Balsa Wood Bridge
STEM LT Learning Goals
LT Focus Skills & Concepts (FSCs)
- Understand the concept of Scale Modeling and how it applies to design versus building.
LT Design Process
LT FSC Learning Path
Balsa Wood Bridge Design/Build Challenge Statement
Design and construct a balsa wood bridge that holds the most amount of weight while using the least amount of wood possible. An bridge design engineer’s job is to not only design a safe bridge to carry required weights/loads, but also to make sure that it is cost-effective (least amount of materials used to achieve the desired load). To simulate this process, our challenge will be judged by calculating the strength-to-weight ratio calculation to develop a bridge that carries a high load relative to the bridge weight. Strength-to-weight ratio is determined by dividing the maximum load carried by the weight of bridge.
- End to end, the bridge must measure 14 inches long/across, spanning across a 12 inch opening.
- The MINIMUM WIDTH of the Bridge Deck must have an opening of 2.5". Your Balsa Bridge structure must not be wider than 4".
- The MINIMUM HEIGHT of the Bridge must have an opening of 2". Your Balsa Bridge structure must NOT be higher than 6".
- Your Bridge must support a wood block that is 12" Long, 2" wide, and 1" high. This block must be able to slide though the entire bridge deck opening.
- There must be a 1" x 1" opening at the midpoint of the Bridge Deck as well as in the roof and any framing to allow for the testing equipment.
Bridge Deck & Roof - Take a new 1/2" Grid Paper to design your bridge Deck and roof.