Week 5 Blog Post

There are many differences between the West Point Bridge Designer program and the actual construction of KNex. The most obvious difference is the realism in the constructing of KNex. When building with KNex, a physical bridge is created compared to a computer-simulated bridge on WPBD. This KNex bridge can be tested using weights and other methods of real world testing. There is also a difference in that WPBD can indicate the exact area of the bridge that fails and perform hundreds of weight and tension calculations in seconds. This is not as easy when testing a KNex bridge.
There are also many similarities between the two products. Both methods of bridge design use beams and joints to produce a bridge to be tested. Stronger, more expensive pieces can be substituted with weaker, but less expensive pieces and vice-versa. Doing this can save money by placing inexpensive pieces in areas where it isn't as necessary to support such heavy loads. Both end results are tested to hold the maximum amount of weight at the lowest possible cost.
Last week in lab, we began to experiment with KNex and get an idea of how our bridge design will be translated to a physical structure. We tried out many different ideas from our WPBD models and were able to come up with what we think will be a good, strong, inexpensive design. I'm looking forward to getting to work on the final bridge design and to begin testing. This week in lab, we will begin putting together our bridge design with KNex, testing is optional. I think we will make great progress with the design but I doubt we will be ready to test by the end of lab. I'm excited and optimistic.

Week 4 Blog Post:

          While using the West Point Bridge Design program it became very clear that there were clearly some pros to the system as well as some cons. To start off on the positive side the WPBD program clearly helped as a guiding tool for those who have never used the program or ever worked with bridges before. Also, the program gave measurements of the stresses that would occur when weight was added. Some others may think that the exaggeration of the sagging of the bridge in the program would be a con to it but there is a way to turn off the exaggeration when in the animation screen. Because of this I do not consider it to be a pro or a con. However, there was a specific con that stood out right away to me as well as a lot of others. The WPBD does not take into consideration any external forces the bridge may encounter. Some external forces that may act on the bridges may include but are not limited to rain, snow, and wind. Also there was only one vehicle crossing the bridge at a time instead of a bunch of vehicles of varying shapes and sizes. Finally, the bridge in the program is not able to take into account the changes that occur of a long span of time due to wear and tear. Overall I did find the WPBD program to be a helpful tool, but only up to a certain extent.
          While in class last week we looked at some of the bridges that people designed for that week. The lowest costing bridge was around $250,000 which was far less than the bridge that I submitted which was around $400,000. During class each group was asked to create another bridge to be the cheapest design which our group got the cost down to $250,000, but even this is probably still not close enough to the lowest costing bridge. While still very intrigued about how to design the lowest costing yet still effective bridge in the WPBD program I kept at it and was able the create a bridge that cost just under $230,000. Unfortunately I cannot submit this bridge to get the extra credit point, but that does not matter to me as much. Now I look forward to the week ahead to the transition from the WPBD program to using Knex to build a bridge. When doing this the group as a whole will have to meet more often than the previous weeks to create the best bridge possible.
-Robert LaChance

Week 4 Blog Post

            Westpoint Bridge Design has many positives and negatives.  I think the overall concept of the program does a lot to teach you about bridges.  It teaches you about what geometric shapes work best and what does not work.  One of my favorite parts of the program is that it shows you the cost of the bridge you have built.  I think this is really cool because you learn not to put extra materials into your bridge.  What Westpoint Bridge Design does really well is calculate forces that act on the bridge.  On the right hand side of the screen the program gives you calculated forces.  Unfortunately I feel like while the program teaches you a lot it is not very realistic.  In real life a bridge would not bend as much as this program portrays.  The program does not account for out side forces excluding the truck that crosses.  Other forces that should be accounted for are weather, wear and tare over time, and other vehicles that might cross.  Just because a bridge passes a weight test does not make it safe.

            Last week we saw the bridge that had the lowest cost.  This cost was around 220,00 dollars.  The bridge that I submitted cost around 280,000 dollars.  The class discussed what the definition of the perfect bridge was.  The definition we came up with was the cheapest bridge that can withstand the most amount of weight.  After our class discussion we broke up into our smaller groups to try and make the cheapest bridge.  Our group got our bridge down to about 250,000 dollars but this was still not as cheap as the cheapest in the class.  During the following week our group has continued to get our price down but not significantly.  Once we start working with Knex our group plans on meeting more frequently to work on the bridge design.  

-John Watson

Week 4 Blog Post

After using West Point Bridge Designer for a few weeks, I have noticed a few flaws but also noticed the realism in the program. The program does very well to mathematically predict the weight placed on certain parts of the bridge and determine whether or not that section is strong enough to support a given amount of weight. The program takes accurate calculations and does well to display the areas of the bridge that were not strong enough to support the truck. It can calculate weight and tension as well as displacement.
However, I do believe there are some aspects of the program that are not very realistic. For one, the program does not take into account stress put onto the bridge by weather such as wind rain and snow. Also, it does not account for the normal wear and tear every bridge undergoes over time. Despite these weaknesses, I think the program is about as realistic as possible for a bridge simulation program.
Last week, our group was able to come up with our least expensive bridge design. To do this, we put together many of our money-saving designs and combined them to form one, very inexpensive bridge. We used the thinnest possible beams and the cheapest material. When simulated on West Point Bridge Designer, the bridge sagged very much. This, of course, was not very realistic, but luckily the truck was able to make it to the other side of the river safely. I'm happy with this design, keeping in mind the goal of an inexpensive bridge. However, if the goal is to make a sturdy, safe bridge that can support larger amounts of weight, I would use more hefty materials and thicker beams.

Week 3 Post

On the weekend of 4/14 I went on a road trip with a friend and was able to get a good view of the Besty Ross Bridge that crosses the Delaware river. While on the trip I almost forgot about the assignment and that unfortunately lead to the not so great picture I took with my phone's camera. From what I could see the overall condition seemed to be fairly good. Nothing on the bridge seemed to be overly rusted or corroded. When my friend and I crossed the bridge it seemed to be built just about right for the traffic loads it takes on every day. While looking at every part that I could I did not find anything that seemed to pose a problem to the bridges structure. If I had more knowldge of each specific part of the bridge and what to look for I could probably find imperfections here and there but for now the Betsy Ross Bridge seems very well built.

- Robert LaChance

Week 3 Blog Post

Some questions that I would ask Mr. Bhatt are "What are the best materials to use when constructing a bridge?" I was wondering this while I was constructing my bridge on West Coast Bridge Designer. I would also ask "What are the advantages and disadvantages of each material?" I'm sure all materials have strengths and weaknesses but I was wondering what the advantages and disadvantages of each are. Finally, I would ask "How would you decide the best type of bridge to install over a given area?" I always wonder this when I look at bridges. It seems to me that suspension bridges are often used to span longer distances and truss bridges are used for shorter distances.

-Oliver Tillman

A1- LaChance

When approaching the task of designing the bridge I wanted to have a split between being structurally sound as well as cost effective. The West Point Bridge Designer gave the objective of a bridge that crossed over a river. I also wanted to try and mimic the sort of design that was used for the Betsy Ross Bridge. Like everything else that is designed my bridge design was tweaked a lot.

Bridge Design

Load Test Results

During the past week that was spent designing the bridge it started off as one of the preformed models. The Warren Deck Truss was the original design and it seemed to be an efficient bridge that kept its shape fairly well. Later in the week after fiddling around with materials to lower the overall cost of the bridge I decided to play around with the idea of putting the Warren Through Truss on top of the Warren Deck Truss. The cost went up at first but the stability of the entire structure seemed to improve.  I also changed the size of the supports as well as the materials that they were made of.

In the end the bridge had a total cost of $360,443.52 which in my opinion is not as bad as the $500,000.00 that the bridge started off as. I believe this can be decreased with further knowledge of exactly how the dispersion of force works on different types of bridges. The biggest thing that I personally have learned for designing this bridge is that very minute details can dictate whether a bridge stays together or breaks down.

Week 3

Last weekend I visited a bridge while going on a bike ride along the Schuylkill River.  The name of the bridge is the Strawberry Mansion bridge.  This bridge spans the Schuylkill River and is located in Fairmount park.  This bridge was built in 1896 which makes this bridge pretty old.  Originally the bridge only carried a trollies but is now open to motor vehicles.  The bridge is about 1242 feet long and 32.2 feet wide.  From 1991 to 1995 the bridge was closed down and restored.  When I visited this bridge it seemed old but I didn't notice any real dangers, just your every day rust.  But I would recommend that this bridge gets painted some time soon to prevent further rusting.

In last weeks lab we discussed important team work was and when our team got back together we discussed our personal responsibilities for the project.  One of the key things we went over as a class was how to compromise.  This is important because we will all have different ideas and we will only be able to use one idea.  After the class lecture finnish Robert and I work on the West Point Bridge Design while Oliver continued to work on the blog.  While playing around with the design for the first time we learned that a lot of thought needs to go into building a bridge.  One thing became clear while working on the bridge, every thing affects everything.  Our group is meeting today to discuss what our options are and what we will do moving on.  

-John Watson

A1-Watson

The final bridge design

 Load Test Results

When I was creating this bridge I wanted to see how cheap I could make it.  I first stated with a Warren deck truss, but I soon realized that the supports on the bottom would not be enough to support the bridges own weight.  The next thing I did was added supports also on the top of the bridge.  This was now enough to support the bridges own weight as well as the truck that went across.  After I got the base design down I started to play around with different sizes and beams.  The bridge is carbon steel through out.  The top supports are hollow tubes and most are about 55x55x2 with the exception to the beams in the middle.  Beams 14 and 18 are both solid bars because they take a lot of pressure and hollow tubes would not cut it for their specific job.  Beams 15 and 16 are hollow tube but are slightly bigger than the rest at 140x140x7.  On the bottom part of the bridge I played around with sizes a lot.  Every beam is a solid bar because they take more weight than the top of the bridge.  The sizes of the beams vary because I tried to make them as small as possible to make the bridge as cheap as possible. 

            The final cost of my bridge was $282,091.88.  This cost could be lower if I switched things around, like hollow tubes and solid bars, types of metals, and different designs.  I think that I reached my goal of making the bridge as cheap as possible.  This is technically a safe bridge but I would not feel confortable crossing it because it is on the edge of collapsing every time the truck crosses.  While making this bridge I learned that there are a ton of different ways to make a bridge and there are a ton of variables that go into making a bridge like material, size, and type of beam.  There is always a way to make a bridge better or more cost effective.

A1 - Tillman

The object of this bridge is to provide a sturdy, reliable pathway over the river. This bridge has the upper section of beams to provide additional support. There is also a strengthened section in the middle. This section provides extra rigidity to the structure when the load is in the middle of the bridge.

Over the course of designing the bridge, the upper supports were added. These were added to reduce sagging and provide the bridge with more sturdiness.

This bridge would cost exactly $594,995.40. To reduce cost, beams that don't undergo as much stress could be substituted with hollow pipes. In addition, certain, less-necessary sections of the upper supports could possibly be removed entirely.

While designing this bridge I learned that designing a bridge takes patience and careful testing. Also, I learned that cost is important but very difficult to manage. The best way to keep the bridge's cost low is to be smart with the materials that are used and place less reinforced material in areas where it isn't needed as much.

Week 2 blog post

     During week 1 of this Engineering 103 lab I got to meet the two other people who I will be working with for the rest of the term. While at class everyone basically did the same thing; received an introduction to the course from the professor James Mitchell, had a brief overview of truss bridges, watch a brief yet quite amusing video of a bridge simulator (the West Point Bridge Designer computer program), and created a blog where each detail of the activities done in lab and outside of lab will be posted.

     For this week’s assignment the group as a whole needs to figure out what problems do we see happening in the foreseeable future. After finding out that my group members and I all live in the same dorm most the communication and meeting to collaborate on projects problems have been virtually erased. The division of all the work at this point does not seem to pose as a problem, but this is a crucial part to have a good functioning group. At the best of my knowledge at this point in time the only problem that I can see happening is just having different ideas when approaching an assignment, which most likely be settled easily because my group seems to get along. As long as our group keeps up if not ahead of each week's assignment this project should go fairly smoothly.

-Robert LaChance

Week 2 Pre-Lab Post

Our first engineering class was spent outlining course assignments and requirements along with a brief introduction on bridges, specifically the truss bridge design. We explored a few real life examples of truss bridges and our professor gave a brief tour of the "West Point Bridge Designer" computer program. This program is used to design and test bridges by simulating a truck driving over the created bridge. We were informed that by the end of the class we would have created a bridge to be tested to withstand weight. The final minutes of class were spent creating blogs and adding our group members as users.

It is clear that in order to build an effective bridge and get a good grade in the class, all of our group members must work together and cooperate. I think my group members and I will perform very well over the course of this project because we are all working towards the same goal. Dividing up responsibilities evenly and consistently meeting weekly outside of class is a good way to keep everyone in the group, including myself, on top of things. The tasks each person is responsible for will depend on that person's strengths. As of now, I don’t foresee any major problems facing our group because we have just begun. I’m excited to start working.

-Oliver Tillman

Week 2 Blog Post

The first week of engineering lab we basically learned what was expected of us and what the course involves.  During the first part of class we went over types of bridges.  One type of bridge design that was brought up a lot was the truss bridge.  Our professor did a tour of a couple of different bridges on “Google Earth”.  The bridges that were shown were from all around the world.  Another key part of class was the introduction to “West Point Bridge Designer”.  This was software where you can create bridges of your liking.  This seems like it would be really helpful when coming up for a final bridge design.  During the last part of class we were in charge of creating our blog.

            There are three main tasks we will have to complete this term, which are building a bridge, keeping up with our blog, and then the final report.  When we met up and discussed about teamwork one thing stood out.  All work should be split up evenly to make it easier on everyone.  We will also need to work well as a team, this project depends on it.  Setting up meeting will also be a challenge since everyone has their own schedule so we will have to keep on track with that.  Our group does not have a lot of experience with bridges so this will be a learning experience for all of us, which is why teamwork will be so important.  I think we should discuss everything that comes to mind; no idea is stupid.  This seems like it will be a fun term and can’t wait to start working!

-John Watson