Impact load for steel beam 1

[engr567]

I need to design a steel beam for impact load. Does AISC manual have a provision for this kind of design? I would appreciate any help.

 

[ToadJones]

usually just involves factoring your load with an impact factor and in the case of repeated loading, checking for fatigue.

 

[engr567]

ToadJones,

Thanks for the very quick response.

Do you know how to calculate impact factor (section in AISC 13th ed.)?

 

[csd72]

A little more information will give you a more specific response.

 

[engr567]

This is a pulley system (2000 lbs maximum load) to lift and move loads from one end to another end of the beam.

 

[ishvaaag]

You can find guide at a number of publications. For example the
AISC Steel Design Guide Series, number 7 Industrial Buildings Roofs to column Anchorage.

 

[ToadJones]

like a monorail?

 

[ChipB]

enr567,
I don't know where it is in the 13th Edition, or if it is even in there.

Unless it has changed recently, the "minimum" impact load is 1.15(W) where W includes the weight of the hoist itself.

To this 1.15 number, you have to add 0.05 for every ft/min of your hoist lifting speed up to a "maximum" impact factor of 1.5

Try to locate the publication ANSI MH27.1
It will be in there under section 6, I believe.

FYI, our company's design minimum impact factor starts at 1.25 and goes up to 1.5

Hope this helps!

 

[delagina]

check ibc or asce

 

[ToadJones]

MH27.1 is patented tracks, no?

 

[ChipB]

Toad,
Yes, but why would one want to design to less than what is considered acceptable by the manufacturers of the hoist equipment. Even though I've never patented any monorail I've designed, I've designed based on this publication. I've been in a plant where the monorail's deflection exceeded the amount of slope the hoist could move the load. It wasn't pretty.

My $0.02, and I guarantee anyone else who's been in the industrial business for long, would throw their $0.02 in on top of mine.