Steel Bridge Load Rating Parameters
Select the Load Rating Parameter for Steel Bridge Load Rating design.
From the Main Menu select Rating > Steel Bridge > Rating Parameters
System Factor
Input the System Factor to be applied to the normal resistance, which reflects the level of the complete superstructure system.
Strength Limit State
Check on to perform load rating in strength limit state.
Strength Resistance Factor
Girder Type for Box/Tub Section
Single Box Sections: If the Single Box Sections option is selected, St.Venant torsion and distortion stresses need to be taken into account. The value of distortion stress is determined based on the input value of "Warping Stress Range" option in Fatigue Parameter.
Multiple Box Sections
Consider St.Venant Torsion and Distortion Stresses: Check on to consider St.Venant torsion in accordance with distortion stress. In case of multiple box sections, St.Venant torsion and distortion stresses may be neglected if the relevant conditions (Article 6.11.2.3) are satisfied. The value of distortion stress is determined based on the input value of "Warping Stress Range" option in Fatigue Parameter.
Option for Strength Limit State
Appendix A6 for Negative Flexure Resistance in Web Compact/Noncompact Sections: Check on to apply Appendix A6 for the flexure strength of straight composite I-sections in negative flexure with compact/ noncompact webs. Use of Appendix A6 is optional in accordance with the code.
Mn≤1.3RhMy in Positive Flexure and Compact Sections(6.10.7.1.2-3): If the three conditions below are not satisfied for the compact sections under positive flexure in a continuous span, the Mn value is restricted to 1.3RhMy.
- The span under consideration and all adjacent interior pier sections satisfy the requirements of Article B6.2,
- The appropriate value of θRL from Article B6.6.2 exceeds 0.009 radians at all adjacent interior-pier sections
- In which case the nominal flexural resistance of the section is not subject to the limitation of Eq. 6.10.7.1.2-3.
Post-buckling Tension-field Action for Shear Resistance (6.10.9.3.2): Check on to consider post buckling resistance due to tension field action in the nominal shear resistance of an interior stiffened web panel.
Service Limit State
Check on to perform load rating in strength limit state.
Limiting Stresses in Structural Steel
Auto-Calculation
Design Load: fR = 0.95 RhFyf
Legal/Permit Load: fR = 0.95 Fyk
User Input
Design Load
Compressive stress:Input the limit state compressive stress.
Tensile stress:Input the limit state tensile stress.
Legal/Permit Load
Compressive stress:Input the limit state compressive stress.
Tensile stress:Input the limit state tensile stress.
Fatigue Limit State
Check on to perform load rating in strength limit state.
Application of Diagnostic Test Result
Load Measurement: Adjustment factor resulting from the comparison of measured test behavior with the analytical model can be calculated. Select between Strain and Displacement obtained from the diagnostic test. Measured value can be entered in Diagnostic Test Results menu.