Special tower crane anchorage.

[miguelandrade]

Hello,

We are about to start to mount the metalic structure of a 50m tal building. (12 floor above 00m, 2 floor under 00m). Under ground levels are under construction using slurry wall techinique. Building foundations are reinforced concrete piles. Metallic columns are attacched (welded) to steel armour from the reinforced pile before being placed down. Concrete is poured through the steel column up to -2 floor for the pile concrete and up to 0 floor inside the metalic column.

An special issue from this project is that because of the two underground levels and its construcion technique, the crane tower could not be anchored to any reinforced concrete foundation at a 00m level. It is needed to be fixed to a structural system atached to the beams and columns from 0 floor and -1 floor (-2 floor is a concrete slab).

Any experience for this kind of project? We already have a possible mounting plan, but it will be usufull to know prior experience from you.

Thanks a lot!

 

[CANPRO]

A framing plan of the area would be helpful, and maybe some info on your tower crane (what does the base connection looks like for a typical application?).

Without any more info, I can say two things: Make your beams extremely stiff - depending on the ratio between your base dimension and the height (usually large for a tower crane), a little bit of deflection at the base can lead to considerable lateral deflection at the top of the crane. Second thing, try to make all of the support points of equal stiffness (within reason) - different support stiffness might lead the crane to deflect laterally, perpendicular to the boom...which could induce some torsion in the tower.

 

[Wallache]

On one of our 5 floor wood over 2 floor parking/podium projects, the contractor used a weighted base tower crane and then shored down the levels to foundation. Doubt that would work for a free standing tower crane to 12 floors. Can you attach the crane at the upper floors?

 

[miguelandrade]

Hello friends,

Tower cranes are:

Liebherr 50LC working with 4 tower modules of 12m each.
Saez S52 working with several tower cranes of 8m and 12m.

Both tower cranes will be working with at 30m radius


I share:
a plan from the project where tower cranes positionS is shown.
a picture of a crane tower the same as ours mounted on a concrete foundation is attached.
Both tower crane specs

Thanks, if any other info will be usefull let me know!

 

[miguelandrade]

Plans from the project.

 

[miguelandrade]

Liebherr 50LC specs

 

[miguelandrade]

Saez S52 specs

 

[Agent666]

My usual experience is that the crane is still fixed to foundations at the basement and you simply provide a void through the suspended levels for the crane. Usually the crane is required for the basement construction as well?

The issue with attaching it to beams and columns is that these will be inherently more flexible than piles socketed into rock. This is an issue because 10mm of vertical beam deflection over say 2.5m wide crane equates to 200mm of Lateral deflection at 50m elevation. Not saying you can't do it, but definitely something to consider.

It's also a possibility to connect it to the building once you get over a certain height to provide stability.