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With the further improvement of the road network in Shandong Province conversion works, road network gradually covered the hilly areas have higher requirements on the capacity of the route and traffic safety. The restrictions of the mountain, environmental protection work is difficult due to the complexity of the terrain, geological conditions and other factors, had larger and longer vertical grade or combination of slope sections have a greater impact on the traffic. Climbing lane, is set to become an important measure to increase the capacity of the sections, and to improve traffic safety. In this paper, based on a large number of measured data, the study car in various Gradient its free flow speed variation with the slope and slope length: the uphill vehicle for the same slope for the specific sections Zongpo traffic running status quo, the steeper the long slope, the greater the speed is reduced; longer the same slope, slope length, the vehicle slows more. Small passenger traveling in the 4% to 5% of the uphill sections, compared with the flat road to reduce much, but the truck when climbing steep slopes vehicle slows significantly, and just entering the uphill process section of slope length of the running speed especially after the speed of decline slowed, reduced to the last will achieve a stable, uniform traveling. Car power-to-weight ratio calculation model is proposed to select a the longitudinal slope design led models based on 15% of the car power-to-weight ratio as based on the laws of the car traveling uphill, and test program set to determine the power-to-weight ratio. Test data analysis, to determine the power-to-weight ratio of the dominant models of the eastern part of Shandong Province, truck (whichever 8.05kw / t) selection the Dongfeng EQ1228V19D2 truck as the dominant models for longitudinal slope design. Technical performance parameters, the application of principle of vehicle dynamics, research car uphill, longitudinal grade, vehicle speed, and speed to draw the power-to-weight ratio of with slope length variation, 8.05kw / t truck led car type in the different slopes of the acceleration, deceleration Slope climbing performance curve. Sections trucks average speed flat slope through field observations and analysis of the permissible speed fold reduction curve based on the relationship between the speed fold reduction and slope length, the mountain road slope length limit recommended value. The climbing lane setting depends mainly on the ramp on the minimum allowable speed value and capacity. Departure from the truck climbing performance, based on the power-to-weight ratio fold reduction 8.05kw / t curve and allow the speed climbing performance, set conditions and design specifications of the climbing lane mountain road.
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