SOI: Smart Concrete, A Science Perspective

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SCIENCE OF INNOVATION
Smart Concrete
A Science Perspective (Grades 6–12)
Lesson plans produced by the National Science Teachers Association.
Video produced by NBC Learn in collaboration with the United States Patent and Trademark Office
and the National Science Foundation.
Background and Planning
About the Video
This video discusses the age-old material known as concrete and how modern innovations
could change the way in which the stability of this composite is determined. Dr. Deborah
Chung, an expert in composite materials and structural science at The State University of New
York at Buffalo, has developed a new type of concrete, dubbed smart concrete, which is
composed not only of the basic ingredients of any concrete—water, a cement binder, and
gravel—but also carbon fibers. These fibers easily conduct electricity and can be used to
measure conductivity across a block of the smart concrete. According to Chung, any changes in
its resistivity might indicate the presence of minute cracks or other types of deformation in
concrete structures long before they are visible to the naked eye. While Chung’s innovation is
not yet commercially available, she has patented her invention and continues to do research on
this innovative material that is able to sense, in real time, the forces to which it is subjected.
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Series opening
Concrete and its many uses
Defining innovation
Introducing Chung
Chung’s smart concrete
Potential benefits of smart concrete
Laboratory testing of Chung’s innovation
Patent for composite material strain/stress sensor
Summary
Closing credits
Language Support To aid those with limited English proficiency or others who need help
focusing on the video, make available the transcript for the video. Click the Transcript tab on
the side of the video window, then copy and paste into a document for student reference.
Framework for K–12 Science Education
ESS3.B: Natural Hazards
PS1.A: Structure and Properties of Matter
PS2.A: Forces and Motion
ETS1.A: Defining and Delimiting Engineering Problems
ETS2.A: Interdependence of Science, Engineering, and Technology
ETS2.B: Influence of Engineering, Technology, and Science on Society and the Natural World
Smart Concrete, A Science Perspective (Grades 6–12)
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Emphasize Innovation
The Innovation Process
Inspiration The innovation highlighted in Science of Innovation (SOI): Smart Concrete is the
development of a new type of concrete material with built in electrical sensors to detect stress
before the impacts of stress become visible. Dr. Chung and others think this technology would
be an innovation to this building material so that any deformation and failure in roads, bridges,
buildings, and other structures made from concrete might be detected before they are visible.
Take Action with Students: Discuss with students the impetus for Dr. Chung’s inspiration to add
carbon fibers to concrete. One way to look at it is that she was simply experimenting with
materials to see what would happen. Guide students to understand that she had experience
with (1) the properties of concrete and structural materials, and (2) knew that carbon fibers are
able to conduct electricity. She didn’t know beforehand whether this combination would result
in any significant discovery, but was able to recognize the importance of the discovery once she
analyzed the results from her experiments.
Innovation and STEM
The innovation highlighted in Science of Innovation (SOI): Smart Concrete incorporates many
aspects of STEM (Science, Technology, Engineering, and Mathematics) education. For example,
required science knowledge includes an understanding of the properties of the components of
concrete and the chemical reactions that form it. Also, the understanding of electrical
conductivity is at the heart of what makes concrete a “smart” concrete. Math concepts involve
around the calculations that enable comparisons of deforming actions. Starting with a vision
and relying on science and math knowledge, Chung and her colleagues improved on concrete
building technology by adding carbon fibers to concrete, which gave the composite electrical
properties. By monitoring changes in resistivity, the fibers in the smart concrete become
deformation sensors in real time. The engineering design process involved is limited by
constraints related to materials, time, and costs. Although Chung’s smart concrete is not yet
commercially available, its development will likely include various economic, safety,
manufacturability, and sustainability constraints.
Take Action with Students
 Using the Design Investigations section of Facilitate Inquiry as a guide, encourage students
to investigate compressional force on a composite.
 Brainstorm with students a list of constraints within which engineers would have to work to
develop and test smart concrete. For example, will smart concrete be as inexpensive and
easy to produce as normal concrete is? Will it be as strong and last as long as normal
concrete does? How much carbon fiber is the ideal amount to add to a specific mass of
concrete? Will the changes in resistivity affect other properties of the smart composite? Are
there are special disposal requirements or environmental risks with carbon fiber?
Smart Concrete, A Science Perspective (Grades 6–12)
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Facilitate Inquiry
Encourage inquiry using a strategy modeled on the research-based science writing heuristic. Student
work will vary in complexity and depth depending on grade level, prior knowledge, and creativity. Use
the prompts liberally to encourage thought and discussion. Student Copy Masters begin on page 9.
Explore Understanding
Use photographs or real-life examples with which students are familiar to show the many ways
in which concrete is used today and how it was used in the past. Help students understand why
this simple composite is so useful by using the following prompts.
 Concrete is a material that is….
 Examples of objects made from concrete that I see everyday include….
 Concrete is used to make many objects and structures because this material is….
 Concrete can crack because….
Show the video SOI: Smart Concrete and encourage students to jot down notes while they
watch. Continue the discussion of the usefulness of concrete as well as how carbon fibers are
used to change some of the properties of the material, using prompts such as the following:
 When I watched the video, I thought about….
 Concrete is made of….
 The experts in the video claimed that _____ because….
 Carbon fibers are….
 Adding carbon fibers to concrete changes the concrete by….
 Smart concrete is different from normal concrete because….
 Chung and her colleagues tested the smart concrete by….
 Advantages of using any type of concrete for building include….
 Disadvantages of using any type of concrete for building include….
Ask Beginning Questions
Stimulate small-group discussion with the prompt: This video makes me think about these
questions…. Then, ask groups to list questions they have about composite materials such as
concrete and how they might react to forces. Ask groups to choose one question and phrase it
in such a way as to be researchable and/or testable. The following are some examples:
 How does the composition of a composite affect its strength?
 How does setting time affect the strength of a composite?
 Do forces exerted from different directions affect a composite in the same way?
 How much force will it take to cause a certain mass of a composite material to crack?
 How much force will it take to cause a certain mass of a composite material to crumble?
 What happens if a reinforcing material is added to the composite?
Design Investigations
Choose one of the following options based on your students’ knowledge, creativity, and ability level and
your available materials. Actual materials needed will vary greatly based on these factors as well.
Possible Materials Allow time for students to examine and manipulate the materials that are
available. Doing so often aids students in refining their questions or prompts new ones that
should be recorded for future investigation. In this inquiry, students might investigate a
Smart Concrete, A Science Perspective (Grades 6–12)
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composite that can be compared to actual concrete such as plaster of Paris. Students would
need water, small containers such as wax-coated cups or milk cartons, and additives such as
fine sand, coarse sand, pea gravel, wood chips, and shredded paper. Students should use glass
rods or large wooden craft sticks to mix the composites, and might consider using kilogram
masses, vise grips, C-clamps, a workbench vise, or a simple hydraulic press or car jack to exert
forces on their composite samples. Force sensors, hands lenses, rulers, and measuring tapes
might also be useful for the investigations. Make sure students understand how to use these
tools and measurement devices safely.
Safety Considerations: To augment your own safety procedures, see NSTA’s Safety Portal at
http://www.nsta.org/portals/safety.aspx.
Open Choice Approach (Copy Master page 9)
1. Groups might come together to agree on one question for which they will explore the
answer, or each group might explore something different. Students should brainstorm to
form a plan they would have to follow in order to answer the question, which might include
researching background information. Work with students to develop safe procedures that
control variables and enable them to make accurate measurements. Encourage students
with prompts such as the following:
 Information we need to understand before we can start our investigation is….
 The variable we will test is….
 The variables we will control are….
 The steps we will follow are….
 We will record and organize our data using….
 To conduct our investigation safely, we will….
2. Give students free rein in determining how they will explore the chosen question. However,
make sure they understand that they must ask and get your approval on their procedures
before they start any investigation. To help students envision their investigations, use
prompts such as the following:
 The materials we will use are….
 We will make our composite cylinders/blocks by….
 We will measure the compressional force by….
 We will repeat our test _____ times and determine an average force (e.g., number of
turns of the vise screw) for our composite cylinders.
Focused Approach (Copy Master pages 10–11)
The following exemplifies how students might investigate the question of how much
compressional force, which could be provided by a workbench vise, is needed to cause a
composite cylinder/block to develop a crack.
1. Ask students questions such as the following to spark their thinking:
 What is a force?
 Why type of force is compression—a pushing force or a pulling force?
 How can you exert compressional force on a composite cylinder?
 How can this compressional force be measured?
Smart Concrete, A Science Perspective (Grades 6–12)
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
2.
3.
4.
5.
Will the rate at which the force is applied have any effect on when and how many cracks
form?
 Will cylinders/blocks made from the same batch of plaster of Paris have the same
strength?
 Will combining more or less of an additive (sand, gravel, etc.) to a plaster of Paris and
water mixture affect the composite’s strength?
 Does the particle size of the additive (sand, gravel, etc.) impact the composite’s
strength?
Give students free rein in determining how they will explore their chosen question.
However, make sure they understand that they must ask and get your approval on their
procedures before they start any investigation. Students might create cylinders from
different batches of plaster of Paris that use the same amount of powder but different
volumes of water. Or, they might mix the plaster and water according to the package
directions and add the same amounts of additives such as fine sand, coarse sand, pea
gravel, wood chips, or shredded paper. Then, students might use a workbench vise or a car
jack to exert force on their composite cylinders or blocks. Ensure that students brainstorm a
list of variables that are involved in their proposed experiments and determine which can
be controlled and which cannot. To help students envision their investigations, use prompts
such as the following:
 The variable we will test is….
 The responding variable will be….
 The variables we will control, or keep the same, are….
 We will make our composite cylinders/blocks by….
 We will measure the compressional force by….
 We will repeat our test _____ times and determine an average force (e.g., number of
turns of the vise screw) for our composite clylinder(s)/block(s).
 To conduct our investigation safely, we will….
When the cylinders have completely hardened, students might anchor one cylinder
between the vise plates so that the plates are just touching the ends of the cylinder.
Students might then turn the vise screw one complete turn to exert pressure on the
cylinder, then observe the composite for any deformation (cracks, crumbling, etc.) and
continue this process until a crack or crumbling is observed. As students carry out their
experiments, make sure they realize that, just as in the video, deformation may be taking
place within the composites even though no cracks or crumbling are visible to the eye. Use
prompts such as:
 As we turn the vise screw, the plates of the vise are….
 We know that deformation is taking place because….
Make sure students understand the importance of making accurate measurements as well
as repeating trials to ensure that their data are reliable by using these, or similar prompts:
 We will measure the amount of force exerted by the vise by….
 We will repeat the procedure at least _____ times because….
 To find an average value for the amount of force used to deform our composites, we
will….
Students might continue their investigations by exploring how different additives affect the
amount of force needed to crack their composites, or by testing how the direction from
which a force is applied affects the stability of their composites. Some students might want
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to investigate the compressional strength of different brands of plaster of Paris, or use a
different tool to exert force on their composites.
Media Research Option
Groups might have questions that are best explored using print media and online resources.
Students should brainstorm to form a list of key words and phrases they could use in Internet
search engines that might result in resources that will help them answer the question. Review
how to safely browse the Web, how to evaluate information on the Internet for accuracy, and
how to correctly cite the information found. Suggest students make note of any interesting
tangents they find in their research effort for future inquiry. Encourage students with prompts
such as the following:
 Words and phrases associated with our question are….
 The reliability of our sources was established by….
 The science and math concepts that underpin a possible solution are….
 Our research might feed into an engineering design solution such as….
 To conduct the investigation safely, we will….
Make a Claim Backed by Evidence
As students carry out their investigations, ensure they record their observations. As needed,
suggest ways they might organize their data using tables or graphs. Students should analyze
their data and then make one or more claims based on the evidence their data shows.
Encourage students with this prompt: As evidenced by… I claim… because….
An example claim relating the amount of force needed to cause a composite to crack might be:
As evidenced by repeated trials using different samples of the same composite, I claim that an
average of 4 turns of the vise’s screw was needed to crack the composite because each cylinder
developed one or more cracks when the screw was turned between 3-6 times.
Compare Findings
Encourage students to compare their ideas with others—such as classmates who investigated
the same or a similar question, material they found on the Internet, or an expert they chose to
interview. Remind students to credit their original sources in their comparisons. Elicit
comparisons from students with prompts such as the following:
 My ideas are similar to (or different from) those of the experts in the video in that….
 My ideas are similar to (or different from) those of my classmates in that….
 My ideas are similar to (or different from) those that I found on the Internet in that….
Students might make comparisons like the following:
My ideas are similar to my classmates’ in that the data from groups that researched the same
question had similar results—cylinders made by following the mixing instructions on the
package had similar compressional strength values.
Reflect on Learning
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Students should reflect on their understanding, thinking about how their ideas have changed or
what they know now that they didn’t before. Encourage reflection, using prompts such as the
following:
 I claim my ideas have changed from the beginning of this lesson because of this evidence…
 My ideas changed in the following ways…
 I wish I had been able to spend more time on….
 Another investigation I would like to try is….
Inquiry Assessment
See the rubric included in the student Copy Masters on page 12.
Incorporate Video into Your Lesson Plan
Integrate Video in Instruction
Explain Freeze the video at 0:44 to show the three basic ingredients of any concrete—water, a
cement binder, and gravel. Explain that concrete is a composite, or type of mixture in which
two or more substances with significantly different properties are combined in any proportions.
Remind students, if needed, that the individual components in a composite are not chemically
combined and thus retain their properties.
Homework Ask students to closely observe some concrete objects and structures such as
sidewalks, walls, and driveways near their houses or apartments, and note differences in the
colors and textures of the concrete used. Have students relate the differences to the loads the
structures or objects need to bear or to the aesthetics of the object or structure.
Using the 5E Approach?
If you use a 5E approach to lesson plans, consider incorporating video in these Es:
Explore Use the Design Investigations section of Facilitate Inquiry to support your lessons on
force and properties of matter.
Elaborate Use the video to encourage students to learn more about concrete, including how it
reacts when subjected to different types of forces, how its stability is tested, and some of the
advantages and disadvantages of this building material.
Connect to … Engineering
Improve the Design Have students find out why steel reinforcing rods, or rebars, are often
imbedded into concrete structures. Students might repeat their investigation and add
toothpicks, pipe cleaners, or coffee stirrers to their mixtures to model their effect on strength.
Prompt Innovation with Video
After students watch the video, have them research patents associated with smart concrete.
They can do so with an Internet search on Google.com/patents using search terms such as the
following. If time is limited, point students toward the patent examples.


Electrically conductive fibers
Stress
Smart Concrete, A Science Perspective (Grades 6–12)
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
Carbon nanofibers
Resistance/resistivity
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




Strain
Tensile
Tension
Composite/building material
Carbon fibers





Conductivity/conductance
Elongation
Cement/concrete
Sensor/gauge
Load
Patent Examples
US 5,379,644 – method for detecting strain or stress of a structure
US 5,422,174 – electromagnetic wave shielding building material
US 5,581,039 – ceramic/concrete body subjected to stress and undergoes gradual change
US 6,079,277 – strain or stress sensor
US 6,276,614 – strain sensor formed in a sheet shape from composites
US 7,921,727 – sensing system for monitoring the structural health of a structure
Suggest students read abstracts of patents that attract their attention. Then hold a discussion
about how various innovators are improving on the process. Use prompts such as the following:
 This patent is for _____, which is related to the invention shown in the video by….
 This patent describes _____, which differs from the invention shown in the video in that….
 I think doing/making _____ would be an innovation because….
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COPY MASTER: Open Choice Inquiry Guide for Students
Science of Innovation: Smart Concrete
Use this guide to investigate a question about composites. Write your report in your science
notebook.
Ask Beginning Questions
The video makes me think about these questions….
Design Investigations
Choose one question. Brainstorm with your teammates to come up with ways in which you
might be able to answer the question. Look up information as needed. Add safety precautions.
Use the prompts below to help focus your thinking.
 The variable we will test is….
 The variables we will control are….
 The steps we will follow are….
 We will record and organize our data using….
 To conduct the investigation safely, we will….
Record Data and Observations
Record your observations. Organize your data in tables or graphs as appropriate.
Make a Claim Backed by Evidence
Analyze your data and then make one or more claims based on the evidence your data show.
Make sure that the claim goes beyond summarizing the relationship between the variables.
My Evidence
My Claim
My Reason
Compare Findings
Review the video and then discuss your results with classmates who investigated the same or a
similar question. Or do research on the Internet, or talk to an expert. How do your findings
compare? Be sure to give credit to others when you use their findings in your comparisons.
 My ideas are similar to (or different from) those of the experts in the video in that….
 My ideas are similar to (or different from) those of my classmates in that….
 My ideas are similar to (or different from) those that I found on the Internet in that….
Reflect on Learning
Think about your results. How do they fit with what you already knew? How do they change
what you thought you knew about the topic?
 My ideas have changed from the beginning of this lesson because of this evidence….
 My ideas changed in the following ways….
 One concept I still do not understand involves….
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COPY MASTER: Focused Inquiry Guide for Students
Science of Innovation: Smart Concrete
Use this guide to investigate a question about how a composite such as concrete reacts to
compressional forces. Write your report in your science notebook.
Ask Beginning Questions
How much compressional force will it take to cause a composite material to form a crack?
Design Investigations
Brainstorm with your teammates to come up with ways in which you might be able to answer
the question. Decide on one idea and write a procedure that will allow you to safely explore the
question. Use the prompts below to help focus your thinking.
 The variable we will test is….
 The responding variable will be….
 The variables we will control, or keep the same, are….
 The materials we will use are….
 The steps we will follow include….
 We will repeat our test _____times to make sure….
 To conduct our investigation safely, we need to….
Record Data and Observations
Organize your observations and data in tables or graphs as appropriate. The table below is an
example of testing different cylinders or blocks made of the same composite.
Plaster of Paris Cylinders/Blocks and Compression
Composite Cylinder/Block
Force (number of turns of the vise screw) Applied to Produce a Crack
1
2
3
4
5
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Make a Claim Backed by Evidence
Analyze your data and then make one or more claims based on the evidence shown by your
data. Make sure that the claim goes beyond summarizing the relationship between the
variables.
My Evidence
My Claim
My Reason
Compare Findings
Review the video and then discuss your results with classmates who investigated the same or a
similar question. Or do research on the Internet or talk with an expert. How do your findings
compare? Be sure to give credit to others when you use their findings in your comparisons.
 My ideas are similar to (or different from) those of the experts in the video in that….
 My ideas are similar to (or different from) those of my classmates in that….
 My ideas are similar to (or different from) those that I found on the Internet in that….
Reflect on Learning
Think about what you found out. How does it fit with what you already knew? How does it
change what you thought you knew?
 I claim that my ideas have changed from the beginning of this lesson because of this
evidence….
 My ideas changed in the following ways….
 One concept I still do not understand involves….
 One part of the investigation I am most proud of is….
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COPY MASTER: Assessment Rubric for Inquiry Investigations
Criteria
Initial question
Investigation
design
Variables
Safety procedures
Observations and
data
Claim
Findings
comparison
Reflection
1 point
Question had a yes/no
answer, was off topic, or
otherwise was not
researchable or testable.
2 points
Question was
researchable or testable
but too broad or not
answerable by the
chosen investigation.
The design of the
While the design
investigation did not
supported the initial
support a response to
question, the procedure
the initial question.
used to collect data
(e.g., number of trials,
or control of variables)
was not sufficient.
Either the dependent or
While the dependent
independent variable
and independent
was not identified.
variables were
identified, no controls
were present.
Basic laboratory safety
Some, but not all, of the
procedures were
safety equipment was
followed, but practices
used and only some
specific to the activity
safe practices needed
were not identified.
for this investigation
were followed.
Observations were not
Observations were
made or recorded, and
made, but were not
data are unreasonable in very detailed, or data
nature, not recorded, or
appear invalid or were
do not reflect what
not recorded
actually took place during appropriately.
the investigation.
No claim was made or
Claim was marginally
the claim had no
related to evidence
relationship to the
from investigation.
evidence used to support
it.
Comparison of findings
Comparison of findings
was limited to a
was not supported by
description of the initial
the data collected.
question.
Student reflection was
limited to a description
of the procedure used.
Student reflections
were not related to the
initial question.
Smart Concrete, A Science Perspective (Grades 6–12)
3 points
Question clearly stated,
researchable or testable,
and showed direct
relationship to
investigation.
Variables were clearly
identified and controlled
as needed with steps and
trials that resulted in data
that could be used to
answer the question.
Variables identified and
controlled in a way that
resulting data that can be
analyzed and compared.
Appropriate safety
equipment used and safe
practices adhered to.
Detailed observations
were made and properly
recorded and data are
plausible and recorded
appropriately.
Claim was backed by
investigative or research
evidence.
Comparison of findings
included both
methodology and data
collected by at least one
other entity.
Student reflections
described at least one
impact on thinking.
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