Transcript 48x36 poster template - University of Cincinnati

Engineering Design: Bridge Building
Michael
1
1
Starr ,
Tamara
2
Jonson
College of Engineering, University of Cincinnati, Cincinnati OH; 2 Withrow University High School, Cincinnati, OH
Activity
Abstract
Bridges have been essential for transportation and moving
of people and goods throughout the history of man. Means
of crossing waterways have been practiced since the dawn
of civilization, as water is essential to life. The advent of
bridges allowed easy access for people on opposite sides of
rivers and waterways to conduct commerce, exchange of
ideas and many other activities that have accelerated the
development of technology in the human race. The process
of working with each other to accomplish a task aimed at
improving the living of humans is the essence of
engineering. By working in groups to design the most
structurally efficient, lightest and cost effective bridge the
students will be engaging in the most fundamental of ideals
of engineering.
Assessment Results & Feedback
Initial Activities: Learning About Truss Systems
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Pre/Post Assessment:
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QuickTime™ and a
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Objectives
• Identify members of a truss system as being in
compression or tension and it is possible for some
members to experience no load.
• Use trial and error for improving the design of a supportive
structure using both physical and computer models.
• Use basic drafting skills to create a scaled planar drawing
of simple structures.
• Work as a group on an engineering project and complete a
bridge structure from design conception to completion.
Activity where students built cubic
structures out of tooth pics and
observed how cross-members
served as support beams to
reinforce the structure
Students used a computer
simulation program to draw the
given structures in order to find
the state of stress in the circled
member as well as the value in
that member as well as the other
members of the truss system.
Geometry and Spatial Sense:
11-12 Benchmark A: Use trigonometric relationships to verify and
determine solutions in problem situations.
Students learned basic drafting
skills in order to draw a 1:1 scale
drawing of their bridge design so
that assembly could be done
directly on top of their drawing,
with wax paper down of course!
Mathematical Process:
11-12 Benchmark I: Communicate mathematical ideas orally and in
writing with a clear purpose and appropriate for a specific audience.
Ohio Standard: Science
Physical Sciences:
11-12 Benchmark D:
Apply principles of forces and motion to
mathematically analyze, describe and predict the net effects on objects or
systems.
Scientific Inquiry:
11-12 Benchmark A: Make appropriate choices when designing and
participating in scientific investigations by using cognitive and manipulative
skills when collecting data and formulating conclusions from the data
• Students averaged a score of 89.4% on the video questions
• Average score on pre-assessment was 58.3% with a low of 15%
and high of 95%, no post assessment done because students did
not complete their part of the lesson in time.
Reflections
State Standards
Ohio Standard: Mathematics
• Series of questions aiming to determine the students ability to
recognize when a beam is in compression or tension given a set
of parameters
Working in groups students made their
designs come to life by assembling their
bridges using pine dowel rods (round and
square) and basal wood.
Note: Poor time management from both the teacher/fellow and students as well as general lack
of motivation led to the bridges not being done in time for the competion and the bridges were
never tested :(
• I had hoped to teach the students about all the aspects of a
design project starting with brainstorming and research, then
figuring a budget based on a finalized design idea decided upon
by the whole group. They would have to compare their original
budget to their final cost of construction.
• What happened was students did not understand nor did they
want to put much effort into making a budget. Being there only 2
days a week made it hard to get them to do this on their own. I
think a good approach would be to one day use an example
bridge and go through with the class how to calculate a budget
for building that particular bridge, then the next day letting them
do their own budget.
• If you are assigning a cost to materials for budgeting purposes
setup a good system for a lumber yard or whatever, because I
had trouble keeping track who had taken what even with a table
due to my limited availability during the week.
• Though bridge testing was never done, myself and the students
seemed to have gained some insight from this lesson.
Acknowledgments
• Project STEP is funded through NSF Grant # DGE058532.
• Prof. Anant Kukreti for his guidance as my STEP advisor.
• Andrea Burrows for taking photographs of the activity.