THE SPAGHETTI BRIDGE The goal of this competition is to develop a bridge that will carry as much weight as possible, yet weigh as little as possible, while meeting all of the requirements listed. The bridge design should achieve the highest efficiency possible. The material that is to be used is #9 spaghetti (thin), which is to be supplied by the teacher. The structure must be three-dimensional and capable of fitting in the testing jig provided. Maximum points for the fabrication portion of the grade will be awarded for the lightest structure that will support the load. Bridges failing will be graded on the bridge’s structural efficiency (E). E=Max load supported/mass of the bridge. Students will work in groups of no more than three and all in the group will receive the same grade (unless the group evaluates a member differently.) It is expected that the work will be shared equally. In addition to the fabrication of the structure, each person will submit a one to two page report that will include all design drawings and calculations. Students will also research bridge designs on the Internet and find one that fits their needs for the contest. A bridge building program will also be used to construct and evaluate compression and tension members of the bridge design. The bridge building program will help students with efficiency evaluations. Research: Students can use books, magazines, and the library, to research bridge designs. The Internet will be used to find a web site that explains and demonstrates bridge styles and construction. The students should include this information in printed form and attach to their report. West Point Bridge Building Program: Student will make a drawing of the style of bridge they have selected. The program will show compression and tension members and how strong they are. A cost analysis and efficiency rating will be used to help students design and build their spaghetti bride. Drawings: A 2-D AutoCAD drawing and a 3-D inventor drawing, assembly, balloon drawing and presentation file, of the whole bridge. The front elevation and side elevation of the 3-D drawing will be printed out and used as a pattern for the spaghetti bridge. The spaghetti can be cut exactly to the right size by laying it down on the drawing and cutting it. Details about construction of the bridge: Only spaghetti may be used for construction of the bridge. Any adhesive may be used to join the ends of the spaghetti. Longitudinal gluing may not be allowed. Hot Glue works very well. No part of the bridge may extend more than ¾” below the support elevation. The bridge length must be 15 long. A hole must be provided in the center of the bridge to allow for the threaded rod. It is suggested that this area be strengthened to accommodate the point load. The roadway must have an opening in it to allow a 1" thick by 2" wide x 6" long testing block to slide through. The jig will be weighed and included in the weight on the bridge. The bridge cannot weigh more that 100 grams. Width of the bridge is 2.5 to 4.0 inches No height requirement of total ht. Testing Procedures: The bridge will be centered on the supports. A bucket will be attached to the center support and the load will be applied. The student will add sand to the bucket until failure occurs. Maximum time for loading will be 5 minutes. The weight of the filled bucket will be massed and used in the efficiency formula. Failure of the bridge is defined as the inability of the bridge to carry additional load without breakage or sagging more that 1 cm below support elevation. The Report: PROPOSAL REQUIREMENTS Format Requirements: I. Typed II. Double-spaced III. 12-point font (Arial or Times New Roman) IV. All pages on 8.5 by 11-inch paper V. Information must be in the same order as shown below VI. All pages numbered Proposal Components: I. Title Page. Include name of challenge, team name and logo, name of school or organization, name of team captain and team members, and name of teacher or advisor. II. Table of Contents. III. Introduction. a. Describe what special skills were learned or demonstrated. IV. Body. The main part of the report. b. Explain the reasons behind the design of your bridge. c. Explain the scientific principles supporting the design of your bridge. d. Include data tables and graphic representation of tests. e. Include supporting calculations. f. Include 8.5 x 11-inch scaled drawing of the bridge using AutoCAD software and Inventor Do not crop or use the print screen option when printing the drawing. g. Explain how you tested your design, and the improvements you made as h result of the testing. i. Describe the problems you encountered in designing and building your bridge and how you solved these problems. j. List and describe any special tools or machines that were used to design and/or build your bridge. VI. Conclusions and Recommendations. l. How successful is your project? m. What did you learn by taking part in the bridge challenge? n. Describe any recommendations you have to improve your bridge or the bridge challenge competition. IX. Bibliography. o. List all references used, including internet, books and magazines. X. Appendices. aa. Working Drawings. Include working drawings not contained in the design section. bb. Additional Supporting Information. Grading: Research information Accuracy Bridge/drawings AutoCAD Drawings 2-D of Side View 3-D Drawing Inventor West Point Bridge Program Drawing Efficiency rating of Bridge Report Team Grades each persons work +Total points possible Time line (approx): Research West Point Building Program 3-D Drawing Construction of Bridge Report (on own time) Graphs and other Efficiency rating of Bridge 1st 2nd 3rd 4th place place place place 50 40 30 20 points points points points 1 4 3 5 day days days days 1 day 10 points Individual 25 points Individual 25 points Individual 25 points Individual 20 points Individual 50 max See Schedule below 35 points Individual 20 points Individual 200 points