The purpose of this experiment was to determine which building shape
would best withstand an earthquake.
I became interested in this idea when an earthquake occurred in the
state of Washington.
The information gained from this experiment could be used by building
designers and engineers to know which building shape to build in an earthquake
zone versus a non-earthquake zone.
My hypothesis is that the dome shaped building would withstand an earthquake
for the longest.
I base my hypothesis on World Bookís Young Scientistís Encyclopedia
on Construction and Machines, which states, "It is most useful because
it holds itself up."
The constants in this study were:
The manipulated variable was the shape of the building.
The magnitude of the simulated earthquake
The materials used to build each building
The earthquake simulator used
The distance each toothpick is stuck into the clay
The diameter of each clay ball
The placement of each building on the earthquake simulator
The responding variable was the time it took for the different buildings
To measure the responding variable I will measure the time the building
stayed up before collapsing in seconds.
||Size 33 Rubber Bands
||4D 3.8 cm Nails
||41 cm by 7 cm Pine Board
||25 cm Peg Board
|| 35 cm by 7 cm Pine Board
Build the Earthquake Simulator
1. Tie a rubber band to each corner of the pegboard by putting it part
way down the hole and bringing it back through the loop in the rubber band.
Each rubber band should be in the closest hole to the corner. Make sure
it is pulled tight.
2. Connect these 4 pieces of wood together by putting two nails into
each end of the wood. Two should be in each corner with one directly above
3. Using the hammer put four nails on top of the fir wood boards, with
two on each side, cm from each corner. These should be about 1 cm deep.
4. Attach the rubber bands and the pegboard together by looping the
rubber bands onto each nail.
Construct the Buildings
5. Make a square with the toothpicks by connecting them with 2 cm diameter
spheres of modeling clay.
5. Put a toothpick in the top of each ball. They should be forming
a 90° angle with the toothpicks on the bottom row.
7. Repeat step 5. Then place this square on top of the toothpicks that
are sticking up. This is now a cube.
8. Repeat steps 5-7 two more times.
9. Make three more cubes using steps 5-7.
10. Now put toothpicks in the top of each clay ball on the four higher
ones as shown in step 6.
11. Now make squares and place them on top of these toothpicks.
12. Repeat step 5.
13. Put one toothpick in each clay ball so that they can be connected
at the top with another clay ball.
14. Connect each toothpick at the top with a clay ball. Each side should
be a triangle.
15. Make a hexagon with toothpicks and connect them with clay.
16. Make triangles coming up out of every other 2 clay balls.
17. Connect the top of the triangles so that they form another triangle
18. Repeat steps15-17 twice.
Conducting the Experiment
19. Place the first cube in the center of the earthquake simulator.
20. Pull the peg-board back to the edge of the 35 cm.
21. When you let go, begin the stopwatch.
22. Continue pulling back the peg-board until the building collapses.
When it collapses stop the stop watch. If the building does not collapse
after 5 minutes, stop the stopwatch.
23. Record the time in a data table.
24. Repeat steps 19-23 for each of the cubes.
25. Repeat steps 19-23 for all of the tall rectangles.
26. Repeat steps 19-23 for all of the pyramids.
27. Repeat steps 19-23 for all of the domes.
The original purpose of this experiment was to determine which building
shape best withstands an earthquake.
The results of the experiment were that the dome and the pyramid were
able to withstand the earthquake the longest. They never fell after 300
seconds. The cube stayed standing for about seven seconds. The tall rectangle
did not stand over a second in any of the three trials.
See the table and graph below.
View my Data and Graphs
My hypothesis was that the dome would withstand an earthquake for the
The results indicate that this hypothesis should be accepted.
Because of the results of this experiment, I wonder if the taller that
a tall rectangular building is, the less amount of time that it takes before
it collapses in an earthquake.
If I were to conduct this project again I would make my clay balls smaller
so that the dome and the pyramid would eventually fall over. Also I would
build my earthquake simulator larger so that I could pull the pegboard
back farther and increase the magnitude of the "earthquake". I would also
do something to alter the design so that the tall rectangle and cube would
better withstand the simulated earthquake. I would also do more trials.
Safety is important to everyone. Earthquakes destroy buildings and the
homes of people. They cause tsunamis, fires, chemical spills, landslides,
and several other disasters. Earthquakes are very dangerous. Buildings
must be earthquake resistant so that our lives will be in the least danger
According to World Book Encyclopedia, an earthquake is, "A shaking of
the ground caused by the sudden breaking and shifting of the earthís rocky
outer shell." Earthquakes can be very powerful or, they can be so small
that they canít be detected by a human being. Large earthquakes are usually
followed by smaller ones called aftershocks. Aftershocks are usually a
lot smaller than the main earthquake.
Most scientists agree with a theory called plate tectonics. They believe
that several plates are floating on the mantle of the earth. When these
plates collide, it causes stress and an earthquake takes place.
Harry Fielding Reid studied the San Andreas Fault and formed a new theory.
He theorized that the cause of an earthquake was not close to the focus,
or center of the earthquake. He said that forces that are very distant
build up over hundreds of years. When the earth cannot resist this force
it gives way. This theory is called the "elastic rebound theory."
"Body" waves usually cause the most seismic damage. There are two
types of body waves. There are the compressional waves and shear
waves. Compressional waves are when the rock is compressed and expanded.
Shear waves are when the rock shakes back and forth. "Surface" waves are
long and slow. The two kinds of surface waves are Love waves and Rayleigh
waves. Love waves have a side-to-side movement. Rayleigh waves roll like
the waves of an ocean.
To determine the strength and location of an earthquake, scientists use
a seismograph. A seismograph is a machine that has little sensors called
seismometers. These detect the shakings of the ground that are sometimes
very far away. They can detect movements as little as a billionth of a
meter. Scientists called seismologists measure the ground movement in three
directions: up-down, north-south, and east-west. The record of a wave is
called a seismogram.
The intensity of an earthquake is usually measured on a 12-point scale
called the Modified Mercalli Scale. The magnitude of an earthquake is measured
on the Richterís scale. This is a measure of the strength of its source,
or focus. On this scale, every increase of one number means that
the earthquake has 32 times more energy released by the quake. A seven
on the Richterís scale is severe, while an eight is devastating. A two
can only be detected by a seismometer. Another scale is called the Moment
Magnitude Scale. This is the most accurate of the scales. It measures the
total damage done by an earthquake.
EARTHQUAKE PROOFING BUILDINGS
Geologists look for and do research on safe places to build. They say
that the best places to build structures are away from an earthquake zone.
Also it is best not to build in mud or soft dirt. This could cause a building
to sink quickly.
Architects and engineers have also developed several building types.
They include cross bracing, shear core, base insulator, and shear wall
buildings. Cross bracing has braces in each side and on each level, which
forms a cross. This reinforces the walls of a building. Shear core buildings
have a square core in the middle that runs from top to bottom. This helps
to resist the rocking that an earthquake has. The base insulator has an
insulator built between the foundation and the walls of a building. The
insulator is made from steel and synthetic rubber. Moats that are built
around a building allow a building to sway. Flexible framework also helps
the building to sway.
Safety precautions are very important during an earthquake. People should
not go outside until the shaking is over. They should crouch under a desk
or crawl under a bed or chair. If you are not able to get under one of
these, you should stand under a doorway.
Earthquakes are a major natural disaster. Although they almost never kill
people directly, they are very dangerous. Scientists are studying seismic
waves in hope of finding a way to predict them in advance. Engineers are
also trying to determine which building designs are the best in earthquake
"Earthquake." Microsoft Encarta Encyclopedia Deluxe. 2001.
"Earthquakes." The World Book Encyclopedia of Science, The Planet Earth.
"Earthquake." Websterís Third New International Dictionary Unabridged.
"General Quake Information." November 21, 2001. http://quak.wr.usgs.gov/info/basics.html
McNally, Karen C. "Earthquake." The World Book Encyclopedia.
Simon, Seymour. Earthquakes. New York: Morrow Junior Books, 1991.
"The Strength of a Dome." World Bookís Young Scientist. Volume 9. 1997.
"Understanding Earthquakes." November 12, 2001.
This science project could not have been completed without the help
and advice given to me by several people. I would like to thank each one
of them for their help.
My dad helped me build the earthquake simulator by cutting the wood
to the right sizes with the electric saw. He also gave me several pieces
of advice for building the buildings.
My mom was very supportive and drove me to before school work times.
She also picked me up after the after school classes.
My friend Erik for giving me the wood to build my earthquake simulator.
He also was able to give me advice on my project since he did one similar
Mrs. Helms gave me advice and encouragement when I was having trouble with
Mr. Newkirk for giving advice when I was struggling and on my journal and
report and my project board.
Top of page
Menu of 2001-2002 Science Projects
Back to the Selah Homepage