Why support rails(Parallel) available in railway crossings?

Question

Why support rails(Parallel) available in railway crossings?

Answer 1

They are not support rails, thery are called rerailers.  They limit wheel splay on braking and help re-center the wheels on the rails at crossings and after braking.  They are often at or preceeding crossings because these are often frequent braking or slowing points for trains.

Answer 2

They are called flangeway rails, and their purpose is to provide a narrow path for the wheel flanges to follow in case of a derailment or rough running bogie while crossing a level crossing.  The flangeway reduces the likelihood of a car or cars departing the right of way in one of these critical locations.

You will also see them on bridges, loading ramps, and other locations where a car running loose would be especially problematic.

Answer 3

Here they are called guard rails.

as stated above in the off chance that a rail car is bouncing along with a wheel on the ground, this guardrail will funnel the dragging equipment back next to the rail, I dont actually see them near crossings here but they start in advance of tunnels, bridges, etc.

They arent intended to rerail a car, of even prevent a derailment. Just move it to a safer location, seems bizarre doesnt it?

Added to Derail, yeahhh, i been there done taht, derailed on crossings and icy areas of industries. 4 times in one particularly misearble day.

Answer 4

Just earlier today, I was taking a train at 10 mph through a little used siding. Traffic and snow plows pushed snow and ice down in to the flangeways in a small town's main street crossing. It didn't look too bad, but as I rolled over it, the leading wheels of the locomotive rode up on the ice, off the rails,  and the engine started going its own direction. I was able to stop (blocking traffic). Often, you can just back up and the wheels will follow the path they made right back to the rails. And fortunately today, they did just that. But we lost half an hour chipping the rest of the ice out with steel bars and poles. Oh, and the avatar name. I earned that long before today.