Is it advisable to do core cutting in slab. After complition of civil work we realised that we have to cut 300mm bore (core) to transfer material from 4th floor to 3rd floor. Our slab thickness is 500mm.
300mm dia hole, no problem... 500mm thick slab, little problem, but not a big problem. BE CERTAIN that all structural elements are ACCURATELY LOCATED AND MARKED! BE CERTAIN that all utilities inside slab are ACCURATELY LOCATED AND MARKED! You will need a contractor to do this, it is sort of a messy, noisy job. He can give you a lot of advice to prepare.
Don't forget... the core (piece removed) will fall thru, landing on the third floor. A piece of concrete that large will make a pretty big bang when it hits!
- a crash deck just under the core-drilled floor will stop damage to the floor beneath
- if the core is close to a column, you need to get the engineer to okay this as you will probably be cutting through some important reinforcement. 300mm will be cutting through at least 2 main bars in any one layer of reinforcement
- if you are not close to a column or beam then you will still need to ask the engineer since he has probably allowed for small diameter holes in his specification (less than 100mm diameter for example)
- 500mm slab sounds very thick and may be a transfer slab, in which case you this is another good reason to ask the engineer
You can also drill from the bottom, is a lot cleaner and can be done without creating a mess with the dirty water. (re: Hilty) And the cut piece stays in the core drill cylinder.
Make sure you check location of core drilling, try not to cut any of the steel, or you have to check the design for loss of reinforcement. The slab thickness is too large. Never seen this on the job. Please make sure your structural engineer takes a good look!
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