Table of Contents
In which part of a concrete slab and raft is reinforcement placed?
edge beams
Steel reinforcement is placed into the edge beams. The steel can’t be close to the ground or it will rust and fail – so concreters use plastic supports called ‘bar chairs’ to hold the steel away from the ground.
What is the standard thickness of concrete for a flat slab raft?
The Raft Slab: In fact, a lot of builders refer to this type of slab as a floating slab. This slab is usually 100mm thick with thickened edges varying between 300mm and up to 700mm deep. Throughout the slab there are also stiffening beams which are 300mm wide and vary in depth up to 700mm.
What is slab beam raft foundation?
Slab beam raft This type of raft foundation is typically used where there are unequally-distributed column loads. Reinforced concrete or steel columns are positioned on intersections of reinforced concrete ground beams, which add the required stiffness to the slab.
What is a raft slab foundation?
A raft slab is a concrete slab that contains slab thickening in areas to create beams that give more strength and assists with distributing the load in an even fashion. It is a common type of foundation for building new properties in Australia.
How do you calculate reinforcement for a slab?
Steps to calculate the Reinforcement required for Slab:-
- Deduct the cover for finding length of bar.
- Evaluate the length of the distribution bar.
- Calculate the Value of ‘D’ (Depth of slab- Top cover- Bottom cover)
- Find out the No. of Bars.
- Compute the Total wt of steel required for slab reinforcement.
How do you choose reinforcement of a slab?
Thickness of the slab is decided based on span to depth ratio specified in IS456-2000. Minimum reinforcement is 0.12% for HYSD bars and 0.15% for mild steel bars. The diameter of bar generally used in slabs are: 6 mm, 8 mm, 10 mm, 12mm and 16mm.
How is slab reinforcement calculated?
How do you calculate reinforcement in slab?
Steel Quantity Calculation Formula = (total length – clear cover)/center to center spacing + 1 main bar, = (5000 – (25+25))/100 + 1, = 4950 divided by 100 + 1, = 51 bars., distribution bar = (2000 – (25+25))/125 + 1, = 1950 divided by 125 + 1, = 17 bars.
How much steel is required for slab?
Ratio of Steel required to Cement Concrete
| Different Parts of the Building | Requirement of Steel TMT Bars in Kg |
|---|---|
| Bases | 90-130 |
| Floor Slabs | 80-120 |
| One way Slabs | 75-125 |
| Two way Slabs | 67-135 |