Here is the full list of all 21 Bridge Constructor Playground achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Achieved all badges for all bridges!
25 failed simulations in a row for the same bridge.
A vehicle flew at least 5 grid units into the air.
Cars can drive on all of Island 4's bridges.
Completed all levels with trucks.
Trucks can drive on all of Island 4's bSouths.
Built a bridge with at least 100 construction elements.
Achieved 90 badges!
Cars can drive on all of Island 2's bridges.
Trucks can drive on all of Island 3's bridges.
Built a truck bridge which withstands over 95% strain without anything breaking.
Achieved 55 badges!
Ran a level simulation although not one single element had been built.
Trucks can drive on all of Island 2's bridges.
Spent at least 100,000 for a bridge.
One vehicle reached the opposite side of the bridge safely, the other did not.
Trucks can drive on all of Island 1's bridges.
Bridge completed although at least 1 part broke.
Cars can drive on all of Island 1's bridges.
Achieved 25 badges!