That's an excellent and very practical question for urban environments! I've seen plenty of bins with dents and cracks from bike handlebars or pedals. For a trash bin that needs to handle occasional bumps from bicycles, the best material choice is a balance of durability, cost, and maintenance.
For most public settings, heavy-duty, rotationally molded polyethylene plastic is often the top contender. This isn't your average plastic. It's a thick, seamless material that's incredibly impact-resistant. When a bike hits it, it has some "give," meaning it can absorb the shock without cracking or denting permanently. It's also rust-proof, graffiti-resistant, and relatively lightweight for installation. Brands like Toter or Glasdon use this for their most durable models.
A very strong alternative is galvanized steel. A thick-gauge steel bin, especially one with a reinforced lower body, is a tank. It won't deform easily from a standard bicycle impact. The galvanization (a zinc coating) prevents rust. The main downside is that it can be more expensive, heavier, and if the coating is scratched deeply, it might eventually corrode. The finish can also show scratches more visibly than plastic.
I'd generally advise *against* standard thin stainless steel (it dents easily), concrete (too brittle on impact), or basic thin-walled plastic. Look for bins marketed as "vandal-resistant," "heavy-duty," or "high-impact" – they're built for this kind of use.
So, for the best all-around choice: go with a rotationally molded polyethylene bin. For maximum toughness where budget and weight aren't primary concerns, a thick galvanized steel bin is also superb. Either will laugh off a bicycle bump and keep your streets clean for years.