Study on rainy Weather Situation of Highway Based on Historical Rainfall Classification

The traffic system consists of people, vehicles and roads, as well as the environment around the road during driving. Weather has always been an important factor that cannot be ignored along with the highway. Good weather will bring good vision conditions and psychological conditions to drivers, while bad weather conditions will directly or indirectly affect the driver's operation or vehicle power performance. As one of the most common weather, many people neglect the harm of rainy days to highway driving safety. When the rain reaches a certain level, it will lead to water on the road surface and reduce the friction coefficient of the road surface. If the driver drives too fast at this time, it will be more prone to deviation. When it reaches extremely bad conditions, it can even destroy the subgrade and pavement, which directly causes immeasurable safety hazards. Based on the rainfall data corresponding to the rainfall events in the traffic environment in the past few years, this paper proposes a research method for the characteristics of rainy days, which uses the fuzzy recognition method to classify the rainfall types of rainy days, to study the development trend of rainy days. After obtaining the development trend function of the historical type of rainy days, we can determine the type of the rainy day event and the specific time period of the type by comparing the closeness of the function of the current observation value with time and the historical function, so as to achieve the purpose of forecasting the development trend of the current weather event. Taking the change rate of rainfall change as the characteristic function, we can further quantify the change range of rainfall, the key indicator representing the intensity of rainy days. This strategy model is applied to expressway speed management, which can provide a good reference for traffic managers to make speed limit decisions, and can clearly decide when to cancel the speed limit strategy or upgrade to the road closure strategy.