Bridge moving-cart load testOpen original
USC · Week 1
Balsa Bridge
A balsa-and-hot-glue bridge that held twelve bricks in a moving-cart test before its thin deck became the limiting component.
WhenSummer 2026
My roleTeam project lead
StatusBuilt and load-tested
The goal
Build a balsa bridge for a moving-cart load test.
My work
Led the team’s structural design, construction, and testing work.
Hardest problem
Transferring concentrated wheel loads through the thin deck.
Result so far
Supported twelve bricks before deck puncture; the main frame remained standing.
The project.
I led our team's bridge project. We built a four-foot-long, one-foot-wide structure from balsa wood and hot glue, using inverted trusses, vertical slats, and supporting legs. Testing revealed that the deck needed reinforcement even though the main frame remained standing.
The wider project
A USC team project using balsa wood and hot glue to build and load-test a bridge.
My contribution
I led the team through the bridge project and helped identify the local deck failure revealed by testing.
12 bricks
Supported during the moving-cart test before deck puncture.
Thin deck
The wheels punctured the deck between reinforcements while the frame remained standing.
Engineering decisions
How it came together.
Build a path for the load
The design combined a truss structure with a deck for the moving cart. The challenge was to make the bridge work as a complete structure: a strong frame still needs a deck that can transfer a concentrated wheel load into its supports.
The failure was in the deck
The bridge held twelve bricks during the moving-cart test. The wheels then punctured the thin deck between its reinforcements; the frame did not collapse. That distinction identifies where the next revision belongs: local deck support beneath the wheel path.
Development process
What changed along the way.
Design and construction
Combine the trusses and deck
Lead the team through the balsa-and-hot-glue build and prepare the bridge for testing.
Testing and reflection
Identify the local failure
Use the moving-cart test to distinguish deck puncture from failure of the main frame.
Project photographs
A look at the build.
Explore the hardware, design views, and development stages.
- The bridge structure documented by our team.
- Building the balsa structure.
- A bridge concept model from the team project record.
Demonstrations
See the project
in action.
Original recordings from the USC project documentation.
Play the recordings here, or open them in a separate tab.
Skills developed
Team leadershipStructural designBalsa fabricationLoad testingFailure analysis