Is there a radius for the left turnaround

Query the civil engineering network information can be known, the traffic rules put forward in the "left turn big turn, right turn small turn" driving requirements. But the specification only points out the turning radius of the right turn, the U-turn and left turn is not a clear requirement.

Car U-turn notes there are U-turn signs marking the intersection can be U-turn, left-turn guided lanes, there is no sign prohibiting U-turn, you can cross the crosswalk using the left turn U-turn, double yellow line to the front of the crosswalk with a dotted line, you can use the left-turn area in front of the crosswalk in advance of the U-turn.