Method 10
Concrete slab demolition in Abu Dhabi, Dubai & Al Ain
Removal of suspended and ground floor slabs by cutting into planned sections and lifting them out. Quieter, faster and far less disruptive than breaking a slab in place.
What it is
When to specify slab demolition
Slab demolition means taking out a floor, either a section of it for a new opening or the whole thing during a structural alteration. Done with breakers it is loud, dusty, slow and hard on everything around it. Done by cutting into sections and lifting them out, it is a controlled operation that fits inside a live programme.
The two questions that decide a slab demolition job are what is holding the slab up and how the pieces are coming out. Neither is answered by looking at the slab. A suspended slab redistributes load once you start cutting, so the propping and the cutting sequence come from a structural engineer before we mobilise. The removal route decides the section sizes.
Typical work is forming atrium and stair openings in existing floor plates, taking out slabs above basements during refurbishment, and removing ground slabs where new foundations or drainage runs beneath. Most of it happens in buildings that are still being used.
Applications
What we use it for
Atrium and void openings
Sections cut from a suspended floor plate to create double-height space or a new light well.
New stair and lift openings
Slab removed to form the shaft, cut to the exact opening with square edges ready for the new structure.
Structural refurbishment
Whole floors removed during strip-out where the frame is retained and the slabs replaced.
Ground slab removal
Floor slabs taken out for new foundations, drainage, pits or level changes in industrial buildings.
Basement and podium works
Slabs above occupied or sensitive spaces removed where breaking is not permitted.
Plant room alterations
Openings formed for equipment replacement where new plant will not pass through existing access.
Sequence
How the job runs
Engineer's design and lift plan
Propping, sequence and section weights confirmed before pricing. Crane or lifting arrangement agreed with the removal route.
Prop and scan
Temporary works installed to the design, then the full cut zone scanned for reinforcement and post-tension cables.
Cut into sections
Slab cut by floor saw, wall saw or wire depending on thickness and access, into pieces within lifting capacity.
Lift, clear and hand back
Each section restrained, lifted to a prepared laydown area, loaded out and the opening left dressed and safe.
Site control
Section weight is the number that matters
Concrete weighs roughly 2.4 tonnes per cubic metre. A slab section two metres square at 250 mm thick is around 2.4 tonnes, which surprises people every time. Every slab demolition we quote includes a calculated weight for each section, matched against the crane or lifting equipment actually available on site.
Getting this wrong is the most common failure in slab removal. A section cut larger than the lifting capacity has to be cut again in mid-air or dropped, and neither of those is a plan. The section sizes therefore come from the lifting capacity and the access route backwards, not from what is convenient to cut.
We also agree the laydown area before the first cut. A five tonne slab section sitting on a suspended floor that was not designed to carry a point load of that size is a new structural problem, not a solved one.
Questions