Earthquake Safe Construction Guidelines

By: Haseeb Jamal / On: Nov 22, 2017 / Construction

By constructing houses and public buildings safe, 80% to 90% of loss can be reduced. Because
```
Disaster risk = Hazard * Vulnerability.
```
If Vulnerability is reduced, risk of disaster will decrease.
Prediction of earthquake only saves human losses not economic losses due to collapse.
Most of earthquake occurs in ocean.
Earthquake of Magnitude 6 evolves energy that is equal to 1 Hiroshima atomic bomb.
Magnitude 7 ==> 100x Energy evolved = 1 Hiroshima atomic bomb.
Magnitude 8 ==> 100 x 100 Hiroshima atomic bomb.
Earth is not consistent but its made up of plates.
- Each moves independently.
- Plates are called tectonic plates.
- Earthquake occur due to movement of tectonic plates and their head on collision.

Focus:

Deep in earth crust. 5 to 6 - 70 to 80 km depth.
More depth, less will be disaster as more is absorbed inside.
Projection of focus on earth surface is called epicentre.
Equivalent Energy is transferred through waves causing vibrations in structure.
Foundation also moves to and fro. If foundation is made stable, structure will be safe. For example if beams are provided on foundation and structure moves on the beams.
Walls and Columns are the most important by Earthquake point of view.
About 1500 tones of steel can be saved in a 60 storey building due to only one level difference of seismic zone.
90% of economy losses and 90% of human losses are due to the collapse of buildings.
Earthquake resistant building is one which does not collapse even if it has irreparable cracks.

Design span of buildings

Nuclear power plants-> 2500 years.
Dams and Bridges-> 500 years.
Houses-> 50 years.
Not even small cracks should occur in Nuclear power plants because implications are very high i:e, life safety levels are not common in each type of structure.
2% of total cost can save a building from earthquake.

Dhajji: Timber frames and bracing. To make earthquake resistant mortar take 1 bag of cement + 3 wheel barrows of sand. The mortar should be used within 1 hr.