Honestly, the short answer is: do not rely on standard anchor bolts driven directly into asphalt. Asphalt is softer than concrete, softens in heat, and tends to crumble around point loads. Wedge anchors and sleeve anchors can work great in concrete, but in plain asphalt they loosen quickly and pull out over time.
Here is what I actually recommend depending on how the bench is installed.
If there is a concrete pad or footing under the asphalt, cut or core through the asphalt and mount the bench to the concrete below. In that case, use 1/2-inch hot-dip galvanized wedge anchors, epoxy-set threaded rod, or cast-in-place J-bolts. Epoxy-set anchors are especially good because they do not create outward pressure that can crack older concrete.
If the bench is going directly on asphalt with no concrete underneath, use heavy-duty ground screws or helical anchors long enough to reach stable soil below the asphalt base. Pre-drill through the asphalt with a hammer drill and masonry bit to avoid cracking, then drive the ground screw through the hole into the soil. Choose hot-dip galvanized or stainless steel hardware so it does not rust out at ground level.
For a light bench or a temporary install, large-diameter asphalt anchors with aggressive threads can work, but I would treat them as temporary. Use a mounting plate or oversized fender washers to spread the load, and check the bolts seasonally because freeze-thaw cycles and hot asphalt will cause movement.
For most street furniture, my go-to is 1/2-inch x 4-1/2-inch or longer hot-dip galvanized wedge anchors set into a concrete footer below the asphalt. That gives a solid, tamper-resistant, long-term hold without relying on the asphalt itself.