Can someone please explain the difference between the options "Include Non-Composite Moments in Mu" (negative moment values just around pier) and "Exclude Non-Composite Moments from Mu" (negative moment values full span lengths) for Negative Moment Reinforced Design of a prestressed concrete beam? It seems the Mu at the pier is equivalent for both. When would you choose each option?
Explanation as per the LBC User Manual.
Negative Moment Reinforced Design :
Precast/Prestressed Girder can now compute the negative moment reinforced design Moment (Mu), excluding the non-composite momentsas an alternative option. By default, non-composite moments in Mu options will be selected in order to have backward compatibilitywith files generated using older versions of the program. Select the Non-Composite Moments in Mu option to exclude the effect of moment due to self weight of the beam and slab from the total negative moment on the section. When a user chooses to exclude non-composite effects, Precast/Prestressed Girder also removes the moment due to diaphragms or moments due to dead loads on the precast beam.
For more information related to Leap Bridge Concrete program please check the wiki articles in the below mentioned Bentley Communities link.
https://communities.bentley.com/products/bridge_design___engineering/w/bridge_design_and_engineering__wiki/2440/leap-conspan-precast-prestressed-girder
Thanks Vinay.
you are welcome