The OpenSees Community

TsarpalisD wrote: > Hello SadeghSalimian, > I found a different bug in the code. I guess it is proper to post it here: > The geometric nonlinear stiffness matrix (for p-delta) is calculated wrong at so the > results are not valid (I compared with SAP2000 and they are completely different). > So, i r...

Hi, Dear petras unfortunately there is no API to use of OpenSees in .Net Framework. but I used .Net and C# to write the TCL file and run it automatically by c# for optimization purposes. for more information contact me :icn2083@gmail.com

Hi dear TsarpalisD I have found a bug too and I need to fix it. The Bug I found is when a "geometry transformation" object is defined with "joint offset" for considering rigid zone in this element, the stiffness matrix doesn't change. Since this element is the most similar elemen...

Hi every one. my question is how can a thick shell be modeled in Opensees especially for modal analysis? I mean which element is suitable to model a shell element which could consider shear displacement that is introducing in shell theory. Sap2000 enjoys thin and thick shell element . (in comparison...

apparently after removing panel zones the frame stiffness (or less likely the masses) has changed significantly. could you put your code here for examination?

Hi dear friends :) . I need to model a bi-linear material with the same behavior in tension and compression. this material will be used in ADAS dampers. my question is which material is the most suitable to model this behavior? do I use a set of parallel or series materials and can parallel or serie...

in some cases especially that your element is not parallel to global axis according to command manual you need to calculate a vector representing the direction of the local axis (z) of the element. it means you need an extra calculation to gain this vector. to me I always use the rotation matrices i...

Hi everybody. in some cases and problems sometimes I need to load an element in trapezoidal shape or in other cases I need to load only a part of an element uniformly like those are prevalent in commercial software such as ETABS or SAP2000. but in opensees I could not find it directly. I was wonderi...

it's may be done as I did. but it needs a very accurate programming preferably in C# or MATLAB to read Etabs Models and write what you need into tcl Files. if you are a dab hand in programming , it will be easy for you!.

Hi: dear friends :P . I was wondering if someone could help me and answer my questions. 1): to accomplish P-Delta analysis according to what is mentioned in AISC 2016 or previous versions, is using PDelta GeoTransformation is enough or other attempts must be done? and How can I get the difference fo...

Hi dear friends I want to record basic forces of a series of elastic beam columns in my model. in fact I need to record axial force and moments of each end of element as well as shears on each joint, but I found the recorder for this type of elements includes force command which records forces in th...

I tried to model a 3D truss structure by opensees. the model was simple and analysis method was linear. in fact the model was a 3D truss with linear behavior. unfortunately i faced with a unreasonable error message. I already modeled 2d trusses and was acquainted with truss modeling . but in this ca...