Controling an earthquake:
In an earthquake-prone area if it is known that the strain is accumulating, the threat of earthquakes can be reduced by the following methods.
- A number of deep hole are drilled along a fault line in which stress has been detected. then water is pumped down into the holes. This water acts as a lubricant, s the fauted rcks sip smoothy in a series of small nondestructive earthquakes.
- Nuclear devices can be exploded along a fault plane which releiees stain by producing small earthquakes.
Earthquake resisting structures:
To build earthquake resisting structures, it is necessary t determine the probable intensity and magnitude of earthquake shocks in the area concerned. The history of the previous earthquakes and the knowledge of the local geology are of help in this connection. Some precautions are as follow:
- A study of past earthquakes indicates that the damage is usually much greater in structures founded on soft ground than on hard rocks. It is therefore advised, that jin seismic areas the structures should be founded on bed rock. If the same is not possible, reinforced concrete raft foundation should be given. During the passage of seismic waves, the structures built on raft foundation literally floats.
- Careful planning can ensure that the streets are wide in relation to the height of buildings. Many of the deaths caused during earthquakes are due to collapse of tall buildings into narrow streets.
- It has been found that rigid structures endure seismic shocks better than flexible ones, that is why steel framed and ferro-concrete structures generally survive severe shocks.
- Generally, construction of the taller structures should be avoided.
Related Article: How to protect from earthquakes