Thank You!

Thank you for following us this semester!

Links to Final Reports

Dylan Akers

Turner Bohlen

John Clapp

Charlie Clapp

Caleb Lehner

Dylan Monroe

Aaron Rocha

Scott MacDougall

Chris Tosti

Testing Music Video

The students had a wonderful time testing their bridges last week. Below is a four minute music video that highlights the week. Enjoy!

THE RESULTS ARE IN!

Over the last 5 weeks, everyone in the Structures and Material Science class has been trying to build the best possible bridge they could, and last week we were able to test what everyone in the class came up with. The results were very impressive. Many people predicted their 30g bridge to hold a weight in the few hundred gram range, however, some bridges held upwards of 15,000g... YES, 15,000g! Below are the final results for the entire class:

Strength to Weight Ratio
Stephanie Strouse	90
Christopher Bassett	103
Dylan Akers	121
Caleb Lehner	138
Jeremy Constable	144
Christopher Becker	182
Christopher Tosti	194
Charlie Clapp	243
Scott MacDougall	339
John Clapp	390
Aaron Rocha	413
Dylan Monroe	526
Turner Bohlen	740
Overall Load	grams
Dylan Akers	2185
Stephanie Strouse	2605
Jeremy Constable	3185
Christopher Bassett	3500
Caleb Lehner	3585
Christopher Becker	5085
Christopher Tosti	6785
John Clapp	8585
Scott MacDougall	14585
Aaron Rocha	14850
Charlie Clapp	15090
Dylan Monroe	15265
Turner Bohlen	24412

Before I tested my bridge, I was very pleased with my design and the way I built my bridge. I was confident that it would hold a good amount of weight and would not fail early. My design consisted of a large triangle shape for the main part of the bridge with many supports from top to bottom. My cross section is by far the most detailed part of my bridge, however, when I tested I was surprised to see that this part broke first. If I had a chance to go back and rebuild, I would definitely change my cross section and make it more connected to the rest of the bridge so weight would be transferred more evenly.

 

Below are some pictures of my bridge before testing:

 

Front View

Cross Section

-Chris Bassett

Testing!

Testing is underway this week. We will be posting pictures, videos and results shortly. Check back soon!

End of Construction: Bridges Completed

My fellow classmate Dylan Monroe has a very strong and technically sound bridge. He uses two large triangles on the sides of the bridge along with a truss design to provide great strength. His finishing touches on his bridge were adding the horizontal connecting pieces on the top/outside of his bridge and also extending the width of his bridge to meet the width requirement of 6 inches. I believe that his bridge will be very strong due to the use of triangles and the clever substructure design.

My bridge is one of two in the class that uses an arc design. While the arc gives me great strength, it certainly has not come without complications. Recently while building the substructure i realized that the supports made the bridge sit unevenly, which will most likely be a problem during testing. It took me a few days to build the substructure because I had trouble finding out what positioning would be the best and how exactly I would go about attaching it. Hopefully the uneven sitting will not affect my bridge severely becasue the rest of my bridge seems to be very strong.

Side View (Finished)

Top View (w/o substructure attached)

 

-Scott MacDougall

Google Sketch Up & A9CAD

Before beginning construction, the students in Structures & Material Science thought about the design they wanted to create and drew a set of plans. Just like any modern day engineer, the students didn't draw the plans by hand, but rather used common CAD (stands for: Computer Aided Design) software. Some of the students used a three dimensional  software called Google SketchUp, while other's used a common engineering design software called A9CAD (similar to AutoCAD). Below are the designs of three students.

Turner Bohlen (Google SketchUp)

 

John Clapp (A9CAD)

Charlie Clapp (A9CAD)

-Mrs. Miller

last bit of construction

My good friend Jeremy works and lives next to me in the classroom and dorm so I see him when he is working on his bridge. His bridge is slowly coming along since he just added the arcs to the base. Now he has begun adding trusses along the arc.Once he has finished that he will put supports from the base to the arc. I hope the bridge will be done in time for testing; if he stays focused he might be able to squeeze everything in. However, spending some time out of class to build would make sure that everything is glued and sturdy.

In the past few days of working on my bridge I found that it was too long and definitely too wide. So I spent one day just working on added support for the bridge so it could sit on the blocks. Now the bridge can be tested properly. Also I have finished both smaller arcs (seen in the first picture) and supported them with two diagonal beams from bottom to top on each side. To finish the bridge I have to put pieces over the top and make the support for the weight to hang from.

My bridge

Best Wishes,
Caleb Lehner

Last week

We are entering our last week of building, and everyone seems to have almost completed their bridge. For my bridge, I have the bottom frame completed and I have just finished attaching the arches. Constructing the arches has been a difficult task, and I had failed at a few attempts. Currently, I am working on adding cross braces to connect the two arches. Since I added many extra days in my original timeline for construction, even if I run into more problems I should be able to compensate. The picture below is the bottom frame connected to the arches with some of the cross braces. The picture on the right is similar to what my final design will look like.


Caleb has also been making great progress on his bridge. During the first week of building, Caleb was able to enlighten us with a new joint he had created, which can be seen in the picture below. The joint is most similar to the braced miter joint, and is very stable. The overall craftsmanship of Caleb’s building is impressive. He uses minimal glue, and creates near perfect joints. For the last two days, he has been working on finishing the top of his bridge and is nearly complete. The picture on the right shows his new joint, and the picture on the bottom is his bridge.

Bestest Bridge Ever

The platform = Coolest part of my bridge

Charlie's Bridge

This week has certainly been filled with excitement as the final aspects of th bridges are beginning to come together.  Unfortunately, classmate Charlie Clapp has struck upon some unforeseen difficulties.  For the past few weeks he has diligently been making many trusses with which he will glue together to create his final bridge design.  However, he may be regretting this building technique.  Over the last few days I have overheard many sounds of desperation and despair from his corner of the room as he works on gluing all of the small pieces together.  Despite the tedious work and unfortunate setbacks, he has made significant progress overall. 

Although the rules do not explicitly state that you cannot use all four sides of the chasm (which must be spanned) for support, Charlie has devised a plan that will works around the rules. In fact, he has created a design that will use all available surface to keep his bridge afloat.  If his bridge ultimately performs poorly I am sure that he will receive no grief from classmates.  However, if it turns out to to be a strong design I am sure that he will be criticized for his sneaky way of working.

Now, my bridge, despite the slow process of cutting notch joints and making up my design as I go along, is coming together quite nicely.  Most recently I have completely finished the two sidewalls and began to connect them together.  Yesterday I made the platform from which the load producing bucket will hang.  I'm not going to lie, it looks pretty dope.  I'm not sure how practical all of the woven beams are, but they look wicked cool so I decided to take the extra time to put them in.  Other than building that platform, I have not been able to do much else.  Earlier today I was able to actually connect the two sidewalls with the platform along with six other single beams dispersed throughout the structure to make sure that the walls are vertical and parallel to each other.  I doubt I will need to add any further support to my bridge, and I will probably spend the next few days make sure that it looks cool.  Even if my bridge does not ultimately perform well, I know that it has been made with a loving heart and precise scalpel work. 

Love,

John Clapp

Construction Week 4

This week in Structures and Material Sciences my classmate, Chris Tosti, has been working on the frame of his bridge. The triangle that makes up the interior of his bridge frame, as seen below, was originally going to be an arch. Chris thinks that this triangular shape will provide his bridge with more structural support. He is building four identical frame pieces and plans to finish these frames in the next couple of days. Today Chris built a bridge deck that the weight will sit on during testing. His next step is to attach the four frame pieces to the bridge deck. His construction schedule is on track and Chris plans to be finished with his bridge in the next couple of days.

I (Steph Strouse) have designed my bridge to extend down from the bridge deck as seen in the picture below. Although this is not a conventional bridge, I believe it will be able to hold a significant amount of weight. This week I am working to combine the sides, front and back of my balsa wood bridge. It has been difficult combining these pieces because the glue does not dry quickly. I found a solution to this problem by using masking tape to hold the joints together while the glue dries. Because my bridge is fairly large and needs as much support as possible, I plan on spending the remaining days of construction adding more structural support to the middle of my bridge.

-Steph

Strouse and Rocha

 

Steph Strouse has been cruising along with her balsa wood bridge this past week. Her structure has really been coming together. She finished all her sides and has been assembling them into a three dimensional design. Strouse’s bridge is quite unstable on the platform but once some weight is thrown on it will rest perfectly into place. Another small issue is the excess glue. She plans to sand off some to make it look nice and spiffy. These last remaining days she also plans to add some more central support.

I myself (Aaron Rocha) have made tremendous strides in and out of class with my bridge. I now have completed six substructure walls and plan to make two more. I began assembling them to the bottom of my bridge deck along with beginning a top structure for more support. A big issue I had to face came when I placed my bridge onto the platform. The bridge deck was an eighth of an inch too high above the metal docks. To overcome this obstacle I made two rectangle frames to fill the gap. It is a perfect fit because the beams have a width 1/8-inch. I will continue assembling my substructure walls and finish my design for the top frame.

Week 3 Begins

Week 3 has begun, and the Structures and Material Science Class has resumed our Balsa Wood Bridge building. All of us have made a tremendous amount of progress on our own individual bridges, and it's starting to show! My bridge has been designed to incorporate several different types of triangles within its trapezoidal frame. The past two days have been mainly focused on trouble shooting any small issues that may have accrued by this point in the building process (the most common of which was individual connection pieces being cut slightly too small, creating a weak connection between the two pieces of Balsa Wood. I finished today's work period by cutting and attaching a platform to the up most section of my bridge, on which will rest the block that is attached to the bucket we will use to test the bridge's strength.

Side View of Dylan's Bridge:

My classmate Chris Basset has also made a great deal of progress on his bridge, a large triangular structure shown below. He reports very little difficulties and seems to be flying to the finish! He has finished both of his triangular side frames, and has cut but not yet attached the support pieces that will connect the two frames together. He still needs to finish cutting and gluing his bottom supports for on of the sides, but anticipates to finish well in time before our deadline, but has taken extra time here and there to double check connections and make sure that his bridge is in tip top shape.

Side View of Bassett's Frame, with complete abutment supports:

Side view of Bassett's other frame, with abutment support incomplete:

- Dylan A

End of Week 2

The Structures and Material Science class has made significant progress in the first two weeks of building as bridges are finally coming together. I personally have been able to make a lot of progress. My bridge design is composed of 52 crossed braced trusses. In the first two weeks, I have surprisingly been able to complete all 52 crossed braced trusses. I believed that I would need more time to build all the trusses, but my strong effort has put me almost four days ahead of schedule. In the coming weeks, I will be able to spend more time carefully gluing all the trusses together to form my bridge. Overall, the first two weeks of bridge building have run very smoothly.

Crossed Braced Trusses:



While I have been lucky to have run into no problems, John Clapp has suffered from a few setbacks. In the first two weeks, John planned to construct the trapezoid shaped sidewalls. However, the odd angles of the supports within the trapezoid forced John to have to change his design. This was a very beneficial change for John as it allowed for both easier construction and overall a stronger design. In the days to follow John was faced with yet another setback. John found that cutting the notches into the beams was extremely time consuming due to the exact precision needed to cut the notch into the beam. This setback put John slightly more behind schedule, however, he gained more experience with every notch. At the end of the first two weeks, John was eventually able to complete both sidewalls for his bridge. Overall, John ran into several setbacks in the first two weeks, but he has been able to learn a lot during that time, which will allow him to be much more efficient in the weeks to come.

Sidewall:


-Charlie Clapp

End of week 2

Everyone’s bridges are beginning to come together now as we finish off the second week of building. I have finished one half of the truss system for my bridge, and Chris Becker has created a large section of his bridge as well. Both of us decided on a triangular shape but went about designing it in completely different ways. Mine consists of two truss systems connected with beams while his is a series of layers, each smaller than the last, connected by strong vertical supports.

Chris Becker's Bridge:

My truss system:

In the last two days I have finally managed to complete one of my trusses and begin the second. Once I have finished constructing these I will connect the two with the roadbed and beams I mentioned earlier. So far, I am very happy with how the bridge is turning out, although learning as you go requires some patience.

Chris has been doing very well as well. He just recently managed to construct the pyramid top to his bridge, something that should add considerable stiffness to the design but was difficult to build. In the close up below you can see how he managed to interweave two triangle to create the three-dimensional shape.

- Turner Bohlen

Week 2 of Construction

Over the past week and a half I have been constructing a balsa wood bridge with a triangular design. I was able to construct the four main triangles which make up the bridge with little to no problems, but this week I have encountered my first real mistake. I added supports to the bottom of each triangle, thinking they would fit perfectly in between the blocks which our bridge must rest on. After adding the extra supports I realized that i set them millimeters too wide and they did not fit in between the blocks as I planned. In order to correct this problem without spending a lot of extra time taking them off, cutting them, and re-attaching them, I am going to extend off of the support. This extension I’m adding should allow my abutment supports to work properly and at the same time give a place for the bridge to rest on.

My bridge supports not fitting in between the blocks:

Solution:

One of my fellow peers, Scott McDougall, is taking on the task of constructing a balsa wood bridge in a completly different way from me. Insteaf of making a bridge which is made up of only stright pieces of wood, he is incorperating arches into his design. Although this is a tough task, he has been able to follow through with it with ease and nearly no mistakes. He has already created the arches for his design by soaking pieces of balsa wood in warm water and then tacking them down into their desired shape. This method has worked well, and he reports to me that the arches are exactly how he would have like them.

Scott's arches being formed:

-Dylan M.

Week 1 of Construction

After the first three days of construction I have worked on forming my arches and creating the bottom of my bridge deck. I have successfully made three arches and am in the process of soaking one more. In order to form the balsa wood I had to soak it over night in hot water, and then I taped and tacked the wet pieces into my arch. While waiting for my arches to soak, I have started to cut many of the pieces I will need for rest of my construction.

Also my classmate Aaron has made great progress on his bridge as well. Although he is not done, he is very close to completing his very sturdy bridge deck. Aaron just needs to finish making the deck on which the weight will sit and then he will have middle bridge deck out of the way. Like myself, Aaron has also cut many of the pieces while waiting for his deck to dry.-Chris T

Stuctures & Material Science!

Welcome to our blog! We started this blog to document the construction of our balsa wood bridges. During the next eight weeks we plan to show you pictures and tell you a little bit about our progress as we build these great structures that we have designed ourselves. At the end of the semester we plan on testing these bridges to see how much load they can withstand. We hope you stop by periodically and check out our progress!