Handling of hyperstatic moments

As of SAP2000 V14.0.0, the flexural design check for prestressed concrete box girder bridge superstructures has been enhanced to fully account for secondary effects from prestress tendon forces. In previous versions of the program, all prestress load was 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.

Load combinations should be created with prestress loading. Hyperstatic cases are not needed and are not used. Instead, the actual forces in the tendons are subtracted from the demand. These are the primary forces. Any additional forces in the concrete are either secondary forces or due to other loads.