Research On Risk Analysis Of Driving And Prevention Measures For The Long-steep Downgrade Based On Truck Braking Performance

The mountain areas are full of river and canyon, geological condition of several areas isspecial, in order to overcome the height, there are several long-steep downhill sections ofExpressway in mountainous area. At the same time, in the mountainous area highway, about1/2of the accidents occurred, wherein, most accidents are major or serious accidents, andcause casualties. In view of this situation, the relevant departments have adopted a series ofmeasures, but some of the measures can not effectively play the role of. Thus, securityproblems in the long-steep downhill sections are more severe。In2013science and technologyproject of transportation hall in the province of Yunnan-" research on safety technology ofdangerous road in freeway under the coupling action of the plateau climate and complex roadconditions " funding, according to the present problems, based on in-depth analysis of theroad accident mechanism and prevention measures, combined with the study of truck brakingefficiency, the paper dispose comprehensive security measures of the long downhill relies onthe project, and the results will provide theoretical and practical guide for security measures inthe long-steep downhill sections。Firstly，the paper analyses the accident data and prevention measures of typicallong-steep downhill sections, combined with the driving characteristics of drivers, and basedon the distribution of the time of the accident, the vehicle of the accident, the shape of theaccident and so on，reveals the common characteristics and main causes of traffic accidents,and induces defects of the long-steep downhill sections safety facilities, provides direction forthe research of the risk analysis in the long-steep downhill sections.Secondly，based on section stress analysis of the truck in the downhill and the brake heat,heat dissipation mechanism of truck, combined with the current situation of application ofbrake auxiliary measures, this article analysis the forming method of the model, selects thebrake temperature model，and the paper applies the model calculate the temperature variation oftrucks’ brakes at different speed, load, brake initial temperature and gradient. The results showthat, under the same conditions, the higher the speed, the higher the load, the higher initialtemperature of the brake, the bigger the slope, faster growth of the temperature of the brake,the higher the temperature of brake at the bottom of the slope, the braking efficiency dropsmore, the more dangerous vehicle. The results of this study provide a scientific basis for theprevention and control measures of the long-steep downhill sections.Then, aiming at security truck brake efficiency good, through theoretical analysis andcomparison from the speed control method, traffic signs and markings setting, roadside safety, safety management, service facilities and other aspects, this paper puts forward the speed limitmethod sections and other auxiliary measures in the long-steep downhill sections,Finally, the paper takes Yunnan Pu Xuan expressway as an example, proposes thesecurity enforcement system of the long-steep downhill sections.