WEST POINT Presents TEAM AMERICA

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2 WEST POINT Presents TEAM AMERICA Concrete Canoe Team 2005

3 WEST POINT TEAM AMERICA TABLE OF CONTENTS Name Page Executive Summary i Hull Design 1 Analysis 2 Development & Testing 3 Project Management & Construction 5 Organization Chart 6 Project Schedule 7 Design Drawing #1 8 Design Drawing #2 9 Appendix A: References 10 Appendix B: Mixture Proportions 11 Appendix C: Gradation Curves and Tables 12 EXECUTIVE SUMMARY The United States Military Academy at West Point is situated in prime canoeing territory 50 miles north of NYC in the scenic Hudson Valley. From this historic ground, tread by world famous patriots: Washington, Grant, Eisenhower, Patton, MacArthur, and many others, comes an equally outstanding group of young patriots. Team America was formed not only to preserve the liberties of the free world, but also to design an innovative concrete canoe to be explained in detail on subsequent pages. West Point is a four-year undergraduate institution. It produces commissioned officers for our United States Army and also intelligent engineers, as it is among the top undergraduate Civil Engineering Programs in the country. West Point has a 30 year history of participation in the ASCE CCC at a competitive level. Team America is 19 5 long, 2-6 wide, and 1-3 deep. The hull is on average ¾ thick and Team America weighs in at approximately 264 lbs. The concrete strength is approximately 815 psi at 28 days with a unit weight of 59 pcf. It is reinforced with steel Hardwire and is a rich black color with gold lettering. The concrete mix uses an innovative aggregate composite of multiple grades of polystyrene resins, 3M glass microspheres, and very low-density heat expanded polystyrene. The hull dimensions were designed by the team and incorporated into a very complex and laborintensive female style mold. The mold was constructed using precise cross-sections surfaced with thin wooden strips, spackle, four layers of paint, and generous applications of form-release agent. During casting, the team used a template to roller-compact concrete strips, ensuring a uniform thickness throughout the hull. Finished with West Point and the Army s colors black and gold it presents a formidable opponent for any competitor. i

4 WEST POINT TEAM AMERICA 1. Hull Design TEAM AMERICA is proud to present West Point s first ever computer-aided hull design for this year s Concrete Canoe Competition. This year marks the 30 th anniversary of the West Point Concrete Canoe Team program, and this is the first time that a West Point canoe was molded from an original computer created design and not from an actual canoe. While this meant more work and venturing into uncharted waters, TEAM AMERICA was up to the challenge. Our hull design is based on commercial canoe dimensions as well as recommended dimension ratios as specified in naval architecture literature (Gillmer and Johnson 1982). The desired range versus our actual design ratios can be seen below: Table 1.1. Design Geometry. Hull Geometry Length 20' Beam (width) 2' 6" Depth 1' 3" Volume 34.71ft 3 Surface Area ft 2 Max Displacement lb Design Draft*** 9" ***Based off design of 4 inches of freeboard Table 1.2. Design Considerations. Design Considerations Our Design Recommended Length/Width Ratio to 12 Length/Draft Ratio 28 7 to 30 Beam/Draft Ratio to 4 Our canoe was specifically designed to be long and sleek, with our canoe length being longer than those canoes produced by West Point in previous years. This is based on the concept of hull velocity, which is a function of wavelength and waterline length (Gilmer 1975). By making our canoe long and sleek, it increases the wavelength of waves the canoe produces, thus increasing its potential speed. Also, by using the naval architecture ratios of length/beam, length/draft, and beam/draft we were able to ensure our canoe was designed with sound engineering principles. In order to design the canoe efficiently, TEAM AMERICA used the software program Maxsurf, which is used by ship builders for projects ranging from sailboats to nuclear submarines. While the program was initially difficult to use, the tutorial quickly made the design user friendly. Figure 1.1. Plan view of TEAM AMERICA. TEAM AMERICA WEST POINT Figure 1.2. Elevation view of TEAM AMERICA. By using Maxsurf we were able to generate cross sections at specified intervals and then to plot full-size cross sections. Also, Maxsurf gave us the capability to plan for the amount of reinforcing and mix that would be needed for construction by providing important geometric calculations. Finally, the program calculated important hydrostatic relationships which helped validate our design. Figure 1.3. Cross Sectional View of TEAM AMERICA s hull. 1

5 WEST POINT TEAM AMERICA 2. Analysis 2.1 Hull Analysis The first design goal for the hull was to ensure that the design strength was greater than the required strength for all limit states, including positive and negative moment flexure, shear, punching shear, and plate bending. Positive bending moment creates the greatest potential for cracking. Our second goal was to limit cracking by ensuring the hull was compression-controlled (net tensile strain in steel, ε t, less than at nominal) for positive moment in accordance with ACI , In order to achieve our goals, we iterated the thickness and reinforcing configuration until our design goals were met. We selected Hardwire-3X2-4WPI mesh reinforcing for use in our hull. The Hardwire had the following properties: yield stress of 60 ksi, elastic modulus of 30,000 ksi, and 4 strands of wire per inch of mesh. We also conservatively assumed the compressive strength of our concrete to be 800 psi with a unit weight of 62.4 pcf. Using the computer program Visual Analysis, we constructed an equivalent beam that would model the size of thirty different cross-sections of the canoe over its 20-foot length. We modeled the canoe cross-sections as idealized U-Shapes with differing moments of inertia. After constructing the equivalent beam, we modeled three different load cases on the canoe. The first load case modeled the canoe in the water with four paddlers. We placed four single point loads of 200-lbs at even intervals along the canoe, as shown in Figure lbs 200 lbs 200 lbs 200 lbs Figure 2.1: FBD of hull with passengers. Canoe Self-Wt Buoyancy Force 2 The next two load cases modeled the hull as a simply supported canoe (carried by a person at each end) supporting its own selfweight. One load case modeled the positive moment, and the other modeled the negative moment. The two are equal and opposite; loading is shown in Figure 2.2. Figure 2.2: FBD of hull with self-weight. Canoe Self-Wt Required punching shear, normal shear, and local bending moment were all calculated using a column footing analogy. We modeled a rower s two knees as a 10-inch square column with a maximum load of 200 lbs. We assumed that the base of the hull would act as the footing. The results from Required Strength calculations are presented in Table Design Strength The design strengths for positive and negative moment were calculated in accordance with ACI , using the technique of strain compatibility and internal force equilibrium. The normal shear design Strength is taken from ACI , punching shear design strength is from ACI , and local bending moment is from ACI Results of the design strength calculations are summarized in Table 2.1. Table 2.1: Summary of Design and Required Strengths. Steel Strengths Strain (in/in) Design (ΦR n ) Required (U) Positive Moment ft-lbs ft-lbs Negative Moment ft-lbs ft-lbs Local Bending ft-lbs 31.5 lbs Normal Shear lbs 82.2 lbs Punching Shear lbs lbs In conclusion the final canoe design, with ½ inch of thickness and 1 layer of Hardwire, meets our design goals for all five limit states.

6 WEST POINT TEAM AMERICA 3. Development and Testing The primary focus of the development was on the concrete mixture itself. Our team identified the concrete mix as the controlling aspect which dictated the other facets of design (i.e. reinforcement, hull design). The goal concrete mix must be both stronger than 800 psi and less dense than water. Reinforcement must then be selected which will increase the tensile and flexural strength of the canoe as determined by the hull analysis. 3.1 Concrete Mixture Development Aggregate - The 2005 concrete mixture was driven by the requirement of aggregate to be graded within the bounds of ASTM C33 for fine aggregates. In addition to meeting the grade requirement, properties desired for the aggregate composite are: relatively strong, does not crush or deform with mixing, easily obtainable, and lighter than water to counter-act the higher density of binders within the mix. Many aggregates tested, including charcoal, perlite, and sawdust, removed water from the paste due to their absorptive properties, increasing the density and resulting in very little or no workability in the concrete. Some of these aggregates, more specifically perlite, was often pulverized during mixing, becoming more dense, absorptive, and non-compliant with the ASTM C33 gradation. Other conventional lightweight aggregates and sands, though very strong, were not used because there was little that could be done to reduce the density of the mix to something competitive. The final composite aggregate was a blend of three sources; 2 grades of unexpanded polystyrene resins (65% by weight), expanded polystyrene beads (26% by weight), 3M type S1 glass micro-spheres (9% by weight). During aggregate development, we encountered many difficulties due to properties inherent in our selections. We had negated the effects of absorption by choosing entirely impermeable aggregates. The polystyrene resin was obtained from Huntsman, a manufacturer and marketer of commodity and differentiated chemicals. The manufacturer provided no data regarding the specific gravity for unexpanded solid resins. Through multiple tests, it was determined to have an approximate specific gravity of 1.1. The next aggregate used was a byproduct of heating the solid resin. We attempted various methods of expanding the polystyrene, the first of which was boiling. It was very easy to boil the solid resin and achieve a consistent result. Unfortunately, they were difficult to work with when moist and created unpredictable mix designs. Finally, cooking the dry resin in a convection oven at approximately 110 degree Celsius gave us a product which was always free of moisture and easy to work with. The specific gravity of the expanded polystyrene was approximately Cement - Binders were chosen in adherence to option 3 in section of the NCCC rules. It consists of 51% Type III Portland Cement, 16% fly ash, and 26% ground-granulated blast furnace slag, with the addition of 7% silica fume in order to increase strength. In the past, silica fume had not been used because it significantly reduced workability in already dry mixes. However, this year, due to the properties of the aggregates, we were able to incorporate it into the mix design with effective results. Admixtures - Admixtures were used very sparingly in the mix design, but were necessary for multiple functions. Admixtures from Grace Construction Products were graciously donated and used in our design. Most importantly, we added 6 fluid oz. of Daratard 17 per hundred pounds of cementitious materials (fl.oz./cwt). It served primarily as an initial set retarder with the secondary effects of increased plasticity, increased strength, and decreased permeability. Finally, ADVA flow, a super-plasticizer, was added at a dosage of 0 2 fl. oz./cwt. The quantity was adjusted dependent on the requirements of the casting team and the required workability of the concrete for different parts of the canoe. Iteration After finding a desirable proportion of paste/aggregates, we established a baseline and sought the most beneficial proportion of aggregate types in adherence to 3

7 WEST POINT TEAM AMERICA C-33. The goal was to maximize the use of the very strong unexpanded polystyrene while using minimum amounts of expanded beads necessary for concrete less dense than water. The proportion used was 1 part expanded to 3 parts unexpanded. At this proportion, the unit weight of the concrete was less than that of water and this was used as the baseline mix on which very few changes were made. Mixes were tested and evaluated based on 7-day compression tests using 2x4 inch cylinders, and in accordance with ASTM C-39. They were then refined as necessary. 3.2 Reinforcement Materials Low density, high strength materials were ideal for reinforcing the concrete canoe. They are needed to add significant tensile strength to the hull and to allow for better performance under flexural loading and the rigors of competition. Below are the reinforcements considered. Table Reinforcing Properties. Yielding Load (lb) Cross- Sectional Area (in 2 ) Yielding Stress (ksi) CCX, Fiberglass Mesh TechFab, Carbon Fiber CT300 Grid Hardwire, 3X2, 4WPI* *Hardwire data based on Manufacturer s Specifications. All others based on pure tension tests. For the 2005 design we had planned to use high strength steel Hardwire reinforcement along the length of the canoe at the bottom and at the gunwales where tensile stresses would be the greatest. In addition to the Hardwire, the CCX lightweight fiberglass mesh would serve as our reinforcement in the lateral direction. However, during canoe construction, the mesh was substituted with additional Hardwire. The CCX mesh proved too difficult to lay-out in the form and too fine to effectively work into the concrete. The result is an over-reinforced canoe in the transverse direction in no danger of cracking or failing, with a slightly heavier weight. 3.3 Plate Sample To validate our reinforced concrete composite, a plate sample was cast and tested. A sample of the Hardwire mesh was cast into a composite sample approximately ¾ inches thick. The sample, tested with a single point load with a clear span of 7 in., supported a 600 lb load before cracking. In addition, the composite sample was successfully load tested with a 170 lb person post-cracking. The composite plate sample, which reflects the properties of the as-built canoe, passed the load test without failure in shear or bending. In addition, the cracking moment of 87.5 ft-lbs exceeds the required moment expected in the plate, based on the analysis results in Section 2, Table Final Canoe Properties The final concrete contains approximately 40% cement paste by volume. The average unit weight is 59 pcf. Compression tests on the baseline concrete mix have yielded strengths of greater than 1000 psi with an average of approximately 950 psi, however, a conservative value of 800 psi was used for all design calculations. Cylinders cast from batches used in the construction of the canoe were tested at 7 and 28 days. Tests on 2x4 inch cylinder samples at 7-days yielded an average compressive strength of approximately 700 psi, with 28-day tests at approximately 850 psi. The canoe is reinforced in each direction with a separate layer of Hardwire-3x2-4WPI mesh. Approximately 4.5 cubic feet of concrete was used to cast the canoe, contributing to its final weight of 264 lbs. 4

8 WEST POINT TEAM AMERICA 4. Project Management and Construction 4.1 Organization TEAM AMERICA s organization was critical to our success. We were assisted in our efforts by our project advisor, Major Marvin Griffin. Additionally, Lab Technician Lynden Crosbie s expert advice was instrumental during the construction. The cadet members of the team were divided as follows with the following responsibilities: Matt Kern was chosen as the team captain and also the primary concrete developer. He worked on this project during both semesters of academic year Bobby Petska, who had also worked on this project both semesters, became the structural analyst. Greg Ambrosia was took charge of researching and creating the optimal hull design. Bryan Smith became the supply/logistics expert and coordinator. Nick Cahill was the team s construction manager. Team members Beth Wagner and Meghan Vrabel worked with finishing the canoe. Responsibilities were assigned to team individuals based on their own personal skills. Weekly meetings were kept so that all team members would be involved in all parts of the process. Because all of these responsibilities were far more than one individual could reasonably handle, all teammates contributed in some capacity to each of the other s duties. 4.2 Critical Path A very broad critical path was determined as follows: finalize canoe design, construct mold, cast canoe, and finish canoe. However, as these milestones were taking place, several other efforts were underway. Designing concrete and analyzing the hull occurred simultaneously and were completed prior to casting. This critical path was based on the competition date. We allowed the canoe 28 days to cure with at least 1 week to finish, so we had to cast at least 35 days prior to April 9 th, the date of the regional competition. Subsequent backwards planning gave us our timeline. Over the two semesters team members have contributed approximately 430 man-hours. This is a best estimate taken from time surveys kept by the team and covers all facets of the project through the end of the regional competition and submission of this document. 4.3 Construction Our team decided upon a female mold in hopes of achieving a smoothly finished canoe of uniform thickness. With the expert assistance of Lynden, our lab technician, and MAJ Griffin, our advisor, we discussed and agreed upon a form design, the necessary materials for it, and the timeline we would follow. Strips of Luann plywood, ¼ inches thick, were nailed to cross-sections at 8 intervals. The mold was then spackled, sanded, painted with several coats of primer and lacquer, and finally waxed with form release Partall Paste. We constructed the mold with a breakable joint in the center of the canoe which would allow us to simply slide the form from beneath the canoe. In order to place uniform layers of concrete, we constructed a ¼ inch deep by 4 foot long rectangular template out of plywood. We then placed wax paper into the template and rolled concrete onto the paper. Next we picked up both ends of the wax paper and placed the concrete sheet of uniform thickness onto the canoe mold. We continued this process over the entire surface of the canoe, patching any areas as needed. Both layers of reinforcement were worked into thin layers of concrete and then a final layer of concrete was added. During curing, the canoe was covered and kept moist with the aid of humidifiers, burlap, and a vapor barrier. When finishing the canoe, we decided upon our school colors, black and gold. The black stain was diluted according to the manufacturer s recommendations with 1 part rubbing alcohol to 1 part dye to ensure compliance with the rules, and applied in two coats. Finally we added a water-based acrylic curing and sealing compound also in two coats. These two steps would hide any imperfections on the surface of our canoe as well as provide the background for our gold lettering. 5

9 CADET TEAM MEMBERS: Greg Ambrosia Nick Cahill Matt Kern Bobby Petska Bryan Smith Meghan Vrabel Beth Wagner TEAM AMERICA ORGANIZATION TEAM MANAGER Matt Kern Coordinates with faculty and delegates tasks Faculty Advisor MAJ Marvin Griffin Lab Technician Mr. Lynden Crosbie Development Construction Structural Analyst Bobby Petska Perform analysis of loads on hull and develop hull thickness Hull designer Greg Ambrosia Assign canoe dimensions, design cross sections Construction Manager Nick Cahill Plans form construction, coordinates with Lab Tech. provides experience Molds/Frames Nick, Greg, Matt, Bobby, Bryan Construct and finish forms and prepare for canoe casting Support Bryan Smith Manage finances and supplies, coordinate orders, research materials Design Paper Greg, Matt, Bryan, Bobby, Nick Concrete Engineer Matt Kern Research aggregates and materials, develop mix, ensure compliance, and test Casting Nick, Greg, Matt, Bobby, Bryan Mix and place concrete, reinforcement, and ensure proper conditions during curing process Competition All Team Members Row, Give Oral Presentation, Have Fun! GO TEAM AMERICA Finish Canoe Nick, Greg, Matt, Bobby, Bryan, Meghan, Beth Sanding, sealing, staining, detailing 6

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11 4 TEAM AMERICA QTY Item Description x8 plywood sheet Platform x4 x8 Framed Base x8 ¾ Plywood 8 INTERVALS BETWEEN CROSS SECTIONS x8 1/4 Luan Laths All Purpose Joint Compound (gal) Spackle White Latex Primer (gal) Waterproof B 5.0 Lacquer Spray (can) Shell Coating TEAM AMERICA WEST POINT 1 3 LUAN STRIPS RUNNING TO PLYWOOD X- SECTION 0.5 Partall Paste #2 (gal) Form Release Wax B MOLDED CANOE REV. DATE REV NO: Engineer: G. AMBROSIA Drawn By: G. AMBROSIA Date: 3/10/05 CONCRETE AND REINFORCING Checked By: MAJ GRIFFIN Date: 3/10/05 PLYWOOD X- SECTION (FEMALE MOLD) 2 6 SEC. B-B 2x4 BLOCKING Job Name: TEAM AMERICA Page 8

12 TEAM AMERICA QTY. Item Description x2 4WPI (ft 2 ) Hardwire Reinforcing 4.0 Concrete (ft 3 ) Concrete 1 Stain (gal) Waterproofing 1 Sealer (gal) Waterproofing 20 B TEAM AMERICA WEST POINT 1 3 Canoe thickness: ¾ ; Two layers of reinforcing running perpendicular, the inner layer running parallel to the length of the canoe and the outer layer running perpendicular to that. REV. DATE REV NO: 0.75 in B 2 6 Engineer: G. AMBROSIA PLYWOOD CROSS SECTION 15 Drawn BY: G. AMBROSIA Checked BY: MAJ GRIFFIN Date: 3/10/05 Date: 3/10/05 SPACE Job Name: TEAM AMERICA CONCRETE HARDWIRE MESH SEC. B-B Page 9

13 WEST POINT TEAM AMERICA REFERENCES ACI (January 2002) Building Code Requirements for Structural Concrete. Farmington Mills, MI. ACI 318R-02 (January 2002) Commentary. Farmington Mills, MI. ASTM (2001). Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens. C 39/C 39M-03, West Conshohocken, PA. ASTM (2001) Standard Specification for Concrete Aggregates. C 33-03, West Conshohocken, PA. Gillmer, Thomas C. and Johnson, Bruce. (1982). Introduction to Naval Architecture, Naval Intsitute Press, Annapolis, pp Gillmer, Thomas C. (1975). Modern Ship Design, Naval Institute Press, Annapolis, 1975, pp MacGregor, J.G., Wight, J.K. (2005). Reinforced Concrete: Mechanics and Design, 4 th Ed., Prentice Hall, New Jersey, Chapter 4, pp and Chapter 16, pp Maxsurf Software, Formation Designs Systems. < (January 10, 2005). Paradis, Francois and Marc Jolin (August 2004). "Want to Build a Better Canoe?" Concrete International, 26(8), PREVIOUS YEAR DESIGN PAPERS Knowles, John et al. (2004) Concrete Canoe Design Paper: Milwaukee School of Engineering. Pierce, Shannon. Project Manager (2004) Rock Solid: Concrete Canoe Team University of Wisconsin Madison. Walker, John and Beck, Adam. Captains. (2004) The Rock United States Military Academy. Yeldell, Sarah. Project Manager (2004). ConQuest: The Quest Continues The University of Alabama at Huntsville. A-1

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