ballast roll in house construction

The most commonly used ingredient in concrete, both by volume or by weight, is gravel. Ballast density, water absorption capacity, size, measurement and external surface form are some of the important properties that affect the properties of concrete made from it, and the strength of concrete in particular. In this way the ballast affects the construction of the house.


ballast



The ballast should be of this type

The ballast should be of sufficient strength and as far as possible of granite stone and approximately cubical.

Instead of using ballast of only one size in concrete, 20 mm in large size and 10 mm in small size should be mixed in proper ratio (approximately 60:40 to 70:30).

By mixing both types of ballast, the smaller ballast settles in the middle of the larger ballast, due to which we get better packing of particles in concrete. In this way the concrete becomes solid and waterproof, which not only increases the life of construction but also reduces the extra cost of cement.

Like sand, ballast/gravel should not contain any degrading chemicals, as they react with cement to reduce strength and durability.

What is a bad ballast ?

Symptoms of bad ballast

The ballast should be made of porous and low strength stone.

All the particles in the ballast should be of approximately the same size.

Long and flat ballast particles reduce the strength of concrete and also increase the cost of cement.

If the length of the ballast particles is twice or more than their width, then by applying pressure on the ballast, it will break easily and the strength of the concrete made from it will also be reduced.