Which Size Sand Particle Used To Make Bricks Makes The Most Durable Brick?
&
Which Brick Is The Most Durable Clay, Cement,
Or Cement Paver?


Carmel L.
1998-99 

 PURPOSE
 HYPOTHESIS
 EXPERIMENT DESIGN 
 MATERIALS 
 PROCEDURES 
 RESULTS 
 CONCLUSION 


 RESEARCH REPORT 
 BIBLIOGRAPHY 
 (optional) APPENDIX 
 (optional) PROJECT LOG

Purpose

Section 1







The purpose of this experiment was to determine which size of the sand particles used to make bricks would be the strongest.  I became interested in this idea when I wanted to learn more about engineering and architecture.  I also thought this project would be a great experience.  The information gained from this experiment can help architects and engineer or local people learn and use the information, and to judge what type of brick to use.

Section 2

The purpose of this experiment was to see which type of brick is the strongest.  I became interested in this idea when I wanted to test commercial bricks for a different project and compare the results with my other experiment as a similar experiment.  Also I wanted to see if the commercial bricks would be stronger.  The information gathered from this experiment can be helpful for people who have or will use bricks for decorative or for building a structure.
 
 

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Hypothesis

Section 1







My hypothesis is that the larger size of silica (#8) will be stronger than the smaller size (#30) for making the bricks.  I base my hypothesis on the research I have done and also a quote from Greg Wilson, a mason, saying, ď The larger particles of sand will make the strongest brick.Ē  Also, the larger sand particles will hold together better than the small size because it takes up more room to hold together for making the bricks.
 
 

Section 2







My hypothesis is that the concrete paver will be the strongest because it has the highest amount of cement in it.  Second strongest will be the clay brick and then the weakest brick will be the concrete brick.  I base my hypothesis from an exact quote saying the same thing in my hypothesis given by Jeff Hayes, a local who sells and knows about bricks.
 
 

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Experiment Design

Section 1

The constants in this study were:
The same amount of sand added to both types of bricks
The portland cement used was the same, and the amount used was similar for both bricks.
 Both bricks were stored in the garage
When the bricks were made, the same wheelbarrow was used
  One shovel was used for both the bricks made
  The scale used was used for both bricks
  One meter tape was used
  The bucket was used for both the bricks
  Weights were used for both brick experiments

The manipulated variable was the different sand particle size added into my bricks.  Their were two experiment groups, one had #30 silica sand added and the other had a #8 silica sand.  The control group was the cement brick used for the Section 2 experiment.

The responding variable was the strength of the bricks and how it compared to the other bricks.  To measure the responding variable I used a meter tape, scale, weights, a compression test, and a ladder to measure the durability of the bricks.

    Section 2

The constants in this study were:
    -the same size of each brick
    -the same place bought
    -the same temperature stored in
    -the same place the bricks were bought
    -the same ladder used for one experiment
    -the same place the compression test was done

The manipulated variable was which type of bricks would be the strongest the cement, cement paver or the clay brick.

The responding variable was the strength of the bricks and how it compared to the other bricks.  To measure the responding variable I used a meter tape, weights, scale, a compression test, and a ladder to measure the durability of the bricks.
 
 

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Materials
Quantity
Item Description
4,536 kg
#8 Silica
4,536 kg
#30 Silica
4,536 kg
Portland Cement
 9,072 cc 
Water
1
Wheelbarrow
1
Shovel
1
Mold
1 small can
Oil
4,536 kg
Weights
30
Clay Bricks
30
Cement Bricks
30
Cement Paver
1
Bucket
1
Compressive Strength Tester

 

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Procedures

Section 1







1. Gather or buy all materials needed for the experiment.
2. Make the bricks (see appendix on the procedures for making the bricks.)
3. With the bricks made start on the 3 different experiment.

Making the bricks
1. Gather all materials needed like the sand, portland cement, and water.
2. Measure the amount of sand to add into the mixture.
3. Next, measure the amount of portland cement needed in the mixture.
4. Combined the mixture together in a wheelbarrow and mix well.
5. Then add the water needed until it becomes a watery substance (not too watery or the cement wonít hold together.)
6. Mix together with the sand and cement.
7. Then coat the molds with oil so the cement mixture wonít stick on it and will come out easily.
8. Put the mixture into the molds and make sure it is filled up and smoothed down.
9. The next day, take out the bricks from the molds or if brick has not hardened yet, wait until the day after.
10. Then, wait at least 3 days until testing the project.  Have the bricks cured.

Curing
1. After the bricks are taken out of the molds, store it where it will not be disturbed.
2. Sprinkle with water and then wait 3 days until testing.

You may also soak the brick in water and then take it out but it will take longer to dry.
The curing process makes the bricks stronger.

(Test 1) Durability Test

1. First, set up a ladder to stand on.
2. From 8 feet drop the bricks down.
3. Check how many pieces it broke down to. *
4. Test 5 of each of the 2 experimental bricks.
5. Then record the results.

(Test 2) Weight Test

1. Find a plank or make a plank to support the brick on top and so weights can be hanged from the bottom.
2. Put the brick on top of the plank and tie a rope down the middle.
3. Then, hang a bucket tied to the rope.
4. Then add weights into the bucket (I added rocks for weights)
5. Test 5 of each of the 2 experimental bricks.
6. After, record the results of the experiments.

(Test 3) Compression Test

1. Gather 5 of each of the 2 experimental bricks.
2. Then test the bricks at a soil lab with a compressor.
3. Put the brick into the compressor and add flour to the top and the bottom to make the surface smooth.
5
4. Then test the brick with the compressor.
5. Then after the brick starts cracking stop the compressor and read the meter on how much pressure was put on the brick.
6. Then write the results for later use.

* The broken pieces counted were only the ones at, at least 1-inch pieces.
 
 

Section 2







1. Buy the materials needed like the bricks (cement, cement paver, and the clay bricks.)
2. Next, find the length, width, and height of each project.
3. After, that then start with the three experiments that was done to the home made bricks
4. Follow each step of the tests (Durability, Weight, and Compressive) in Section 1.
 
 

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Results

Section 1







The original purpose of this experiment was to determine which size of the sand particles used to make bricks would be the strongest.  The results of my experiment was that the average strength of the #8 silica was stronger than the #30 silica.  The #8 silica in all the tests except for one was stronger.  In the Compression Test the average on the # 8 silica was 6,610 kilograms.  But the #30 silica was only 4,280.6 kilograms, for itís average.  On the Durability Test #8ís average of times dropped before breaking was 1.4 and the #30 silica was only 1.2.  For the Weight Hang Test, none of the bricks broke, at the highest weight, which was

Section 2

The original purpose of this experiment was to see which type of brick is the strongest.  The results of the experiment were that the average strength of the cement paver was stronger, and the clay brick came next and lastly was the cement.  The cement paver in all of the tests except for one, was the strongest of the three.  In the Compression Test the average on the cement paver was 18,432.792 kg.  But the cementís average was only 11,315.808 kg, and the clay was 12,061.224 kg.  On the Durability Test the cement paverís average was of times dropped before breaking was 6.2 and the cement was 1.6, and the clay was 1.8.  For the Weight Hang Test, none of the bricks broke just like the Section 1 even though those were home made.  I also noticed that on the Durability Test, when the results I did were done, the average number of pieces broken from the #30 brick was higher.  I concluded that the stronger the brick was the less pieces broke off.  Also, the weaker the brick is the more pieces broke off.
 
 

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Conclusion

Section 1

My hypothesis is that the larger size of silica (#8) will be stronger than the smaller size (#30) for making the bricks.  I base my hypothesis on the research I have done and also a quote from Greg Wilson, a mason, saying, ď The larger particles of sand will make the strongest brick.Ē  Also, the larger sand particles will hold together better than the small size because it takes up more room to hold together for making the bricks.
The results indicated that this hypothesis should be accepted, because the cement paver was the strongest and the clay brick next, and the cement last. If I were to conduct this project again I would test three different types of the same kind of brick and find out which is the strongest between them.  Also, I would test the bricks and see which one would hold the most water or moisture.
 
 

Section 2




My hypothesis was that the cement paver would be the strongest, and then the clay, lastly the cement brick.  The results indicated that this hypothesis should be accepted, because the cement paver was the strongest and the clay brick next, and the cement last.

Because of the results of this experiment, I wonder if more cement added does effect the strength and amount of time cured would have another effect too.  If I were to conduct this project again I would test three different types of the same kind of brick and find out which is the strongest between them.  Also, I would test the bricks and see which one would hold the most water or moisture.
 
 

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Research Report

Brick
Bricks are used in construction or for decorative purposes.  Some bricks are soaked in water and then dried by sun, but most are dried in kilns.  They are stronger than stone and cost very little, some bricks can be made from glass.  They resist dampness and heat.
 In ancient Mesopotamia and Palestine, bricks were the chief building material because they had little wood or stone.  About 9,000 years ago Jericho inhabitants in Palestine were building bricks. Many other ancient people used bricks like the Babylonians and the Sumerian.  Then later the Persians and the Chinese started using bricks for structural uses.  For example the Great Wall of China is made of bricks.  Romans also used them to make large structures such as baths, amphitheaters, and aqueducts, which they covered with marble facing.
 During the Middle ages, in the Byzantine Empire and in Northern Italy, in the Low Countries, and in Germany they prized bricks because stone was scarce.  The tradition continued through the Renaissance and in English Georgian architecture, colonists brought bricks to North America.  Native Americans had already known about bricks and have used them. Maya and Olmec made their pyramids out of bricks and faced them with stone.  Still, today bricks are used in different, and a variety of ways.

Sedimentary Rock
 Sedimentary rock is one of the 3 major kinds of rocks on earth.  It is 70% to 75% of the total area of the earth.  Itís made form loose sedimentary that becomes more and more.  It can also be made from chemicals that precipitate out of water.  This kind of rock can provide information of past environments.  Most sedimentary rocks are characterized by parallel or discordant bedding that reflects variations in either the rate of deposition of the material or the nature of the matter that is deposited.

Classic Rocks
 Classic sedimentary rocks are also known as terrigenous rocks because of the particles that make up this kind of rocks, comes off the land and the particles that come off are the classic rocks.  These kinds of rock range in size form very small to as large as boulders, meters long.  They get carried off by wind to far areas, boulder sized rocks arenít carried off as far.  These particles may go through many types of erosions before it undergoes lithification.
 There are four main kinds of classic rocks, shale, sandstone, conglomerates, and sedimentary breccias.  These different kinds of classic rock are distinguished by their size and are also common sedimentary rocks of mechanical origin.

Other Rocks
Mechanical rocks, or fragment rocks, are composed mineral particles produced by the mechanical disintegration of other rocks and transported without chemical deterioration, by flowing water.  They are carried into larger bodies of water, where they are deposited into layers.
 Materials making up chemical sedimentary rocks may consist of the remains of microscopic marine organism precipitated on the ocean floor, as in the case of limestone.

Sand
 Sand is loose and small in size (like micro size).  It consists of silica, with some mica, feldspar, magnetite and other resistant minerals.  Chemicals and mechanical ways are ways that sand is formed.  Which happens during erosions.  When they are firstly formed the sand is sharp and angular.  While they go through more erosion by way of wind or water the sand becomes rounded and smaller.
 Sand is and important materials for most soils is found a lot on riverbanks, on shores of lakes ant the sea, and arid regions.  Different types of sands are used in casting molds and in ceramics, plasters, and cements.

Masonry
 Masonry is the art of using stone, practiced since ancient time.  Ancient Egyptians, stonework was generally squared and fitted, no adhesive or mortar was used to join the stones together.  Ancient examples of this masonry made up of huge and different sizes of rocks and stone laid together without mortar have been found in Europe, in China, Peru, Greece, and Romans developed masonry techniques that have continued in practice with few changes to the present day.
 Rubble and ashlar are the two broad categories in masonry.  Rubble is composed of irregular and coarsely jointed quarried or fieldstone.  Ashlar is made up of carefully worked stones set with fine close joints.  Either of the two can be laid in mortar.  When it is laid without mortar it is called dry masonry.

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Cement
 Cement is any material that hardens and becomes strongly adhesive after applied in plastic form.  The term cement is often used as a similar meaning to glue and adhesive.  In engineering and building construction cement usually refers to very fine powdered, manufactured substance consisting of gypsum plaster or portland cement that hardens and adheres after being mixed with water.
Cement is used for different reasons one is, to hold sand and gravel
together with portland cement and that forms concrete.  It is also used to put different surfaces together made of various materials.  Another use can be for coating surfaces to protect them from being damaged by some outside force of nature or by chemical reasons.  Cement can be made in different ways and for different uses.  The cement used in construction is sometimes named for their commonly reported place of origin such as the Roman cement, or it can be named after some time of material that resembles that cement for example, the portland cement which produces a concrete resembling the Portland stone used for building in England.  Cement that resists high temperatures are called refractory cements.
 When cement hardens because it is reacting to the oxygen or carbon dioxide in the atmosphere or the water, alcohol, or oil that makes it evaporate.

Portland Cement
 Typical portland cements are mixtures of tricalcium silicate, tricalcium silicate, tricalcium aluminate, and dicalcium silicate in varying proportions, together with small amounts of magnesium and iron compounds.  Gypsum is often added to slow the hardening process.
 These active compounds in cement are unstable, and when water is added they rearrange their structure.  The hardening of the cement is mostly caused by the hydration of tricalcium silicate, which from the watery substance becomes hardened.  These substances bind together the particles of sand or stone, which are always included in a mortar or concrete mixture into a hard mass.

Silica and Quartz
 Quartz is composed of silicon, or silica.  It is also the most common of all materials.  It is distributed around the world as a constituent of rocks and in form of pure deposits.  It is an essential constituent of igneous rocks such as granite, rhyolite, and pegmatite, which all contain an excess of silica.  Quartz forms veins and nodules in sedimentary rock, principally limestone.  Sandstone, a sedimentary rock, is composed mainly of quartz.  Precious metals, such as gold, are found in sufficient quantity in quartz veins to warrant the mining of quartz to recover the precious mineral.  Quartz is also the primary constituent of sand.

Properties
 The size of the crystals varies form specimens weighing a metric ton to minute particles that sparkle in rock surfaces.  Quartz is also common in big sizes, which contain particles ranging in size from coarse grained to micro size that cannot be seen by the naked eye.

Varieties
The coarsely crystalline varieties of quartz are, in general, transparent, and lustrous.  Rock crystal, a colorless form of quartz, usually occurs in distinct crystals.

Concrete
 Concrete is an artificial engineering material made from a mixture of portland cement, water, fine and coarse aggregates and a small amount of air.  It is the most widely used construction material in the world.
 Concrete is the only major building material that can be delivered to the job site in a plastic state.  This unique quality makes concrete desirable as a building material because it can be molded to any form or shape.  Concrete can be used for many different jobs and comes in many surface textures and colors.
 Other qualities of concrete is that its strength, economy and durability.  Depending on the mixture of materials used, concrete will support, in compression, 703,070 or more g/sq. cm.  The tensile strength of concrete is much lower, but by using properly designed steel reinforcing, structural members can be made that are as strong in tension as they are in compression.  The durability of concrete is evidenced by the fact that concrete columns built by the Egyptians more than 3,600 years ago are still standing.

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Mixing Concrete
Before concrete is mixed, workers measure the proper amount of the materials.  The strength and durability of concrete highly depends on how much water is added to the concrete.  If too much water is added the paste will be weak and wonít hold together.  If water added is reasonable the concrete will hold together better.  So the less water added the stronger the cement will be.
 Concrete can be mixed by hand or by machine.  Using a machine is better in a way that it coats all aggregates and fills all the spaces between the aggregates with cement paste.  And also a machine makes more uniform batches of cement.

 Placement
 While the concrete is still wet the cement is place in molds, made of wood, plywood, or steel.  The mold holds the concrete until it will harden.  Concrete must be pressed down and made into the corners to prevent open spaces.

Curing
 Curing makes the concrete harden properly.  After the concrete is firm enough to resist marring it should be sprinkled with water, then covered with wet canvas, wet burlap, or wet sand.  The cover keeps the concrete form drying too quickly.  A chemical reaction between portland cement and water makes the concrete harden.  For this reason, the longer concrete remains moist, the stronger it becomes.
 Concrete shrinks when it hardens.  This happens because it loses moisture as it dries.  The chemical reaction between portland cement and the water produces heat.  When large amount of concrete are used the heat must slow down, making dams, cold water running in pipes in the cement makes the heat slow down.  But cement companies have made a different kind of portland cement which produces less heat.

How Cement is made
 Portland cement contains about 60% lime, 25% silica, and 5% alumina iron oxide and gypsum making up the rest of the materials.  These can be also found in sand, just different proportions.  The gypsum regulates the hardening time of the cement.

Erosion
 From the earthís surface white rocks and soil are broken loose naturally.  Erosion Makes changes to land areas, making mountains were down, filling in valleys, and making rivers appear or disappear.  It takes thousands and even millions of years for erosion to do those kinds of thing.  Farming and mining are examples of how erosion can be made faster.
 Weathering is the first process of erosion.  This process breaks rocks and other materials into smaller pieces.  One example of weathering is when water freezes.  When water freezes it expands and the rocks can break because of this.  Other causes can be wind, water, chemicals, living organisms, and heat from the sun.
 After this weathering process the particles are moved.  Like by wind, wind moves objects through great distances.  Water currents can also move objects from a riverbed into the sea.
 Erosion can be harmful or helpful.  Benefiting people, the formation of soil through breaking up of rock.  Into mouths of rivers and on valley floors rich soil is deposited.  Erosions have made great geological formations.  For example the Grand Canyon was made through millions of years by erosions.
 A harmful effect of erosion is that it takes way farmland of productive topsoil.  Because of this it is one of the leading threats to food supply.  Fertilizer might also be carried into rivers and into lakes making it harmful.  Eroded soil can also block irrigation ditches.
 People can influence the occurrence of erosion.  By making chemicals that are not harmful to the environment.

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Bibliography

Brick, Encarta, 97

Cement, Encarta 97

Concrete, Encarta 97

Crawford, Maria Luisa, Sedimentary Rock, The World Book Encyclopedia, 1988.

Dott, Robert H. Jr., Sedimentary Rock, Academic American Encyclopedia, 1995.

Hayes, Jeff, local brick seller, Western Materials, Dec. 28,1998.

Laften, John M., Erosion, World Book Encyclopedia, 1999.

Masonry, Encarta, 97

Neal, John A., Cement, World Book Encyclopedia, 1991.

Quartz, Encarta, 97

Sand, Encarta, 97

Siebel, Don, Engineer, Soils Lab, Jan. 28,1999.

Wilson, Greg, mason, Masonry, Dec. 16,1998.
 
 























































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