LEAP Bridge Steel (LBS)

• The program can operate on one bridge at a time. The database may contain more than one bridge, and the user can select the bridge to be worked on. Multiple bridges can be shown on the Main Interface by accessing view all bridges check box.

• LEAP Bridge Steel and LBC Substructure do not support multiple column types defined for the same pier; once a column shape is settled for one column the others will take the same shape.
• LBS currently not using AASHTO Appendix A6.
• Deck reinforcing steel and shear connectors not showed in 3D view.
• For fatigue design, LBS currently does not consider flange lateral bending effects.
• For local and lateral torsional buckling checks, LBS uses only the maximum flange lateral bending stress (f_l) within the bracing range.
• LBS currently performs load rating for design Inventory and Operating only. Only main members are rated at this time. Cross frames, bearing stiffeners, etc. are not rated.
• LBS automatically includes the provisions of Article D6.4.1 when computing lateral torsional buckling resistance.
• Design Optimization applies to the final design stage only (does not apply to construction stages)

LBC Substructure

• Substructure types not supported for current version: wall pier, pile bent, wing walls.
• LBC Substructure does not design back wall. It uses back wall only to find out self-weight using the geometry defined on the configuration dialog.
• For pile cap design option, program assumes the frame model as pile cap and piles connected at the mid height of the cap.
• Eccentricity of bearing line is defined from center line of stem.
• For pile cap footing, if there are more than 1 pile in each row, analysis program combines the section properties and treats it like a single pile defined at the center line of the footing. The pile design information is for the combined section properties.
• LBC Substructure assumes free condition at the top of abutment.
• For stem wall design, program designs only at top and bottom of the column. If users want to check the design at various locations, then check points must be defined in the structural model.
• The trapezoidal Earth load is applied with the maximum applied at the bottom of the footing and 0 at the top of the back wall.
• LBC Substructure does not design footing for shear.
• For multiple piles in stem wall design option, forces are distributed equally.