go-gales

Final bridge post

Wed, 09 May 2012 20:08:09 -0400

Throughout the process of building our bridge, many steps were taken in order to ensure that our bridge would have en extremely high, maximum load capacity.We only used the bridge design from the digital bridge a little bit. We used a truss system on top of the bridge but other than that we started with a clean slate for the virtual bridge. At first, we had planned to make a truss bridge with an arch running underneath it to better support it, but the designed was changed so that the bridge could hold more weight. Our new design was based off of that of a simple truss design with a number of trusses placed across the top of the bridge, and a deck layered with six, long pieces of balsa wood. At the end of each pair of trusses were joints that had been cut into square shapes to improve the bridge’s stability, as well as thin pieces of balsa wood that ran the length of the bridge on the points where the trusses touched the bridge, and along the top in between them. In the middle of the deck was a space where short pieces of balsa wood were placed in a diagonal pattern to increase the load capacity.

Before we began cutting any balsa wood, both designs had been drawn and scaled by Kyle Bonci on graphing paper, to make sure that our bridge would fit into the desired space. We began to measure and cut our trusses on the second and following days of class, so that we would be able to begin gluing our bridge together as soon as possible. After several class periods spent on gluing the bridge pieces together, during Easter Break, and towards the end of the project, Bryan Fay had brought the bridge home to his house to finish the bridge. On the testing day for our bridge, ours had gone last after watching many bridges break apart from the weight of the bricks. When we began to load the bucket attached to our bridge with bricks, we began to notice that our bridge wasn’t budging, and after using all the available bricks, our bridge had survived. The main reason for our bridge being able to handle the large amount of weight from the bricks, which was 417 newtons or around 95 pounds of force, was because of the large trusses on our bridge that diverted the force of the bricks and gravity away from the main area of pressure on the bridge, which had been where the bucket was hanging from. Another ideal part of our design was the thickness of our bridge deck and its layering, which greatly reduced the pressure the bucket of bricks had on it. Even though almost 100 pounds of force was placed upon it, our bridge “Girthy,” was able to survive and remain intact, one of only three bridges left in the competition

This is the middle of our bridge deck and we chose this pattern...

Wed, 09 May 2012 18:43:42 -0400

This is the middle of our bridge deck and we chose this pattern because we thought it would maximize the strength

This is our final product

Wed, 09 May 2012 18:41:40 -0400

This is our final product

Blog 10

Wed, 09 May 2012 18:39:25 -0400

Our bridge didn’t break after the entire load test so we will have to wait until the next lab period to see how much it can actually hold. Our bridge deck was 7/8 of an inch thick just about the limit and the weight of the bridge was approx. 117 grams which again was just on the limit. I think the reason our bridge was able to hold so much was because we maxamized the strength in every spot we could think of. We doubled up each part of the truss and stacked the bridge deck to limit which i feel was the reason our bridge held the most.

Bridge didn’t break podcast # 5

Wed, 02 May 2012 11:51:21 -0400

Bridge didn’t break podcast # 5

Blog 8

Mon, 30 Apr 2012 18:41:59 -0400

For the load test we will lay our bridge on top of the system . I hope that we will have enough room on the sides for the load test. I think that our bridge will do well and I think it will a significant weight compared to its own.

Blog 7

Mon, 30 Apr 2012 18:35:36 -0400

Today we have just about finished the bridge. The truss system was completed before today but the re-inforced bridge deck has been completed. Now we also have re inforced the lateral stability of the top of the truss system.

Blog 6

Fri, 20 Apr 2012 10:51:47 -0400

Today we are back from break and we have finished the top of the truss system. Today we are stabilizing the top for lateral stability. We are putting siding on the top and bottom of bridge double sided. We also made sure the race car fits on the bridge. We are still not sure how we are going to build the bottom truss but it should be similar to the top

Podcast4

Fri, 20 Apr 2012 10:36:59 -0400

Podcast4

Podcast 3

Fri, 20 Apr 2012 10:25:07 -0400

Podcast 3

Blog post 6

Mon, 16 Apr 2012 18:34:00 -0400

During break we finished the top truss structure of our bridge. We used a warren truss system for the top of our bridge. We also have doubled up the road portion of our bridge for even more stability. Now we aren’t sure whether to build a bottom truss. We still will double up our upper truss and further stabilize it across but after that we should be done

Blog post 4

Mon, 02 Apr 2012 13:29:52 -0400

Today we have started building the top of the truss system wee are starting to see if we will have enough wood to build a top and bottom truss system. The glue is also a problem because we can’t use the gusses until we have built the top of the truss. It has to stay stable until then which means we have to be gentle. We are using notch joints in the deck to stabilize the truss and we are going to put a “fencing” on the outside of the truss to stabilize it even more.

Podcast number 2

Thu, 22 Mar 2012 14:27:31 -0400

Podcast number 2

Physics blog 3

Thu, 22 Mar 2012 14:09:11 -0400

Today we have decided to completely change our bridge design. We have decided to make a bridge with two truss systems one on top and one on bottom. In the end we decided that it would be to difficult and risky to do a curved piece of wood. We have drawn a model to scale and are ready to start cutting and building .

Physics blog post 2

Wed, 21 Mar 2012 12:28:11 -0400

It is the second day of building the bridge and iwantaprize is getting close to a final bridge design. We are thinking about having a strait piece of wood on top of a warren truss with an arch under the truss. The tricky part is connecting the bridge to the test system and we will try to measure it exactly to fit right in the tester. But we may leave a little room so we can wedge wood between the walls so it will fit. Opposed to making it to big and then it won’t fit and we will be disqualified .

First podcast

Wed, 21 Mar 2012 12:19:19 -0400

First podcast

Physics bridge day 1

Tue, 20 Mar 2012 11:15:15 -0400

Today we drafted Eddie and stared to begin our bridge concepts. We got all of our wood started thinking of ideas . We feel that we want to to put an arch but the difficultly increases as the strength increases. We will have to treat the wood so it will stay bent and measure it out perfectly. We have a basic design now and are beginning to scale out the crucial parts.

Break Post

Sun, 01 Jan 2012 16:14:06 -0500

Potential energy and Kinetic energy’s sum are equal to the total energy. Tis means when the roller coaster is at the top its KE equal zero and its PE equals the total energy. When the roller coaster is at the bottom of the slope it has zero PE and all of the energy is changed in to KE and it also equals the total energy

Monday Posting

Sun, 01 Jan 2012 15:58:09 -0500

lukeypotatoes:

Today we went over some homework problems and started learning about machines. A Machine is a device for increasing force. It also can change the direction of the force. Work input = work output. W=E=KE=PE. After those notes we took a quiz which i completely AC’ED. (y) Go Gaels

luke good job on the quiz. we also learned that no machine has 100 percent efficiency that is why we can use the formula AMA/IMA x 100 to find the efficiency.

Break post

Sun, 01 Jan 2012 15:52:00 -0500

Efficiency = Work output/ Work input. No machine has 100 percent efficiency. Efficiency also = AMA/ IMA. x 100

Work=change in energy=Change in KE =change in PE.