total modal mass exceeding 100%

[langxuzeng]

Hi all,
Recetly,Iam carrying out nonlinear analysis for a simple stack-like structure and meet with several problems as folowing:
Q1:How to output the total mass of the whole structure? Does SeismoStruct have this ability ?
Q2:How to output the step in which the user defined material criterias were reached ?
Q3:The first two nodes of the link element are the same node?
Q4:what is the reason that Cumulative Mass can reach 104.24994% in eigenvalue analysis ?
Would you please give me some benefinal guidence for these simple questions?
Thank you in advance.

[fbianchi]

Hi langxuzeng,

I try to answer to your queries..
A1: In order to get the total mass you just need to run an Eigenvalue analysis, then go to the Post-Processor -> Modal/Mass Quantities -> Nodal Masses, copy and paste the values in a spreadsheet and do the sum (see also the following post: http://www.seismosoft.com/forum/topic.a ... total,mass)
A2: In Post-Processor -> Global Response Parameters -> Performance Criteria Checks you can select the option "Only Criteria Reached" but you have to select the step output manually
A3: The first two nodes that are necessary in order to define a link element must be coincident (they must have the same coordinates)
A4: Which version of the software are you using? I suggest you to send your model to the technical support)

Regards,

[langxuzeng]

Dear fbianchi,
Firstly,I have to thank you for your patient explanation for these simple questions.Your answers do really help me.I will try to perform the analysis according to your guidance.The version Iam using is the Version 6 build 100.I think maybe there are undetected errors in my model.Iam testing my model.Soon,I will post my results.If the strange phenomenon would be disappear,I would send my model to the Seismosoft Support to ask for help.Again,thank you for your suggestion.
Best regards.

[seismosoft]

Dear langxuzeng,

We have ran an analysis with your model and did observe total mass values above 100%, which is certainly incorrect.

We will look into this issue further and try to resolve the problem.

Many thanks,

Seismosoft Support