How to give impact load in STAAD Pro V8i

[ARNAR]

How to give impact load in staad. i need to check the system will pass the soft body ( 300 joule) and hard body impact test as per the EOTA and ETAG 003. Whats the general procedure to convert the energy (joule or Nm ) to load ( to model in staad ) . Please help me to find a solution .

 

[WARose]

For a impact load in STAAD: You can just put the load in as a quasi-static load (i.e. the load multiplied by a impact factor).

Or: click on the "Load Page" icon (on the toolbar; it looks like a hand above an arrow). Then click "New" (on the (lower) right hand side of the screen; the window with it appears when you click on the "Load Page" icon). Then (under the "Definitions" tab), click on the "Time History", and a "Define Time History" tab should appear. In that window (with the "Define Time vs. Force" & "Force" options selected), you should be able to define your force vs. time.

 

[ARNAR]

@ WARose : Thanks for your advise. i want to check the partition wall system safe against the soft body impact test. In soft body impact test, hitting a softy body of mass 50kg with an energy of 300 joule. If i put the load quasi static load what impact factor i need to take ?? if i proceed with time history , how can we find out the force and time using these ( load and energy) ?? please help me to find solution.

 

[klaus.]

These test are usually done as 'real'test...and not as a FE calculation



best regards
Klaus

 

[ARNAR]

@ before that we need to check the system pass or not.

 

[klaus.]

I do not know STAAD...there is a special glass calculation software which can simulate impact on glass
Software is called : SJMEPLA


best regards
Klaus

 

[ARNAR]

@ Klaus Thanks. but here panel is 0.6 mm thk steel with gypsum board backing.

 

[WARose]

[blue](Nirmal Ar)[/blue]

In soft body impact test, hitting a softy body of mass 50kg with an energy of 300 joule. If i put the load quasi static load what impact factor i need to take ??

I think one of the better methods of figuring impact force is the method/formulas in Blodgett's 'Design of Welded Structures' that takes into account stiffness. (See Section 2.8.) You could probably figure it that way.

Another way could be the impulse-momentum equations. I.e. F= mv/Δt. (Where m=mass of object, V=velocity at impact, and Δt= impact time.) The problem with that method is: It's hard to know what the duration of impact will be. (It can range from as high as 300 ms to as low as 0.1 ms. On rare occasion even be shorter than that 0.1.)

 

[ARNAR]

@ warose what is formula in Blodgett's 'Design of Welded Structures' ??

 

[WARose]

[blue](Nirmal Ar)[/blue]

@ warose what is formula in Blodgett's 'Design of Welded Structures' ??

Probably the most relevant one:

F= W[sub]b[/sub] + (W[sub]b[/sub][sup]2[/sup] + ((K*W[sub]b[/sub]*V[sup]2[/sup])/g))[sup]1/2[/sup]

Where:

F= Impact Force [lbs]

W[sub]b[/sub]= weight of body [lbs]

K= stiffness at point of impact [lbs/inch]

V= Velocity at impact [in/sec]

g= acceleration of gravity [386.4 in/sec[sup]2[/sup]]

This formula is built around a falling object striking a beam with one degree of freedom.