Design / Loads & analysis

Load Rating

LRFR load rating of a simple-span girder to the AASHTO Manual for Bridge Evaluation: HL-93 inventory and operating, AASHTO legal loads and specialized hauling vehicles with safe posting loads, and FAST Act emergency vehicles, for flexure and shear. Enter the factored resistances and the loads per girder.

Span & sections

Span length, L

Moment sectionFrom the left support

Shear sectionOften the critical section, dv from the bearing

Resistance (factored)

Flexure, φM_nAt the moment section

k-ft

Shear, φV_nAt the shear section

kips

Condition, φ_cTable 6A.4.2.3-1

System, φ_sTable 6A.4.2.4-1

Loads (per girder)

Components, DC

k/ft

Wearing surface, DW

k/ft

Wearing surface thicknessγDW 1.25 if field-measured

Moment DFLanes per girder

—

Shear DF

—

Dynamic load allowance, IM

Legal loads

ADTT, one directionγL 1.45 at 5000+ or unknown, 1.30 at ≤ 1000

trucks

Riding surfaceLegal-load IM on spans over 40 ft