to maintain clearance above the railroad.

Does anybody know of any semi-legitimate and documented arguments that soften or eliminate the pedestrian / sidewalk load deflection criteria (L/1000)?

Thanks!

 

[BridgeSmith]

The AASHTO deflection criteria are for live load only, so you're ok there. Not sure about the state DOT criteria, but I suspect it's the same.