Questions related to SAP 2000
I am not getting blast pressure value for 15m stand off distance using ABAQUS software. It is showing zero blast pressure. But journal results shows some value using SAP 2000 software.
I'm facing difficulty in modeling different link elements (MLE, MLP, Hook, Gap, and Spring) in series or parallel to exhibit the super-elastic behavior of SMA in the SAP 2000 software. I'm not getting the approach to how to model it in SAP 2000.
Could anyone please help me with the modeling approach?
It would be a great help.
Kindly, I wanted to perform several Non-Linear Time History Analyses in SAP2000 software on a single degree of freedom system by changing several parameters such as Time period, damping, and hysteresis curve parameters...
Is there any way to perform these analyses without running the model every time? for example by generating a code (loop) or something similar.
Any help is much appreciated.
I am modeling an underground structure with fixed support conditions around the exterior walls. I would like to apply different ground acceleration time history data into specific nodes (joints) of the structure. Is this possible in SAP 2000? I would appreciate any guidelines. Thank you very much!
Good morning, greetings from Peru. I have a question. How is the critical elastic buckling load of a building calculated in Etabs or SAP 2000?
For my graduation project I need to determine the cost of buckling restrained braces of different sizes and properties. Does anyone know how much is the approximate cost of each one and the cost of the tests required? For example, for the case of fluid viscous dampers, there are relationships in the literature of the type Cost = A*ForceDamper^b that allow estimating its cost.
Does anyone know if there are similar relationships exist for BRBs?
P.S. I have tried to contact some manufacturers but that kind of information is confidential
i am trying to analyze a water tank which is made of steel and placed inside my building, is this method sufficient to model that fluid structure interaction ?
initially i decided to perform non linear time history analysis on SAP 2000 but my sir suggested me to create analyze and design the model in ETABS and then export to SAP 2000, but after creating the model we are unable to import it in SAP 2000 as we are getting errors so i have decided to perform non linear time history analysis in ETABS19, so please let me know is it possible?
I've been learning how to compute the incremental dynamic analysis with sap and now I wanna check if my analysis is at 100% good. So I'm looking some written papers about a Sap model for incremental dynamic analysis. My goal is to compute my own incremental dynamic analysis with that model so I can compare my results with the author's result.
Thanks in advance.
#IDA #incrementaldynamicanalysis #SAP2000
I will really appreciate if anyone could give some tips on the use of Lusas and SAP 2000 software for modeling and structural analysis. Thanks
Hello fellow practitioners. I Have a quick question please. I am currently verifying the resistance of a column that is reinforced with different type of steel. On the edges we have a total of 12 #6 bars with a yielding stress of 275 MPa. in the center of the column we added one #18 bar with a yielding stress of 517 MPa. I tried to find the answer on the code. But it doesn't discuss how to calculate Mr when the yield stress of steel is not uniform.
I am trying to analyze a 2D four-level frame structure that is formed by concrete columns and concrete beams. The original building from where I obtained the frame is a university structure here in Perú. I considered the sections and reinforcements according to constrution plans.
I used user defined hinges that were created by a moment-rotation analysis considerating concrete and steel models. I consider a certain level of axial load in order to obtain moment-rotation diagrams in columns. I didn´t use any automatic hinge definition (ASCE or FEMA) because I would like to obtain results acordding to my own constituve models. I created different hinges for columns and beams and I placed them in every extreme side in columns and beam and in the middle of beams.
The seismic record is Lima 1974 earthquake and I scaled it to a 0.45g aceleration that belong to the maximun aceleration in peruvian seismic resistant norm. The original unit of the seismic record is cm/seg2. I think this is a good level of earthquake in order to generated an inelastic response in the hinges. For that reason I used a scale factor of 0.0247 that means to convert the units cm/seg2 to m/seg2 (x 0.01) and I also considered the value of 2.47 to scale the maximun aceleration of the seismic record to the value of 0.45g. At the end, the scale factor results in 0.01 x 2.47 = 0.0247.
In the nonlinear time history case I also used a initial nonlinear case in order to obtain more degradation (Gravity loads). I also defined geometric nonlinearity parameters in order to obtain more displacements.
The problem is that I didn't obtain a good strength degradation of the hinges and they seem to have a elastic degradation response. For that reason, I ask for your help because I don´t find the problem in the model definition. I check my moment-rotation diagrams and don't have any problem or error.
I would apreciated some help and I share the model definition with all the things that I defined in the analysis.
Which code and clause use for that relative distance of plastich hingest.
I did the calculation of static wave forces by applying the Morison equation, i was able to obtain the shear and the moments. What I need is to transfer this forces to a model that allows me to obtain the displacement due to this forces.
I tried to use Sap and Robot but I didn't know hot to introduce this shear and moment value along the pile depth, considering the pile a beam.
I would like to carry out a non-linear static analysis but considering my structure's natural modes, and I would like to know how I can set this up in the SAP2000 software
I have tried to consult the user manuals but I have not found anything about the modal pushover analysis.
In the definition of loads for the non-linear static analysis (as show the image below) , there is a section where you are asked to define the modal loads, but I don't really understand what this image is about, and the concept.
I would like you to help me define the modal loads and to understand the concept or basically I would like you to help me perform a pushover modal analysis on SAP2000.
I am currently working on a single story model where beams and columns are made of RCC and truss is made of timber. Timber section is designed using section designer in SAP 20000. After analysis base shear, joint displacements etc. values are vary large which is unexpectable.
Does anyone have knowledge regarding this please shear with me it will be very helpful for me.
I want to model an uplift restraint friction pendulum isolator(FPS) using SAP 2000. CSI referece manual has mentioned about Double-Acting Friction-Pendulum Isolator element which is based on the work by Roussis and Constantinou (2005) on the uplift restraint FPS. But such a link element is not directly available in SAP 2000. Can somebody suggest me a method by which I can model the uplift restraint FPS in SAP 2000.
While running non-linear analysis in ETABS I am getting the following error.
* * * W A R N I N G * * *
THE P-M-M INTERACTION SURFACE IS NOT CONVEX,
HINGE PROPERTY: C3H2,
RELATIVE ERROR = 0.010275, THE SURFACE WAS ABLE TO BE ADJUSTED
Can anyone of you who have faced a similar problem can share the reason or solution to fix this error?
I created a finite element model of steel truss bridge and tried to do a modal analysis to generate the natural frequencies and mode shapes. Unfortunately, i don't get deformed shapes, but rather the SAP 2000 software will add more constraints at the middle spans of the bridge. Furthermore, negative Eigen values are also generated. Please i need help. Find the screen shot of the bridge before the modal analysis and after the modal analysis.
I'm currently doing a project on cantilever retaining wall provided a key also. I want to know use of SAP 2000 software for stability checks and design and reinforcement details for specific project by getting idea from solved example. Thanks
I am using sap 2000 to simulate a braced frame for pushover analysis. To simulate nonlinearity, I used automatic FEMA hinge properties. But sap 2000 has a negative stiffness slope restrict about %10. So I couldn't see the behavior of hinge as given in FEMA.
Why does sap 2000 limit the slope?
I'm trying to design the Rocking frame structure in Sap 2000 with an Energy dissipation element ''Shear Fuses'' at the base of the structure.
Would you please suggest how to model an element that has the same properties as a shear fuse?
As you know, one of the challenges of using nonlinear procedures is to determine the behavior of plastic hinges of members with deformation controlled action that this behavior is assigned to the plastic hinge by a force-deformation curve and its relations using parameters modeling. various researches has shown that the uncertainties in these modeling parameters significantly affect the structural responses.
Also, the acceptance criteria of different performance levels relating to the mentioned force-deformation curve are needed for performance-based design of structures.
There are two questions now:
1- Are force-deformation curves presented in ASCE 41-13 suitable only for nonlinear static analysis (push over)? or also is applicable for nonlinear dynamic analysis?
2- Given that the acceptance criteria presented in ASCE 41-13 are derived based on the mentioned force-deformation relations in this code (a, b and c modeling parameters), what acceptance criteria can be used to evaluate the structure at the IO, LS and CP performance levels if the other force-deformation relations presented in the technical literature (such as Lignos and Hartloper relations for beams and columns of moment frames, respectively) are utilized for concentrated plasticity modeling?
The mentioned curves (Lignos and Hartloper relations) are mostly used in structural modeling to study the structural collapse, in which the collapse is determined by the criteria mentioned in FEMA p-695 and as a result, acceptance criteria in accordance with these behavior curves have not been researched.
I am doing my project using IS 1893 and working with pushover analysis. I needed to input the IS 1893 response spectrum as the demand spectrum. Can anyone please explain how to do it?
Suppose i define the RS earlier in functions, what should the scale factor be? Please refer to the image attached. What is the value of SF?
In pushover analysis,while defining lateral load pattern for there is actually two options available 1. mode 2. ACC. Mode pattern considers the pattern as the mode shape of the structure analysed. What does the 'ACC' mean? how the load is distributed along the structure?
I have observed that there are usually a dip in the spectral ordinate (Sa/g) at short period (<0.1s) for the ground motions obtained using stochastic simulation (SMSIM). I have attached a figure highlighting this. The same can be observed for the spectra obtained using some GMPEs (which are developed using synthetic ground motions).
However, I have seen this dip to be absent in the median spectra (Sa/g) of horizontal component obtained using recorded ground motions or the spectra obtained using GMPEs (which are developed using recorded ground motions).
I believe this dip is due to spectral De-amplification for which is higher in medium/stiff soil site and covered in SMSIM. What is the reason that this dip is not observed in recorded data?
However, this may also lead to inconsistency in GMPEs for the same region generated using real ground motions and synthetic ground motions.
I am particularly new in this area and would really appreciate some answers.
Eccentrically Braced Frame building of 6 story modeled in SAP 2000. Conducting a non-linear dynamic response to earthquakes.
when i assign hinges for beam and column before pushover analysis in SAP 2000,. a error is shown related to assigning hinges . How can i overcome from this issue?
kindly help me if someone find solution of it.
Hello every one,
I am doing analysis of Bridge in which elastomeric bearing is modeled as link element between Deck and pier bent. Pier bent portal consist 2 pier and one cap beam on which elastomeric bearing are resting and on elastomeric bearing bridge deck is rest. I am doing non linear time history analysis.
Now (1 )due to elastomeric bearing, moment/forces are not transferred to pier hence bottom moment of pier has not reached Mp value and stresses in pier is very less (at least half of yield stress of Concrete)
(2) Joint Forces at link bottom has reached maximum level of forces and for bearing perfect elastoplastic force displacement curve has given as input of link
(3) Even if pier concrete has not reached at yield stress level CSI Bridge & SAP2000 showing hinges from IO to CP at various time steps.
Why does SAP 2000 Showing hinges in pier even if pier has not undergo plastic moment? Does it is due to yielding of Bearing
In a followup question to what was previously asked, which of the following would you recommend for analysis and performing design checks on 3D frames:
(5) RISA 3d
(6) Autodesk ROBOT
my question is not on how to define the harmonic or time history load from the pedestrians,the question is, it is already defined on the load case but how to assign it(applying it) on the deck before running the model?
i needed to do a sensitivity analysis o n my updating parameters to identify which ones affect the dynamic response of the bridge under investigation. I use the SAP 2000 software
I am trying to model steel plate shear walls in SAP 2000. First I should define an orthotropic steel material and define nonlinear parameter of it ( Stress-Strain curvature) in somehow to neglect compression stresses then I should define a shell/layered-nonlinear and define which stress component ( S11, S22, and S12) is nonlinear.
I've been performing non-linear static pushover analysis for Progressive Collapse analysis of structure using load controlled analysis. How to plot the calculated pushover curve from the analysis results, since load controlled pushover analysis is not giving the pushover curve?
Drucker-Prager Properties used in SAP2000 for concrete only refer to friction angle and dilatation angle while the hysteresis curves also are limited.
Purpose: To calibrate SAP 2000 model with Abaqus model.
P.s: Attached the nonlinear properties of concrete in SAP2000
I'm currently working on pushover analysis for multi-story structures on ETABS 17.1. The calculation time that it took was 96+ hours that too, for a building of 20 floors. I've many models to run, and some are even of 80 stories. Can someone suggest ways to reduce its calculation time for the structure?
Hi everyone, I am doing a my MSc. dissertation on Earthquake Resistance Techniques in Buildings, I want to compare results of two techniques on the same building. I have created model of a structure in ETABS and SAP 2000. Now i want to introduce Base Isolation and Damper ( separately ) using any of above-mentioned software. Can someone please tell me how do i start working on that ? Theoretically i know the idea of it but on SAP or ETABS how do i approach the problem ? Please describe it step by step and also for both ( BASE ISOLATION - Rubber Lead ) and ( DAMPERS ).
In SAP 2000, various hinges are available . I just want to know the type of hinge (viz interacting P M2, fibre PM2 M3 or parametric PM2M3) which is best suite for capturing non linear response by nonlinear time history analysis.
What is the proper procedure of applying vehicular load on grillage .
Do we define a path for vehicle or do we distribute the vehicular load on nodes of the grillage members. I am using SAP 2000
I am using Sap 2000 for Nonlinear time history analysis in my research, and I have a concern regarding the maximum forces that result from the analysis, Is it the max force causing failure of the structure?
is there is any indication for the force reached such as that color coding in push over analysis that show the user if he/she reached the collapse or not yet ( Although the above mentioned analyses are different but there should be a point where the program indicates the collapse)
I appreciate your input.
I want to add some ground motion data for time history analysis from PEER database as those are not given in ETABS in its default saving files.
Building exhibit torsional rotation under seismic loading due distance between the center of mass and center of rigidity. According to building codes, does this distance or torsional rotation have any limitations? And if not, how could I check the capacity of building for large torsional rotation?
Could the layout of the shear walls in multi story building induce torsional rotation due to dead load only?
I faced this problem when analyzing a building in Etabs.
I need to calculate DCR (demand capacity ratios) for different members in an RCC building for progressive collapse under column removed condition. SAP 2000 software has been used for analysis. Under which load combination should the DCR values be calculated? Will DCR values be same for non-linear static and dynamic analyses?
Are the DCR values same as the PMM ratios that we get from SAP analysis results? Otherwise how to calculate the same?
I am modeling mat foundation in sap 2000. and I am a bit concerned on the use of line spring elements since they can carry both tension and compression. but, the area spring option allows me to define my springs as compression or tension only. I have modeled using both and the line spring gives higher moment and shear while the area spring yields a lesser value.
so I need clarification on which i should use.
hi, I have a results of experimantal explosion(pressure-time history). I am modelling shell using SAP 2000. I need a displacement on shell after blast analysis. For this I must add grid on shell and load(pressure-time history) assign to this grid.
How can I do it ? help me
I'm currently working on Progressive collapse of earthquake resistant RC building subjected to column failure. I need to plot the graph of vertical displacement vs percentage load carried under all column removal cases. How can I do the same?
I am working on rotational seismology, and I want to give rotational ground motion data as a input in SAP 2000, and want to check the torsional mode shapes of structure, and want to study about effects of rotational component of ground motion data, If any other software is available for this purpose then please suggest me that also.
I want to place a shear hinge in the middle of one story Eccentrically Braced Frame shear link and assign a bilinear force-rotation curve with a strain hardening slope of 10% of the elastic stiffness for nonlinear static analysis. I want to verify my design through this.
Any ideas how I can assign this in SAP 2000?
I have to define relative hinge distance for auto hinges.
What distance can I take? Also I need to know the auto hinge length to define it.
I have two questions:
1st question: I need the steps to follow for time history analysis for a gravity dam by including dead and hydrostatic pressure
I did a test, and I want to know if it is correct or not (see the attached file)
2nd question: is it possible that time history analysis gives larger displacements than Response Spectrum Analysis
I am modeling the Masonry building in SAP 2000 as a solid element. I have modeled the interventions such as Steel plates as a linear element over the solid masonry element.And to some extent the results obtained after the interventions are satisfactory. However I am not sure if SAP2000 is compatible to model such composites.
I need some help to applicate a pushover analysis for concrete gravity dam:
the steps to follow ?
how to introduce the sources of non linearity (joint of resumption of concreting and the contact dam foundation) ?
It is possible to joint hinge if i am using Solid Element to modelate the dam?
The hinges are formed at fist in column then only in Beam . Can anyone help me with this?
For analysis purposes the Brick infill is to be represented by the Equivalent diagonal Strut. In case of Non-linear Analysis how to define the plastic Hinge properties for such Struts in SAP 2000?