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Supercomputing Challenge

Storming the Industry: The Effect of Fun Additives

Team: 106


Area of Science: Engineering

Interim: Nature is the major force that damages concrete


School Name: Las Vegas Homeschool Team (Middle School)

Area of Science: Engineering

Title: Storming the Industry: The Effect of Fun Additives to Prevent Concrete Damage due to Freezing and Thawing


Question: What is stronger than concrete and steel?

Answer: Ice J



Winter is a time when concrete is damaged. Water from melted snow and ice is absorbed into the concrete.  When the temperature drops below freezing, the water turns into ice and expands with force. That force is powerful enough to exceed the “yield point” of the concrete and crack it. This problem is very well known in the industry.



When it is freezing outside, one of the steps Mr. Hank Hern, the owner of HHH Construction, does is carefully cover his freshly poured cement with plastic sheets. He does this so that it won’t harden too soon or develop weak areas inside. Once it’s set, however, Mr. Hank’s work is as vulnerable to the freeze-thaw cycle as any other building, driveway or sidewalk. Billingsly Engineering in Las Vegas is spending a lot of time and money trying to figure out how to make New Mexico’s bridges and highways safer. This is because moisture that soaks into concrete, and then expands as ice with the same force, can weaken a bridge and may cause it to crack under pressure, which would be very dangerous. The engineers try to prevent “spalling-“ the breaking off of concrete that exposes rebar, and “delamination-“ longitudinal cracks along the underside of a bridge; by testing concrete samples for durability. They do this by following different recipes for making concrete and then comparing how durable they are. These tests are very intense and interesting to watch, and that’s where I got my idea from. I wanted to study whether I could improve concrete strength by adding new materials that would help form a stronger bond. I picked things that we throw away as trash and that we have a lot of in New Mexico; plastic bags, dryer lint, and pinion shells.



How does the water reach concrete surfaces in the first place? Well, the answer is, this happens naturally. In the winter, water can freeze in many different forms just depending on the temperature, the amount of humidity is in the atmosphere, and how hard the wind is blowing. Here are few of the examples I found in my book.

Frost occurs when water vapor in the air comes in contact with concrete driveways or sidewalks that are already frozen. Frost looks like a coating of fuzzy-appearing crystals (p.572).

Glaze happens when supercooled water lands on a surface that is at freezing temperature or below freezing. When this happens, a smooth clear coating is formed. Even though it’s thin, glaze can freeze and thaw in layers and become dangerously slick (p.572).

Hail is a type of precipitation that falls like rain but in the form of balls or lumps of ice. Balls are formed before falling to earth. This happens when moisture moves up and down in the clouds and that causes the balls to grow in size. According to my book, hailstones can be as small as peas to the size as grapefruits (p.572).

Sleet is tiny pellets of frozen water that looks like granular snow. It falls like rain to create a coating that makes surfaces like sidewalks and bridges dangerous for walking and driving on (p.572).


There are many different ways in which moisture naturally reaches concrete, these are just a few. However it happens, freezing water can negatively affect concrete durability. This is because concrete is permeable. When it’s drenched with water and then cooled below 00C, concrete cracks internally. Ongoing freezing and thawing causes the cracks to grow and may eventually lead to “macroscopic degradation,” the scientific name for “ice damage” (Schulson, Erland M).


Problem Definition: Macroscopic Degradation

Why are some concrete things more affected by macroscopic degradation than others? The basketball court across the street from my house, for example, has a snake-like crack about 15 feet long. We can still play but have to be careful. The concrete parking lot at my sister’s school, however, has a round pothole about eight inches deep. Parents picking up their kids or dropping them off have to drive all the way around it; or smash up their car. Potholes and cracks are examples of “differential weathering” and it has to do with the difference in resistance of various rock types (p. 587). In construction, workers add water, sand and gravel (usually different sizes & shapes of rock) to the cement. These ingredients bind together to form concrete. When chalk and clay has been heated and crushed, Portland cement is made. When water is added, it crystallizes into a mass that binds sand and gravel together (p.102). Sometimes special additives are added. As the concrete hardens, sand and gravel are joined together by the cement and form a rocklike mass with amazing “compressive strengths” (p.102). Compressive strength refers how much weight or pressure it can support. The workers at Billingsly Engineering test compressive strength using a hydraulic ram. The hydraulic ram puts pressure on a concrete samples until they break. Compressive strength is measured in megapascals (MPa) or pounds per square inch (psi). This test takes place after the concrete has had a chance to harden. Normally, that’s twenty-eight days. Twenty eight days is a long wait, especially if there’s an urgent need. Sometimes three-day and seven-day strengths are used to predict 28-day compressive strengths.


Road Construction

Roadway pavement is either flexible or rigid (p.71). Flexible pavement is made up of sand and gravel mixed with a tarry material called asphalt. The base of Flexible pavement consists of a thin layer of asphalt that fills in the cracks. Like a lasagna, roads consist of several layers of harder asphalt, and topped with gravel or stone chips. Another method uses a layer of gravel about 1 to 3 inches thick placed directly on the base. Heavy rollers then smash down the stone layer and then heated tar is sprayed on to hold everything in place.

Rigid pavements are the other type of roadways in New Mexico. Rigid pavement is made of concrete that is 6 to 12 inches thick that is on top of a layer of compacted gravel. Another problem is that concrete shrinks when it is cold outside and expands when hot. This too can cause cracks.


Use of Additives

The workers at Billingsly Engineering test special ingredients in their lab hoping to decrease cold weather damage out in the field. When water freezes and turns into ice, its volume expands by about nine percent. If there is not enough room for this expansion, the ice will break the needles of the interlocking cement paste crystals. Additives are poured in the cement mixer that create small air bubbles inside the concrete when it dries. These air bubbles provide a place for expanding ice crystals to relieve it’s pressure.


Research Objective

There are many things that we normally just throw away that might offer improved workability and resistance to spalling, delamination, and macroscopic degradation. The primary purpose of this study is to determine whether adding additional items improves the durability of hardened concrete.



Permission will be requested to remove enough cement from the mixer to fill 6 forms. The following ingredients will be added:

Form 1: Cement + shredded Walmart bags

Form 2: Cement + dryer lint

Form 3: Cement + pinion shells


The other three forms will be identical to the ones above but will be sprayed with melted Walmart bags before being put in freezer.

Form 4: Cement + shredded Walmart bags, sprayed with

melted Walmart bags

Form 5: Cement + dryer lint, sprayed with melted

Walmart bags

Form 6: Cement + pinion shells, sprayed with melted

Walmart bags


Once hardened, these six blocks will be put into the freezer with the other samples from the original batch. To imitate the freeze-thaw cycle that occurs in the field, they will be frozen then thawed 300 times. (Actually, that’s probably more intense than what happens outside). Finally, all the blocks, including my six experimental ones, will be tested for durability.


Data Analysis

How can computers help us understand? We will be using a program called “Mathematica” to add, subtract, divide and compare the data that we receive. The numbers will tell us which of the blocks are most durable.


Progress to Date

Our methodology has been approved by the owner of Billingsly Engineering. We’re not sure how were going to melt the plastic bags but will figure that out by Thursday, February 22. That’s the day we’ll set our forms. We’re currently practicing with Mathematic on “fake data” to try to learn the program.


Team Members: Moriah Scott (age 11) & Elena Martinez (age 12)


Sponsoring Teacher: Rey Martinez


Consultants: Mrs. Leanne Billingsly, Engineer; Dr. Tahani Hossein, Computer and Mathematical Sciences Department, New Mexico Highlands University.





Team Members:

  Moriah Scott
  Elena Martinez

Sponsoring Teacher: Rey Martinez

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