Week 4: WPBD

For the past couple of weeks, our group was assigned to brainstorm with an idea of a serviceable bridge that also satisfies a set of constraints. To test out our individual idea, our group was introduced to West Point Bridge Design software. This was great software that helped us understand gravity behind designing a bridge. The West Point Bridge Design software was a very helpful tool in terms of visualizing the structural behavior and mechanism involved in the designing process. One of the realistic features in the West Point Bridge designer is that it calculates the cost of the bridge as it gets built. The cost consists of four components such as materials cost, connection cost, product cost, and site cost. The software helps us discover the most economical methods to design a bridge. One of the methods is to use hollow tubes for compression members and solid bars for tension members.

Along with constructing a bridge, the software provides an exaggerated animation of the constructed bridge. After the animation the software would also provide a feedback on what worked well and which members in the bridge failed to satisfy the task. The West Point Bridge Designer was realistic and helpful in understanding the factors that impact a bridge design in an ideal world. To build a real bridge design there needs to be more factors that needs to be addressed such as the location of the bridge, snow, labor cost, wind, and other loads that will impact the bridge design. Another major priority of a serviceable should be to with stand certain natural disasters such as earthquakes, and floods. Overall, the software was a great foundation for understanding the basic concepts that is involved in constructing a serviceable bridge.

During the previous week in class, we compared and analyzed different bridges that designed by other groups. This was a great way to understand different techniques and mechanism that can be applied in enhancing our bridge design. We also learned a great lesson about not getting too fancy with the bridges cause the objective is to design a serviceable bridge with the minimum cost. After the class discussion, our group was able to combine all the individual bridge designs into a single a design with a cost range of 230,000 dollars. During the process we learned the advantages in shortening the size of the solid bars and replacing the solid bars with hollow tubes. For next week, we will be introduced to the KNEXs and perform truss analysis. 

Week 4: WPBD

West Point Bridge Design is very excellent and useful software for engineers to understand how professionals design real structures. It is a tool that helps visualize structural behavior and also opportunity to experience the design process.  It also holds the purpose to demonstrate how engineers use computers as a tool for efficiency in their line of work. However, significant numbers of changes have been made to the software rather than the completely real life experience because they wanted it to prevent the program from being too complex. It serves to mainly demonstrate the design process and disregard the technical details of structures. Real engineers need to take many other factors under consideration for bridge efficiency and cost, such as abutments, piers, deck, all connections, concrete, framing, secondary membrane, and labor. Also the efficiency of the bridge is not tested correctly because many of the different loads are not taken under consideration, such as vehicles, self-weight, wind, snow, earthquakes, longitudinal and lateral position, and human errors. Another important issue that is missing in West Point Bridge Design is the concept of aesthetics, which is the individuals view on how a design looks good. Overall, it is a very helpful tool, but does not accurately reflect on how civil engineers really design a bridge.  Many of the West Point designs survive in the software but cannot last in the real world because it doesn’t meet the real physical requirements and effectiveness required for the project.

 Last week in class we compared bridge designs submitted by students and tried to understand what technics are the best approach. We also took a look at the design with the least estimated cost and realized that a simple design is enough, it does not have to be complex. For rest of the class we worked in groups to create the least costing bridge that is effective enough to get the truck across. Together we tried many different technics, such as material type, size, solid or hollow, etc. for the first time in the course we actually worked as one and put our thought together. For this week, I anticipate that we will finish up with learning how to create a good bridge design so that we can move on to using KNEXs. The course schedule shows that we will learn and start using KNEXs pieces to build a real bridge.

Bridge Design Sachin Patel

The bridge that I have constructed costs around $322,122,00. Though this is not a very elegant and fancy bridge it is able to carry very heavy loads. The bottoms beams are 140*140 carbon steel rod solid bars, the inner of the bridge is 160*160*8 quenched and tempered steel hollow rods, with the middle being a combination of 140*140-170*170 carbon steel solid bars. The bridge I wanted to build was a a very strong bridge, so I had first constructed the bridge to be of all quenched and tempered steel, but that costs an upwards of 600K. I knew that was just to unrealistic, so i replaced all the outside beams with carbon steel sold bars that were of the same dimensions. but i kept most of the inside hollow quenched and tempered steel hollow rods, which gave me the most durability and cost effectiveness.

Questions:  Sachin Patel
1) In the lecture we discussed using filters in order to parse through large amounts of data, is there anyway we can filter through the different types of truss bridges?
2) In the lecture we discussed e-books, does the drexel online e-book database hold all hard copy books in e-book form?
3) If i wanted to quickly sort if a source is scholarly or not, what are the tell tale signs of doing so, in a quick and precise manner with only look at the documents details and not previewing it?

Research Questions

Question 1:Where would I be able to information regarding software such as Westpoint Bridge design that can provide a virtual understanding of the mechanisms behind constructing a bridge?

Question 2:Is it possible for the Drexel libraries to be able to transition to delivering the engineering books holdings beyond the paper copy to e-books audiobooks?

Question 3: How would I be able to get access to the actual blue prints of the bridges across seas?

A1-JACOB

Design Image

Truck in Bridge Middle Image

Load Test Results Image

My initial objective was to design a simple truss bridge that guarantees a safe passage for the standard 225kN truck. Therefore, my initial design was a simple and straight bridge, constructed with carbon steel bars with a size of 140mm. Next, I constructed an arc that expanded 36mm and connected the arc to the straight bridge with carbon steel beams crossing each other. The estimated cost of the bridge ranged over $450,000.00. Thus, my new objective was to lower the cost of the bridge while ensuring a safe passage for the truck. Therefore, I identified the redundant beams and removed them from the design. Then I lowered the cost even more by replacing the solid bars with hollow tubes for the interior design of the bridge and only outlining the design with solid bars. After several trial and errors, I identified the beams that didn’t require 140mm in size and replaced it with less thicker beams. After all this process, my new estimated cost of the bridge came out to be $234,466.08. I strongly doubt the cost of the bridge could be lowered with further time and knowledge. Even if it is possible, it will only be lowered by couple hundred dollars. This was a great way for me to experience few of the challenges I can expect to encounter in my prospective job. Through this entire process, I learned several designing techniques and understood the factors that impact the construction of a truss bridge.

A1 - Parth Patel

At first I concentrated to build a bridge that is successful and safe for the truck to pass. Than I started to remove parts, change beams from solid to hollow, and also the thickness of beams, in order to decrease the bridge cost. Originally the whole bridge was composed of solid carbon steel beams of thinkness of 140m, which was changed in to variouse cheaper parts. It went from a large and tall bridge with a peak on top to a simple and straight bridge. The estimated cost decreased from 586,000 dollars to a current cost of 351,588.53 dollars. One main thing I learned is that it is extremely difficult to make a perfect bridge that is completely steady. Therefore, I realized the design does not have to be fancy and complicated to make the bridge survive. In addition I learned to use different types of parts for certain areas of bridge, such as to use solid and strong beams on the outer edge of the structure. I also picked up on few techniques on how to decrease the cost for the bridge. For example, a solid beam can be replaced by two hollow beams to be just as efficient, but still be able to save a little over a thousand dollars.