Earthquakes

    Set Your Table for a Sweet and Sticky Earthquake Shake

Introduction

The purpouse of this experiment was to see which soil was the best side to side earthquake conducter. We had 4 soils and fake peanut butter suger cube houses. My hypothesis is that the bedrock will be the worst conductor and the gravel will be the best conductor

Materials

To build the shake houses

-Butcher paper or newspaper

-Damp cloth to wipe your hands on

-Sugar cubes (approximately 600)

-Bowl

-Spoon

-Peanut butter

-Scissors

To build the shake table

-Packing tape

-Coffee can lid,

-Marbles, or any small balls of the same size (1-2 dozen)

-Shallow box, like the lid on a board game box

-Tray

to make the soil trays

-Play-Doh®

-Flour (3 ½ cups)

-Salt (½ cup)

-Oil (3 tablespoons)

-Water (2 cups, boiling)

-Grape-Nuts cereal (1 box)

-Cornstarch (1 box)

-Water (approximately 4 cups)

-Bowls (2); for mixing Grape-Nuts with water, and cornstarch with water

-Spoon

-Fork

-Trays (4); any shallow nesting trays that are bigger than your test houses

to test the houses

-Stopwatch

-Lab notebook

-Camera (optional)

Procedure

Building the shake table

1. Cut off a strip of the packing tape and form it into a loop with the sticky part on the outside.
2. Attach the tape to the top of the coffee can lid and the bottom of one of the trays so that the top of the lid is stuck to the bottom of the tray.
3. Dump the marbles into the game box lid.
4. Set the tray with its attached coffee lid so that it is resting on top of the marbles. The lip of the lid should be resting on the marbles. This tray will hold your other trays as you perform each trial. Now you're ready to shake the game box side to side to create your P-waves. Continue with the rest of the steps first.

Building the test houses

1. You can build any shape of houses that you want, but keep in mind that you will need to build 12 of them, they should all be exactly the same, and they must fit inside your trays.
2. First, spread out some butcher paper or newspaper to make cleanup a little easier. Keep a cloth or bowl of water around to clean your hands if they get super gooey during the building. You should also make some clear space on the table or another counter for your completed houses.
3. Dump out some of your sugar cubes into a pile on the butcher paper or newspaper. You have a lot of sugar cubes and a lot of houses to build, so don't dump them all out at once.
4. Scoop out some peanut butter  into a bowl and put it next to the sugar cubes.
5. Now start dipping sides of the sugar cubes into the peanut butter and sticking them together. The sugar cubes are like little white bricks, and the peanut butter is like mortar. Build your first house on a section of paper that you can cut out when you are finished. Continue until you have created your first test house. Don't eat more than you build!
6. Cut out the paper around the test house and set it aside until you're ready to test.
7. Repeat steps 3-6 until you have 12 test houses that are built exactly the same and are all on their own pieces of butcher paper.              

Preparing your soil trays

1. You will be preparing four trays for testing models of four different soil types: bedrock, gravel, alluvium, and sand.
2. To prepare the bedrock model, fill one tray about half full of Play-Doh (either store-bought or homemade).  
3. To prepare the gravel model, pour dry Grape-Nuts cereal into another tray until it is about half full.
4. To prepare the alluvium model, mix about 2-3 cups of dry Grape-Nuts cereal with about 1 cup of water and pour the mixture into another tray until it is about half full.
5. To prepare the sand model, you will need a ratio of about two parts cornstarch to one part water. Put 3 cups of cornstarch in a bowl. Slowly add about 1 ½ cups of water to the cornstarch, mixing as you go with a fork or with your hands. You will know that you have the right consistency of the cornstarch mixture when it is firm enough to support a test house, but still liquid enough that you can press your finger slowly down into it.

Testing your houses

1. Now it's time to try this out! You finally get to shake your test houses on the four different soils.
2. Begin trial 1 with bedrock. Slide a test house and its paper gently onto the middle of the bedrock tray. Press the house down slightly into the test soil so that there is good contact between the test soil and the test house, and the test house does not slide around on top of the test soil during testing.
3. Place the prepared bedrock tray into the empty shake table tray. The bedrock tray should "nest" snugly into the empty tray in the shake table.
4. Have a helper time you shaking the box lid for 20 seconds. When you're ready to start, have the helper say, "Go!" and start a stopwatch.
5. Now shake or vibrate the game box lid from side to side very rapidly until 20 seconds have passed and your helper says, "Stop!". During the shaking, your hands should move from side to side no more than an inch or two, and you should avoid letting the tray bump the sides of the game box.
6. Take photographs for your display board, if desired.
7. Remove the prepared tray and the broken test house.
8. Repeat steps a-e for the three remaining soil types: gravel, alluvium, and sand. Be sure to record your results in your data table after each shaking test.
9. Repeat "Testing Your Shake Houses" steps 1-4 for two additional trials per soil type so that all 12 houses are tested. ecord the number of broken or fallen walls in your data table.                         

Data

Number of broken walls      Bedrock       Gravel      Alluvium     Sand

Trial 1                                         4                   4               4                4 

Trial 2                                         4                   4               4                4             

Trial 3                                         4                   4               4                4

Sum of trials                               3                   3                3               3

Average of trials                         4                   4                4               4

Conclusion  

 My hypothesis was correct because the house in the gravel fell almost instantly but the bedrock house stood a little longer. If I did this again I would Build a bigger house because when I Built a small house it didn't fall and when I built too big of a house it just collapsed. this relates to how when engineers build more compact house with stronger materials on a firm foundation they withstand better in an earthquake. This experiment is a perfect stimulation of a real life earthquake.