Research On Effect Of Vehicle Speed On Driving Safety On Two-lane Mountainous Highway

China is a mountainous country, and the mountain road occupies a large proportionof the total length in the country. Affected by the landform, its road alignment iscomplicated. The traffic accident rate on the mountainous road is very high, especially alarge propotion of serious accidents. Facing the serious security situation, the domesticand foreign scholars take research on the vehicle driving safety of the mountain road,especially the effect of vehicle speed, speed gradient and road alignment on the drivingsafety.For the need of analyzing the vehicle driving safety, road alignment design based ongeometric parameters (slope and turning radius) could be divided into four basic types ofgeometric road, namely straight segment, longitudinal curve segment, horizontal curvesegment and curved slope segment. Combined with the forces of the vehicle under allkinds of basic types of roads, vehicle speed prediction model is developed.When vehicle drives on the road, the actual speed will be affected by roadsideclearance, road conditions, the number of lanes, the climate conditions and roadenvironment factors such as road safety infrastructure. Considering all the factors asabove mentioned, the speed prediction model was revised to get the actual vehicleoperating speed, and finally analyzing the vehicle driving safety..Utilizing the experiment platform which comes from the National Natural FundProject "collaborative evolution of safe state between vehicle and road", the test data suchas the curve radius, elevation and vehicle speed were collected, and then the database wasgiven. According to the vehicle speed prediction model, taking three segments as likeK7600~K7900、K42900~K43200and K47200~K47500as examples, and getting the vehicle simulation speed on the road sections. According to the investion of roadsidewidth, road condition, lane number, climate condition and road infrastructure, thecorrection coefficient was ascertained, the vehicle’s actual running speed on the road wasobtained, and the operating speed was gotten.Combining the vehicle design speed on the road, the dangerous sections wereascertained. Through analyzing the dangerous road section, the reasons were found forthe driving danger. Rational advices (measures) were given for the vehicle driving safetyon the dangerous road section.