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Amount of Time Compacted Soil in Layers
Holds Back Water |
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Researched by PURPOSE
The purpose of this experiment was to determine the effect of dirt compaction on the ability of dirt to hold water in a simulated levee.
I became interested in this idea when I read in the newspaper that New Orleans had been flooded and destroyed because a levee had broken.
The information gained from this experiment could protect people from getting their homes destroyed and being killed by floods because levees weren’t compacted in layers enough. Lots of people would care, especially engineers trying to build or protect people with levees.
HYPOTHESIS
My first hypothesis was that the more compacted layers there were, the longer it would hold back water.
I based my hypothesis on the fact that earthen dams and levees are usually built layer by layer with compaction of each layer before the next one is added.
The constants in this study were:
• Width of PVC
pipe
• Length of PVC pipe
• Amount of water put in PVC pipe
• Type of water put in PVC pipe
• Amount of dirt put in PVC pipe
• Type of dirt put in PVC pipe
• Temperature where testing
• Time brick compacted dirt
• Length of PVC pipe
• Amount of water put in PVC pipe
• Type of water put in PVC pipe
• Amount of dirt put in PVC pipe
• Type of dirt put in PVC pipe
• Temperature where testing
• Time brick compacted dirt
The manipulated variable was the number of layers that were compacted.
The responding variable was the amount of time it took before the dirt plug broke.
To measure the responding variables, I used a stopwatch and started it when I put the water in and stopped it when plug broke.
MATERIALS
| QUANTITY | ITEM DESCRIPTION |
| 1 |
2in (5cm) PVC pipe 30.5cm long |
| 1 |
2in (5cm) PVC pipe 133cm long |
| 1 |
2in (5cm) PVC pipe valve |
| Tap Water | |
| 1 |
Wooden Compactor (5cm circle attached to wood handle) |
| 1 |
16.78 kilogram brick |
| 1 |
Stop Watch |
| 1 |
2in (5cm) PVC pipe elbow |
| 1 |
¼cup (59millilitiers) measuring |
| 1 |
Bucket of native soil consisting of clay |
PROCEDURES
1. Build system
a. Connect the
133cm in length of PVC pipe to the 2in PVC pipe elbow
b. Connect PVC pipe valve to the elbow
c. Build plugs
b. Connect PVC pipe valve to the elbow
c. Build plugs
i. Put 473ml of
dirt in the 30.5cm length of 2in (5cm) PVC pipe
ii. Place compactor in PVC pipe on dirt then place a 16.78kg brick for 4 seconds on the circle to compact the dirt.
iii. Repeat steps i. - ii. until an 8 layer plug is created with 8 compactions
iv. Repeat steps i. - iii. until 5 plugs are created
v. Repeat steps i. – iv., reducing layers by half and doubling the time the brick sits on the circle compactor
ii. Place compactor in PVC pipe on dirt then place a 16.78kg brick for 4 seconds on the circle to compact the dirt.
iii. Repeat steps i. - ii. until an 8 layer plug is created with 8 compactions
iv. Repeat steps i. - iii. until 5 plugs are created
v. Repeat steps i. – iv., reducing layers by half and doubling the time the brick sits on the circle compactor
1. For the
first repetition, reduce the layers to 4 and double the compaction
times to 8 seconds
2. For the second repetition, reduce the layers to 2 and double the compaction times to 16 seconds
3. For the third repetition, reduce the layers to 1 and double the compaction times to 32 seconds
2. Ready Experiment2. For the second repetition, reduce the layers to 2 and double the compaction times to 16 seconds
3. For the third repetition, reduce the layers to 1 and double the compaction times to 32 seconds
a. Place plug
tube horizontally into PVC valve so that side with the dirt is away
from the valve.
b. Make sure the valve is shut
c. Support so the long pipe is vertical
3. Conduct Experimentb. Make sure the valve is shut
c. Support so the long pipe is vertical
a. Fill
vertical pipe, 133cm with tap water to the top
b. Start the stopwatch when you turn the valve
c. Stop the stop watch when the plug breaks and record
4. Repeat with other dirt plugs in this compaction
groupb. Start the stopwatch when you turn the valve
c. Stop the stop watch when the plug breaks and record
5. Repeat with other compaction groups
6. Average results within each group
RESULTS
The original purpose of this experiment was to determine the effect of dirt compaction in layers on the ability to hold water.
The results of the experiment were inconsistent because there is no recognizable trend. The results were low then high having no recognizable relationship.
See the table and graph below.
CONCLUSION
My hypothesis was that the more compacted layers there were the longer it would hold back water.
The results indicate that this hypothesis should be rejected, because of the inconsistence results. The problem is that the harder you compact it the plug is compacted so great there is no path of air for it to follow instead of the plug breaking it is pushed out by the pressure. Though if you are compacting the plug little air cracks will be left. If the cracks are found by the water it will lead it out when you start to see the water come out it erodes half of the plug in one second. The problem is that the air cracks maybe harder to find.
After thinking about the results of this experiment, I wonder if the type of material used as a plug would make a difference in the time it held water. I also wonder if the amount of time the soil was being compacted would matter at all. For example if each compaction lasted 64 seconds instead of 32, would that improve the water resistance? What if the dirt was dry, damp, or frozen? One could also test the amount of dirt used in the plug. Would twice as much dirt double the time water was held?
If I were to conduct this project again I would conduct more trials probably ten or 12. I would also test a plug with a larger number of layers, perhaps 16.
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Introduction: Levees and earthen dams are earthen used to hold back water in rivers, lakes, or ponds. They are often used as protection against floods. Hurricanes, flash floods, and floods are destructive storms, which harm human population, crops, and shelters. Water Pressure: Water pressure is the force pushing against an object due to the weight of water. Water pressure can be just the mass of water pushing on an underwater object. A pump or compressor can also cause it too. Open areas such as seas are static (not moving). Enclosed areas like pipes are static or dynamic (moving). Hurricanes: Hurricanes are powerful swirling storms with over 119mph winds that start over oceans. Hurricanes are formed when air flows from a high-pressure area to a low-pressure area causing the winds. Hurricanes form in regions near the equator. From the Equator, hurricanes travel ether north or south. In the northern hemisphere, hurricanes spin counterclockwise. In the southern hemisphere, hurricanes spin clockwise. This is due to the Earth’s rotation. A tropical storm is a small hurricane with 38 to 118 mph winds. The eye is the center or heart of a hurricane that is extremely low pressure around 10 to 20 miles wide. The winds form around the eye’s yet the eye is calm. The speed of the winds depends on the eye diameter. The bigger the eye is, the slower the winds. The smaller the eye is, the faster the winds. Hurricanes are given both male and female names, A-Z except Q, U, X, Y, and Z. Only North American hurricanes start naming at A every year. If a tropical storm turns in to a hurricane it’s called Hurricane Fred not Tropical storm Fred. Flash Floods: Flash floods are when a low area is flooded quickly. This can be caused when a dam collapses or when rivers or streams rise rapidly probably by heavy rain. A flash flood can happen also when the soil is saturated and it’s raining heavily. During flash floods the water travels to a low area rushing down hill harmfully creating a dangerous area. Dirt Compaction: Dirt compaction is when dirt is being packed or pushed together into a tight area. For better resistance dirt is compacted in layers or frozen. Dirt compaction is commonly done on earthen structures such as dams or levees. Levees: Levees are mounds of dirt near waterways or oceans to hold back water. Floods make some levees naturally, though humans place most of them there to protect small or larger populated areas. If a levee breaks it will be worse than if there was no levee there, especially if the water has risen on to the levee; so instead of having a flood there is a flash flood. There are lots of levees in the Eastern U.S. because of all the hurricanes hitting there. Earthen Dams: Earth dams are a wall of earthen material across a moving waterway, used to change where it flows, slow the current, or makes a reservoir (artificial lake) for fresh water supply. Dams usually make a reservoir upstream of the dam. A spillway is usually attached to the dam that controls the water let out of the dam. Dams are made in areas such as cities or farms were there is a great need for water. Erosion: Erosion is the process by which natural water and weather break down rock. When rock is broken down a river changing the shape of the land moves it. This usually takes millions of years such as the Grand Canyon. Ice is a big part of erosion because when water gets in a crack and is frozen it expands breaking the rock. Summary: Earthen dams and levees are helpful structures that give protection and keep water where you need it or turn it away from where you don’t want it, but if they are destroyed it can be more severe. Hurricanes and floods are the destructive storms that hit against dams and levees. They destroy crops, shelter, animals, and humans. |
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Barnes, Gray. “Hurricanes.” World Book Encyclopedia. October 26, 2005. Microsoft Explorer Baueslien, Valerie; Jacoby, Mary. “Other Ways to Deter Floods.” Wall Street Journal, Eastern Edition. September 21, 2005: A15 Granter, John. “Building Better Levee.” September 16, 2005 <http://www.wired.com/news/technology> Lafen, John M. “Erosion” Word Book Encyclopedia 1/11/2006. Safari. Lauber, Patricia. Hurricanes. New York: Scholastic Press, 1996. p. “Levee.” Encarta Encyclopedia. 2004 CD-ROM Mays, Larry. “Levee.” World Book Encyclopedia. 1999 |
ACKNOWLEDGEMENTS
I would like to thank the following people for helping make my project possible:
• My parents for helping with my experiment.
• Mr. Newkirk for editing my papers.
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