Design & Marketing of Concrete Products Curriculum

Transcription

1 Design & Marketing of Concrete Products Curriculum [Also taught as PIE Partners in Engineering Program] How can we design a concrete product for sale that has environmentally friendly attributes? Curriculum Overview... 2 Sample Teaching Schedule Outline... 3 Concept map Concrete curriculum:... 4 Assessment Opportunities... 5 Summary of NYS MST Standards Covered:... 6 Problem Statement... 9 Lesson Plans Lesson 1 Introduction to program, solid waste, unit problem Lesson 2 Product Brainstorm concrete Lesson 3 Concrete Research Lesson 4 Waste aggregates and material properties Lesson 5 Making concrete & safety Lessons 6 and 7 Foam Bridge Experiment- Forces and Stresses Lab Lesson 6&7- Spaghetti Lab- Alternative to Foam Bridge Lesson Lesson 6 Forces and Stresses the shorter (lecture based) lesson for tension and compression Lesson 8 Testing Cylinders for Compressive Strength Lesson 9 Evaluating results Lesson 10 Weighted Objectives Table and Optimum Mix Sheet Lesson 11 Value of Product Lesson 12 Prototype production Lesson 13 Wrap-up / Final assessment

2 Curriculum Overview Concrete is one of our most valuable building materials, yet innovations in how concrete can be made, including making and using it in more environmentally friendly ways continues to be developed. Changing the aggregate materials for example is one important change. Concrete products can be made utilizing waste materials as aggregate to provide a valuable use for these materials, reduce their disposal in a landfill, and reduce the need to extract sand and gravel resources from the earth. Concrete products that are porous can also be made to increase water infiltration and reduce runoff. This property is especially important for applications such as parking lots that otherwise create a substantial impervious surface. In one version of the curriculum, eighth-grade technology students address the opportunity for integrating solid waste as aggregate materials in concrete. The curriculum begins with an introduction to solid waste and concrete materials. Students brainstorm about potential waste aggregates that they can integrate into concrete and then make test cylinders out of a wide range of materials. These concrete specimens are tested at Clarkson University facilities provide data on the strength of the concrete mixes that can be used for design choices. Students then make concrete products (e.g., stepping stones) and develop a marketing plan to sell the products based on their environmentally friendly attributes. In the Fall 2008 semester the curriculum is being adapted to consider porous concrete products in alignment of the research of Clarkson s Dr. Narayanan Neithalath, Assistant Professor of Civil and Environmental Engineering. 2

3 Sample Teaching Schedule Outline Lesson Plan Lesson 1: What is solid waste? Lesson 2: What can we do with solid waste? Introduce concrete Lesson 3: Concrete research- WWW/ Packet Lesson 3: Wrap Up Concrete Research Lesson 4: Material Properties and Waste Aggregates Lesson 5: How to make concrete, safety Mix & pour test cylinders Lesson 6/7: Forces and Stresses Lesson 8: Breaking concrete test cylinders (Field trip to Clarkson) Lesson 9: Go over graphs of cylinder results Lesson 10: Weighted objectives table / Determine Optimum Mix Lesson 11: Value of concrete product- marketing Lesson 11: Wrap Up Marketing Lesson 12: Prototype Production Lesson 13: Wrap-up / final assessment Concrete exam / project rubric/ surveys of fellows 3

4 Concept map Concrete curriculum: PIE Solid waste - What it is Non-biodegradable materials persist Biodegradable materials Landfills 3 R s Compost Products that can be made from SW Concrete for non-biodegradable Concrete - What it is Making concrete Waste aggregates Concrete as an industrial material Safety / handling Types of materials Sources / uses Material Properties Processing / forming Concrete test cylinders Tension/compression Weighted decision analysis Pouring molded products Value of the Concrete Product 4

5 Assessment Opportunities In-class worksheets and Homework assignments: Vocabulary worksheet Solid Waste what can we use? (in class brainstorm worksheet) Homework: what we throw away? Concrete WEB research answers to worksheet questions and presentation to class Homework: Forces and Stress Value of our Product 2 worksheets available Lab Activities: Material Properties or Physical Properties lab/worksheets Lesson 6 - (2) lab alternatives: Foam Bridge or Spaghetti lab (forces and stress) data sheet/graphs Cylinder Compression test data analysis/graphs Weighted Objectives Table Projects: Marketing product Final concrete product Unit Exam 5

6 Summary of NYS MST Standards Covered: Standard 1: Analysis, Inquiry and Design Engineering Design: 1: Engineering design is and iterative process involving modeling, optimization finding the best solution within given constraints which is used to develop technological solutions to problems within given constraints identify needs and opportunities for technical solutions from an investigation of situations of general or social interest locate and utilize a range of printed, electronic and human information resources to obtain ideas consider constraints and generate several ideas for alternative solutions, using group and individual ideation techniques; defer judgment until a number of ideas are presented; evaluate ideas and explain why the given solution is optimal. in a group setting, test solutions against design specifications, present and evaluate results, describe how the solution might have been modified, discuss tradeoffs that might have been made. Standard 2 Information Systems 1. Information technology is used to retrieve, process and communicate information and as a tool to enhance learning students use a range of equipment and software to integrate several forms of information in order to create good quality audio, video, graphic and text-based presentations students use spreadsheets and data base software to collect, process, display and analyze information systematically obtain accurate and relevant information pertaining to a particular topic from a range of sources Standard 3: Mathematics Measurement: 5: Students use measurement in both metric and English units to provide a major link between abstraction of mathematics and the real world in order to describe and compare objects and data Standard 4 Science Students estimate, make and use measurements in real-world situations apply formulas in direct measurement activities explore and produce graphic representation of data using calculators/computers Physical Setting: 3: Matter is made up of particles whose properties determine the observable characteristics of matter and its reactivity observe and describe properties of materials such as density and conductivity 6

7 Standard 5 Technology Engineering design: 1: Engineering design is an iterative process involving modeling and optimization to develop technological solutions to problems with given constraints. students identify needs and opportunities for technical solutions from an investigation of situations of general or social interest locate and utilize a range of printed, electronic and human information sources to obtain ideas consider constraints and generate several ideas for alternative solutions test their solutions against design specifications Tools, resources and technological processes: 2. Technological tools, materials and other resources should be selected on the basis of safety, cost, availability choose and use resources for a particular purpose based on analysis and understanding of their properties, cost, availability and environmental impact use hand tools and machines to change materials into new forms Computer technology: 3. Computers as tools for design, modeling, information processing, communication and system control have greatly increased human productivity and knowledge. Use a computer to connect to and access needed information from various internet sites. Impacts of technology: 6. Technology has had positive and negative impacts on individuals, society and the environment and humans have the capability and responsibility to constrain or promote technological development students describe how outputs of a technological system can be desired, undesired, expected or unexpected Standard 6: Interconnectedness: Common themes Systems thinking describe how the output from one part of a system can become input to other parts Optimization: 6. In order to arrive at the best solution that meets the criteria within constraints, it is often necessary to make tradeoffs. determine the criteria and constraints and make tradeoffs to determine the best decision use graphs of information for a decision making problem to determine the optimal solution Standard 7 Interdisciplinary Problem Solving Connections: 1. The knowledge and skills of mathematics, science and technology are used together to make informed decisions and solve problems, especially those related to issues of science/technology/society, consumer decision making, design, and inquiry into phenomena. students analyze science/technology/society problems and issues at the local level and plan and carry out a remedial course of action 7

8 students design solutions to a real-world problem of general social interest related to home, school or community using scientific experimentation to inform the solution and applying mathematical concepts and reasoning to develop a solution Strategies: 2. Solving interdisciplinary problems involves a variety of skills and strategies, including effective work habits; gathering and processing information; generating and analyzing ideas; realizing ideas; making connections and presenting results. Students participate in an extended, culminating MST project. The project would require students to: work effectively; gather and process information; generate and analyze ideas; observe common themes; realize ideas and present results. 8

9 Problem Statement Scenario: A current problem related to advances in technology and our contemporary lifestyle is how to deal with the enormous amount of solid waste generated by our society. Over the years we have experienced many changes in our lifestyle, mostly making things easier but resulting in the creation of more and more waste. For example, milk which was at one time sold in refillable glass bottles is now purchased in disposable paper cartons or plastic jugs. This system is easier, we don t have to clean the bottles and return them to the dairy, but it adds paper and plastic containers to our solid waste. The average person in the U.S. disposes of roughly 4.5 pounds of solid waste per day. Most of this waste ends up in landfills, where it is buried in a controlled environment to prevent contamination of the surrounding area. As a result, there are literally mountains of trash now existing on the planet. Our available landfill space is running out. Environmental engineering is a relatively new technological field, an outgrowth of man s need to solve problems that have been created by poor decision making and mismanagement related to the impact of technological advances on the environment. They are called upon to find solutions to restore the equilibrium or balance between nature and society. One branch of environmental engineering deals specifically with finding ways to ensure that the disposal of our waste is done in a safe, responsible manner. Problem: Nonbiodegradable wastes Solutions to the solid waste problem are not limited to the waste disposal end. As products are created and developed, engineers need to bear in mind the waste that these products will eventually generate, and the resulting implications to the environment. One way to reduce the amounts of waste that are disposed is to avoid creating the waste in the first place. Many materials that we normally throw away may actually be used in the creation of another product. Developing usable products from waste materials is not a new concept, but is becoming more and more important as the amounts and types of solid waste increase. Your problem assignment is to find a way to reuse solid waste in the generation of a new product. Your specific tasks include: 1. Investigate materials in the solid waste that may be adaptable as durable, raw materials for another product. 2. Explore the creation of different types of products using waste materials. 3. Determine the waste material most suitable for use in your product. 4. Design and create a prototype of your product. 9

10 5. Test the prototype for acceptability, make improvements as necessary. 6. Manufacture your product and use it in a way that benefits your school or community. 10

11 Lesson Plans Lesson 1 Introduction to program, solid waste, unit problem 1. Background Narrative: Through the eras of humankind s development, humans have created ways to make their existence easier. Native cultures had a profound respect and appreciation for the living environment. For example, they hunted only what they needed to survive and used all parts of their prey to meet their food, clothing and shelter needs. Modern man, having had the advantage of great technological advances throughout the 20 th century, has not demonstrated the same level of appreciation for the environment at all times. While advances in technology have improved modern man s existence certain decisions relative to his environment became a lesser priority than the goods and products manufactured to sustain his lifestyle. The result or impact has been the creation of stress on the fragile equilibrium of the natural environment. Environmental engineering is a relatively new technological field, an outgrowth of man s need to solve problems that have been created by poor decision making and mismanagement related to the impact of technological advances on the environment. Environmental engineers are called upon to find solutions to restore the equilibrium or balance between nature and society. But environmental engineers cannot solve all of the environmental problems caused by advancing technology - all engineers should consider environmental impacts associated with the products, processes and services they design and offer. One current problem related to advances in technology and our contemporary lifestyle is how to deal with the enormous amount of solid waste generated by our society. Some solid waste statistics (4.5 lbs trash/person/day is generated in USA a bag of trash that contains 4.5 lb. would be a good illustrative example) breakdown for the municipal fraction of solid waste (2001): paper and paperboard 38% yard and food waste 23% Plastics 11% Metals 8% Glass 6% Other 14% Note that much of this high rate of trash generation is associated with the choices we make in our lives and our modern society, usually with the goal of added convenience or comfort. For example we now use disposal milk jugs rather than reusable, refillable glass bottles that have to be cleaned before they are collected or returned for reuse. 11

12 2. Performance objectives Standards: Students will be able to explain what solid waste is. Students will demonstrate an understanding that advances in society and technology have contributed to the solid waste problem. Students will be able to list problems with current solid waste disposal methods. Students will be able to define the terms reduce, reuse and recycle. NYS: 4.7, 5.5, 5.6, 7.2 US Sci: 5.3, 5.4, 5.6 US Tech: 2.1, 2.2, , Resources Background on solid waste: see EPA solid waste web site: Vocabulary worksheet Silverstein, S., Where the Sidewalk Ends, Harper Collins Publishers, New York, ISBN Bill Nye Science Guy Garbage 1 OR Beth Pike video entitled Garbage into Gold 2 Technology Problem Solving Method Overhead Problem statement (make overhead or display in classroom) Worksheet: Solid Waste what can we use? Homework assignment: What we throw away 4. Instructions This is the first day make it fun and exciting!! 1. (Less than 5 mins) Take a few minutes to introduce yourselves, if you are new in the classroom! Who are you? What do you study at college? Why do you study engineering? Does anyone know what an engineer does?... Engineers solve problems! Engineers use science and math to make improvements to the human environment and way of life. Inform the students that over the next few weeks you ll be working with them to solve an engineering problem. 2. (3-5 mins) This is our problem! point to the bags of trash. Can anyone guess what our problem is? The US produces more than 245 million tons of solid 1 Order at 2 Order at 12

13 waste per year. That is equivalent to 4.5 lbs of trash per person per day. Have one student come up and lift a 4.5 lb bag of trash. Show pie chart with percentage breakdown of solid wastes. ***Also in here as another option: Read the Shell Silverstein s Where the Sidewalk Ends Sarah Cynthia Sylvia Stout Would Not Take The Garbage Out. or, show short clips from Bill Nye video Garbage or Garbage into Gold 3. (10 mins) Activity: have students come up and quickly organize trash into groups shown on pie chart. Percentages should match what is on pie chart to give visual representation of solid waste breakdown. 4. Pass out fill in the blank vocabulary worksheet. Have students work on the worksheet during the Bill Nye video. 5. (20 mins) Start Bill Nye video. 6. (10 mins) Go over vocabulary worksheet. Ask for examples- give me an example of a biodegradable material, etc. 7. (5 mins) Introduce the problem that we will be solving over the next 3 weeks: We want to reduce the amount of non-biodegradable solid waste that the community disposes by turning it into something valuable that the community can use. (ask: why would we want to do that? So it will not accumulate and cause problems as in poem!) 8. (15 mins) Short lesson on problem solving: How will we solve this problem does anyone have a good approach to solving a problem? Ask how many of them consider themselves to be good problem solvers. o Introduce the technology problem solving method (show poster). o Ask students if they have seen this before! Identify the steps on board with them, to reinforce. Emphasize that this is an iterative process. o Give an example of using the problem solving method, applying it to a very simple problem: what will I wear today? Field responses to each step and write on board. Define problem (what to wear) Describe the results you want (to be dressed appropriately, look good, be warm enough, etc.) Gather information (What s the weather? What s clean? What still fits? What do I feel like?) Think of solutions (pull out a few outfits) Choose best solution (best choice from the available options) Implement solution (get dressed!) Evaluate results, make changes (look in mirror, go outside, etc ) 13

14 9. (5 mins) Define where we are on the problem solving method Describing the problem, describing the results we want. Next step gather information, think of solutions. Then we will choose a solution, implement it, and evaluate whether or not it works. (This is engineering!) 10. (2 min) Closure reiterate the problem statement. If you watched the movie, ask what valuable products were shown in the video (oil from tires, soil from compost). Ask students if they think we can make oil from tires in tech class. If you didn t watch the video, ask students what types of products they think might be made from some of the materials they found in the trash (e.g., fleece from recycled plastic). Indicate that in tomorrow s class we will brainstorm and decide what valuable product we can make from solid waste so that less is going to the landfill. 11. Collect student vocabulary sheets or have them saved in a binder for later use. Tell students that they will be graded on all the material you cover, so they need to save their work! 12. Distribute homework assignment and go over it. Students will be asked to record, for the next 3 days, the solid waste that they generate, and consider whether items are biodegradable or non-biodegradable and if they can be reused or recycled. 14

15 The Technological Method of Problem Solving Solving a problem is faster, easier and has better results if you follow a procedure. But we must also remember that problem solving may require you to go back and forth between these steps, they are not always followed in order. The procedure below shows the seven steps of the problem solving spiral. We will use these as we solve our problem. Implement the solution 6 Describe the problem 1 Evaluate results and make necessary changes 7 Describe the results you want 2 Reenter the design spiral at any step to revise as necessary 3 Gather information 5 Chose the best solution 4 Think of solutions Adapted from Hacker, M, Barden B., Living with Technology, 2 nd edition. Delmar Publishers, Albany NY,

16 Solid Waste Vocabulary Sheet Name: Solid Waste - Biodegradable Non-biodegradable Landfill Reduce Reuse Recycle 16

17 Solid Waste Vocabulary Sheet Name: _key Solid Waste - any discarded material that would not normally go down the drain. Biodegradable materials that were once living tissues (biotic). These wastes can be broken down by other living organisms into simple substances. Non-biodegradable Composed of materials that were never living tissues (abiotic). For example, mineral ores. Living organisms cannot break down these wastes into simple substances. Landfill _A system of trash and garbage disposal in which the waste is buried according to a formal disposal plan, within a special site designed by humans to contain the wastes. Reduce _to diminish in size, amount, extent, or number the amount of materials that are discarded. Reuse to use materials again for the same intended purpose, especiallyl after reclaiming or reprocessing. Recycle To process waste materials through a series of changes or treatments in order to regain material for human use. 17

18 Name: Date: Homework Assignment: What we throw away. For the next three days, record the solid waste that you generate and complete the table solid waste item Check one biodegradable non-biodegradable Can it be Recycled or Reused? 18

19 Solid Waste What Can We Use? What are some types of things that you might find in solid waste? Which can we use to solve our problem? Which cannot be used to solve our problem? Vocabulary: Biodegradable: Non Biodegradable: Which types of solid waste materials can we use to solve our problem? 19

20 Lesson 2 Product Brainstorm concrete 1. Background Narrative A growing awareness and recognition of the negative impacts of such solid waste disposal practices as incineration and landfill has led to the investigation of alternative, environmentally friendly, methods. Such focused exploration by scientists and engineers has led to the implementation of what are now referred to as the 3 R s of solid waste management: Reduce Reuse Recycle Reduce refers to the practice of minimizing materials that could potentially become solid waste. Wherever possible, less is better. For example, can two Styrofoam boards provide the same protection in shipping a product as four? The second component to the 3R s is Reuse, the implementation of an item with the intent of utilizing its original form and function. For example, returnable bottles are not only a less expensive method of purchasing some beverages but a more environmentally friendly way as well. Recycling calls for the destruction of elements in their original form for the purpose of reutilizing them in the manufacturing of other products. Glass bottles when pulverized and treated can be re-shaped for use in other glass products. Widespread acceptance and practice of the three R s can help to reduce problems associated with solid waste disposal, simply by reducing the amounts of waste that ultimately must be disposed of. However, future projections of effectiveness, in the face of a growing human population and greater technological advances, is in question. Humankind s ability to be resourceful and innovative in the solution of this challenge will be severely tested. The role of engineers from all disciplines, as well as the role of the individual consumer, will be critical in this process. Every person who generates waste must start critically thinking about his or her waste production, implementing ways to reduce the amount of waste they produce or finding ways to reuse or recycle that waste. Concrete represents a valuable building material that may offer a repository for utilizing certain categories of solid waste materials. Through an understanding of what concrete is and how it is made, students will be able to select suitable waste materials as aggregates. We now need to repeat our problem solving process with a new problem Make a concrete product utilizing waste materials. As a part of the overall problem solving method, we need to use engineering design principles to choose our materials and product, and to plan the process for constructing or making our prototype. The collection of experimental data to support our decisions will be required, as will a logical approach to pick suitable aggregates based on multiple technical, social and aesthetic criteria. The approach used by the students throughout this process reflects the approach used by practicing engineers. Students need to perform research to gather answers to questions they have about their problem solution. Ways to do research include: do an experiment, look up information in

21 the literature (library or WWW), or ask an expert. Through an understanding of what concrete is and how it is made, students will be able to select suitable waste materials as aggregates. The World Wide Web helps to provide the understanding that we need to implement this solution. Students will share the information they have gathered on their group s concrete topic with the entire class. By the end of the lesson students should have a good grasp on the information covered in each concrete research topic. This will give students a very good basic understanding about how concrete is made and tested, how it is affected by weathering, and some of its physical properties. Some key facts about concrete that are pertinent to this lesson include: Concrete is a mixture that becomes hard following a chemical reaction. There are 5 types of Portland cement (Types I-V). The properties of finished concrete will depend on which type of cement is used. The ratio of water to cement in most concrete mixtures is about 0.5:1 by weight. For example, if you used 2 pounds of cement in your concrete you would need to add 1 pound of water to your mixture. In most concrete mixtures sand is used as a fine aggregate and pea stone is used as a course aggregate. During the curing process concrete gains most of its strength. Concrete hardens due to hydration. Hydration only occurs if there is enough water to react with the cement. For this reason concrete needs to be kept wet during curing, by frequent watering and covering with wet cloth or plastic to hold in moisture. Concrete is usually tested after 7 or 28 days of curing. Testing at 7 days will provide a good basis to compare different mixtures (provided that all mixtures have cured for the 7 days), but by the 28 th day the concrete has gained most of its strength. Concrete s strength is most commonly tested by applying compressive force to a sample until it fails. The compressive strength is measured in PSI. Air entrainer is a material added in very small amounts to the concrete mix, to help trap air into the finished product. When concrete which is air entrained has cured, it has millions of tiny air bubbles. These air bubbles give water a place to expand when it freezes. Without these bubbles the concrete would crack much more easily after many freeze/thaw periods. Concrete types that end in an A, are air entrained. For example Types IA, IIA, and IIIA are air entrained but Types I, II, and III are not. 2. Performance objectives Students will be able to recognize different materials that are currently made from solid waste. Students will be able to recognize concrete production as a useful way to reuse solid waste materials. Students will be able to explain where the new problem (How do we make concrete?) fits into the entire curriculum and the larger problem.

22 Standards: Students will be able to list different research methods. Students will be able to discriminate, from a large amount of gathered data, which pieces of information are relevant or important to solving our problem. Students will be able to answer questions about several concrete topics, using the knowledge gained from group discussion. NYS 2.1, 2.2, 5.3, 5.5 US Sci: 2.3 US Tech: 1.3, 3.2, 4.1, Resources Examples of recycled, reused materials (e.g., polartec fleece, plastic lumber, glass bottles, plastic containers, cardboard or paperboard, concrete) Research Worksheets (in Lesson 3) Access to the internet, or if unavailable, information packets for the students containing printed resources Teacher s copy of internet resources / web sites PowerPoint files (for teacher): 4. Instruction plan 1. (5 min) Introduction 1. Concrete Basics 2. Aggregate Properties a. Remind students of our problem statement We want to reduce the amount of non-biodegradable solid waste that the community disposes by turning it into something valuable that the community can use. Show problem solving spiral transparency -Today we are going to brainstorm to generate ideas, choose a potential solution and then learn more about that particular solution reenter the spiral then to make additional choices. b. Discuss what would make a product useful. c. What non-biodegradable wastes do you think we could use? (write suggestions on board recall list of materials found in trash) i. possibilities include rubber, tires, plastic, glass, metal 2. (10 min) Discuss the idea of making usable products from solid waste materials. The 3 Rs reduce, reuse, recycle suggest that many useful products can be made from non-biodegradable waste materials. a. Provide various materials for demonstration and discussion, which are examples of solid waste being Reduced, Reused and Recycled (good examples for reduced category, bring in some packaging types that show how waste is

23 reduced when you use less packaging, for example, or even using the back sides of paper reduces the amount of paper used. For reused and recycled glass bottles, fleece jacket, concrete stepping stone, plastic lumber, recycled paper, both purchased and handmade.) Hold samples up or pass around the class, have students guess what they think the original waste materials were that went into making the product. b. What is the difference between reuse and recycle? Reuse to use materials again for the same intended purpose, especially after reclaiming or reprocessing. Recycle To process waste materials through a series of changes or treatments in order to regain material for human use. (have students write on their vocabulary sheets) c. We are mainly interested in ways to reuse (that s specified by our problem statement). Engage students in identifying additional examples of items that are reused or recycled. (new things are coming along all the time!) Point out to the students that although most human waste goes into the landfill, some people are actually using waste materials to make new products, or are reusing materials over and over again, keeping them out of the landfill. Also, as new materials are developed, people (engineers!) are working on new ways to make products from their waste materials. A good example is polar fleece, a relatively new material made from waste plastics. Important point we can only recycle our waste because there is a market for the waste. Companies want to buy our waste paper, metal, plastic, etc., because they are going to make products with them or use them as some kind of input to what they do. Engineers are the ones who come up with the ideas of ways to reuse these waste products. d. Brainstorm with the students about additional things that they, themselves, could make using different waste materials, to solve our problem. Lead toward building materials -- what kinds of building materials are there? What kinds of building materials can we make out of recycled materials? What kinds of building materials can we make in this classroom? Concrete Write the term concrete on the board. 3. (5 min) generate discussion about concrete. OK so now we ve got a new problem to investigate concrete! a. What do we know about concrete? Who has made concrete? How did you make it? What did you put in it? What have you made out of concrete? Where do you see concrete everyday? When you look closely at concrete what do you see in it? b. What don t we know, or what do we need to find out about concrete? Do we know what is in concrete? How much of each ingredient do we put in? How do we make concrete strong enough to make a bench (planter)? Have you seen sidewalks crack? How do we keep our product from cracking? 4. (5 min) Introduce need for research

24 a. How are we going to find out the answers to all these questions? Where can you go to look up answers to these questions? The library and WWW are both good sources for information on concrete. We will be going into the computer lab (or using notebooks of materials) to research answers to our questions, and some additional questions that we think are important for you to answer. b. Introduce World Wide Web and its advantages and disadvantages There are many advantages to the World Wide Web. For example, it is seemingly endless in the amount of information it contains. Sometimes information can be obtained faster than by other methods. For almost every advantage of the World Wide Web there are disadvantages. For example, even though there is a large amount of knowledge it is often hard to find. Unlike a library, it is poorly organized; there is no card catalog to go to. It is difficult to tell how reliable a source is on the Web because anyone can make a web page, and put almost anything they want on it. 5. (5 min) Concrete research Assignment a. Handout research worksheets and assign students into groups. Students may be asked to find as much information as possible, or assign one of the 5 categories of questions to each group (if you only have 2 days for this assignment, assign each group to find answers to one category, and if they finish let them continue with other questions). b. Inform students that they will be presenting their answers to the rest of the class (particularly good if you have each group do one set of questions). Provide overheads for them to write their answers on for the presentation. c. Read through the directions on the worksheets with the students. Ask students if they understand the directions. d. Let students begin the computer work, if there is time, and assign the rest of the web research as homework students are to try and find internet access outside of the classroom, and to complete as much of the assignment as possible. e. Remind students that they will share their answers the following day with the rest of the class. 6. Wrap up: Conclude lesson by reminding students: a. We brainstormed and identified a solution to our problem add waste products to concrete. Next we have to learn more about this solution to make additional decisions about our solution. b. We will go over the entire worksheet next lesson to fill in the questions that the other groups worked on. Encourage students to learn more about concrete at home on the WWW or in the library in their free time.

25 Lesson 3 Concrete Research 1. Background Narrative Students will research concrete topics on the internet, and then share the information they have gathered on their group s concrete topic with the entire class. By the end of the lesson students should have a good grasp of the information covered in each concrete research topic. This will give students a very good basic understanding about how concrete is made, tested, and some of its physical properties. This information sharing can be done quickly by having students just read their answers while other students fill in their blanks, or if an assessment is desired, groups could prepare overheads of the answers to their sections and get up in front of the class to share their information. If this is done, students should get a copy of the grading rubric that will be used so they know what is required. Major Concepts: Concrete A heterogeneous mixture of cement, water, and aggregate. 1. Cement The glue that holds the concrete together. 2. Fine Aggregate - Generally consist of natural sand or crushed stone with most particles ranging in size from to 6.5 mm. 3. Course Aggregate - Any particles greater than 4.75 mm, but generally range between from 6.5 to 38 mm in diameter. 4. Water Reacts with the cement to start the hardening process of the mixture. Hydration The hardening of concrete through a chemical reaction of cement with water. Curing The period of time that the concrete is left to harden. Compressive strength - Is tested by pouring cylinders of fresh concrete and measuring the force needed to break the concrete cylinders at proscribed intervals as they harden. Pounds Per Square Inch (PSI) The unit used to measure the compressive strength of concrete. 2. Performance objectives Standards: Students will be able to determine what information is relevant to understand, from the gathered information, in order to solve our problem. Students will be able to answer questions about each concrete topic, using the knowledge gained from group discussion. NYS 2.1, 2.2, 5.3, 5.5 US Sci: 2.3 US Tech: 1.3, 3.2, 4.1, 5.4

26 3. Resources Key Concept Worksheet Student Research Worksheets, along with the answer key Blank overheads 4. Instruction plan 1. (5 min) Introduction: Since maximizing discussion time is important for this lesson the introduction should be kept short. Simply recap what you told the students last lesson about what they are to do today. Explain that we will go through the work sheet in its entirety and the group that researched a given topic will be responsible for explaining the answers to those questions to the class (either just saying the answers or preferably standing in front and presenting the answers on an overhead), while the rest of the class writes down the answers on their own work sheet packets. Also explain that students will be given a grade based on student participation in class discussion, and correctness and completeness of group answers. (provide rubric if used) Remind students that they will be tested on this material at the end of the unit, so they need to record the answers! 2. (15-20 min) Computer time: Allow the students approximately 15 minutes on the computers to finish up any loose ends, and to give those students who could not obtain Internet access outside of the classroom a chance to participate. Students who finished the questions in their section are encouraged to surf the web to find information on other sites. 3. (10-15 min) Following this work period, instructors should facilitate discussion by asking the questions on the research worksheet and writing the correct answers on the blackboard or overhead (having students come up to write their answers on the overhead, or letting each group make a short presentation with their information, takes longer but is a good way to keep them engaged if it s possible to do). Throughout discussion keep students focused on relevant material. As each question is addressed, ask a different member of the designated group to provide an answer this way every student is required to provide and answer for the benefit of the class if there are more students than questions in a group, ask for alternate responses and compromise on the answer. 4. Hand out key concept worksheet: If time permits go over the key concepts worksheet with the students and ask if there are any questions about it. Tell students to save these! Inform them that there will be a test at the end of this unit over this material! 5. Wrap up: Review what the students learned a. they now know about the ingredients in concrete (cement, water, sand and gravel cement and water critical for making concrete, sand and gravel really just fillers to reduce the cost - cheaper than cement). b. They ve used the web as an information resource was it effective? Was it quick? c. Tomorrow learn more about aggregates and how we can use waste materials for aggregate.

27 Concrete Research Key Concepts Name Clarkson Partnership Date Key Concepts: The ratio of water to cement in most concrete mixtures is about 0.5:1 by weight. For example, if you used 2 pounds of cement in your concrete you would need to add 1 pound of water to your mixture. In most concrete mixtures sand is used as a fine aggregate and pea stone is used as a course aggregate. During the curing process concrete gains most of its strength. Concrete hardens due to hydration. Hydration only occurs if there is enough water to react with the cement. For this reason concrete needs to be kept wet during curing, by frequent watering and covering with wet cloth or plastic to hold in moisture. Concrete is usually tested after 7 or 28 days of curing. By the 28 th day the concrete has gained most of its strength. Concrete s strength is most commonly tested by compression, and measured in PSI.

28 Concrete Vocabulary: Concrete A heterogeneous mixture of cement, water, and aggregate. 1. Cement The glue that holds the concrete together. 2. Fine Aggregate - Generally consist of natural sand or crushed stone with most particles ranging in size from to 6.5 mm. 3. Course Aggregate - Any particles greater than 4.75 mm, but generally range between from 6.5 to 38 mm in diameter. 4. Water Reacts with the cement to start the hardening process of the mixture. Hydration The hardening of concrete through a chemical reaction of cement with water. Curing The chemical process required for the hydration of cement. This process takes a period of time, which is referred to as curing. Compressive strength - Is tested by pouring cylinders of fresh concrete and measuring the force needed to break the concrete cylinders by applying compression at proscribed intervals as they harden. Pounds Per Square Inch (PSI) The unit used to measure the compressive strength of concrete.

29 Concrete Web Research Look through this website to help you answer the questions below: [We created a webpage that has all the web links to the concrete sites - to eliminate the need for students needing to type the url addresses saves lots of time!] If your group finishes your section try the extra credit or find the answers to some of the other questions. Also feel free to help other groups out that are having trouble finding answers to their questions. Group 1. Cement and Concrete 1. What is the difference between concrete and cement? 2. What is the name of the chemical reaction that takes place in concrete? 3. What are the two ingredients that take part in this reaction? 4. There is more than one type of cement, list the name and type of the most common form used for general purposes.

30 Group 2. Concrete Mixture 5. What four ingredients do you mix together to make concrete? 6. Approximately what percentage of concrete s volume is made up of coarse aggregates, fine aggregates, and cement? 7. What is the best water-to-cement ratio to use to make strong concrete? 8. Explain the Rule of 6 s for mixing concrete: Group 3. Aggregates 9. What are the approximate sizes of coarse and fine aggregates (in mm)?

31 10. Give an example of each type of aggregate: 11. What happens to concrete if the aggregates are not clean? 12. What percentage of the concrete s volume is taken up by the aggregates? Group 4: Curing 13. What is curing? 14. What temperature range is ideal for curing? 15. What chemical reaction happens during curing?

32 16. Will concrete cure underwater? Why or why not? Group 5: Testing 17. What is 28-day strength? 18. How long does it take for concrete to reach its greatest strength? 19. What unit of measure is used to describe concrete s strength? 20. What would be a good strength for concrete? 21. What test do we usually perform to test concrete s strength?

33 Extra Credit 22. Search for recycled waste materials in concrete. Can you name 2 waste materials that people have used to make concrete? 23. Describe 2 benefits of using waste materials instead of sand and gravel in concrete.

34 Concrete Web Research List of Websites (2004): For the instructor: Note: before doing this activity, check the websites to see that they are still current! Categories Topics covered: Cement- types (I-V), difference from concrete, reaction with water (hydration) Aggregate- Fine, course Curing- how, length of time, temperature, under water? Mix What recipe, Method of 6, 1:3:4, homogeneous mixture Testing Compression, Normal PSI strength Weathering- Hot & Cold, deicers, Air Entrained Note: If you need to make some groups larger than others, make groups 1 and 2 larger, there is more information in their topics.

35 Concrete Web Research KEY Group 1. Cement and Concrete 1. What is the difference between concrete and cement? Cement is the glue that holds concrete together. Although the terms cement and concrete often are used interchangeably, cement is actually an ingredient of concrete. Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. 2. What is the name of the chemical reaction that takes place in concrete? Hydration is the chemical reaction that occurs in concrete. 3. What are the two ingredients that take part in this reaction? a. Cement b. Water 4. There is more than one type of cement, list the name and type of the most common form used for general purposes. Type I is a general purpose portland cement suitable for most uses Group 2. Concrete Mixture 5. What four ingredients do you mix together to make concrete? Cement Coarse aggregate Fine aggregate Water 6. Approximately what percentage of concrete s volume is made up of coarse aggregates, fine aggregates, and cement? 11% Cement 41% Coarse Aggregates 26% Fine Aggregates

36 7. What is the best water-to-cement ratio to use to make strong concrete? About 0.5:1 by weight 8. Explain the Rule of 6 s for mixing concrete: A minimum cement content of 6 bags per cubic yard of concrete, A maximum water content of 6 gallons per bag of cement, A curing period (keeping concrete moist) a minimum of 6 days, and An air content of 6 percent (if concrete will be subject to freezing and thawing). 3. Aggregates 9. What are the approximate sizes of coarse and fine aggregates (in mm)? Coarse (4.75 mm, but generally range between from 6.5 to 38 mm in diameter) Fine (most particles ranging in size from to 6.5 mm) 10. Give an example of each type of aggregate: Coarse: Pea Stone, crushed rock, gravel Fine: Sand 11. What happens to concrete if the aggregates are not clean? For a good concrete mix, aggregates need to be clean, hard, strong particles free of absorbed chemicals or coatings of clay and other fine materials that could cause the deterioration of concrete. 12. What percentage of the concrete s volume is taken up by the aggregates? Aggregates account for 60 to 75 percent of the total volume of concrete. 4: Curing 13. What is curing? Curing is the period of time that the concrete is left to harden. 14. What temperature range is ideal for curing?

37 After concrete is placed, a satisfactory moisture content and temperature (between 50 F and 75 F) must be maintained. 15. What chemical reaction happens during curing? Hydration is the chemical reaction that occurs during curing. 16. Will concrete cure underwater? Why or why not? Yes, concrete will cure underwater. Portland cement is a hydraulic cement which means that it sets and hardens due to a chemical reaction with water. Consequently, it will harden under water. 5: Testing 17. What is 28-day strength? The time period of 28 days was selected by specification writing authorities as the age that all concrete should be tested. At this age, a substantial percentage of the hydration has taken place. 18. What unit of measure is used to describe concrete s strength? Concrete s strength is measured in pounds per square inch (PSI). 19. How long does it take for concrete to reach its greatest strength? Concrete will reach its ultimate strength after several years. 20. What would be a good strength for concrete? 3,000 4,000 PSI is a good strength for concrete. 21. What test do we usually perform to test concrete s strength? Compressive tests are typically preformed to test concrete s strength.