This is our August 2010 design newsletter. Today I’d like
to talk about earthquakes and how safe our buildings really are.
If you are one of the people who were screaming during the last
big shake this summer, read on! I hope you will feel a bit safer
during the next one. Also, you can post your reply to this newsletter
on my new
News corner, I’d like to share a glimpse of the
largest in history Solar
EXPO happening in Shanghai this year. I will be visiting this
EXPO this month and will share my findings from the solar world
in the next newsletter. Stay tuned!
up in Uzbekistan
and experiencing frequent earthquakes inside of a precast concrete
panel building was quite a frightening experience. The sound
of grinded rebar connecting concrete could wake you up in the middle
of the night at any time. But when architecture became my life,
I started realizing how very safe residential buildings can be,
well at least in California.
Read on to learn more!
KOHLWES principal / designer
SAFE ARE OUR BUILDINGS IN EARTHQUAKES?
another earthquake hit San Diego last month, it was an unforgettable
experience. It was not just because some members of my family were
helplessly screaming in horror and dropping to the floor. What was
more shocking to me was my calm reaction and my absence of fear.
What was I doing at that moment? I was staring at the buildings
in front of my windows as they (the buildings) were going in wave-like
motions, like the Pacific Ocean itself. It was mesmerizing and fascinating
to me! The structure was doing exactly what we were schematically
drawing in our structure classes calculating the forces and the
sizes of the members! The building was bouncing and moving like
a spring keeping us safe inside.
Do We Design For Earthquakes?
what happens when an earthquake hits our buildings, and how do we
(people in the construction industry) design buildings for seismic
events? I hope after reading this newsletter you will feel a bit
safer inside your home. Well, at least inside the newer homes that
are designed using the latest building codes which are constantly
updated after large earthquakes hit the US.
are several factors on how much damage your building can expect
in a larger earthquake: proximity to the earthquake fault
line, the type of soil your house is built on (available as a geotechnical
report for your land before your house was built, the softer the
soil, the more damage can be expected), the quality of construction
(avoid cheap, inexperienced home builders) and of course the structure
an earthquake strikes, deep and sandy soils can turn to liquid
by a process known as liquefaction, with disastrous consequences
for the buildings above.
will not go into all the details above, but will mention what
goes into designing your building’s structure. Structural
engineers calculate all the expected loads on your building
structure with precision. The sizes of each structural member
have to be calculated and spaced at the right distance. Every
member connection and every bolt has a designation, particular
strength and is used according to a different condition per
design. Each building, when in design, is looked at from different
perspectives applying different types of loads expected and
unexpected (but possible). An earthquake is one of these loads.
what I understand, buildings in California in general are designed
for 8.0 magnitude earthquakes, which is a rare occasion here.
The strongest magnitude earthquake registered in San Diego was
below 7. Besides, our structures are typically over-designed,
which means even if a magnitude 8.0 earthquake hits your building
it should be fine. Only if other factors mentioned above come
into play, may your building collapse.
is how Michael A. McNeff, S.E., president of McNeff
Engineering & Consulting Corp. answered my question
on how strong our buildings are designed here in California:
“...the building code doesn’t design to certain
Richter scale events, but rather postulates the worst expected
ground acceleration (earthquake) that would occur approximately
once every 2,000 years. It’s impossible to say what exact
magnitude this would be, but certainly on par with the great
earthquakes of modern times (e.g. San Francisco, Mexico City,
Northridge, Iran, etc.). Many of these were over 8.0.”
I hope knowing all this will make you feel
a bit safer from now on during our frequent shakes in San Diego.
Things To Remember
are some earthquake safety precautions on my personal list
that I can share:
• Stay away from the hot water pipes, gas pipes and
glass. This means: stay away from your kitchen,
bathrooms and large windows
if the glass is not tempered. (Tempered means it was treated
with heat to prevent it from shattering into sharp pieces.)
• If you see your ceiling is collapsing, run to the
opposite side of the room so the structural members (if they
should fall down) create a triangle over you.
• One of the safest places is to the side of your bed.
Don’t go under it, it maybe hard to get out later and
the bed’s legs may not be strong enough to withstand
the weight above it.
• Don’t use elevators to go down; you may get
stuck if the electricity gets cut off.
• Keep all your documents handy in case of fast evacuation.
• Make up a meeting place with your family in case you
get separated and the phones don’t work.
more on expected earthquakes on California HERE.
Francisco Earthquake of 1906
from May 1st to Oct 31st 2010, the Shanghai World Expo will be the
biggest event in its history, with 192 countries and 50 International
organizations having confirmed participation. 70 million visitors
are expected from both inland and abroad to attend this world event.
More than 20,000 cultural shows will be held during the Expo.
Themed "Better City, Better Life", the 2010 World Expo
Shanghai conveys a common wish of mankind for a better future and
better city life. Read more HERE.
for architectural changes to your property? Contact us HERE!
more news on similar subjects:
Steps To Shape Up Your Business Space!
of Business’ Environment As Branding Support In Services Marketing
Your Electric Bill Up To $300 a Year!
of Attraction or How To Select Your Wall Art
and After Images - 2009 Projects