Slab in construction - Classification, Purpose , Uses , One way and Two way Slabs

The word “slab” is a commonly and often used term in construction. In the context of civil engineering, it is referred to concrete slab. So in this article, I will discuss about concrete slab.

Slab in construction

Now we will see What is a slab?

It is a flat piece of concrete, put on the walls or columns of a structure which is typically square or rectangle in shape where are constructed to provide flat surface such as as floor slab, ceilings slab, slab roof etc.

Mostly slabs are horizontal and have smaller depth as compared to is span.

Purposes and uses of slab

• They provide Flat surface.
• Used to distribute loads in supported beams, columns, walls etc
• Used in buildings, bridges etc.

Classification Of Slab:

Slabs are been divided into two types which is been differentiated on the basis of there aspect ratios and support system. They are

• One way slab
• Two way slab

One way slab definition

A slab when supported by beams or parallel walls on two opposite sides the slab is known as one way slab. In easy terms the length of slab is longer than the breadth of the slab whose ratio is ≥ 2.

1. The load in one way slab is always carried out along one direction.    
2. As per IS Codes, In one way slab, the ratio of longer span (L) to shorter span (b) is equal or greater than 2. i.e                                                                                                                            
3. longer Span/ Shorter Span = L/b ≥ 2

One Way Slab

We can take the reference of the above image and can easily figure that the length of the slab is longer than the breadth and should have L/b ≥ 2, so we can consider it as one way slab.

• Note- In one way slab always the main bars are provided in shorter span direction.

Two way slab definition

The slab which is supported by beams or walls on all four sides, is known as two way slab. The breadth is longer than the span.

• In two way slab the loads are carried out along both shorter & longer directions.                            
• As per IS Codes, the ratio of longer span(L) to shorter span(b) is always less than 2. 
• Longer span/Shorter span < 2. 

Two way slab

Difference Between One Way Slab And Two Way Slab: