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FAQ on earthquake resistant construction - your technical comments invited

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Hello Seaint members,
 
As an Indian, affected by the latest devastating earthquake, I would like to bring awareness about "earthquake resistant construction" to our fellow Indians in particular and also to the citizens of other countries. In this context, I have prepared a small session of 'Frequently asked questions & answers'. May I request our learned colleagues to suggest me the improvements / corrections / comments on this FAQ, if any.
 
Thanking you, in anticipation of  your constructive comments
 
BHAGAVAN
 
 
 
EARTHQUAKE RESISTANT CONSTRUCTION (ERC) 
 
It is a session of FAQ on ERC
 
 
* Is it possible to predict earthquakes?
No!
 
* Is it Possible to prevent earthquakes?
No!
 
* Are earthquakes destructive and devastating?
Yes! Because they destroy infrastructure. Hence, they are devastating.
 
* Do earthquakes kill people?
No - not directly!
 
* But, how people are killed during earthquakes?
Collapse of building structures in which they live, during the earthquake kills people. Hence, the real culprits are our construction practices and poor quality of construction. The conventional buildings instantly collapse without any warnings, during the unpredictable and sudden earthquakes.
 
* Is it possible to build totally earthquake proof building structure?
-It is not feasible and economical to design and construct totally earthquake proof building structures, particularly to withstand very severe earthquakes of magnitude above 8.0 (Richter Scale)
- But it is very much possible to design and construct earthquake resistant building structures, though they may suffer huge damage for severe earthquakes, which will not kill people
 
*What is the best building construction practice to resist earthquakes?
Shear wall concept!
 
* What is shear wall concept in building construction practice?
In this concept the walls are not only designed to resist gravity / vertical loads (due to its self weight and other living / moving loads), but they are also designed for lateral loads of earthquakes / cyclones. The walls are structurally integrated with roofs / floors (diaphragms) and other lateral walls running across at right angles.
 
* How is it structurally superior to the conventional construction practices of load bearing masonry structures and / or Reinforced Cement Concrete (RCC) framed structure(of concrete beams, columns and slabs)?
- The load bearing masonry is very brittle material. Due to different kinds of stresses such as shear, tension, torsion, etc., caused by the earthquakes, the conventional unreinforced masonry collapses instantly during the unpredictable and sudden earthquakes! 
- The RCC framed structures are slender, when compared to shear wall concept of box like three-dimensional structures. Though it is possible to design the earthquake resistant RCC frame,  it requires extraordinary skills at design and construction levels, which can not be anticipated in all constructions projects!
- On the other hand even moderately designed shear wall structures are comparatively ductile. In safety terms it means that, during earthquakes they will not suddenly collapse causing death of people. They give enough indicative warnings such as widening structural cracks, yielding rods, etc., offering most precious moments for people to run out off structures, before they totally collapse.