The pilot reported that, during the landing roll on runway 30, about 10 miles per hour, in gusting wind conditions, the airplane exited the right side of the runway and collided with a drainage culvert and nosed over. The airplane sustained substantial damage to the left-wing lift strut, the rudder and the vertical stabilizer. The METAR at the accident airport reported that about the time of the accident, the wind was from 240° at 27 kts and gusting to 40 kts. The manufacturer's pilot operating handbook specified that the maximum demonstrated crosswind component during takeoff or landing was 15 knots. The calculated crosswind component for the specified conditions was 29 knots. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.