• AASHTO LRFD 2007 superstructure design for precast concrete composite sections has been implemented. Checks include: stress, flexure, and shear (using MCFT). Show me the Superstructure Design manual
• Fully automated bridge design check per AASHTO Guide Specifications for LRFD Seismic Bridge Design 2009 has been implemented, including pushover analysis when required. Show me how Automated Seismic Design of Bridges works
• Automated handling of secondary prestress force has been implemented for the AASHTO LRFD 2007 superstructure flexural design check for prestressed concrete box girder sections.
• The AASTHO/USGS 2007 response-spectrum function has been added.
• Variable girder spacing along the length of the bridge superstructure is now available.
• Variable reference-point location along the length of the bridge superstructure is now available.
• Alignment of shell local axes in generated bridge models has been enhanced.
• The longitudinal discretization of bridge models is now more uniform in complex models.
• Tendons modeled as elements now allow elastic, creep, shrinkage, and steel-relaxation losses to be directly specified.
• The displacements for constrained joints in staged construction are no longer updated for deflection until they are actually added to the model.
• The Bridge Modeler now allows parametric variations to be specified for the girder spacing in those deck sections that allow for non-uniform girder spacing; Advanced Box Girder, Precast I Girder, Precast U girder, and Steel Girder. The girder spacing will be proportionately adjusted to fit within the specified total width minus the specified overhang distances, whether or not any parametric variations are specified for width, overhang, and/or girder spacing.
• The automatic discretization along the longitudinal direction of the generated linked model for bridge superstructures has been improved to reduce the creation of very short line/area/solid objects near in-span hinges, diaphragms, user-discretization points, and section variations.
• The default wobble coefficient for tendons created in the Bridge Modeler has been changed to 2.0E-4/foot to be in accordance with the value given in the ASHTO LRFD 2007 Table 5.9.5.2.2b-1.
• Tendons in bridge objects now load only objects that are part of the superstructure cross section. Previously they could connect to objects that were part of an integral bent-cap.
• An enhancement was made to the Bridge Modeler for bridge deck sections modeled as areas (shells). The element local-1 axis is now directed along the two element joints that are most nearly parallel to the layout line, running in the up-station direction. This results in the longitudinal stress being S11 for all elements. This was previously done for steel girders. It is now extended to the concrete decks, webs, soffits, and the webs and flanges of U-girders modeled as areas, as may be applicable to different cross sections.
• An enhancement was implemented for the Bridge Modeler that allows parametric variations to be specified for the deck section reference point in the X and Y local directions. This gives more control over the eccentricity of the superstructure with respect to the layout line at widenings and for other situations.
• Detailed design checking has been implemented for precast-concrete girder composite bridge superstructures according to the “AASHTO LRFD 2007” code. Separate design checks are available for stress, flexural capacity, and shear capacity using MCFT (modified compression field theory). Live-load distribution factors can be automatically calculated using code formulae, specified by the user, or determined from detailed 3-D live-load analysis. Results are reported for each precast girder, tributary slab, and/or composite girder/slab assembly, as appropriate. Results include plots of stress, moment demand and capacity, shear demand and capacity, and shear-rebar requirements. Detailed tables showing all results and intermediate values are available for display, printing, and export to Excel or Access.
• The flexural design check for prestressed concrete box girder bridge superstructures has been enhanced to fully account for secondary effects from prestress tendon forces. Previously, all prestress loads were being removed from the demand design combos, including primary and secondary forces, unless hyperstatic load cases representing the secondary forces were added to the combos. Now only the primary prestress forces are being removed, so that the demand will automatically include the secondary forces. There is no longer a need to include hyperstatic load cases in the design combos. The flexural design check now requires tendons to be modeled as elements.
• Three new manuals are available as .PDF files and bound into a single printed volume: Introduction to SAP2000/Bridge, SAP2000/Bridge Seismic Design, and SAP2000/Bridge Superstructure Design.
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