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. 0:00 0:15 1:07 1:22 1:40 2:51 3:08 4:30 4:47 5:12 0:14 1:06 1:21 1:39 2:50 3:07 4:29 4:46 5:11 5:24 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) 1 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) 2 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) 3 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) 4 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 Smart Concrete, A Science Perspective (Grades 6–12) 5 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 Smart Concrete, A Science Perspective (Grades 6–12) 6 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) Carbon nanofibers Resistance/resistivity 7 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…. Smart Concrete, A Science Perspective (Grades 6–12) 8 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…. Smart Concrete, A Science Perspective (Grades 6–12) 9 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 Smart Concrete, A Science Perspective (Grades 6–12) 10 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…. Smart Concrete, A Science Perspective (Grades 6–12) 11 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. 12