Plank Bridge
Play Plank Bridge free online. Join the dots with a limited number of beams to build a bridge strong enough for a delivery truck, then watch it bend under load.
How to Play Plank Bridge
A delivery truck needs to cross a canyon. The canyon is drawn on a blueprint with a grid of dots, and you build a bridge by joining neighbouring dots with beams. You only have so many beams for each gap, shown at the top.
The truck drives along the road level, the row of dots between the two cliffs, so it needs a beam between every pair of road dots. When the bridge is ready, send the truck. The beams stretch and squash under its weight, and any beam pushed too far snaps.
A flat road on its own sags and gives way. Add beams above or below the road so that they form triangles, because triangles hold their shape. Some gaps have a pier in the middle that you can build on.
If the truck reaches the far side, you score 150 points, plus 25 for every beam you did not use and a bonus for the level. Then the next gap appears. From gap 10 on there are too few beams for one long bridge, so you must build two short ones that meet on the pier. If the bridge collapses, you can try again, but three collapses end the run.
Controls
Touch
- Tap a dot, then tap a dot next to it to place a beam, or drag between them. Tap a beam to remove it.
Mouse
- Click or drag between two dots to place a beam. Click a beam to remove it.
Keyboard
- Arrow keys move the cursor, Space picks a dot, Enter sends the truck and Backspace undoes the last beam. P or Escape pauses, M mutes.
Tips and Tricks
- Build a row of triangles above the road, like a classic truss bridge. It is the strongest shape for the fewest beams.
- Make sure every triangle is joined to the cliff dots at both ends.
- Once a bridge works, try removing one beam at a time for bonus points, but keep a copy of the shape in your head.
- Long gaps need taller triangles. Use the higher rows of dots for them.
About the Game
Plank Bridge is a small engineering puzzle with real spring physics. Every beam is a spring that stretches and squashes, so a bridge that looks fine on paper can still sag, bend and snap when the truck rolls on.
It is drawn as a blue blueprint with white beams that turn red as they strain. Your best score is kept in this browser and can go on the Top 10 board.
Plank Bridge FAQ
Why did my flat bridge fall down?
A road with nothing above or below it bends too far under the truck. Add beams that form triangles to keep it stiff.
What do the colours on the beams mean?
Beams turn from white to red as they are stretched or squashed. A beam that goes too far snaps.
How many collapses do I get?
You can let the bridge collapse twice. The third collapse ends the run.
How do I score more for a bridge?
Each beam you leave unused adds 25 points when the truck gets across.
