Primarily, I certainly did learn something worthwhile in this course. Although I am not an Architectural or Civil Engineering major, most of the lessons learned relating to physics and member failure can be directly applied to my study of Mechanical Engineering. Many of these concepts I had not known before, and being able to practically apply what we learn in physics lecture was refreshing. The least beneficial aspect of this course however, was the implication of West Point Bridge Designer. Although I really had no personal quarrels with the software, if I had to pick the least beneficial portion of the course, that would be it. With this single negative aspect came a multitude of positive learning experiences. Like I previously stated, after learning and studying and taking physics exam after physics exam, it was enlightening and refreshing to actually be able to make a real world connection to the symbols and numbers we only see in practice problems. Lastly, if I had to make any suggestions I would advise that the grading on the blog posts ease up a bit. It was really surprising to me how harshly I was being grading on blog post questions that were usually uplicates, I would receive full credit on one and half credit on a similar post with the same amount of effort and information.
Week 9
Over the course of the past 8 weeks or so, I can honestly say that the bridge design process has taught me a great deal; relevant to civil engineering and otherwise. First, I learned that due to varying load conditions of the real world, not everything that makes sense on paper is servicable in a real life application. Materials tend to act with a mind of their own, loads vary, and the way every structure performs under these as well as a plethora of other variables can go completely against what pen and paper physics might have predicted. Second, I learned that computer aided design in the production of bridges specifically is an incredibly crucial time saver. Although West Point Bridge Designer may not necessarily be the holy grail of realistic bridge simulation, programs such as this take pages of handwritten and manually computed physics and organize it instantaneously into graphs and charts. These easily-read graphs will also pinpoint where your structure will fail, and exactly why. Although reliable, once again the only true test is real world experience. It is very difficult to make these decisions as Freshman students with no hands on bridge experience, but opening up our minds to the different aspect of every part used has helped us to grasp almost every possible situation leading to failure. Lastly, I learned from Professor Mitchell that although having the best looking and most structurally sound bridge might sound like the perfect plan, in real life cost matters. Sometimes corners are cut in the name of winning a contract, and as paradoxical as it sounds, there are "safe" ways to cut corners. Very rarely is there demand in the real world for a beautiful bridge with an unlimitted budget.
Week 8
After using this method of analysis, I must concur that this is the beginning of a very effective process of analyzing legitimate forces acting on real bridges. Although this should by no means be the last or only method of analysis, it certainly will provide a great starting point. After using this analysis however, engineers must consider which materials they use and how each specific type of material can handle the tension and compression exerted by passing cars. This brings into consideration dynamic load forces. Unable to be calculated easily by hand, the use of a more advanced program than the web-based Bridge Designer software would be necessary to pinpoint where possible failures could occur.
If I needed to further analyze our K'Nex bridge, I would like to do as the article provided did and analyze the pulling force exerted by each cord into their respective gusset plates. I found it very interesting that pulling force capacity almost directly related to the capacity of each gusset plate, and this leads me to worry about any unfilled plates on our bridge.
Week 7
In comparing the K'Nex portion of the project to the WPBD software, a crucial component of WPBD is missing; finite element analysis and numerical data. Amount of force in WPBD was calculated efficiently per member, and could be used to push the bridge to its absolute limit before it failed. This would be incredibly useful in the K'Nex portion of this project, because purely recording or watching the bridge fail is not enough to determine to load on each individual member. It would be very helpful to, at least, be able to tell which members absorb little to no force and could be deleted to save cost. Also, using FEA to determine the exact forces on each member could provide focus areas of support. Although the main concept of the bridge is to have the best cost to effectiveness ratio, frequently designs need significant reinforcement to do even the minimum. Certain designs have worked far better than others in our experience, and the ones that worked better did not always contain more pieces. Being able to access analytical data from the testing of the bridge would point us in the right direction regarding how effective our bridge exactly is, where the forces are acting the strongest and how we could lean out the design to fewer pieces.
Week 6
As compared to last week, my views of K'Nex versus the West Point Bridge Designer have not changed at all. K'Nex are a significantly better approximation of what building a real bridge out of steel than WPBD is, and gives a better hands on feel for tension and other loads. However, building with K'Nex is not exactly like building with massive steel beams. Building with steel requires a significant amount of confidence in your design, and as stated in my previous post there is no, "do overs". Working with steel must be absolutely correct the first time, with a costly penalty for needing to remove or redesign. Also, obviously building with steel is much more time consuming and frustrating. K'Nex building is an accurate representation, but does not include real life situations regarding stress and financial problems.
Week 5
Although my opinions of West Point Bridge Designer's ability to recreate real life bridge construction, I must say that having a hands on experience is crucial, especially with constraints such as the K'nex pieces. The geometry we designed over and over on WPBD was not even remotely close to possible when we started attempting to assemble it. Although limitting, the K'nex pieces have given us new perspective on how a significantly more simple design would work just as well, if not better, and be much cheaper. As far as differences go between working with K'nex and solid steel, there are many. The biggest difference I can forsee is the ease of a, "second chance," with K'nex pieces that you absolutely do not have when working on a real scale. Positioning a two-ton steel I-beam is a time consuming and expensive process; something that is not necessarily easy to re-do if someone is not satisfied. Also in terms of differences, both between WPBD, real construction and K'nex construction, there are discrepancies in the way in which the members will fail. With WPBD as well as some instances in real construction, the connecting points are not the first to fail, but rather the members themselves contort and buckle. With reasonable force applied to K'nex, I would highly doubt a K'nex piece would ever bend enough to snap or buckle, rather the connecting pieces would let the crossmembers pop out.
Week 4
During Week 2, the team finally had the chance to toy with the West Point Bridge Designer software in class, together. Each member came to class with their prior bridge design ready, and we attempted the mesh the three effectively to create one, incredibly effective bridge. After our first and second tries, it was evident that we were spending entirely too much money. Our first project came out to $400,000, the second $300,000, then finally down to $250,000. After that, we were able to effectively manipulate each individual member to reduce the cost by as much as possible. Although, inevitably, the bridge does flex a great deal, the truck used in the software can safely cross. Each member was not only manipulated in material (the largest component in pricing), but in size until the maximum forces possible prior to failure were exerted on each and every part. Post-manipulation, the grand total was brought down to a comfortable $221,xxx.
After using WPBD for a few weeks now, I can say that it is an effective software in that it does build on the basics of bridge design and load distribution. Although today WPBD might not be able to accurately help someone bring a bridge design to life, it does help to instruct up and coming engineers. The program is realistic, but limitted.
In the up and coming week, the team is exited to possibly start taking our design off the computer and physically constructing it.
Week 3
Last week in lecture, Professor Mitchell displayed to the class a PowerPoint regarding truss bridges, as well as documentation on modern bridge failures. Looking into these bridge failures, it is easy to see that there is little to no margin of error when designing something traveled over by an infinite number of cars and trucks. Also, we discussed the importance of teamwork and how to deal with internal issues. Over the past week, the group and I have worked cooperatively using WPBD, and discussed possible shapes for our final bridge design.
As for questions I'm preparing to ask Mr. Bhatt, I have come up with the following:
- What is the most popular building material for modern truss bridges?
- What is the most efficient building material in terms of load capacity vs. cost?
- What bridge holds the record for longest span?
Week 2
Well, being that this is essentially our first week on the project, no tangible work has been accomplished yet. During Professor Mitchell's presentation on bridges across the country and the WPBD software, Nilay, Anurag and I have developed a few possible designs for our bridge. We have concluded that an Arched design will certainly be able to withstand a sufficient amount of force, and distribute it evenly. In the coming week, we have agreed to meet up and started drawing either using CAD, WPBD, or by hand a few possible concepts for our design and try to finalize a shape we all agree on.
Not much can be said for major accomplishments this week, other than getting to know each other and setting up our blog efficiently. Although we have thought about possible designs, nothing has been settled on yet so this cannot yet be added to the, "accomplishments," category. The only possible issue we face, is that one of our members is a commuting student and may not be as readily available. However, this is quite a stretch because we have already dealt with the situation and it will no in no way whatsoever cause any difficulty.
Being that each member of our team is now at the minimum; friendly, will certainly help in our quest for efficient teamwork. Teamwork will be crucial because we do have conflicting schedules, and certainly will need to be able to rely on each other to get our assigned tasks together. We can combat any discrepancies in role by assigning duties early on in the process, rather than sloppily dealing with things as they come. Using somewhat of a Concurrent Engineering methodology, each step of the process will be dealt with immediately, rather than sequentially dealing with each area of design and testing.
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