Drilling hole on structural slab

[gottemewrong]

Hello Palz

Im trying to have a new partition wall on a condo unit on the fifth floor, I have to drill on the floor slab 12 mm diameter and 4" depht apaced at 60 cm apart for my vertical reinforcement for CHB partition.. the structure is 28 storey high, no details for the structural design what so ever being purnished but thrugh inspection I found it a flat plate desind slab.

Any idea and sugestion is much appreciated.

thanks in advance

fratrowie

 

[JedClampett]

As long as you don't cut any reinforcing you should be fine. You can use non destructive methods such as X-rays or pilot holes to locate reinforcing and avoid cutting them with your holes. And even if you did cut some, the slab might be fine depending on the location of the cut bars, how many are cut and the conservatism of the original design. Unfortunately, you'll need drawings and calculations to figure that out.
As a caution, many high rises are built as post tensioned slabs, which adds a huge complexity to the problem.

 

[csd72]

JedClampett made some very good points.

Just to add on what he said. The reinforcing on the near side of a slab can often be located by a cover meter.

I you can see the edges of the slab you may be able to tell if it is a post-tensioned slab. If there are grouted pockets along one of the edges then it is post -tensioned if not then it probably isnt. Note that you will need to check all edges as only one end of the tendons will be grouted.

As far as cutting tendons, this is a definate no no. Specift that all holes are to be drilled by a regular percussion drill and that no diamond drilling is allowed. I have been told by reliable sources that percussion drills cant cut through the tendon steel.

This may also work for reinforcing.

csd

 

[civilperson]

Why not try a lesser depth (and lesser diameter), say 2 5/8" embed with epoxy adhesive like Hilti HIT 150? A bonding agent and lightly roughened surface will produce good adhesion and shear values for the concrete to concrete joint, thus lessening the need for reinforcing to withstand shear.

 

[JAE]

If you have a post-tensioned slab then you'd better not drill anywhere near the tendons.

You state that you don't have any structural details - I'd recommend you do everything you can to find the original plans prior to drilling.

 

[gottemewrong]

thanks to all!!


Well, I will start from your ideas and suggestion...In a week I think I will start my task.. again thanks a lot. More power.


Regards;

fratrowie