How to use Mass model Generator

Applies To
Version(s):CE V22 U9 and above
Environment: ALL
Area: Modeling Solutions
Subarea: Loading
Original Author:Abhisek Mandal, Bentley Technical Support Group


While creating mass model using mass model generator how to activate the primary load cases?

Ans also how to set user defined load factors?


Mass model generator option has been included in Connect edition version 22 update 9 to help the user create seismic mass easily in a file which is already having primary load cases. For generating the seismic mass, either a reference load case of type mass can be created or loads can be added under the first dynamic load case automatically to enable the software to calculate the seismic mass from those loads. More details can be found in help file in the below path.

Home > Modeling > M. Loading Your Model > M. Mass Modeling > M. To generate a mass model

The program will only activate the primary cases with specific load type as listed in help file. So, to activate the primary cases please assign proper load type against each of them. The program will only activate the load cases permissible for taking in mass model. See below snap.

When we click on the mass model generator option, a new window opens where already the permissible load cases are taken into account with some default load factor like 1 for dead load , 0.5 for live load as shown below.

Now if you want some other factors to be used in your case, that can be done with few simple steps. First you need to take all the cases or the required load cases to the left hand side with the arrows as shown above. Now for example we want to use 0.25 load factor for live load case. So, we need to select live load and provide 0.25 as load factor and then move it to the right. You will now see the updated load factor as shown below.

Now click on generate to create the mass reference load case in the model.

Please note once you create a mass reference load case in the model it remains there unless you manually change it. After creating the mass reference load case, if you change any load or add or delete any load under dead and live load case you should manually delete the existing mass reference load case and create a new one. 

The process is also explained in the below link.