Suspended Flat Slab Platform

[engstructural]

I have to design a small flat slab platform approx. 12.5 X 15.0m. it will be supported by a grid of end-baering precast or mini piles. The platform is loaded with plant approx. 3.5kN/m2. (Will be designed by hand)

1. a small crane may have to be supported on the slab maybe 2-3 times in the life of the project. What loading would be appropriate or can the piles be positioned to support crane jacks. (I have looked as BD37/01 but these loadings would seem extreme given the usage.)

As I am designing by hand I would like to use UDL loads not knife edge loads of points.

 

[gwynn]

You really need to know what crane is being used, what it is lifting and at what radius in order to come up with outrigger or wheel loadings. You can specify that outrigger pads of a specific size are to be used in order to spread the load out some.

The easiest case is probably to space the piles to meet the outrigger configuration, for which you definately need to know the crane being used. If a different crane is used they may have to use outrigger beams to support it.

Or, without knowing the actual crane, you at least need to know the weight being picked and the maximum size of the crane. Then you are looking at an area load consisting of the entire weight of the crane plus the weight lifted over a portion of the slab.

 

[engstructural]

Yes this is the issue. As per your second point would you take the total weight of the crane and load as acting on one riggger. I guestt with the crane counter weights I hoped some weight would still be on other riggers and less on the critical one.

 

[ali07]

Remember one time max. loading shall be your govering loading, or see the case below:

 

[ali07]

See these images also: