1 (edited by irene 2010-04-22 06:36:11)

Topic: Load deflection graph

Dear sir, i am analyzing a beam to find out the load-deflection of the analysis. In my case, I located only 1 monitor points at the bottom midspan of the beam. Then during analysis, at the graph selection box, i chose the x: (the monitored points which i selected displacement)  y axis: step/iteration (default).  is this correct?

As i read your replies, saying that 2 monitor points need to be selected. 1 which is the displacement and another for the load. If it applies to my analysis, I located 1 monitor points at the bottom midspan of the beam (for displacement). Where shall I located the 2nd monitor point in order to find the load/force? whereby i can get the load-displacement graph? Is the step/iteration in the Y axis similar to the monitored points :load ?

Another question, Im not sure about this;  in the load-displacement graph, after it reaches the highest load and start to fail , usually the load will tend to derease with increase in delfection. But what happens here is vice versa. The load at constant with a decrease in displacement (instead of dropping towards the bigger deflection but drop backwords towards the decreass in deflection) Hope you understand what i mean smile
(I am using atena 2d)

tq

Re: Load deflection graph

Dear Irene, to get the load-displacement graph, you need one monitor for the displacement (to plot on the horizontal axis) and one for the load (vertical axis).
The load can be monitored as External force (in case of force loading) or Reaction (in case of prescribed displacements or when monitoring the reaction at support instead of the applied load).
In most cases, we recommend to apply the load/support through an elastic loading/support plate, where the force/displacement can be applied in a single point - see the <b>Beam Iso.cc2</b> example included in ATENA installation (typically, it is installed into the "c:\Program Files\CervenkaConsulting\AtenaV4\Examples\ATENA Engineering\Tutorial\" directory.