RESISTANT CONSTRUCTION (ERC)
It is a
session of FAQ on ERC
* Do earthquakes kill
No - not
depends on how you define directly. A person could be next to a fault
when it opens, thereby falling into the fault and dying either by the fall or
* 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.
Agreed, you also have the stupid people who go
back into buildings that leaning 20+ degrees to get
* 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)
correct answer is, "You could but you wouldn't want to pay for it".
Cheyenne Mountain, site of the United States' air defense command (or some
such) is built to withstand 9.0+ earthquakes, nuclear bombs and chemical and
biological attacks. It is built on giant springs to withstand the
earthquakes. While Cheyenne Mountain is not practical for other
uses, the Transamerica Tower in San Francisco uses a similar methodology with
its springs and is a great example of uses active techniques to
"earthquake-proof" a building.
- 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
Hence, the current change in US design
*What is the best
building construction practice to resist earthquakes?
Shear wall concept!
Nope, WOOD. It's very flexible. IF
DESIGNED RIGHT, it doesn't even have to absorb the energy of the
earthquake. However, their are other limits to wood
* What is shear wall
concept in building construction practice?
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.