Suspension Workshop
Alexander Aptekar
Architectural Technology & Library /
LEARNING PLACES: UNDERSTANDING THE CITY
Activity Description: Provide a brief description of the activity
In this workshop, you will work in teams and groups of teams to create a model suspension bridge. Your model suspension bridge will be tested until structural failure. In reflections, you will individually analyze the strengths and weaknesses of your modeled suspension bridge.
Learning Goals: What do you aim to achieve with this activity?
• Developing your understanding of suspension structures
• Increasing your analysis and problem-solving abilities
• Sharpening your observation and reflection skills
• Deepening your collaborative team techniques
Timing: At what point in the lesson or semester do you use this activity? How much classroom time do you devote to it? How much out-of-class time is expected?
This workshop should occur towards the beginning of the semester as part of the introduction to observation skills and techniques.
Logistics: What preparation is needed for this activity? What instructions do you give students? Is the activity low-stakes, high-stakes, or something else?
Low-stakes
Each team will utilize the following kit of materials:
• Wood blocks (4” x ¾” × ¾”), 18 min
• String, 8’ lengths
• Straws, 14
• Sheets of paper, 3 @ 4” x 17”
• Scissors
• Masking tape, 3’ length
• Tape measure (only one for the workshop required)
Team goals
Construct a model of a suspension bridge utilizing only the materials provided. The bridge must be strong enough to support at least one cell phone at its center. [Recommendation; offer extra points for every additional cell phone the bridge can support]
Team makeup
Each bridge group will consist of two 3 to 4 member teams. Each team is responsible for one half of the bridge spanning from one of the supporting tables to the center of the bridge.
Bridging the gap
Each bridge group will need to span between two tables set 36” apart.
Bridge assembly
The bridge constructed should include the following parts:
• Anchorage (blocks)
• Deck (paper)
• Main cable (string)
• Suspender cables (straws)
• Tower (blocks)
Timing
Your bridge group will have 20 minutes to develop your solution before testing will commence.
Testing
The structural integrity and quality of your bridge will be tested by checking to see how many cell phones the bridge will be able to support. The class will observe as each bridge is tested. Be ready to document where and what are the causes of structural failure. At 20 second intervals, additional cell phones will be added to the Main span of the bridge until the bridge collapses. [It’s recommended that students be ready to catch their cell phones and have their hands under the bridge at least 3 inches away from the bridge deck]
Assessment: How do you assess this activity? What assessment measures do you use? Do you use a VALUE rubric? If not, how did you develop your rubric? Is your course part of the college-wide general education assessment initiative?
Reflections /Documentation
Each team member will need to post on the Open Lab their reflections on this workshop. Be sure to include the following issues in your reflections:
• What strategy did your team used to solve the problem?
• Did you use the iteration process effectively?
• What were the hardest team organization challenges?
• What are the hardest technical challenges?
• What part of the bridge did you think would collapse first?
• What part did collapse first and why?
• Include at least two photographs, sketches or diagrams in your reflection.
Assessment
This assignment will be evaluated by reviewing your reflections on the Open Lab. The focus of this evaluation will be the lessons learned in this workshop. Additional points will be given for each cell phone your groups bridge could support.
Reflection: How well did this activity work in your classroom? Would you repeat it? Why or why not? What challenges did you encounter, and how did you address them? What, if anything, would you change? What did students seem to enjoy about the activity?
Following are some quotes from student reflections on this project. Additional reflections can be seen at this site:
https://openlab.citytech.cuny.edu/aptekar-berger2205sp2017/assignments/216-reflection-on-suspension-bridgeobservation-sketch/
“Today’s class project was very challenging and hands on. It is something I enjoyed doing because my team worked well together to create a steady bridge. Although, it took some time to figure out how to actually build a proper bridge was kind of difficult considering I know nothing about architecture or building. My team mates worked together from putting straws together to taking down blocks to the table. Overall, we learned that the anchorage is the most important part which is something our bridge lacked. Now we know for next time what to spend more money on.”
Alexandra Linik
“…
3. I learnt that the cabling is as important as the others structures as well. Since it is suspension bridge, both the weight of the deck and the live loads will be hung by the suspenders. So the connection between the horizontal cable and vertical cables should be strong enough to hold all the weights. And the angle of the cable from the anchorage should be calculated in order to reduce the extra forces.
4. Lastly, I think we can design our towers of the bridge more pretty, because I learnt that putting weights on the towers do not help in order to stabilize the bridge.”
Alice Myint
“In today’s class the most interesting and challenging part was to make a suspension bridge using small wood blocks, ribbon, tape, paper and our creative mind of course. I got to know some of my classmates whom I have worked with throughout the project. I think architectural stuffs sounds like easy, but it’s really not and the worst experience was when we made the bridge and it’s collapsed twice. But we did not lose hopes and we made a well -organized and furnished bridge with beautiful two anchorages and deck. The “deck” should be strong because the weight on the bridge is related on the base and it’s connected to the deck of both sides of the bridge. We put 4 phones on the bridge and it was still in the same position, but however it collapsed when 5th phone added on the bridge. But in the class we had much fun when working with as a group. We were very excited to see how others work done and that was the coolest part because we can learn something how they made their own. Overall, it was very cool, making a bridge with elementary stuffs and a great experience to work with my classmates.”
Mdzafar Sadak
“The class project that we have was pretty intresting because we get to work together as we form two group. One group was to build one half of the bridge and the other group would do the other half of it. The challageing part was trying to combine the bridge and form a deck that could support the weight. We through that it would help but as it turn out after we finish building it and testing it that it wasn’t the deck that we create can support the weight it was the anchor was the most important part of it that would have support the weight of it. The thing that i learn most was no matter what type of bridge that people make if the anchor is not strong enough then the whole bridge would fall.”
Alan Qiu
Additional Information: Please share any additional comments and further documentation of the activity – e.g. assignment instructions, rubrics, examples of student work, etc. These can be links to pages or posts on the OpenLab.
I welcome comments and suggestions. I am be happy to provide you with more documentation including diagrams and photographs for this workshop. Don’t hesitate to reach out by email.
Please share a helpful link to a pages or post on the OpenLab
