Download Structural Engineering Presentation

SEISMIC OUTREACH
K’NEX STRUCTURE COMPETITION
UNIVERSITY OF CALIFORNIA, SAN DIEGO
SOCIETY OF CIVIL AND STRUCTURAL ENGINEERS
Introduction
What is an Engineer?
A person who applies scientific principles to design, construct, and understand almost
all objects used by people in the world (engines, cars, bridges, machines, etc.)
What do Structural Engineers do?
Structural Engineers design buildings, bridges, dams, cars, helicopters, airplanes,
satellites, off-shore platforms, ships and all other facilities required to sustain loads
from various sources- air pressure, gravity, wind, waves, snow, impact, earthquakes,
temperatures, vibrations, etc.
Part 1: Earthquake Phenomena
Faults, Ground Motion, Measures
Tectonic Plates
Tectonic plates - “pieces” of the earth that float on its
liquid, molten core of magma.
Video - how the continents moved around over Earth’s
long history due to the floating of the tectonic plates.
Continental Drift.w mv
Fault Types
A fault is where two tectonic
plates (or continents) meet.
Earthquakes happen when
two tectonic plates rub
against each other.
San Andreas Fault
Pictures: http://www.ngdc.noaa.gov
http://www.sms-tsunami-warning.com/pages/fault-lines#.Vg3hUPlViko
http://www.iris.washington.edu/seismic/events/faults.html
Seismic Waves
Two types of waves:
1. P waves – causes
horizontal motion of
the earth
(compression),
travels quickly
2. S waves – causes
vertical motion of the
earth, carries more
energy, thus causing
more damage
http://www.lamit.ro/sistem-avertizare-cutremur.htm
Volunteer Demo!
Ground Motion: Intensity and Magnitude
• Magnitude: a measure of the amount of energy that is
released from an earthquake.
A magnitude of an
earthquake is the same no matter where you are.
• Intensity: a measure of the severity of an earthquake
depending on the distance from the epicenter. Intensity
changes due to the location
• Difference between magnitude and intensity: some spots
may “feel” an earthquake more than others not necessarily
because of how far away it is from the center (or
epicenter), but because of the soil it is on, what fault it is,
and many other factors.
(after Mavroeidis and Papageorgiou )
Earthquake Damage
Real Cases and Reality of Problems
Societal Impact
Dangers that an earthquake poses to a city
•Power lines fall and electricity goes out.
•Phone lines fall so phones don’t work.
•Water and sewage pipes break, and sometimes
sewage can get into water sources
•Gas pipes break, causing fires (like San
Francisco Earthquake). And if water pipes
break, fire trucks can’t use fire hydrants.
•Roads, bridges, and tunnels are ruined so
emergency vehicles can’t get to people who
need help.
Earthquake Damage
Kobe Earthquake 1995 (M6.7) 5,500 deaths
Video - man who is inside a skyscraper
building during the Kobe Earthquake.
The man is a white blob in the lower
right corner.
*Video on next slide
Earthquake Damage: Recent Cases
Feb 2010 Chile (M8.8)
Over 1 million homeless.
700 deaths.
http://www.about-knowledge.com/chile-earthquake-facts/
http://www.buzzybloggers.com/wp-content/uploads/2010/01/haiti-earthquake-2.jpg
Jan 2010 Haiti Earthquake (M7.0)
92,000 deaths.
300,000 injured.
1 million homeless.
http://en.wikipedia.org/wiki/2010_Haiti_earthquake
http://www.nytimes.com/2010/02/28/world/americas/28chile.html
Earthquake Damage: Recent Cases
March 2011 Japan (M8.9)
Over 18,000 deaths
Caused a 23-foot tsunami
http://www.guardian.co.uk/world/2011/mar/21/japan-earthquakedeath-toll-18000
http://www.boston.com/bigpicture/2011/03/massive_earthquake_hits_japan.html
Earthquake Damage: Near home!
Baja California (M7.2)
April 2010 – Easter Sunday
Epicenter in Mexico, affected two
countries
Hit 300 mi radius (hit Calexico hard)
Minimal damage and casualties
http://abcnews.go.com/WN/earthquake-hits-baja-california-easter-sundaydamage-light/story?id=10291558
Structural Engineering
Challenge: Solving the Problems
What do Structural Engineers Do?

Design the “skeleton” of the structure to increase safety by
resisting forces that they are exposed to which include:
 Gravity, “dead” load, “live” loads (people, furniture, cars)
 Lateral Loads (forces that hit from the sides)
 Wind
 Earthquakes!!!
Uncalculated forces from wind made the Tacoma
bridge collapse (built and destroyed in 1940).
How Structural Engineers Plan for
Disaster
Research: Mid-rise Building made from Reinforced
Concrete
• 7-story concrete tower that was on a real-life shake
table
• The building was only for testing and was destroyed
after this earthquake simulation
•This shake table is currently the worlds largest (in terms
of area), and is actually located here in San Diego
*Video on next slide
How Structural Engineers Plan for
Disaster
Research: Two-Story Wood Frame House
•Earthquake simulations on a shake table at UCSD
• Houses only built for testing purposes
Outside of House
Inside Room of House
Structural Engineering
Considerations for building towards safety
Challenge: Forces
Structures experience
forces from many things:
• People (Live Load)
• Building’s weight (Dead
Load)
•Nature such as wind and
earthquakes
•Etc.
Demo!
K’NEX Education
Structure Components: Beams
EERI, University of Notre Dame

Beam

Part of structure that
span between columns
and hold up the floors
Load is transferred from
the floor to the beams
into the columns and
down to the foundation
Demo!
Foundation
Structure Components: Columns
EERI, University of Notre Dame
Column


Part of structure that
support the building
(gravity loads)
Slender columns buckling
Demo!
Foundation
Structural components: Bracing
•Helps give strength to structure
•Positioning helps different
scenarios of “loads” and could
help with money budget
Arnold, C. and Reitherman, R., Building Configuration and Seismic Design, Wiley, 1982
Demo!
Connections
Important to keep
structure together in
“breaks” (steel
connections are
better than tape)
Pictures: C.M. Uang
Part 2: K’NEX Competition
Testing your knowledge!
Project Scenario
A rich land owner is looking for the best design of a building
in downtown San Diego near an active fault. Your goal is to
make a model of an appealing, original, and economical
building with lots of floor space out of K’NEX.
You will be placed in a Design-Build team of 4-6 to compete
to win for the best design. Awards will be given to teams
who do the best in certain areas.
The 4 Types of People Involved
UCSD Students play
1. “THE OWNER” – Judge for best design; Provides money
YOU in teams of students play all of the following
2. “THE ARCHITECT” – Designs the overall shape and “skin” of the
building for the Owner; wants the building to be beautiful,
appealing, original, and creative
3. “THE ENGINEER” – Designs the “skeleton” to hold up the “skin.”
wants to strategically design the building to survive a major
earthquake
4. “THE CONTRACTOR” – Builds what the Architect and Engineer
have designed for the Owner; wants to build in a timely
manner and on budget
NOTE: Every student in a group helps play each role. One role is
NOT assigned per one person. Every one helps with everything!
Architectural Drawing



Make the building look appealing and creative!
Colorful 3-D or multiple view 2-D Drawings
Include details such as Landscape (Plants, trees),
windows, doors, building signs, balconies, people
Construction Drawings




Include the
measurements of the
width, height, and
length
Provide multiple views
(different floors and
sides)
Be clear - Anyone
should be able to
build your design from
your construction
drawings
Use pens and rulers
Structural Engineering

Award Categories
Prizes and Certificates that will be given:
• Architectural Award - Best architectural rendering;
most appealing and original
• Construction Award - Best construction drawings;
most clear and detailed with best interview
• Structural Engineering Award – Best owners’
performance index of building that remains standing
Thank you! Questions?