live loads 1

[cariboo]

How can i calcutate a live load for a 20T loading shovel? The constructor wants to use crane a and shovel over a slab in two points of load each one with 10T. This points of loading will be separate 2.4m. It will be 35kN/m2 + 20T (this 20T is live load). How can i estimate a settlement for this situation?

 

[csd72]

From memory, when we designed ground slabs for fork lifts we used to use 2times the rated capacity on the front axle (i.e. 20t per tyre in your case). I would expect the shovel to be similar.

To be sure you should ask for the manufacturers details.

 

[cariboo]

In fact, I'll check this information because 20T is approx 400kN/m2 and this live loading will moving on the slab!!! So, 35kN/m2 to slab (approx-40m x 40m)-(dead load) and 20T (two points of load and the distance between them is around 2.4m)...but do you know how any software?

 

[csd72]

cariboo,

20T is a weight, 400kN/m2 is a pressure - no direct relation unless you have a specific area!

20T is actually approx 200kN.

 

[cariboo]

Dear CDS72,

Of course we have an specific area!!!!And we've solved the problem. Thanks for your help!

 

[msucog]

maybe it's me be paranoid, but something doesn't jive about this. may need to check to see if the slab can hold the thing up to begin with. cracking of the slab would essentially make a smaller supporting slab area. that's not to mention the forces exerted by crawling, turning, load handling, etc. and doesn't address "near-edge" conditions. also, it seems like it'd have to be one heck of a slab section to act "rigid".

besides, why wouldn't the contractor take care of doing this analysis and making sure they don't mess up the slab? if something goes bad, you're on the hook for it because it will always be your problem since you did such a swanky analysis...unless this is all just a classroom problem.