The Toothpick Bridge-Design The design relies on the four catenary arches to transfer the weight of a load to the four feet on each side of the bridge. One very important concept that was apparently lost on my son's classmates is the ratio of the bridges weight unloaded to the load that the bridge could withstand before failure. Also pay attention to the gaps at the intersections. Connect with me on , , , , or. Stop loading it any further at this point. By printing out a grid against the curves we wanted to make, we drew it to scale and sketched the curves onto several pieces of printer paper taped together. In the end, the two bridge far surpassed our expectations.
A sort of obscure trigonometric function used in non-euclidean geometry. What do you see when you look at his structure? In your project, however, you will be making the trusses by joining toothpicks. Well, you have tiny sticks of wood, and white glue. In fact we even tried the marshmallow challenge with candy pumpkins in the fall. Once you have the design in mind, start building slowly. Instead have a diagram of how you want it to look beforehand.
Option 1: build the tallest tower you can with a set number of toothpicks and candy gumdrops. . Abutments support a bridge on either side and connect it to the ground. The process is pretty simple, but you must do it correctly!! What I loved was how they continued to try new designs to get the highest reach. The image depicts the sketch I made for the base of the bridge. I was very surprized at the outcome. I would love to know! The best way to create curved beams is to draw its shape on a construction paper and starting to glue sticks on top of the paper following the cure.
The first 'flap' of the struts between the arches were assembled while still flat. Think of each place where building blocks are glued together as 'rivets' in your bridge. Initially, we had used a smaller container but it turned out to be too small to contain the weights. Position each toothpick so that it gets maximum strength. Now, we were getting somewhere. For this, you can go through good books on bridges with illustrations.
Pavers have to weigh about 10 pounds each. You know what, once I looked at it again. Building a toothpick bridge in schools is often found in physics or math classes in junior or high school, where in addition to the process of building the bridge students sometimes also have to get involved into algebra calculations of determining tension and compression effects of in each structural piece of the bridge design. Plan the toothpick bridge as if it were a real-world construction project. She presently homeschools her two young children, teaches professional development courses through the Heritage Institute, and writes a middle level secular science curriculum called Science Logic. She has extensive experience in both formal and informal settings. Remember, drawing it is one thing, assembling it is another.
See how different this task can by visiting In searching for the best design, there are a few things to consider. Pins, waxed paper, and now paper clips are a great help to holding things in place while the glue dries. Even though elaborate school-grade toothpick bridges for example of fully arched design can weigh over a pound, smaller bridges in the range of 100 grams can carry the load of four or five fully solid bricks! Two days of drying is enough. For example, a long, unsupported span will buckle under weight. This makes the material less hazardous for children, lighter and more uniform.
Start to sketch out your design for the bridge. Build the main components of the bridge, such as the deck, towers and arch, separately to promote even drying. Organizers of most bridge-building contests rank these bridges, highly. Your bridge will bend before breaking. Testing the Bridge Add a few weights to judge the capacity of the bridge.
One side of your bridge is made. This might be a hard choice to make, luckily you can always head over to and check out more great science resources! The catenary is curve made by a hanging chain. You can make your two segments as big as you want it just depends how wide you want to make your bridge. Project guidelines and materials can be adjusted for a specific focus or modified to suit different age groups. What is important to learn is what makes a good design, and what are the 'weak points' in the design. I used this paper as reference of the different types of bridges I could build.
This is a critical tip for building toothpick bridges. Toothpick Bridge Plans Here are a few toothpick bridge plans in pictures. Toothpick bridge is a simple construction method that is used by many students and engineers from all around the world who want to learn more about the basic processes of bridge building, truss structures, structural strength, resilience, capacity, main forces that affect the bridge components tensile strength, twisting, torsion, load bearing testing and more , creativity and experimental bridge designs. After our fall building challenge, the boys were determined to try another activity for creating and engineering, and building structures of their own unique designs using candy gumdrops. Enlisted here are a few common designs of bridges. Use knowledge of bridges to predict weaknesses in the design. I would like to hear about the rules for various contests and how the grading and testing is done.
Use every bit of the weight if your goal is to win the competition. I decided to go with the Warren with verticals design but you should choose one that would be easiest for you or the one you think would hold up the best. At the time, I remembered my dad's explanation of a catenary and I decided to look into that curve as a building block of the design. Choose round or flat toothpicks based on your design. To find this, one must use finer methods of testing. My group eventually went the popular kids plan Of course! There is a balance between design and safety.