Why soil is provided underneath the footing?
In this civil engineering article, you will know the reasons for laying sand underneath the PCC foundation.
Given below, the detail reasons :-
Maintain Uniformity: When the foundation soil contains lots of clay and silt contents with water, the river sand is utilized to maintain consistency for foundation bed specifically for PCC bed.
Resist Earthquake: When the footing is arranged directly on the rock bed, even a negligible judicious amount of vibration on the earth at the time of earthquake can lead to the failure of the structure. The purpose of utilizing the sand is to get rid of earthquake.
Reduce the fragile spot: Although the anti-termite is applied in foundation, some fragile points may exist for penetration of termite. To get rid of this issue, sand is utilized with anti-termite treatment underneath the foundation.
Why PCC bed is used ?
The objective of applying PCC bed is to maintain consistency to the foundation bed so that the termite can’t enter to the structure.
If the footing is arranged directly over the unsteady sand, the collapsing may occur because of harsh weather condition. The soil may widespread or turns out to be unsettled throughout rainy seasons and as a result the structure can collapse completely.
To learn complete process, watch the following video tutorial.
Video Source: Civil Engineer Deepak Kumar