Table of. Contents. Appendices Appendix A: References... A-1 Appendix B: Mixture Proportions... B-1 Appendix C: Bill of Materials...

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2 Table of Contents Executive Summary... i Project Management... 1 Organizational Chart... 2 Hull and Structural Analysis... 3 Development and Testing... 4 Construction... 7 Project Schedule... 9 Design Drawing List of Figures Figure 1: Typical Canoe Meetings... ii Figure 2: OSHA Safety Card... 1 Figure 3: FEA Output Image... 3 Figure 4: Dry Cementitious Material... 4 Figure 5: Dry Aggregates... 5 Figure 6: Example section of cross section and bracing... 7 Figure 7: Completed Mold... 7 Figure 8: Finishing Techniques... 8 Figure 9: Spreading paste on final layer... 8 Figure 10: Final Unpainted Canoe... 8 List of Tables Table 1: Dimensions... ii Table 2: Concrete Properties... ii Table 3: Theoretical Strength Requirements... 3 Table 4: Design Properties vs Actual... 5 Appendices Appendix A: References... A-1 Appendix B: Mixture Proportions... B-1 Appendix C: Bill of Materials... C-1 i

3 Executive Summary Auburn University is a proud institution of more than 25,000 students and 6,500 faculty and staff. Continually ranked among the top 50 public universities nationally, Auburn is one of the South s largest educational institutions, offering more than 230 undergraduate, graduate, and doctoral degree programs. The Auburn University student chapter of the American Society of Civil Engineers was the first ASCE student chapter founded in the South, as well as nationally, and continues to be a leader in this area. Auburn s ASCE chapter consists of over 70 members and is growing each year. Auburn University s concrete canoe team is looking to build off a solid foundation created from last year s Canoe of Destiny. This year Auburn s concrete canoe team has worked tirelessly creating TIGERPILLAR. Using the skill learned from previous years, TIGERPILLAR hopes to be Auburns best concrete canoe thus far. TIGERPILLAR is themed after the construction industry, which many civil engineers aspire to be part of, and was created using a male mold. The mix was created by modifying a successful mix design from previous years. A paste was also created along with the normal mix in order to give the canoe a smooth finish. This was the first time this technique was implemented and allow for better aesthetics as well as an easier surface to paint on. The goal for this year s team was to uses successful innovations from previous years and expand on them in order to try and further Auburn University s concrete canoe team in the future. ii Table 1 -- TIGERPILLAR Dimensions Max Length (ft) Max Width (ft) Max Depth (ft) Average Thickness (in) Overall Weight (lbs) 230 Color Yellow and Black Table 2 - Concrete Properties Structural (with fibers) Unit Weight pcf Compressive Strength 1587 psi Tensile Strenght 285 psi Reinforcement Basalt Primary Reinforcement Reinforcement Mesh Figure 1: Typical Canoe Meeting

4 Project Management Organization and Leadership: The actual design and construction of the TIGERPILLAR was split into three main branches: hull analysis, concrete and materials, and construction. Each large division was headed by an experienced team member who divided tasks into individual or group projects. This organization style placed experienced members in a position to instruct less experienced members in a small group or one-on-one setting. It also allowed for parts of the team to work at different times and locations best suited to that group s individual tasks, and for some members to participate in multiple aspects of the design and construction. A graphical depiction of the organization structure can be found on page 7. Figure 2: OSHA Safety Card Remaining aspects of the project, such as the engineer s notebook and the project display, were assigned to individuals. These team members were in charge of ensuring the completion of all tasks not directly related to design and construction of the canoe itself. Regular weekly team meetings were held throughout the year to ensure all team members were familiar with overall progress and to facilitate intercommunication between project groups. Meetings also served to build a sense of team camaraderie among members. The team captain acted as the project manager, overseeing all aspects of the canoe from start to finish and keeping the team on task and schedule. He scheduled and led the weekly meetings and managed the financial aspects of the project. Scheduling: Scheduling is especially important to a project in which all the participants have other commitments that can conflict with the completion of tasks. Keeping in mind that fall semesters at Auburn University are always busy with football games and other events, most of the actual construction was not scheduled until late fall semester. The majority of the fall semester was planned to be used for research, design, testing, material procurement, and other more flexible tasks that did not require large blocks of time only available on Saturdays. A Gantt Chart of planned and actual scheduling can be found on page 2. Safety: Safety has always been an important concern of Auburn University and its concrete canoe team. Several team members have completed a 30 hour Construction Safety and Health Training Course as well as every team member completing the online safety quizzes required to compete at conference. At every meeting and during the construction of the canoe, proper safety measures were taken in order to protect team members. 1

5 Organizational Chart 2015 Project Manager Michael Giudici Consulted lead engineers, Coordinated with our faculty advisor, involved in all aspects of the project Faculty Advisor Dr. Justin Marshall Dept. of Civil Eng. Lead Engineer: Construction Michael Giudici Lead Engineer: Mix & Materials Michael Giudici Coordinated design and testing of all materials Naval Architect Michael Peck Researched and Designed Hull Structure and Geometry Facilities Stephen Crew Designed and built a new curing room Mix Design Eric Gross Researched materials, develop tested mixes Structural Engineer Andrew Calton Analyzed loads and stresses on the hull Mold Construction Samantha Dixon Planned Construction Techniques, Constructed and finished mold Display Samantha Dixon Safety Coordinator Kate Wehrfritz Report & Presentation Samantha Dixon Paddling Coach Stephen Crew Casting/Finishing All Team Members Mixed and applied concrete to mold using determined techniques, sanded, stained, and sealed the canoe Outside Consultants Dr. Anton Schindler Dept. of Civil Eng., Structures Dr. David Timm Dept. of Civil Eng., Materials Dr. Wesley Zech Dept. of Civil Eng., Construction Brian Freeman Radiance Technologies, Senior Eng. Billy Wilson Dept. of Civil Eng., Lab Technician Michael Giudici Stephen Crew Michael Peck Andrew Calton Shane Glover Heidi Schutzbach Engineer s Notebook Michael Giudici Team Roster Kate Wehrfritz Rebecca Nylen Samantha Dixon Brandon Cole Whitney Shannon David Kimbel 2

6 Analysis In the past few years, hull analysis has not been a high priority of the Auburn University team. This year s analysis was done in order to create a lighter canoe that was still structurally sound. By creating a new mold, this year s canoe team was able to take advantage of a new hull analysis. The success of the hull design of The Argonaut reinforced the decision to reuse previous years analysis models for TIGERPILLAR. This includes two main methods of analysis: a finite element analysis (FEA) and a traditional analysis. The traditional method modeled the canoe longitudinally as a beam. The beam was assumed to be made up of a uniform cross section consisting of an open top rectangle of 20 width (average beam) at the base, 12 height and a 3/4 wall thickness. Distributing a conservatively estimated dead weight of 300 lb. uniformly along the beam simply supported on each end, simulated the load condition the canoe would experience if two team members picked up the canoe at the bow and stern or on a display with supports at the bow and stern. Assuming a uniform stress distribution along the length of the beam, the flexure formula was applied to calculate the maximum tensile and compressive stresses assuming linear elastic behavior. The values are presented in Table 3 along with the results of the other analyses. Table 3 - Theoretical Strength Requirements Simple Beam Crosssection Model FEA Compressive (psi) Tensile (psi) Other load cases were considered; however, none of the other load combinations produced a higher maximum moment. Therefore, the scenario used in design was for the critical case described. A similar simplified cross-section was used to model the maximum stresses laterally. The base of the width of the rectangle was increased to (max beam). All the other dimensions remained the same. A hydrostatic pressure variation was applied to the walls and a constant hydrostatic pressure was distributed across the bottom. The water level was assumed to be even with the top of the cross-section. Assuming the force balancing the buoyant force has no effect on the maximum moment, the maximum moment was calculated. Again, the flexure formula was used to calculate the maximum tensile and compressive stresses assuming linear elastic behavior. Figure 3: FEA Output Image Additionally SolidWorks was used to import and run a FEA on the hull (see output in Figure 1). Several load cases were considered. The maximum normal stresses in the longitudinal and lateral directions were reviewed for each load case. 3

7 Development and Testing The mix design for the TIGERPILLAR was largely based on the mix design from two years ago. All but one of the same materials were used to save on costs, but the idea was to improve on that mix design to make the new canoe lighter. Three new mix designs were developed and test cylinders were made for each mix. The cylinders were tested under compression to ensure that strength was sufficient. Ultimately a mix design was chosen that has a lighter unit weight than several mix designs from previous years. Cementations Materials Lehigh type I-II cement was chosen due to previous experiences and to satisfy the requirements of ASTM C-150. The second cementations materials used was class Slag. The use of slag was new, and provided strength more quickly. The final cementatious material used was metakaolin. Metakaolin is a substitute for silica fume used in high strength concrete applications, especially where tensile strength is needed. Fibers Polypropylene (PP) fibers were chosen for their combination of elasticity, strength, and low density. The two main reasons for the addition of fibers were increased flexural strength and decreased shrinkage cracks during hydration. Polypropylene is highly elastic and strong, but unlike many types of fibers commonly used in concrete it has a density less than that of water. For this reason, PP fibers were chosen over other types of fibers. Figure 4: Dry Cementitious Material Aggregates By basing the new mix design on the mix design used two years ago, the aggregates that would be used were already determined. These aggregates included 3M K-1 glass bubbles, varying sizes of Poraver glass microspheres, and crushed recycled glass bottles. Initial test batches utilized a combination of crushed recycled glass bottles, K-1 glass bubbles, and glass microspheres. This combination was used as the starting point because it was the obvious choice given the constraints and success of past mix designs. The only way to make this combination of aggregates yield a low density concrete was to use a large amount of 3M K-1 glass bubbles. When large amounts of this material are used in a mix, the concrete becomes too dry because of the high water demand of the K-1. It also reduces the strength of the concrete. Because of this increased water demand, 4

8 a workable and durable concrete mix of this type would need to have much less K -1. The next set of mixes consisted of crushed recycled glass bottles, K-1 glass bubbles, and microspheres of varying size. Initial test batches proved that using K-1 and glass spheres as aggregates would be an ideal way to achieve a light unit weight without sacrificing too much strength. Combinations of crushed glass bottles, three different sizes of microspheres, and K-1 were tested to find a gradation that combined strength, workability, and low density. A picture of a dry mix batch is presented in Figure 4. Admixtures No admixtures were used in this mix design. In previous years water reducers were included in the Auburn University mix design. However, water reducers were not used in older mix design or this year s. Since density was an important aspect of the mix design, the volume of K-1 was increased slightly. Water reducer was not used because it created a concrete with too much slump. Figure 5: Dry Aggregates Reinforcement Two types of reinforcement were utilized on TIGERPILLAR. The primary reinforcement is a basalt mesh and the secondary reinforcement is fifty pound test Spider-wire fishing line. Table 4: Design Properties vs Actual Required From Attribute Analysis Actual Compressive Strength (psi) Tensile Strength (psi) Spider-wire is a braid of gel-spun polyethylene fibers with a very high tensile strength for its diameter. The primary reinforcement was placed between the layers of concrete. An innovation of the Thumbs Up canoe team, secondary reinforcement was weaved through the mesh and pulled taught. The purpose of the secondary reinforcement is not to add strength; although some extra strength may be achieved, the additional strength is relatively negligible. The main purpose of the secondary reinforcement is to hold the primary reinforcement in place and remove wrinkles during construction. Testing Concrete: Initial testing comparing aggregates was done using mortar cubes (ASTM C 109). The base-line test for concrete was compressive testing of 4 by 8 cylinders (ASTM C 39). Tensile strength testing was done using 4 by 8 cylinders in indirect tension (ASTM C 496). The 5

9 results of these tests helped the team gauge the effectiveness of the mix and make adjustments. Changes and improvements of mixes were tracked using Excel spreadsheets developed by the 2006 team. A comparison of actual strength to design strength is presented in Table 4. Reinforcement: Testing was done on 1" by 6" sections (five strands per 1" in length and seven strands per 1" in width directions) of the polyester mesh. On average, the reinforcement carried pounds per inch in the length direction and in the width direction. After simple division, the pounds per strand come to 30.8 pounds per strand in the length direction and 18.1 pounds per strand in the width direction. Composite: Later in the design process, plates measuring 6 x 12 x 0.75 were constructed just as the canoe walls would be constructed. The plates were loaded in flexure to test the strength of the reinforced concrete in a mode that simulates the forces the canoe would experience. Innovation and Sustainability Innovation: Innovation: The process of altering past canoe designs had a focus on a lighter model in order to paddle more easily and efficiently. However, Canoe of Destiny proved to be less maneuverable than predicted. Thus, the goals for Tigerpillar included a new shape for better handling in the water, as well as a more consistent, durable blend of concrete. Concerning the mix for this year s design, a main ingredient was Glass Microspheres, which were used because of their light weight and how incredibly resistant they are to compressive forces in comparison to other lightweight aggregates. Furthermore, recycled glass is a large portion of Tigerpillar, used to improve the durability of the canoe and, of course, to provide a sustainable alternate to making concrete. To improve the shape for this year s canoe, an entirely new mold was constructed. This was done by changing the plan from an outer mold casing to an inner mold casing. This improved the technique for applying the concrete and also for removing the mold once cured. As these goals were met for the 2015 design, Tigerpillar, it is noted that the main goal is to provide students in engineering an opportunity to learn and appropriately compete against their peers using their skills, determination, and perseverance. This is represented by the canoe built and designed by those willing to work hard and appreciate ASCE and the Concrete Canoe competition. 6

10 Construction The goals for this year s mold construction team was to utilize the knowledge used from previous years and create a high quality male mold. The process started by taking the CAD drawing and plotting them full size on paper. The drawing were then attached to plywood allowing us to cut out each cross section by tracing over the printout. This ensured a high quality standard for each cross section. The cross sections were attached to 2x4 s running along the bottom. Wood strips were also used at various locations along the outside of each cross section to enhance the stability. Aluminum flashing was then laid over each cross section to provide a consistent contour. Flashing tape was put over the seams of the aluminum flashing to ensure a smooth finish. The mold was built in three sections and then screwed together to form one long section. We implemented this design in order to make it easier to remove the canoe from the mold. After the canoe was poured we were able to flip the mold over and unscrew the sections which allowed us to easily remove each section from the canoe without causing any damage. The canoe was poured in two different layers with basal mesh inserted between each. The concrete was placed by hand initially in order to form it to the mesh. Following this a trowel was used to create an even finish. The final layer consisted of a paste made of Figure 6: Example section of cross section and bracing Figure 7: Completed Mold 7

11 cementitious materials. This was used to create a smooth finish and fill in any low spots that were created earlier in the process. A curing room was built after the canoe was poured by connecting 2x4 s to the table we constructed and attaching plastic sheeting around the outside. A humidifier was installed in order to keep the room at a constant humidity. Also, two burlap sheets were placed over the canoe and sprayed daily to keep the canoe moist during curing. Figure 8: Finishing Techniques After the canoe was finished curing, we used a sanding stone to take out any bumps that were created during the curing process. Following this we painted the canoe with a sealer to prevent any leaks from occurring in the water. The final step was painting the canoe. TIGERPILLAR followed a construction theme, mainly Caterpillar, so we painted it black with a yellow stripe to match. Our logo and school name were then spray painted onto each side of the canoe. Figure 9: Spreading mortar on final layer Figure 10: Final Unpainted Canoe 8

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14 Appendix A: References ASTM (2007). Standard Specifications for Concrete Aggregates. C33-03, West Conshokocken, PA. ASTM (2007). Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens. C39-05, West Conshokocken, PA. ASTM. (2007). Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2 in. or [50 mm] Cube Specimens, C 109/C 109M-01, West Conshohocken, PA. ASTM. (2007). Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens C 39/C 39M-01. West Conshohocken, PA. ASTM. (2007). Standard Test Method for Splitting Tensile Strength of Cylindrical Concrete Specimens, C 496, West Conshohocken. ASTM (2007). Standard Terminology Relating to Concrete and Concrete Aggregates. C125-07, West Conshokocken, PA. ASTM (2007). Standard Test Method for Density (Unit Weight), Yield, and Air Content (Gravimetric) of Concrete. C138-01, West Conshokocken, PA. ASTM (2007). Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates. C139-05, West Conshokocken, PA. ASTM (2007). Standard Test Method for Slump of Hydraulic Cement Concrete. C143-05a, West Conshokocken, PA. ASTM (2007). Standard Specification for Air-Entraining Admixtures for Concrete. C260-06, West Conshokocken, PA. ASTM (2007). Standard Specification for Fiber-Reinforced Concrete and Shotcrete. C , West Conshokocken, PA. Auburn University, Concrete Canoe. (2009). Bubba Slump Canoe Co. NCCC Design Paper, Auburn University, Auburn, AL. Hibbler, R. C. (2005). Mechanics of Materials, 6th Edition. New Jersey: Pearson Prentice Hall. Hibbler, R. C. (2006). Structural Analysis, 6th Edition. Jersey: Pearson Prentice Hall. NCCC Rules (2015) American Society of Civil Engineers National Concrete Canoe Competition Rules and Regulations. Rules.pdf Solidworks. (2008) SolidWorks - 3D Mechanical Design and 3D CAD Software. A-1

15 Mixture ID: 2015 #1 THE MIX Cementitious Materials Batch Size (ft 3 ): Specific* Gravity Amount (lb/yd 3 ) B-1 Volume (ft 3 ) Amount (lb) Volume (ft 3 ) Amount (lb/yd 3 ) Volume 1. Portland Cement, Type I Fly Ash, Class F Vcas, Vcas, Total of All Cementitious Materials: Fibers 1. 8mm PVA Total of All Fibers: Aggregates 1. K-1 Glass Microspheres Absorption: 0.0 % Batched Moisture Content: 0.0 % mm Recycled Glass Absorption: 25.0 % Batched Moisture Content: 0.0 % mm Recycled Glass Absorption: 25.0 % Batched Moisture Content: 0.0 % mm Recycled Glass Absorption: 25.0 % Batched Moisture Content: 0.0 % mm Recycled Glass Absorption: 25.0 % Batched Moisture Content: 0.0 % Total of All Aggregates: Water 1. Total Batched Water Water Added for Agg. Absorption Total Water from All Admixtures Total Water: Solids Content of Latex Modifiers 1. SBR Latex Total Latex Solids: Admixtures 1. SBR Latex [SG = 1.55] lb Retarder [SG = 1.068] lb/g High Range Water Reducer [SG = 1.05] lb/g Wt./gal: Cement-Cementitious Materials Ratio Water-Cementitious Materials Ratio (w/cm) Slump, Slump Flow, in. (Flow Table, %) Design Air Content, % Density (Unit Weight), lb/ft 3 Gravimetric Air Content, % Yield, ft 3 % Solids Abs. = Absorption; MC = Batched moisture concrete; Non-SSD Proportions as Designed Amount (fl oz/cwt) Water in Admixture Actual Batched Proportions Amount (fl oz) Water in Admixture Water content of admixture. Yielded Proportions Amount (fl oz/cwt) ^ Including water added for aggregate absorption; If impact on w/cm is less than 0.01 enter zero. * For aggregates, provide ASTM C 127 oven-dry bulk specific gravity. (ft 3 ) Water in Admixture

16 Bill of Materials Material Quantity (lbs) Unit Cost ($) Total Price ($) Portland Cement, Type 1 92 Donated 0 Fly Ash, class F 49 Donated 0 Vcas, Vcas, Basalt 8 mm fibers K1 Glass Microspheres 4 Donated mm Recycled Glass mm Recycled Glass 22 Donated mm Recylced Glass mm Recycled Glass Retarder 9.60 lb/gal (Oz) 4 Donated 0 High Range Water Reducer 8.9 lb/gal (Oz) 13 Donated 0 Total Cost C-1