Bell Weekly Blog- Week 4

In week three, the group was given a challenge to make the cheapest, but still serviceable bridge my the end of class. We learned quite a few things about what makes the best design, the best materials, and the best diameter of the members; meaning we were able to get the members as close to their breaking point without breaking. In the coming week, the group will learn more aspects about bridges that will help us in the future have a better understanding about bridge designs. The one major accomplishment that our group had this week was building a decently cheap, yet serviceable bridge. Some issues that the team might run into could be arguing over different bridge designs.

I think that, for the most part, West Point Bridge Design is very realistic. Not only do you just connect members to pivot points, but you also change the material and thickness of the members. The program also allows you to reduce the cost as much as you can by maxing out the tension/compression values for each member for the cheapest cost.

Schetley Weekly Blog - Week 4

This week we worked on our bridge in West Point Bridge Designer, trying to prefect our bridge design to maximize strength while at the same time reducing cost. I, personally am getting more and more comfortable with the West Point software, so it is getting easier to use and really analyze what the data from the software is telling me. For the coming week, my group and I plan to learn even more about bridges, continue to prefect our design, and overall make progress with this project. I feel like we still can lower the cost by adjusting material type and size in the future, and hopefully we can without drastically altering the design of the bridge. As for West Point Bridge Designer itself, I feel like it is a good representation for the bridge design process with the many different features of the software, such as the ability to alter concrete type, anchor points, number of piers, and number of lanes, and those features are just the setup before the actual design of the bridge. Once in the actual design part, the ability to alter member size, placement, and material really gives a good look at bridge designing complexity. While I do think that it is a good software, I feel that it is a good basic software. The software to me is not as intricate and realistic as bridge design could be. When the animation plays, the bridge sags much, much more than a realistic bridge would (actual bridges sag fractions of an inch, if at all), and I feel like that takes a bit away from the realism of the system. I also feel like bridge design is more complex than place a connector at a point in space, connect a few members, repeat, then a bridge is made. But as I mentioned earlier, WPBD is a good basic, introductory software for bridge design.

Staquet Weekly Blog - Week 4

Last week, as a group, we worked on the computer with the West Point Bridge Design program to try and make our bridges from last week more cost effective.  We ended up designing a whole new bridge, keeping in mind the fact that with less weight and material comes a cheaper bridge.  As a team we were able to design a bridge that costed less than any of our previously designed bridges and I think this is due to the fact that we were able to put all of our thoughts together to accomplish the task.  In the coming week we plan to learn more about bridge design to see what combinations to work better than others so we can design a really good bridge for the K'Nex competition.  We will also learn from the questions being answers by the research librarian.  I believe that West Point Bridge Designer is a great demonstration of the bridge design phase in a real life situation.  There are all types of bridges to choose from and after that it is all up to the designer.  It gives you the ability to change a lot parameters right from the start including bridge span, anchor points, number of piers, road deck material, and even how many lanes wide it will be.  It gives you the opportunity to see what the relative cost of that type of bridge would be and can be very insightful as to what is safe and what is not.  While all of these aspects are great, the program does leave out a lot of crucial pieces to building an actual bridge like the ground type, dynamic side loads like wind, and even what type of environment the bridge will be standing in (corrosive, salt ridden air for example).  It also does not give you an estimate for the actual construction cost of building the designed bridge.  Although it is not the perfect program it is extremely useful for students in an entry level bridge design course, and it gave me the chance to learn a lot about truss bridges and their core design.  

Bell Weekly Blog- Week 3

Throughout this week, our group basically learned the basics of the West Point Bridge Design program. We learned how to created a serviceable bridge, while keeping the cost in mind by not adding meaningless members. This week, our group has accomplished one bridge design each that was able to be serviceable to the truck. In the upcoming week, our group will mess around with some different materials and sizes of the members. 

Questions:

1.  Which materials are strongest for tension and compression?

2.  Which bridge design is better; a bridge with trusses under the asphalt or a bridge with trusses above the asphalt?

3.  What is the longest bridge ever made?

Staquet Weekly Blog - Week 3

The three questions I have prepared for our research librarian, Mr. Jay Bhatt, are as follows.  Roughly how many bridges in the United States are currently considered to be structurally deficient?  How much money will It cost the U.S. to repair or replace these structurally deficient bridges?  What is the length of the largest pier to pier bridge span ever built in the world?
Last week in class we learned about truss bridge design and how it relates to the bridges we are designing.  As a group we were given some time to work on possible designs by using West Point Bridge Design.  This week we will learn about researching bridges, a lecture that will be lead by Mr. Bhatt, our research librarian.  After learning about research tactics, we plan to meet as a group and further our bridge design, and work on making it cost as little as possible.

Schetley Weekly Blog - Week 3

This week was mostly learning how to use the CAD software West Point Bridge Design. This is the software that will be used to design and test the bridge before it will be "field tested." It was very easy to learn and is a very user-friendly software. I, personally, haven't dabbled adjusting the materials, size, and other options like that. I want to first get comfortable with the program before I get advanced with lowering costs and changing materials. I'm unsure of what we will do in the coming week, since we seem to still be in the introductory phase of the class. This week we might learn more about the different materials and hollow versus solid members. I am looking forward to learning more about bridges in this class this week.

Also, the three questions I would ask Mr. Bhatt these three things when he visits:
1) What is the strongest shape in bridges?
2) What is the strongest material in bridges?
3) What is the most-cost effective material in bridges?

A1-BELL

For my bridge design, I felt that it would be appropriate to create an arch that stretched from one end to the other facing up. The advantage to this design is that a semi-circle is a very strong shape. When the asphalt  part of the bridge bows in, the arch in my bridge design compresses each piece equally. If it were any other shape, some pieces would have not compression or tension, while other take all of the compression and tension. As for everything else inside the arch, i felt the best way to create strength to the bridge was to simply create multiple triangular trusses along the length of the bridge. Finally, I have vertical members to support the weight of the arch. In terms of change in design, I never actually changed the physical layout of the design. I only changed the thickness and materials of certain members. Members that had high compression (arch of bridge) were changed from carbon steel to quenched and tempered steel, which is a better material for compression. Members with high compression also had thickness added to them. The cost of my bridge after all the corrections have been made came to a total of $364,160. Through research and analysis of my bridge design, I am confident that I could knock off at least $50,000, using different dimensions and materials. Throughout my bridge design, I learned that the top of the bridge needs the most focus because it has more compression than any other part of the bridge. The three following figures show the 2D model of the bridge, the table of the test results, and a 3D model of the bridge with the truck in the middle of the bridge.

 Figure 1: 2D Model

 Figure 2: Table of Test Results

Figure 3: 3D Model

A1 -STAQUET

The goal of this bridge design is to build a safe bridge that is as cost effective as possible.  I choose to design my bridge with all of the steel members being above the roadway deck in a relatively arch shaped pattern.  I then integrated interior cross members in the form of triangles to give the bridge added strength.  I decided to use this shape bridge because I personally believe that an arch is the strongest shape possible for this type of construction, and the addition of triangular internal truss members only makes the design stronger.  I did not have too many design changes during my time I spent creating the bridge up to this point, only slight arch angle changes.  In the future I plan on experimenting with the different available materials and changing between hollow and solid materials to get my bridge to cost as little as possible.  My bridge currently costs $298,000, and with future work and experimentation I plan to get the bridge to cost under $250,000.  During this design process I learned that bridges are extremely expensive, and involve a lot of time and effort outside of the actual construction process.  Below, Figure 1 shows a 2-D view of the bridge in the drawing board view, Figure 2 shows the simulated truck in the middle of the bridge, and Figure 3 shows the load test results of the bridge.  

Figure 1

Figure 2

Figure 3

A1-SCHETLEY

My initial bridge design is just a simple arch bridge design with triangular truss members I settled on this after realizing that other shapes weren't as strong as a combination of arches and triangles. The initial design is very simple, which is expected since I am relatively new to not only West Point Bridge Design but bridge design in general. Initially I tried to incorporate two equally sized arches across the bridge, but I could not get the bridge to support itself, even without the truck on it. I actually realized that in order for there to be multiple arches, there must be a center column in the water. Right now the bridge costs $334,495.95, but as I become more comfortable with the program, the strengths and weaknesses of certain materials, and what is the best shapes for bridges, I feel like the bridge can go below a cost of $300,000, possibly even $250,000. Below are pictures of the bridge's 2-D design, its 3-D design, and the test results of the bridge.

Figure 1: 2-D Design

Figure 2: 3-D Design

Figure 3: Test Results