For Goodness’ Cake

Concrete Canoe Design Paper New Mexico Tech 2016 For Goodness’ Cake

Table of Contents Executive Summary…………………………………………………………………… (Page ii)

Project Management …………………………………………………………………..(Page 1)

Project Management Resource Allocation ………………………………………….(Page 2)

Organization Chart …………………………………………………………………….(Page 3)

Hull Design and Structural Analysis …………………………………………...(Pages 4 & 5)

Development & Testing ……………………………………………………..(Pages 6, 7, & 8)

Construction …………………………………………………………………….(Pages 9 & 10)

Project Schedule ……………………………………………………………………..(Page 11)

Construction Drawing ………………………………………………………………..(Page 12)

Appendix A: References……………………………………………………………..(Page 13)

Appendix B: Mixture Proportions………………………………………….....(Pages 14 & 15)

Appendix C: Example Structural Calculation ……………………………….(Page 16 & 17) List of Figures Figure 1 – Critical Path…….………………………………………………………… (Page 1)

Figure 2 – Person Hours………………………………………………...…….…….. (Page 2)

Figure 3 – Budget…………………………………………………………………..… (Page 2)

Figure 4 – Internal Moment………………………………………………………….. (Page 5)

Figure 5 – Internal Stresses……………………………………….………………… (Page 5) List of Tables

Table 1 – Canoe Properties……………………..…………………………………… (Page ii)

Table 2 - Materials………………………………………………………………….…..(Page 7)

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Executive Summary The New Mexico Institute of Mining and Technology is a small, public school located in Socorro, New Mexico. Our campus was founded in 1889 as the New Mexico School of Mines (with the “technology” moniker eventually being added in 1951 for relevance and marketing purposes). Our school currently teaches 2127 students, but only a small fraction belongs to the Civil/Environmental Engineering department. As a result, the Civils are a tight-knit group, and class sizes in the single digits are not uncommon. While entertainment in Socorro is notoriously absent, most students need a steady supply of free time to keep up with New Mexico Tech’s infamously challenging curriculum. In regards to the project itself, our canoe’s theme was inspired by the delicate proportioning and near-culinary nature of mix design. Our team members are but humble concrete bakers, and the canoe is our window display of concrete deliciousness: a cake canoe.

For the past three years, our school has both competed in the ASCE Rocky Mountain Student Conference’s Competition, and performed dismally in each attempt. 2013 Results: 12th/12th place, 2014 results: 12th/12th place, 2015 results: 9th/11th place. Despite this, our team has taken past performances and recommendations from former students as a foreshadowing of the difficulty of the project, and is determined to be competitive in 2016. This year’s team consists of 6 seniors who have selected this competition as their senior design project, and all design parts of the project are to be completed exclusively by these team members.

As of the writing of this paper, the canoe mold is currently being constructed, with pouring to occur shortly afterward. The concrete properties and dimensions provided are based on projected values based on our mix and volumetric design.

Table 1. - Canoe Properties Concrete Density: 44lb/ft3 Flexural Str.:83.7psi Canoe Name: For Goodness’ Cake Weight: 228 lbs Wet Unit Wt. : 44lb/ft3 Max Width: 2’ 7”

Color: Dark Medium Grey Dry Unit Wt. : 39.96lb/ft3 Max Length: 20’

Max Depth: 14” Primary Reinforcement: Chicken wire 28-day Strength:557.8psi Secondary Reinforcement: N/A Tensile Str. : 70.9psi Avg. Thickness: 1"

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For Goodness’ Cake Project Management Our team began the planning stages of the canoe in the fall semester preceding this year’s competition. Our team consists of 6 members; each design task was split evenly among the members based on both working knowledge of the activity, and personal interest. For each major task, a single group member would be selected as leader, and allocate tasks to other group members.

$1500(the majority of our team budget) was generously donated by New Mexico Tech’s student affairs office. The ASCE club also fundraised $167 for the project. As detailed in the material allocation section, local hardware stores and batch plants donated a large portion of our mix’s required materials. As a result, we were able to complete the canoe for well under our initial budget, without compromising the quality of our mix design.

Before working in the lab, our faculty advisor had the canoe group attend a lab safety meeting with the machine shop operator at New Mexico Tech, who taught about proper safety precautions while working in the civil engineering lab. As a minimum requirement, safety goggles, long pants, close-toed shoes, padded gloves, and respirators were taught to be worn at all times. These precautions were shown to be especially important when mixing concrete, as fine dust particles or caustic mixtures pose a considerable safety threat. Regardless, almost all lab activities have some level of inherent risk, and safety in the laboratory was our number one priority.

Figure 1 – Critical Path

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Project Management

Figure 2 – Person Person Hours Allocation Hours This figure shows how the person Project Management*, hours were assigned on this project. Most 80 Canoe of the time is spent in Fabrication*, 120 construction and in team meetings.

Note that the “*” Hull Design, 22 activities are not Structural completed and Analysis, 8 estimates are used in their place. Mix Design, 42 Mold Construction*, 80

Anticipated and Actual Expenditure 1200

1000

Figure 3 – Person 800 Hours This figure shows where it was 600 anticipated that Anticipated ($) money would be 400 Actual ($) spent, and the actual spending. A large 200 quantity of the material was donated, which dramatically 0 helped to reduce cost.

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Organization Chart

Aaron Baukus (Sr.) Richard Cottrell (Sr.) Antonio Gallegos (Sr.) Project Manager Finances Design Paper Hull Design Design Paper Mix Design Structural Analysis

Amanda Lozoya (Sr.) Michael Sanchez (Sr.) Derek Sobol (Sr.) Construction Mix Design Transportation Aesthetics Structural Analysis Engineer’s Notebook

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Hull Design and Structural Analysis Through the entirety of our team’s volumetric design, our goal was to create a lightweight and maneuverable canoe that would last for years to come. The most important aspect of our canoe was ensuring the harmony of mold design and mix design.

We engineered the hull cross section to provide a balance between speed, tracking and turning capabilities. These design parameters were chosen by analyzing the qualitative design decisions of our predecessors: La Culebra (2015) and Old Prospector (2012). The angular profile of La Culebra’s hull made for excellent tracking; however, rendered turning nearly impossible. In addition, the blunt entry line caused the vessel to move at below-average speeds. Old Prospector’s shallow-arched hull allowed for exceptional maneuverability, however, the canoe’s wide beam resulted in increased resistance against the water. This year, our group hoped to take the strengths in design from both canoes and apply them to our design. Overall, these observations resulted in reducing the canoe’s frictional resistance by reducing surface area, and optimizing the hull’s geometry for ideal maneuverability.

To reduce the frictional resistance and maintain stability, a shallow arch hull profile was selected. More importantly, the canoe’s beam dimensions were reduced in order to further reduce the wetted surface. Additionally, the angle of entry to the water surface was reduced, and medium rocker was added to the bow. This will decrease the wetted surface of the canoe and therefore reduce the frictional resistance.

To improve the canoe’s maneuverability, we designed the stern region to be more angular, with a greater amount of deadwood than the rest of the canoe. This angularity will enable the back of the canoe to turn more slowly than the front, allowing for sharper turns. Our initial plan was to design the canoe cross section with a tumblehome profile in order to allow rowers easier access to the water’s surface. The design’s constructability was called into question once an early mix design was revealed to be very runny. The consistency of the watery mix does not bond well to the curved profile and, as a result, the canoe was designed to have a flared profile.

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Hull Design and Structural Analysis To complete the structural analysis, the canoe was modeled as a simple beam statically supported by the buoyant force. A rectangular shell cross section was chosen to represent the canoe’s cross section due to the deep depth and shallow wall slope at the midsection. Excel was chosen as the program for analysis for its ability to quickly calculate tables of values, and output graphs.

As mentioned above and detailed in example calculations presented in Appendix C, the canoe is modeled as a beam acted upon by the concrete self-weight, 4 rower point loads, and the buoyant force. Knowing the overall weight of the canoe, the distributed load of the concrete self-weight was found to 1.243lb/in. Since the canoe is considered to be in equilibrium, the distributed buoyant force was found to be 3.99lb/in.

Once all of the loads were determined, the Figure 4. Internal Moment Diagram internal shear and moment were calculated along along the length of the canoe the changing length of the canoe. Then, using the moment values, the depth of the neutral axis, and the calculated moment of inertia, changes in stress values were determined and are presented in figure 4.

The line on the top of the graph represents the compressive loading in the upper sections of

the canoe, and the lower line represents the Figure 5. Stress vs position graph for tensile forces in the bottom of the canoe. The the longitudinal span of the canoe maximum compressive force was found to be 180psi, and the maximum tensile force was found to be 47psi. These values - which are already conservative due to the simplified nature of the assumptions made to ease calculation - are well within the expected parameters of the chosen concrete design mix.

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Development and Testing Having competed in the competition for many years, each consecutive year’s canoes have gone through several attempts at innovation. Our school’s first attempt at innovation in 2009 was a low-riding profile, along with a mix that yield a density of 55 lb/ft3 with a compressive strength of 980psi (lb/in2). Our next canoe would be created two years later in 2011, which had a density of 52lb/ft3 and a compressive strength of 1100psi – a much more efficient design. Then from 2012 - 2015, New Mexico Tech would create a series of canoes that would venture off into trying truly unique mixes that sought to obtain durability, the lowest density, and the least wetted surface with the water. Unfortunately, some of these mixes proved to be unpredictable in terms of buoyancy, some canoes presented delamination problems and some of the unique shapes didn’t partake the look of a typical canoe.

The greatest lessons this year’s team learned from were from last year’s team (2015). Last year’s canoe weighed approximately 400lbs with poraver and as the main strength-providing materials. Last year’s team also used a comparatively high amount of portland to bind extra strength-promoting materials in the mix. While our predecessor’s mix design yielded a compressive strength over 2000 psi, the mix’s density was larger than water’s pinnacle value of64 lb/ft3. The resulting canoe had trouble on the swamp test, and all the extra weight proved to be a challenge to even carry across campus at the conference.

During last year’s canoe construction, a fibrous mesh was used as the main source of tensile reinforcement. The mesh, however, had a very small cell size, which caused the two layers of concrete surrounding the mesh to bond poorly. The first layer of concrete dried up so quickly that the second layer had trouble binding due to the mesh’s open area not being large enough for the aggregates to pass through. With all of these issues accounted for, this year’s team aims to improve upon last year’s successes, and hopes that New Mexico Tech will perform better than it has before.

The first goal was to create a mix that had a lighter density than last year’s mix (our goal being 40 – 55lb/ft3),while aiming for a reduced compressive strength (our goal being a 28-day strength of 350 – 500 psi). This year’s mix consisted of each of the

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Development and Testing following: type I/II, Poraver 1mm-2mm, , Sand, Latex 3701, and Water with a mix density of 44lb/ft3(Table -1). Table 2 discusses the reasons why these materials were used, and presents potential drawbacks.

Table 2. -Materials Purpose of Using Material Cautions with Use of Materials

Portland Cement - Type I/II ● Binds with admixtures ● Requires a precise ● Improves strength amount of water

Fly Ash ● Replaces Cement ● Fly ash’s benefits range ● Improves workability, from 10 - 30 % of enhances strength gain replaced concrete

Poraver1-2mm ● Fine aggregate ● Expensive ● Very low density

Latex - Additive 3701 ● Water resistant ● Needs time to properly ● Increased bond and cure, approximately 14 compressive strength days to

Sand - Raks Supply ● Coarse Aggregate ● Densest material ● Improves binding of mix ● Can Clump Our final mix was acquired through extensive research, including the creation of numerous cylinders run through concrete compression tests (ASTM E9-09). At the beginning of our research phase, the mixes yielded results that were very undesirable. We recorded densities ranging in the 80-90lb/ft3, and mixes that yielded disproportionate water/cement ratios. To illustrate this trend, our first mix, which consisted of 12.353lb of cement with 3.84lb of water, used poraver as the main aggregate in the mix. The resulting mixes tended to have great compressive strength approaching 2400psi, but the resulting unit weights were well above that of water (some as high as 76 lb/ft3). The team’s response was to reduce all of the dry ingredients in hopes of reducing the density at the expense of the mix’s excessive strength.

Despite the usage of latex to increase tensile strength (based on a recommendation from former students), our team decided to use chicken wire as a form of primary reinforcement. Since our mix design was much lighter than previous years, the team was fearful that without a form of primary reinforcement heavier than a fibrous mesh, the canoe would not be able to withstand heavy forces exerted by multiple rowers. Using a manufacturer’s estimation of the tensile strength and loading properties

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Development and Testing For the galvanized chicken wire in our canoe, we learned that chicken wire doesn't lose strength if a section is cut off. Also, we learned the plaster layer and reinforcing metal layers in the wire adjust to the temperature with varying values of thermal expansion coefficients. The galvanized chicken wire we were researching was also found to be available at a local hardware store, and also was very cheap. These economic and availability factors weighed heavily on our decision, as last year’s team had difficulty acquiring the fibrous mesh reinforcement they had design for before their scheduled concrete pour date.

To address the concern that the walls of the canoe would not have enough to prevent pullout of the chicken wire, the primary reinforcement was only used in the bottom section of the canoe. The bottom section also experiences the highest loads (established from our structural calculations in Appendix C as well as intuition) making primary reinforcement most essential in that area.

To test this primary reinforcement, our team created samples of our final mix design, and placed two layers of concrete around a section of wire. After a two week curing period, we observed how the concrete bonded to the material, and noted how the mix reacted when tensile force was applied to the wire.

Another reason why the team favored chicken wire as a tensile reinforcement is due to the fact that it can easily bend to different angle surfaces while being mounted down(ASTM A390, 2011). Since the mold was designed to consist of 20+ Styrofoam pieces, the team could safely connect each piece and create the desired shape of the canoe without fighting a stiff reinforcement layer.

To conclude, during development and testing of our mix, safety was our number one priority. By developing a habit of safety procedures and positively encouraging safety practices to others working in the lab, we hope to establish a high safety standard for future canoe teams.

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Construction The mold of our canoe was constructed primarily from cross-sections of Styrofoam cut to the dimensions of our volumetric design. Prior to construction, the dry ingredients of our concrete mix were pre-proportioned in 3-gallon dry-mix bags, to later be mixed with water and placed immediately to avoid excessive setting.

The foam selected is1.5 PCF foam, made of EPS (expanded polystyrene).The 1.5 PCF EPS foam was selected for its durability, as the concrete will be relatively heavy and any deformations in the foam will show up as obvious flaws in the canoe. Secondly, the foam was selected for its small grain size. The grain size of the foam directly relates to both the smoothness and accuracy of the final mold. While it is possible to sand down the concrete to achieve both the desired smoothness and correct dimensions, starting with a canoe as close as possible to the designed values will greatly reduce the work required to finish the canoe’s surface. Most importantly, however, the foam we purchased was found to be locally available and relatively inexpensive, which was ideal for our budget and schedule. After purchasing, the foam was divided into 20 cross-sections, marked according to our volumetric design, and cut with standard handsaws.

Our school’s teams have used male molds in the past, and having seen the success in pouring over previous years, we decided to use a male mold for this year’s canoe as well. This has many advantages: first, ease of construction, as a male mold requires removing material from the outside of the mold. Since we will be using a convex shape, it will be far easier to cut the mold away than the interior concave shape required by a female mold. Secondly, due to the stiffness of the concrete as it is being poured, it is far easier to ensure a uniform thickness of the canoe with a male mold as the entire surface is accessible to be smoothed out. Finally, due to the limited space allowed by our construction lab, we opted for a more streamlined male mold, instead of a bulkier female mold.

Prior to pouring the concrete, 3-gallon “cake mix” will be filled to contain all of the dry materials of our concrete mix in pre-measured amounts. Each bag will then be

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Construction mixed with a calculated weight of water just prior to construction to create approximately 3 gallons of concrete needed to pour the canoe. The choice to use pre-made dry mixes

was primarily an effort to speed up construction of the canoe, and to ensure that all of the concrete could be applied to the mold before any of the concrete started to dry. We calculated that 47 mix bags would be required to pour the entire canoe.

To summarize the overall pouring plan, the first step will be to make a very large batch of concrete in the civil lab’s electric concrete mixer. This large batch will be placed on the mold all at once to ensure the layer sets evenly. The second step will be the preparation of the chicken wire sections to be laid between two major batches of concrete. By having a pre-measured section of chicken wire, we will simply lower the chicken wire onto the first layer of concrete before the first batch can set excessively. The third stage will involve multiple concrete batches being produced at the same time using the pre-proportioned bags mentioned previously. The second batch will be mixed 2-3 gallons at a time by mixing the dry ingredients with the appropriate amount of water from our mix design. The resulting small batches will sum to create the overall second batch/layer for the canoe.

The canoe was poured with a team of approximately 20 students from New Mexico Tech, primarily recruited from the ASCE club as a volunteer activity. The cake mix bags will be produced in a similar manner, with an “assembly line” measuring and adding each ingredient. The mixing, pouring, and finishing of the concrete will be overseen by the canoe team and our faculty advisor. Two canoe team members will play a specific role: safety manager and quality assurance manager.

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Appendix A: References

ASTM C143 / C143M-15, Standard Test Method for Slump of Hydraulic-Cement Concrete, ASTM International, West Conshohocken, PA, 2015, www.astm.org

ASTM A390-06(2011), Standard Specification for Zinc-Coated (Galvanized) Steel Poultry Fence Fabric (Hexagonal and Straight Line), ASTM International, West Conshohocken, PA, 2011, www.astm.org

ASTM E9-09, Standard Test Methods of Compression Testing of Metallic Materials at Room Temperature, ASTM International, West Conshohocken, PA, 2009, www.astm.org

Canoe Design. Canoeing.com Ltd, 2013. Web.

Part 1. The Motor Boat: Devoted to All Types of Power Craft. Vol. 19. N.p.: Motor Boat, n.d. N. pag. Print.

Winters, John. The Shape of the Canoe Part 1: Frictional Resistance. Green Valley Boat Works. N.p., n.d. Web.

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For Goodness’ Cake Appendix B: Mixture Proportions

CEMENTITIOUS MATERIALS

Specific Volume(ft3 Component Amount (mass/volume) (lb/yd3) Gravity ) Cement, ASTM C150 Mass of all cementitious 3.15 0.951 c: 186.966 materials, cm 3 207.8lb/yd

Fly Ash, ASTM C618 2.7 0.124 m1: 20.821 c/cm ratio 0.743

FIBERS

Specific Volume(ft3 Component Amount (mass/volume) (lb/yd3) Gravity ) Ultra-Fiber 500, ASTM 1.1 2.74E-09 f : 0.24 C1116-08, D7357-07 1

AGGREGATES

Base Quantity (lb/yd3) Batch Quantity MC ( Volume, Aggregates Abs (%) stk SG (at MC ) %) SSD (ft3) stk OD SSD (lb/yd3) Poraver, ASTM A :20 0.5 0.583 W :167.8 W :201.4 4.61 W :176.2 C330, C331, 1 OD,1 SSD,1 stk,1 C332

Sand A2:5 0.4 1.6 WOD,2:41.5 WSSD,2:43.5 0.42 Wstk,2:43.1 ADMIXTURES

Dosage Admixture lb/gal % Solids Water in Admixture(lb/yd3) (fl.oz/cwt) Total Water from Latex 3701, 16.8 x :250 s : 0 w :68.2 All Admixtures ASTM C1438 1 1 admx,1 68.2lb/yd3

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For Goodness’ Cake Appendix B: Mixture Proportions

SOLIDS (LATEX, DYES AND POWDERED ADMIXTURES)

Component Specific Gravity Volume(ft3) Amount (mass/volume) (lb/yd3)

Latex 3701, ASTM 1.083 0.266 S1:67.92 C1438

WATER Amount (mass/volume) (lb/yd3) Volume(ft3) Water, ASTM C1602, lb/yd3 w:120.837 1.94 Total Free Water from All 3 ∑w :0.2 Aggregates, lb/yd free

Total Water from All Admixtures, 3 ∑w :67.92 lb/yd admx 3 Batch Water, lb/yd wbatch:52.7 DENSITIES, AIR CONTENT, RATIOS AND SLUMP cm fibers aggregates solids water Total Mass of Concrete, 207.7 0.24 219.3 67.92 52.7 M:547.86 M, (lb, for1 yd3 ) Absolute Volume of Concrete, V, 1.075 2.74E-09 5.03 0.266 1.94 V:8.311 (ft3) Theoretical Density, T, (= M / 65.92 lb/ft3 Air Content [= (T – D)/D x 100%] 33.2 % V) Measured Density, 44.01 lb/ft3 Slump, Slump flow 7.0 in. D water/cement ratio, water/cementitious material ratio, 0.83 0.743 w/c: w/cm:

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Appendix C: Example Structural Calculations

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Appendix C: Example Structural Calculations

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