Elastoplastic moment hinge in SAP2000

[sugantha]

Hi,
I want to assign elastoplastic hinge at the end of each beam and column element for Non-linear dynamic time history analysis of 2d frame.What should be the input for assigning a moment hinge with elastoplastic behaviour if deformation controlled hinge option with Isotrophic hystersis type is used.??
Is it possible to achieve the same with the help of link element(WEN PLASTIC ELEMENT)...??

 

[mronlinetutor]

u can try using the pushover analysis capability of sap2000.

pushover analysis allows u to define the plastic hinges and their locations. I don't know whether it will define an elastoplastic hinge though.

a quick search on the google gets the following:


Create the computational model
•Create the computational model, without pushover data, using conventional modeling techniques.
•Define properties for pushover hinges using Define > Section Properties > Hinge Properties. Hinges may be defined manually or by using one of several default specifications which are available.
•Assign the pushover hinges to selected frame objects using Assign > Frame > Hinges.
•Select Define > Load Patterns to define load patterns which will contain the loads applied during pushover analysis.

Define a nonlinear static load case
•Select Define > Load Cases > Add New Load Case to define a nonlinear static load case which will apply the previously-defined load pattern. This load case may be force-controlled (pushed to a specified force level) or displacement-controlled (pushed to a specified displacement).
•Select Other Parameters > Results Saved to Multiple States such that various parameters may be plotted for each increment of applied loading.

Run the analysis
•Select Analyze > Run Analysis to run the static-pushover analysis.

Review results
•To plot base shear vs. monitored displacement, select Display > Show Static Pushover Curve. Additional variables are also available for plotting.
•To plot hinge deformation vs. applied loading, select Display > Show Hinge Results. Moment as a function of plastic rotation is one such option.
•To review displacement and the step-by-step sequence of hinge formation, select Display > Show Deformed Shape.
•To review member forces on a step-by-step basis, select Display > Show Forces/Stresses > Frames/Cables.
•Select Display > Show Plot Functions to plot response at each step of the pushover analysis, including joint displacement, frame member forces, etc



disclaimer: all calculations and comments must be checked by senior engineers before they are taken to be good.