How to find the total mass modeled in the Mass Reference Load case?
Applies To
Product(s):
STAAD.Pro
Version(s):
ALL
Environment:
ALL
Area:
Analysis Solutions
Subarea:
Dynamic Analysis
Original Author:
Modestas Turulis, Bentley Technical…
Mass is a scalar value!
A common error for beginners in structural dynamics is to forget that mass is a scalar value. Therefore, the masses input listed below must have the same value in all three global axis directions ! Moreover, the user should remember that the l oads of…
How Do I Model Mass For A Dynamic Analysis?
Applies To
Product(s):
STAAD.Pro
Version(s):
ALL
Environment:
ALL
Area:
Analysis
Subarea:
Dynamic Analysis
Original Author:
Phil Riegel, Bentley Technical Support Group…
Mass Source Options
This document explains how to define masses in RAM Elements and what are the available options for the source of such masses.
1.1 Mass source
The mass source must be understood as the actual mass that will be used in the modal analysis. The modal…
Are Superimposed Dead Loads added to the Mass?
Are superimposed dead loads applied in the forms of line, area, and point loads added to the mass in RAM Frame automatically or does the user need to add the dead load into the "Dead Load" AND "Mass Dead Load" dialog?
The following links only describe…
Extracting weight of model in Prevue
Hi all,
A new user of SACS here. Is there a way to extract the weight of certain group members or plates in Prevue? Any help would be greatly appreciated. Thanks!
Best Regards,
Naz
ERROR IN MODAL RESPONSE SPECTRUM ANALYSIS, VALUES FY, FZ 0.00 FOR MODAL BASE ACTIONS mass participation factor in percent FY ,FZ values 0.00, Base shear Y, Z =0.00
i have next problem, with the mass participation factor in percent FY ,FZ values 0.00, Base shear Y, Z =0.00
ATTACHED MODEL: STAAD SPACE START JOB INFORMATION ENGINEER DATE 19-Apr-18 END JOB INFORMATION INPUT WIDTH 79 INPUT WIDTH 79 UNIT METER MTON…
RE: Seismic Analysis
Any load that is included as part of the mass definition for a dynamic load case ( like response spectrum or time history or even a simple frequency calculation ) will be considered. So ensure that you include the loads due to these equipment as part…
RE: Mass Dead Load vs Dead Load
The Mass Dead Loads are used only in the generation of seismic loads and is considered in the lateral load analysis. For the gravity analysis, you need to define Dead Load.
*Error* No unsupported masses entered - check densities
Hello,
I am currently running a simple building design and i have entered the attached editor file with this post. I am getting
*Error* No unsupported masses entered - check densities
Error in the solver.
Kindly address my issue.
***WARNING: MASSES DEFINED UNDER LOAD# 20 IS CONSIDERED FOR RESPONSE SPECTRUM ANALYSIS. THE MASSES DEFINED UNDER LOAD# 21 IS IGNORED.
HI ALL I NEED HELP WITH THIS WARNING,I NEED A SOLUTION .
RE: Calculate mass and center of mass for a single floor
Is the problem specific to the model you are working on or does it affect any file? If it's model specific, please send back the file. Also let us know the version you are using. We were running into a problem for models with shells but with no rigid…
Basis for the suggested added mass and damping for launch barges
Q: What is the basis for the suggested added mass and damping for launch barges? REV 7.04
A: Originally these numbers were based on the high frequency results in a frequency domain analysis for nominal launch barge in a nominal launch position. These…
Compute the added mass on a plate
Q: How does MOSES compute the added mass on a plate? REV 7.02
A: The added mass for plates and #PLATES is computed as defined in DNV Classification Notes 30.5; i.e. the added mass depends on the aspect ratio of the submerged portion of the plate. For…
I added dead+live load as seismic mass. Do I need need to define these loads separately too ?
Applies To
Product(s):
STAAD.Pro
Version(s):
All
Environment:
N/A
Area:
Analysis Solutions
Subarea:
Response Spectrum Analysis
Original Author:
Sye Chakraborty Bentley…
Added mass coefficient
Q: Is the added mass coefficient reported by MOSES the total added mass? In other words, will the total added mass be the displacement x the added mass coefficient reported or displacement x (1 + added mass coefficient reported). REV 7.01
A: This is…
RE: Mass Dead Load
Mass DL is used in seismic loads (and dynamic analysis). It may be the same as the Dead Load but does not have to be. More here: https://communities.bentley.com/Products/Structural/Structural_Analysis___Design/w/Structural_Analysis_and_Design__Wiki/ramss…
RE: REFERENCE LOAD
Your conclusions are correct. Regarding your doubts, here are the responses
1. Seismic weight for static seismic analysis won't be calculated by itself and have to be separately defined?
No. When you define a mass type reference load, you DO NOT need…
RE: Reference loads for seismic mass in response spectrum analysis
Assuming that you are NOT using Reference Loads, you only need to define the mass as part of the first response spectrum load case. The second and third response spectrum cases should only contain the spectra. If you specify masses as part of the second…
RE: Time history Analysis for a forcing moment.
The moment in this case is the dynamic force that is acting on the mass and need not be considered in the mass modeling. For mass modeling you should only consider items like dead load and other superimposed loads of permanent nature. I created a quick…
RE: Combining Mass and Gravity Loads to Diaphragms
Using the combine to option in Ram Frame - loads - masses is always all or nothing, the entire diaphragm mass gets lumped to the target diaphragm and added at the center of mass. To have more control, i.e. to split the mass to two target diaphragms, you…
RAM Elements: Mass of members for modal analysis
Hello,
I am using RAM Elements (V8i, release 13.3.0.117) to model an industrial steel building with long-span roof trusses and perimeter braced frames. I will be running a dynamic response spectrum analysis. For the gravity load case I have a self-weight…
RAM Frame - Masses
Product(s):
RAM Structural System; RAM Frame
Version(s):
Any
Environment:
N/A
Area:
Analysis
Original Author:
Bentley Technical Support Group
Why do I get a warning about mass that's not associated…
RAM Frame - Center of Rigidity
Product(s):
RAM Structural System
Version(s):
Any
Area:
Analysis; Reports
Center of Rigidity
In order to review the center of rigidity for a structure, a special Centers of Rigidity load case must be created under…
RAM Frame - Seismic Loads [FAQ]
Product(s):
RAM Structural System; RAM Frame
Version(s):
Any
Environment:
N/A
Area:
Analysis
Original Author:
Bentley Technical Support Group
How are torsional irregularities considered?
In…