HELP! Suggestions for High School Structural Engineering Curriculum 11

[rrumer]

Hello Everyone -
I am an electrical engineer teaching high school Structural Engineering to Jr/Sr boys. Not all of them will be technical. I am really interested in what topics should/should not be included in the course. This is an exposure course that complements our Architecture class. We want to develop their interest in engineering and not overwhelm them.
Science: Physics-forces, moments, static equilibrium, Center of Mass, stability. Materials: stress, strain, strength, Young's Modulus, focus on steel, concrete, wood
Technology: Construction of houses: foundation, walls, flooring, trusses, etc. Lots of case studies and failures.
Engineering: Dead Loads, Live Loads, Snow, Wind, Earthquake, Structural Analysis and build of - beam, column, truss, bridge, tower. Stress/Strain/Shear/Moment/Deflection. Safety Factor
Mathematics: Nothing past Trigonometry and Logarithms
Previous Design/Building Projects: 1.) 20' diameter Geodesic dome (PVC), 2.) 16'x16' standalone wood deck.
Software: Using Fusion 360 (free, works on Mac) ... easy simulation of designs. Other free easy software suggestions?
Thanks in advance for your assistance!
Bob

 

[Agent666]

I'd focus on some case studies as well, why things collapsed and that sort of thing would be fairly interesting to high school kids. They'll learn something without even realising it.

Projests such as building structures out of some material and loading them up to failure would be fairly straightforward. I remember in first year university we were given a sheet of mdf and asked to build a structure to span between two points and it was tested to destruction with largest point load supported winning.

Also did one with iceblock sticks and small bolts and made trusses which also were tested to destruction.

Then try explain why some performed better than others, high level stuff, then give them the chance to do it again and hopefully you get some improvement in load carrying capacity!

 

[Agent666]

Maybe site visit to local University testing labs would be interesting, as they'll see some of the cool stuff engineers do.

 

[3DDave]

I would suggest a course around the book "To Engineer Is Human: The Role of Failure in Successful Design" by Henry Petroski. There is plenty of time for analysis and seeing how things work correctly, but less examination of the nature of failure and how smart people doing what seem to them to be the right things can go wrong.

I would also add in the TED Talk, "On being wrong" by Kathryn Schulz • TED2011 • March 2011

Finally a look at "The Visual Display of Quantitative Information" by Edward R. Tufte, which includes the famous and devastating image of Napoleon's downfall in his campaign into Russia, but also deals with why Shuttle Challenger was essentially destroyed by Powerpoint. I believe it also covers how an epidemic was resolved with a graphic that mere numbers would have hidden.

 

[IDS]

I strongly disagree with all the anti-computer comments.

Like it or not, computer analysis is now an integral part of the structural design process. What is important is that young engineers should know how to use computers to get a better understanding of structural behaviour, rather than treating them as a magic black box that will spit out the right answer at the press of a button. A high school introductory course is a good opportunity to do just that.

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[r13]

IDS,

Nobody is against computer use in engineering practice, it is a tool that function in many ways to helping us to achieve goals, and yes, occasional to look at the pretty stress diagrams or contour map to verify our models and assumptions. The verification require knowledges and experiences, otherwise we are only a bunch of key-punchers.

 

[Ron]

@IDS...Doug, I agree that computer analysis techniques are important, but they also need to know the calculation basics. Most states require that engineers validate their software with hand calcs.

 

[CANPRO]

Trying to teach structural engineering in high school seems like you're putting the cart far before the horse. You need to have a good foundation in physics, chemistry, math, etc... before getting right into something so specific as structural engineering.

I gave a presentation to junior high class a while back on the basics of bridges. I focused on building materials. It was something that they can see and relate to - it was fairly well-received and generated questions that led to somewhat technical discussion like what galvanized steel is and what the process is like.

Discussing the different materials allowed me to touch on topics like composite action between concrete bridge decks and the steel beams. To demonstrate this I had two physical samples - one stack of paper bound by just clips at the edges and a similar stack of paper where each sheet was glued to the next (took a while). I passed the two samples around for the class to bend so they could see and feel the difference shear flow makes.

I prepared another series of 3 physical models for demonstration - a stack of loose wood blocks to represent unreinforced concrete, same blocks but with a threaded rod through to represent reinforced concrete, and the same threaded rod assembly but I really tightened hard on the nuts to show the effect of pres-tress/post-tension.

 

[IDS]

retired13 and ron - I didn't say or imply that they shouldn't be taught the basics, quite the opposite.

What I am saying is that students should be shown how computer analysis can lead to a better understanding of the basics, which is very much more than "occasional to look at the pretty stress diagrams or contour map".

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[r13]

Before the introducing of calculator, I used to do simple math in my head, but I doubt I still can do multiplication or division with more that two digits, with or without decimal point. But I agree that the senior/graduate student with moderate software exposure will have an advantage early on in his career.

 

[Phil1934]

Divide them into groups. Give each group a fixed amount of play money. Present jobs to bid. Each bid would cost 5% of their bid. Each job would present a profit or loss based on your secret engineer estimate.

 

[dhengr]

Rrumer:
Why not run this program in conjunction with their regular General Science course, or with the Physics and Chemistry courses. Then bring in practicing engineers in all the various fields to actually teach (or help with) their own fields of practice. Do experiments, demonstrations, pictures, site visits of real world examples of that particular Science, Physics, or Chemistry principle. At that age, what they really need is real world examples of how the Science they are learning exists in their life, in the news and in the world around them. They probably don’t need to know, in much depth, how load, shear, bending moment, slope and defection follow from each other, in the design of a simple beam. You too quickly get into details which leave the second year college engineering student scratching their head. Let your depth of coverage flow from their questions after your basic presentation, experiments/demonstrations, slide show, etc. on a particular subject. And, for goodness sakes, leave computers and software out of it until there is some real understand of some of the basic concepts and principles. We already have way too many pretend engineers who can’t do the most basic structural design problems without their computer. At the same time that they are an important tool of our profession today.

 

[STrctPono]

I'm with IDS on this one. High school kids these days would expect computer analysis/modelling to be part of Engineering. No better way to kill their interest in Engineering than to simplify everything down to some simple 2D beam models on paper. At least sell them the pipe dream now so that we can bait and hook them.... Let the feelings of boredom, self loathing, and career discontent come later when they're in their mid 20's and $200,000 in school debt!

 

[GregLocock]

I suggest reading both of JE Gordon's masterpieces and pulling the good stuff out of them.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[FloydLloyd]

Overview of structural systems: Tragsysteme, Heino Engel

Antoni Gaudi, funicular modeling to determine shape of masonry structures acting in compression. Geometric Shape, Structure and Material in Antoni Gaudí’s Work

Kenneth Snelson, Tensegrity, Art and Ideas

 

[271828]

The original post describes a survey level summary of a big chunk of a BS program. A college student studies those topics over four or more years. The HS students can't comprehend that timeframe, so they'll feel like it's hopeless to learn all of that. They would be utterly overwhelmed. Especially forget all of the mechanics. Bending moment? They barely know what a force is at this point. It's not super easy to explain to college students what a bending moment is. Young's modulus? Before explaining that, you'll have to explain what linearly-elastic and a whole bunch of other terms mean. All of those topics are not a little beyond them at this point.

Keep it extremely nontechnical.

Show lots of pictures and sketches of structural systems. Show them a wood floor with joists, joist seats, plywood subfloor, and underlayment. Talk about how the plywood spans to the joist and the joists span to the walls or girders. Talk about a few easily understandable modes of failure such as the joist bending. Show them a joist seat and a joist bearing on a wall. Point out the studs right under the joist bearing. No numbers or equations. Similar with concrete and steel systems. Just explain how these work qualitatively. Take them to see a construction project near the end of the course and point out these various elements.

 

[gtaw]

Simple demonstrations that catches their attention and gets them interested in the subject. You don't need to get into the math if it is any deeper than a simple linear equation or simple algebra.

I used the demonstration already mentioned. I took a scrap piece of plywood and cut into 3 x 4-inch pieces. Each had a 9/16-inch hole in the center and another 1-inch hole from the bottom edge. I ran a ½-inch threaded rod through the center hole, supported the “beam” on two chairs. The beam sagged. I rearranged the threaded rod through the bottom hole, but placed it so the rod was at the to of the beam. It nearly sagged to the floor. Then I rolled the beam over so the rod was at the bottom. I could stand on the beam and it barely sagged at all. The discussion: the placement of reinforcing steel. The audience: first year Ironworker apprentices.

One apprentice said he didn’t understand tension and compression. “You’re always talking about tension and compression. What are you talking about?’
The beam that was still positioned between the chairs with the threaded rod placed near the bottom edge in front of the class. I told him it was easier to show what compression is than it is to talk about it. I lifted the center of the beam so that the plywood blocks opened and separated. I said, “Put your finger between any two wooden blocks.” And he did exactly as he was told. I slowly lowered my hand and as the blocks squeezed his finger and he was commencing to howl, I said, “Now that’s compression.” That got a laugh from everyone. Fifteen years later I saw him at a meeting and he leaned over and said, “I still remember what compression is!”

Simple demonstrations to spark their interest and then a simple explanation of what they saw and why it happened.

I built a small truss out of 1/8-inch welding rod. It was 36-inches long and about 2-inches deep. All the connections were soldered. I supported it at the ends and hung one-gallon jugs of window washer fluid from it. There were as many jugs hanging as I could tie on. I asked the crowd what would happen if I cut just one web member? The response heard the most was the truss would sag. What if I cut two web members? “It will sag more.”

As I cut one web member, the truss crashed to the floor with jugs of window washing fluid rolling this way and that. The audience consisted of building officials and engineers. The demonstration was held at the University of Massachusetts, Amherst. No discussions about the math involved or the theory, just the demonstration and the statement, “And that’s why you don’t let the plumbers and Sheetmetal workers remove the web members of open web joists!”

Simple demonstrations to spark their interest. For young students, a simple projects to let them try their own ideas. A bridge made from popsicle sticks and loaded to destruction is one they love.

I did a lecture for a local college on the subject of welding and careers in welding. It was a presentation over the course of two days. We talked about careers in industry related to welding. During the presentation we designed a simple welded connection and we had a contest. The contest was to fabricate the connection and to predict the load required to break the connection. The winner got a check for fifty dollars. The weld sustained a much higher load than any of them predicted. The connection was loaded to failure in a hydraulic press. When it broke, you could hear the bang throughout the building. The kids like the demonstration so much they welded up another one just to see if it broke the same way. The instructor said the kids were still talking about the demonstration a week later.

Keep it simple. Not all the students will be college bound, some will go to work in the trades, but regardless of their career path, they will remember the demonstrations and a few will decide this engineering thing could be fun.


Best regards - Al

 

[Ron247]

I do not know how many class hours would be devoted to this, but the list I saw in your posting is a lot to digest. My thoughts are with some others in keep the math and computers to a minimum. If all the kids can walk out with a basic understanding of how things work, that will benefit all of them. The math of column buckling at their stage is less important than why something buckles.

Here is a picture of a Staedtler eraser I have use many times to quickly illustrate a "feeling" for how things work.

Here are some examples of things that are helpful but not intense:
-Once you explain column loads for example, take the A, L, P and E that are used for how much the column compresses and have the class figure out what goes in the numerator versus the denominator. Instill the feeling more than the math.
-Not just explain Action-Reaction, have them predict simple things will fail or work depending on what you do to them. Kind of like stand on a desk or stand on a chocolate pie but not that simple.
-Load paths is almost essential to give them a start at. I run into recent engineering grads with issues related to load paths.
-Load path with Action-Reaction and you see why many engineers watch those failure blooper videos and foresee what is about to happen with the guy bicycling off the roof into a trash can. Watching those videos and then going through the science of why it failed would in fact be good. The really good Xtreme sports people have figured it out because even they cannot defy physics.
-Problem Solving and Goal Achievement are also talents that are useful to almost everyone.

To me, the class is for everyone to get something, not just those going into science. Your undertaking is admirable but difficult.

 

[fel3]

rrumer...

Lots of good suggestions above. I think top high school students can handle some of what you intend to cover, but probably only if they have had or are currently taking AP Calculus and AP Physics. For presenting these subjects to a more general high school audience, I suggest the approach taken by Stephen Ressler in his "Understanding the World's Greatest Structures: Science and Innovation from Antiquity to Modernity," (

https://www.thegreatcourses.com/cou...-innovation-from-antiquity-to-modernity.html)

Ressler is Professor Emeritus from the U.S. Military Academy at West Point and also the author of the West Point Bridge Designer software. His personal website is here:

https://stephenjressler.com/.

Fred

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[Landon Bell]

Thank you for such a valuable information. I was looking for a long time detailed explanation. Really appreciate your reply!

 

[RWW0002]

These kits are fairly expensive for what you get, but I have never seen a better tool for visualizing the behavior of various structures and framing types. Fixed vs flexible supports, basic member types and member end releases.. moment frame, braced frame and truss behavior.. Watch some of the videos even if you do not purchase.

https://molamodel.com/pages/info