The invention discloses a divided-lane speed-limiting early warning indication method based on rainfall intensity. The method comprises the following steps: collecting monitored rainfall in a red line domain of a speed-limiting road and calculating the rainfall intensity; calculating the
road surface water film thickness of each lane based on the rainfall intensity value; calculating the safety critical vehicle speed of each lane based on the
road surface water film thickness of each lane; and issuing a
speed limit value of each lane based on the safety critical vehicle speed of each lane and an originally set
speed limit value of the road, and issuing a corresponding lane warning mark based on the water film thickness of each lane. The invention further discloses a divided lane speed limiting early warning indication
system based on the rainfall intensity. The
system comprises a rainfall monitoring module, a critical vehicle speed calculation module and a judgment display module. Different
speed limit information is issued for different lanes according to rainfall conditions in real time, the problems that rainfall
weather factors are neglected in existing speed limit management and road speed limit is set to be a fixed value according to road grades are solved, and the safety and
toughness of a road to cope with different rainfall weather are improved.