Research Paper

Waste Reduction Concrete Production

Concrete is widely used product world-wide for construction, sidewalks, buildings, and etc. The purpose of my project is to see if the strength of concrete can be affected by the ratio of sand to cement, and what happens to the components of concrete during the curing process, and how long does concrete take to cure for maximum strength. My project will show people how different amounts of sand to cement affect concrete in strength, texture and hardness.

Concrete is a construction material composed mainly of cement, sand, and water. Concrete is used in a lot of constructions, sidewalk, roads, foundations of buildings and structures, and many other things are built using concrete. It is very important to construction, and it can be strengthened in tension by adding reinforcing bars made of iron or steel. Concrete has relatively high compressive strength, but significantly lower tensile strength, and as such is usually reinforced with materials that are strong in tension (Concrete). About 7.5 cubic kilometers of concrete are made each year that is more than one cubic meter for each person on Earth (Concrete). During the Roman Empire, Roman concrete was made from quicklime, pozzolanic ash, and an aggregate of pumice. The widespread use of concrete in many Roman structures has ensured that many survive to the present day (Concrete). The secret of concrete was lost for 13 centuries until 1756, when the British engineer John Smeaton pioneered the use of hydraulic lime in concrete, using pebbles and powdered brick as aggregate (Concrete). Portland cement was first used in concrete in the early 1840s (Concrete). This version of history has been challenged however, as the Canal du Midi was constructed using concrete in 1670 (Concrete). The elasticity of concrete is relatively constant at low stress levels but starts decreasing at higher stress levels as matrix cracking develops. Concrete solidifies and hardens after mixing with water and placement due to a chemical process known as hydration. Hydration and hardening of concrete during the first three days is critical. The water reacts with the cement, which bonds the other components together, eventually creating a stone-like material. Concrete is used more than any other man-made material in the world. Curing is one of the most important steps in concrete construction, because proper curing greatly increases concrete strength and durability, this happens after the concrete has been placed, and cement requires a moist, controlled environment to gain strength and harden fully. Fine and coarse aggregates make up the bulk of a concrete mixture. Sand, natural gravel and crushed stone are mainly used for this purpose. Concrete hardens as a result of hydration: the chemical reaction between cement and water. If concrete can be made better and stronger, than it will help resist destruction of buildings and structures during earthquakes and floods.

In conclusion, I have learned of the key steps to make concrete, and what concrete is made of, What kinds of things are concrete used for, and its importance in society, such as how much is it used for, and for what, like construction, sidewalks, building, and etc.

Works Cited

· "Concrete: Table of Contents." Department of Materials Science and Engineering, University of Illinois Urbana-Champaign. University of Illinois Urbana-Champaign, 1995. 3 December 2009.

· "Cement and Concrete Basics: Frequently Asked Questions." Portland Cement Association. Portland Cement Association, 2006. Web. 3 December 2009.

· "Curing Concrete: What is curing and what does it do to the concrete." Concrete network. Fortress stabilization system and many more, 1999. Web. 3 December 2009.

· “Curing Concrete.” Tkproduct.com. TK Products, N.P. Web. 3 December 2009.

· "Concrete." Wikipedia, the Free Encyclopedia. Wikipedia, 2 December 2009. Web. 3 December 2009.

Related Terms

AGGREGATE - Crushed stone, slag or water-worn gravel that comes in a wide range of sizes that is used to surface built-up roofs.

ANGLE IRON – A piece of iron that forms a right angle and is used to span openings and support masonry at the openings. In brick veneer, they are used to secure the veneer to the foundation. Also known as shelf angle.

CORROSION - The deterioration of metal by chemical or electrochemical reaction resulting from exposure to weathering, moisture, chemicals or other agents or media.

COURSE - A single layer of brick or stone or other building material.

CURING – In concrete application, the process in which mortar and concrete harden. The length of time is dependent upon the type of cement, mix proportion, required strength, size and shape of the concrete section, weather and future exposure conditions. The period may be 3 weeks or longer for lean concrete mixtures used in structures such as dams or it may be only a few days for richer mixes. Favorable curing temperatures range from 50 to 70 degrees F. Design strength is achieved in 28 days.

CURING AGENT – One part of a multi-part sealant which, when added to the base, will cause the base to change its physical state by chemical reaction between the two parts.

GRAVEL - Loose fragments of rock used for surfacing built-up roofs, in sizes varying from 1/8" to 1 3/4".

MORTAR
A mixture of sand, lime and water used to cement stones and bricks together. When it dries it becomes very hard. The early Mormons used the same mud, in more liquid form, for mortar that they used to make adobe.

MORTAR TYPES - Type M is suitable for general use and is recommended specifically for masonry below grade and in contact with earth, such as foundations, retaining walls and walks. Type M is the strongest type. Type S is suitable for general use and is recommended where high resistance to lateral forces is required. Type N is suitable for general use in exposed masonry above grade and is recommended specifically for exterior walls subject to severe exposures. Type 0 is recommended for load-bearing walls of solid units where the compressive stresses do not exceed 100 lbs. per square inch and the masonry wall not be subjected to freezing and thawing in the presence of excessive moisture.

PORTLAND CEMENT - A mixture of certain minerals which when mixed with water form a gray colored paste and cure into a very hard mass.

SEPARATION – In concrete application, what happens to concrete when it is dropped directly with a flat chute causing the concrete to separate, usually occurring at a 1:2 slope.

Abstract

One goal of this project is to find out how the ratio of sand to cement changes the strength of concrete, and if waste products can be used in concrete. Another goal is find out how Fly Ashes affect the strength of concrete.

Put on a dust mask and gloves before experimentation. Mix batches with different ratios of sand and Portland cement and then add water according to your senses. Then put the mixture into identical molds. Then let the mixtures rest in a location with room temperature and humidity. Allow the bricks to set for at least 2-3 days. Then take the bricks out, and test them. You can test them by putting the bricks on two small pieces of wood, which are set on top of a weight scale, and then apply force by hand on the brick with a long piece of wood, and record when the brick breaks.

The best ratio came out 50% sand 50% cement. In Testing with Fly Ash, 33% Fly Ash came out with the better result, but the strength wasn't improved much.

50% sand 50% cement was the best ratio. Though the strength was not improved, but was about the same as the original, so we could use waste products like Fly Ash in concrete, and it would make concrete cheaper and you would be recycling waste.

Reference - Presentation

• "Concrete: Table of Contents." Department of Materials Science and Engineering, University of Illinois Urbana-Champaign. University of Illinois Urbana-Champaign, 1995. 3 December 2009.

• "Cement and Concrete Basics: Frequently Asked Questions." Portland Cement Association. Portland Cement Association, 2006. Web. 3 December 2009.

• "Curing Concrete: What is curing and what does it do to the concrete." Concrete network. Fortress stabilization system and many more, 1999. Web. 3 December 2009.

• “Curing Concrete.” Tkproduct.com. TK Products, N.P. Web. 3 December 2009.

Future developments - Presentation

I can add on to the entire experiment, with different ingredients like limestone, and also test the affect of weather on concrete. Also I can test other percentages of Sheetrock and Fly Ash.

Application - Presentation

• Construction and Concrete production companies, builder and engineers can use my project to improve concrete.
• Reduce waste.
• Reduce the cost of concrete.

Conclusion - Presentation

Based on the results Fly Ash retained the same strength thought Sheetrock didn’t, so my hypothesis was half right.
Though the strength was not improved, but was close to the original, so we could use waste products like Fly Ash in concrete, and it would be cheaper and you would be recycling waste.

Data and Results - Presentation Cont.

Data and Results - Presentation Cont.

Data and Results - Presentation

Procedure - Presentation

Put on a dust mask and rubber or vinyl gloves before mixing and handling the wet concrete.
Mix batches of concrete using sand and Portland cement into different ratios in a bowl.
Add water and mix thoroughly, then pour into molds to make 3 - 4 bricks.
Then, place the concrete solution in the molds (trays) and label them accordingly to their mixture.
Allow the bricks to set for at least 2 days.
Then dissemble bricks from their molds, and test them.
To test the bricks, you will have to get a weight scale and get a single table, and put it upside down next to the weight scale.
Put a long piece of wood through the table, and another piece of wood over it loosely.
Then place two small pieces of wood on the weight scale and put the brick over it.
Apply force by hand, and pay attention to how much weight it held, and record the data.

Variables and Constants - Presentation

The constants are the amount of time for the curing process, the same location (temperature, humidity), the Thickness (height), length, and width.
The independent variables are the amount of sand, cement, water, Fly Ash and Sheetrock in the bricks.
The dependent variable is the strength of the concrete mixture.
A plain concrete brick (made without Fly Ash or Sheetrock) is going to be my control for testing the affect of Fly Ashes.

Materials - Presentation

materials for making concrete mixes:
dust mask and gloves
Portland cement
sand
water
bucket for mixing concrete
trowel
a pre-made mold (Tray)
Fly Ash
Sheetrock


materials for testing cured bricks:
1 long piece of wood
2 medium pieces of wood
2 very short pieces of wood
1 sturdy tables or workbenches
Weight scale/bathroom scale.

Hypothesis - Presentation

I think that using Fly Ashes and Sheetrock, would have about the same strength and durability of concrete, or maybe even better.

Questions/Purpose

Can By-products/Waste products be used in concrete, to improve it, or keep it the same?
How do Fly Ashes and Sheetrock affect the strength of concrete?
How does the ratio of sand to cement affect the strength of concrete?

Introduction - Presentation

Concrete is very important to society used in a lot of constructions sites and builds and etc.
Concrete is mainly of cement, sand, and water, and can also include other coarse aggregates and products.
Curing is one of the most important steps.
Fly Ashes is a by-product from the residue of burned coal.
If concrete can be made better and stronger, than it will help resist destruction of building, structures and etc. during earthquakes and floods.
The basis of this project is to find out the best ratio of sand to cement.
The main goal of this project is to see if waste products can be used in concrete.
Another goal is find out how Fly Ashes and Sheetrock affect the strength of concrete.

The Experiences and Aspirations

My experience at the city-wide science fair was great. I think that because of participating in this science fair I feel that I could do better in future science fair competitions like ISWEEP. I also have time to do more trials and test other materials for concrete as well as test it under weather conditions. I also got the idea to test how fibers would work, such as using carbon fibers which could serve as reinforcement for the brick when it's under stress. The special judge also told me that he liked my project and that I am on the right track and should go with my future plans. He also influenced my idea of testing fibers like carbon fiber.

I have applied for ISWEEP and I am hoping to get accepted. I believe I could perform better and I could win something even better or at least as good; Since I would have improved my project, and also know how to present more effectively now.


I'll be updated the post very soon with the Research Plan/Paper, The Presentation I used for city-wide, and pictures. More is on the way...

City-Wide Results

I won 4th place in the Engineering: Materials and Bioengineering category in Senior Division in the Austin Energy Regional Science Festival.

The whole category only got judged by a group of two judges, and I think that might have given me a lower chance to win; also that if we had more group of judges than I could have explained better with more confidence.
I do think that besides the judging, if I could have been able to do all the trials and test all the materials and things I wanted accomplish before city-wide; I could have definately won first or second place.

Before City-wide

I completed project for city-wide.
I have tested Sheetrock in my experiment, and as well Fly Ash.
Though I haven't got to test them together in one mixture, and also I didn't have enough Fly Ash at the moment to test the replacement of cement with Fly Ash.
I do have a lot of plans of things to do and other materials to test in the near future for my experiment; Probably for ISWEEP. I do have some ideas to test materials like limestone, and etc. as well as testing weather conditions and more percentages of FLY ASH.