Week 4 - Yilei Jiang

    Last week, the major thing we did was building a bridge design via West Point Bridge Design, which is a program to design a virtual bridge. Because of this designed bridge, I knew the basic knowledge of  bridge building components, such as span, material, placement of the travel surface in relation to the structure, and form. The other thing I knew was the cost of a bridge design played an important role. Related to reality, the cost also always decides that a contract is signed or not. 
     
     There's a thing that only can happen in West Point Bridge Design, not in our real world. During the testing, the truck passed every time whatever the bridge I designed looks like. Sometimes, my bridge was down to the bottom of canyon. It's not a serviceable bridge in the real world. 
      
     Next week, we will get the K'Nex and I will put the knowledge I learnt from WPBD on K'Nex. We can use K'Nex as a model to build a low-cost and serviceable bridge. K'Nex is not like WPBD. It is a model made up of solid materials(members), which means it has its own tension and strength capacities. How to hold heavy objects with the K'Nex bridge is the goal during these weeks. 

week4-BaiXue

Last week in class we are try to make a bridge with the lowest cost. At first we are doing two side bridge, but it end up with a high cost. By effect with the bridge that showed in class, we end up with a bridge that is one side and the price of around 240,000. Next week, we may have a guest speech that is about the bridge. For the end of the next class, I would know better about bridge and how to build the bridge.

We are now using West Point Bridge Designer to designer bridge. When comes the point of when we building the real bridge to build, which we use K’NEX. K’NEX is not a good quality thing to build a bridge. By using K’NEX, we are not able to change the size of the part. There also limited length of the part. It limited the shape that could make. Fuser more the connect part of the K’NEX is very weak and easy to get apart. What the WPBD can do may not happen in the really world. The support point of the bridge is also something to think about. On the WPBD there is no problem with the support point. When we made the real bridge there would be a lot of question come out. The WPBD is more about an idea world. One the real bridge there would be a lot of thing that unexpected happed.               

Week 4- Kyle Hayes

This week we gathered our group’s designs and tried to find the best parts of the three and create an even better bridge. we did manage to cut a few thousand dollars in cost, down to around$240000. We wanted to make a bridge that was only either a top truss or a bottom truss which did work and was a bit cheaper that of a bridge with a top and bottom truss. In my personal opinion I prefer the top and bottom truss bridge, although more complicated I found it to be less challenging to make and might give more strength on the actual model. With a bit more experimenting I came to the conclusion to use only hollow bars because they are cheaper and always stronger, the reasoning was explain be a TA that it is because it has a higher moment of inertia and thus will hold more weight. Also that when the bridge is is arched the weight wwill be distributed better and thus arch trusses can suport more weight.

WPBD is a very useful tool to make bridge design and test tension and compression. However I do not like using it for a model for the K’NEX competition. The K’NEX will not be joined perfectly like on WPBD also the K’NEX are all solid made of the same material and can’t be thickened so the fact that these can be changed and the goal in WPBD is to make the cheapest bridge not cost to strength ratio. If the bridge in the model is made solid, out of the same material, and same thickness then this can be more useful but they way it is being used is not very accurate for this assignment.  Two other problems with WPBD are there are no other forces, such as wind or age and rust; WPBD is only for the ideal conditions. The second is that the load added is fix, the weight added is limited to the one truck, which tell if it held or fell and the tension each piece was at, if more weight could be added and to a fixed location it would actually provide a defined weight limit and the cost of the bridge which would give a ratio used in our competition. WPBD is a very nice tool to make designs and see if there geometrically stable but not great when some conditions are fixed and real life is not ideal.

Next week we will use the knowledge gained by the guest speaker and use that to help with the next bridge design. We will also try a final analysis using WPBD before we start building the K’NEX model based on all the information gathered.

         - Kyle Hayes

Week3 - Yilei Jiang

This week I experienced how to build a basic truss bridge via a software, WPBD.  I knew two cross sections and three material types. Tube will be much cheaper that Bar if we think about the budget. For CS, HSS, and QTS, my bridge design was more like to use HSS because the bridge passed test as soon as I changed CS to HSS. However, HHS is more expensive than CS. Thus, QTS is a proper choice. QTS is a material that can support more tension than CS but less than HSS. And the price of QTS is between that of CS and HSS. From cross section part, I used Tube because it much cheaper than Bar. However, Bar can hold double or more tension and compression than Tube. So I think that increasing the truss' size is a good idea.

Then the question was coming after. Is there any other way that make a useful bridge and reduce the cost?
As so far, I don't have enough knowledge to support I build a prefect bridge.

So my three question will be?
What is the strongest structure that a bridge has? one side or two side? or other?
Why the bridge always fail when I first designed it, which I just followed the model WPBD gave?
If I want to know different bridge designs, what kind of books should I looked for?

For next week, we will continue the West Point Bridge Design and figure out what are necessary components of a real bridge design.

A1 - Jiang

My goals of designing the bridge are from two sides. One is spreading the tension into top and bottom. Two is using diverse materials and changing the size of them to reduce the building cost. I think that if I use this way to build a bridge, it will be safe and low cost.

Bridge in 2D mode

The Truck in animation mode

The load test results

The original price of the bridge was double as current price due to the cross section I chose, which was Solid bar.   After I using Hollow Tube instead of the bars, the cost was suddenly cut a half, however, the truck didn't pass the test. The compression strength of the tubes was much lower than that of the bars. So I decided to change the size of the truss on the top and the material of all trusses. I compared the cost when I increased the size and changed a stronger material of one same member. The consultation came after testing. Changing a better material is more inexpensive than increasing the size of trusses. For instance, I used quenched & tempered steels instead of carbon steels from the truss on the top. The price increased by $20141. When I kept using carbon steels and I changing the size of the truss, the price was risen by $32204 to pass the test.


Current cost: $292,788.76
I think that I can drop the price by $50000~$60000 with further time.

I learned that where the main compression and tension distribute on a bridge when a truck passes through. I also learned how to analyze the data from the load test results to adjust my bridge accordingly. I found out that the bridge could be failed down without any weight, just itself.

Week 3 - Kyle Hayes

This week I experimented with the two cross section types, bar and tube. I found tube to be more cost effective. Also I tested the three types of metals, CS, HSS, and QTS. I found HSS to be the most cost effective, it was much cheaper than QTS and only slightly more than CS but much stronger. I also came to the conclusion that condensed bridges are less expensive and perform better to less tension on such long piece that would have to be thicken to hold that same weight, so short and thin is better thick and long. With WPBD it was easy to make changes, test, and find the data on how to adjust from there. One thing I learned is that an easy way to be cost effective it to make some few important areas just a bit stronger will allow you to reduce many other areas allowing the bridge to still hold but still reduce the cost. Last I did some research into how trusses designs work.

My research of truss bridges has shed light on to why they are made with triangles and what the more common styles that are used, many have more of an X crossing rather than a crossing that goes to the left or right like /|/| / or \|\|\ . Also I learned that while truss bridges are very effective over short to medium spans, arch bridges seem to be more efficient and hold more weight when compared to the truss, so trusses that have an arch shape or angled on top tend to be better. In my research I found that many trusses are top trusses rather than bottom trusses, the reason being that the weight gets distributed downward and out to the ends better that way. These mean that the middle where the load is farthest from the distribution point at the ends and at the ends are the areas that undergo the most force and undergo it for most of the time meaning that these areas must be more enforced than the rest of the bridge.

What were going to do this week is to compare our bridge data and try to combine the best aspects of each and make them work together as best as possible. This week will mostly be a lot of analysis and much more testing in WPBD to see what can still be improved before we move to models .

My three questions will be:

What are the pros and cons of a truss bridge to other short to medium length bridges?

What is the strongest load design for a truss, normal or arched? Truss on top, bottom, or both?

When bridges fail what is the most common reason why and what is the area that fails?

-          Kyle Hayes

week3-baixue

     This week we learn how to use the west point bridge design. It is easy software to work with. It basic gives us tools to design a real bridge. In WPDB we can design a bridge by changer different shape of the bridge. There also different kind of size and type of martial that can choose to use. WPDB also have a tool that alone you to test bridge. That is really useful. By testing the bridge I can easy know which part need to improve. I finish my first bridge on class. That is really interesting. Next week we will continue working on WPDB and bridge. We still need a lot of work on Design Bridge. By working with team member can help get a better bridge designs. There also possible we will get a guest speech this weeks talk about bridge. I am looking forward to hear that.

There is some question I have that could be answer by the guest.

How many type of bridge in the world, and what kind of bridge is been common use?

As we now are talking about cost of the bridge, which bridge was the cheapest one over all?

It there are rule of which kind of bridge is use what kind of material to build it, or which material  can be only use on one kind of bridge but not another? 

A1-Xue

     my design of the bridge is made it as simple as possible, in order to use less material to lower the cost. my bridge is simple just one line design with out any other support part. use different size and type of the material to find out the cheapest way to build this bridge.

this is my disign 

this is the picture of truck on middle of bridge

Dennis H. Mahan Memorial Bridge
Project ID: 00001A-
Designed By: BAI XUE

# Material Type Cross Section Size (mm) Length (m) Compression Force Compression Strength Compression Status Tension Force Tension Strength Tension Status

1 CS Solid Bar 140x140 3.61 1815.80 2900.89 OK 0.00 4655.00 OK

2 CS Solid Bar 140x140 3.61 0.00 2900.89 OK 1803.10 4655.00 OK

3 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 1007.23 4655.00 OK

4 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 2780.52 4655.00 OK

5 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 3111.05 4655.00 OK

6 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 3106.40 4655.00 OK

7 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 2749.48 4655.00 OK

8 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 987.90 4655.00 OK

9 CS Solid Bar 140x140 3.61 1780.96 2900.89 OK 0.00 4655.00 OK

10 CS Solid Bar 140x140 3.61 1508.19 2900.89 OK 0.00 4655.00 OK

11 CS Solid Bar 140x140 3.61 1473.35 2900.89 OK 0.00 4655.00 OK

12 CS Solid Bar 140x140 3.61 0.00 2900.89 OK 1768.26 4655.00 OK

13 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 4279.52 4655.00 OK

14 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 4250.54 4655.00 OK

15 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 4414.65 4655.00 OK

16 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 3845.15 4655.00 OK

17 CS Solid Bar 140x140 4.00 0.00 2633.62 OK 3831.18 4655.00 OK

18 CS Solid Bar 140x140 4.00 2007.40 2633.62 OK 0.00 4655.00 OK

19 CS Solid Bar 140x140 4.00 1968.75 2633.62 OK 0.00 4655.00 OK

20 CS Hollow Tube 140x140x7 3.61 0.00 664.80 OK 563.99 884.45 OK

21 CS Hollow Tube 140x140x7 3.61 0.00 664.80 OK 549.05 884.45 OK

22 HSS Hollow Tube 140x140x7 4.47 0.00 707.46 OK 1100.99 1220.54 OK

23 HSS Hollow Tube 140x140x7 4.47 0.00 707.46 OK 812.01 1220.54 OK

24 HSS Hollow Tube 140x140x7 4.47 0.00 707.46 OK 779.60 1220.54 OK

25 HSS Hollow Tube 140x140x7 4.47 0.00 707.46 OK 1068.58 1220.54 OK

26 HSS Solid Bar 140x140 4.47 282.89 2501.00 OK 165.30 6423.90 OK

27 HSS Solid Bar 140x140 4.47 269.00 2501.00 OK 238.16 6423.90 OK

28 HSS Solid Bar 140x140 4.47 828.63 2501.00 OK 0.00 6423.90 OK

29 HSS Solid Bar 140x140 4.47 796.22 2501.00 OK 0.00 6423.90 OK

30 HSS Solid Bar 160x160 4.00 3603.43 4610.54 OK 0.00 8390.40 OK

31 HSS Solid Bar 160x160 4.00 3556.88 4610.54 OK 0.00 8390.40 OK

32 HSS Solid Bar 160x160 4.00 4166.39 4610.54 OK 0.00 8390.40 OK

33 HSS Solid Bar 160x160 4.00 4474.95 4610.54 OK 0.00 8390.40 OK

34 HSS Solid Bar 160x160 4.00 4484.26 4610.54 OK 0.00 8390.40 OK

35 HSS Solid Bar 160x160 4.00 4194.32 4610.54 OK 0.00 8390.40 OK

36 CS Hollow Tube 140x140x7 4.47 262.13 586.91 OK 216.91 884.45 OK

37 CS Hollow Tube 140x140x7 4.47 229.72 586.91 OK 249.32 884.45 OK

38 CS Hollow Tube 140x140x7 4.47 543.47 586.91 OK 0.00 884.45 OK

39 CS Hollow Tube 140x140x7 4.47 0.00 586.91 OK 530.66 884.45 OK

40 CS Hollow Tube 140x140x7 4.47 0.00 586.91 OK 498.26 884.45 OK

41 CS Hollow Tube 140x140x7 4.47 511.06 586.91 OK 0.00 884.45 OK

42 HSS Solid Bar 150x150 4.12 3188.56 3616.45 OK 0.00 7374.38 OK

43 HSS Solid Bar 150x150 4.12 3120.27 3616.45 OK 0.00 7374.38 OK

   
     When my bridge is first build out. it is really big and have a lot of cross on that. there were three part the up lever the middle and the low lever. it cost a lot of material to build it. in that time i only use one type of the materials which is the carbon steel solid bar. then i find out that there is a lot of part of the material has not been fully use. some of the only been use one or two present. i start to changer the size of the bar made some part smaller than other part. after that my cost of the bridge is lower by 100,000. after that i look over my bridge and try to find the way to make it simple. i get ride of the up and lower part of the bridge and increase the size of the middle. that made my bridge get cheaper. it also the bridge you saw now.

     my cost of the bridge is $276,145.62.

     if i working on that i may drop my price my $50,000-$60,000. by find out a better shape or lower the cost of the materials.

     by design this bridge i get know about the force and strange on each part of the bridge. some part get more force that the others. i need to put different material on different part of the bridge in order to handle the work it done. i use to think every part of the bridge is the same. now i get the full knowledge of the difference. i also find out, the part that break down could be not the part car are drive on. one member could afferent all the other member on the bridge.

A1 – Hayes

My bridge was designed with two main goals, make it compact and spread the tension into two parts, top and bottom, I felt this would hold the weight and make the bridge light as can be.

Bridge in Drawing board mode

With Truck in view mode

#          Material Type  Cross Section   Size (mm)        Length (m)       Compression Force      Compression Strength            Compression Status     Tension Force  Tension Strength          Tension Status

1          HSS     Hollow Tube    200x200x10    4.00     1441.03           1946.41           OK       0.00     2490.90           OK

2          HSS     Hollow Tube    170x170x8      4.00     1213.09           1234.91           OK       0.00     1699.06           OK

3          HSS     Hollow Tube    100x100x5      4.00     213.27 273.05 OK       0.00     622.73 OK

4          HSS     Hollow Tube    130x130x6      4.00     437.99 587.81 OK       0.00     975.38 OK

5          HSS     Hollow Tube    80x80x4          4.00     57.94   114.70 OK       153.82 398.54 OK

6          HSS     Hollow Tube    110x110x5      4.00     261.91 346.95 OK       0.00     688.28 OK

7          HSS     Hollow Tube    80x80x4          4.00     50.05   114.70 OK       170.08 398.54 OK

8          HSS     Hollow Tube    130x130x6      4.00     437.66 587.81 OK       0.00     975.38 OK

9          HSS     Hollow Tube    110x110x5      4.00     219.77 346.95 OK       0.00     688.28 OK

10        HSS     Hollow Tube    170x170x8      4.00     1165.06           1234.91           OK       0.00     1699.06           OK

11        HSS     Hollow Tube    200x200x10    4.00     1412.05           1946.41           OK       0.00     2490.90           OK

12        HSS     Hollow Tube    200x200x10    4.00     1721.12           1946.41           OK       0.00     2490.90           OK

13        HSS     Hollow Tube    240x240x12    4.00     2225.39           2972.71           OK       0.00     3586.90           OK

14        HSS     Hollow Tube    240x240x12    4.00     2396.91           2972.71           OK       0.00     3586.90           OK

15        HSS     Hollow Tube    240x240x12    4.00     2439.16           2972.71           OK       0.00     3586.90           OK

16        HSS     Hollow Tube    240x240x12    4.00     2456.75           2972.71           OK       0.00     3586.90           OK

17        HSS     Hollow Tube    240x240x12    4.00     2382.71           2972.71           OK       0.00     3586.90           OK

18        HSS     Hollow Tube    240x240x12    4.00     2180.86           2972.71           OK       0.00     3586.90           OK

19        HSS     Hollow Tube    200x200x10    4.00     1658.65           1946.41           OK       0.00     2490.90           OK

20        HSS     Hollow Tube    170x170x8      2.83     1330.42           1409.88           OK       0.00     1699.06           OK

21        HSS     Hollow Tube    170x170x8      2.83     1288.17           1409.88           OK       0.00     1699.06           OK

22        HSS     Hollow Tube    190x190x9      2.83     0.00     1819.47           OK       2037.92           2135.62           OK

23        HSS     Hollow Tube    100x100x5      4.00     0.00     273.05 OK       576.13 622.73 OK

24        HSS     Hollow Tube    35x35x2          4.00     0.00     4.70     OK       71.25   86.53   OK

25        HSS     Hollow Tube    100x100x5      4.00     62.44   273.05 OK       84.42   622.73 OK

26        HSS     Hollow Tube    60x60x3          4.00     0.00     36.29   OK       199.77 224.18 OK

27        HSS     Hollow Tube    80x80x4          4.00     2.33     114.70 OK       266.11 398.54 OK

28        HSS     Hollow Tube    90x90x4          4.00     34.16   166.09 OK       262.97 450.98 OK

29        HSS     Hollow Tube    60x60x3          4.00     0.00     36.29   OK       217.75 224.18 OK

30        HSS     Hollow Tube    100x100x5      4.00     59.73   273.05 OK       95.92   622.73 OK

31        HSS     Hollow Tube    40x40x2          4.00     0.00     7.17     OK       82.63   99.64   OK

32        HSS     Hollow Tube    100x100x5      4.00     0.00     273.05 OK       559.33 622.73 OK

33        HSS     Hollow Tube    190x190x9      2.83     0.00     1819.47           OK       1996.94           2135.62           OK

34        HSS     Hollow Tube    200x200x10    2.83     1318.88           2143.16           OK       0.00     2490.90           OK

35        HSS     Hollow Tube    200x200x10    2.83     1379.71           2143.16           OK       0.00     2490.90           OK

36        HSS     Hollow Tube    60x60x3          4.00     0.00     36.29   OK       171.81 224.18 OK

37        HSS     Hollow Tube    60x60x3          4.00     0.00     36.29   OK       163.44 224.18 OK

38        HSS     Hollow Tube    80x80x4          2.83     0.00     206.83 OK       279.32 398.54 OK

39        HSS     Hollow Tube    100x100x5      2.83     397.96 401.36 OK       0.00     622.73 OK

40        HSS     Hollow Tube    90x90x4          2.83     0.00     266.95 OK       392.28 450.98 OK

41        HSS     Hollow Tube    80x80x4          2.83     0.00     206.83 OK       382.19 398.54 OK

42        HSS     Hollow Tube    90x90x4          2.83     0.00     266.95 OK       260.04 450.98 OK

43        HSS     Hollow Tube    80x80x4          2.83     131.58 206.83 OK       133.95 398.54 OK

44        HSS     Hollow Tube    80x80x4          2.83     140.37 206.83 OK       125.16 398.54 OK

45        HSS     Hollow Tube    80x80x4          2.83     108.21 206.83 OK       150.72 398.54 OK

46        HSS     Hollow Tube    80x80x4          2.83     157.14 206.83 OK       101.78 398.54 OK

47        HSS     Hollow Tube    90x90x4          2.83     0.00     266.95 OK       232.48 450.98 OK

48        HSS     Hollow Tube    80x80x4          2.83     0.00     206.83 OK       384.87 398.54 OK

49        HSS     Hollow Tube    90x90x4          2.83     0.00     266.95 OK       433.17 450.98 OK

50        HSS     Hollow Tube    110x110x5      2.83     438.88 475.64 OK       0.00     688.28 OK

51        HSS     Hollow Tube    80x80x4          2.83     0.00     206.83 OK       283.45 398.54 OK

52        HSS     Hollow Tube    140x140x7      2.83     0.00     950.00 OK       1103.61           1220.54           OK

53        HSS     Hollow Tube    100x100x5      2.83     59.14   401.36 OK       232.76 622.73 OK

54        HSS     Hollow Tube    120x120x6      2.83     560.34 650.14 OK       0.00     896.72 OK

55        HSS     Hollow Tube    90x90x4          2.83     215.51 266.95 OK       0.00     450.98 OK

56        HSS     Hollow Tube    75x75x3          2.83     0.00     137.10 OK       209.12 283.18 OK

57        HSS     Hollow Tube    120x120x6      2.83     608.03 650.14 OK       0.00     896.72 OK

58        HSS     Hollow Tube    120x120x6      2.83     546.39 650.14 OK       0.00     896.72 OK

59        HSS     Hollow Tube    90x90x4          2.83     248.66 266.95 OK       163.63 450.98 OK

60        HSS     Hollow Tube    90x90x4          2.83     170.12 266.95 OK       242.18 450.98 OK

61        HSS     Hollow Tube    120x120x6      2.83     542.53 650.14 OK       0.00     896.72 OK

62        HSS     Hollow Tube    120x120x6      2.83     625.84 650.14 OK       0.00     896.72 OK

63        HSS     Hollow Tube    75x75x3          2.83     20.38   137.10 OK       170.10 283.18 OK

64        HSS     Hollow Tube    80x80x4          2.83     176.46 206.83 OK       14.02   398.54 OK

65        HSS     Hollow Tube    120x120x6      2.83     538.54 650.14 OK       0.00     896.72 OK

66        HSS     Hollow Tube    100x100x5      2.83     102.26 401.36 OK       234.00 622.73 OK

67        HSS     Hollow Tube    140x140x7      2.83     0.00     950.00 OK       1057.52           1220.54           OK

68        HSS     Hollow Tube    120x120x6      2.83     575.47 650.14 OK       0.00     896.72 OK

69        HSS     Hollow Tube    120x120x6      2.83     592.00 650.14 OK       0.00     896.72 OK

70        HSS     Hollow Tube    100x100x5      5.00     146.01 179.21 OK       132.55 622.73 OK

71        HSS     Hollow Tube    100x100x5      5.00     139.89 179.21 OK       138.67 622.73 OK

72        HSS     Hollow Tube    120x120x6      5.00     239.76 368.26 OK       80.17   896.72 OK

73        HSS     Hollow Tube    90x90x4          2.00     0.00     337.72 OK       404.31 450.98 OK

74        HSS     Hollow Tube    220x220x11    4.12     0.00     2411.10           OK       2529.19           3013.99           OK

75        HSS     Hollow Tube    200x200x10    4.00     0.00     1946.41           OK       2367.23           2490.90           OK

76        HSS     Hollow Tube    200x200x10    4.00     0.00     1946.41           OK       2367.23           2490.90           OK

77        HSS     Hollow Tube    220x220x11    4.12     0.00     2411.10           OK       2516.28           3013.99           OK

78        HSS     Hollow Tube    90x90x4          2.00     0.00     337.72 OK       408.73 450.98 OK

79        HSS     Hollow Tube    120x120x6      5.00     229.38 368.26 OK       82.99   896.72 OK

80        HSS     Hollow Tube    130x130x6      3.00     665.55 716.45 OK       0.00     975.38 OK

81        HSS     Hollow Tube    30x30x2          3.00     0.00     5.11     OK       2.96     73.42   OK

82        HSS     Hollow Tube    130x130x6      3.00     675.96 716.45 OK       0.00     975.38 OK

83        HSS     Hollow Tube    110x110x5      4.47     0.00     296.32 OK       672.65 688.28 OK

84        HSS     Hollow Tube    110x110x5      2.00     497.04 556.90 OK       0.00     688.28 OK

85        HSS     Hollow Tube    180x180x9      4.00     0.00     1506.95           OK       1939.27           2017.63           OK

86        HSS     Hollow Tube    180x180x9      4.00     0.00     1506.95           OK       1935.83           2017.63           OK

87        HSS     Hollow Tube    110x110x5      2.00     497.70 556.90 OK       0.00     688.28 OK

88        HSS     Hollow Tube    110x110x5      4.47     0.00     296.32 OK       661.20 688.28 OK

89        HSS     Hollow Tube    200x200x10    8.25     0.00     1040.87           OK       1963.88           2490.90           OK

90        HSS     Hollow Tube    90x90x4          4.47     106.78 132.87 OK       95.29   450.98 OK

91        HSS     Hollow Tube    200x200x10    8.25     0.00     1040.87           OK       1955.00           2490.90           OK

92        HSS     Hollow Tube    90x90x4          4.47     105.89 132.87 OK       87.22   450.98 OK

The bridge change material and cross section type numerous times to see which was most cost effective. The original bridge was twice as tall; all the bars were condensed because after testing length strengths I came to the conclusion that shorter lengths were not only stronger but cheaper. The Truss on top had and extra layer but it was excess weight with little function.

Current cost: $245174.28
I feel that eventually I could drop the price by $30000-$50000

I learned that the bridges aren’t always perfect on each side and sometimes only one side fails. I learned how to interpret the data on the load test results and tweak my bridge design accordingly. I also learned what parts of the bridge go under to most tension and how the weight gets distributed.

                   - Kyle Hayes