Research On The Design And Location Of Maintenance Zone Facilities Of Mountain-Expressway

Inevitably,different levels of road diseases will occur during the operation of expressways.In order to ensure the safe passage of vehicles and prolong the service life of the roads,maintenance tasks will become increasingly onerous.Generally,maintenance zone will have different influence on the traffic flow.However,the highway alignment conditions in mountainous areas are complex,which will superimpose the interference in the maintenance zone.If traffic safety measures are unreasonable,it is more likely to cause traffic accidents.Traffic safety facilities in the maintenance zone are not only the main channels for drivers to get the road information,also an important link to ensure the safety of traffic.Therefore,research on the design and location of maintenance zone facilities of mountain-expressway is of great significance for improving driving safety and personal safety of highway operators in mountainous area.Firstly,based on the major types of traffic signs in the operational areas of China and the relevant regulations of the Manual on Uniform Traffic Control Devices(MUTCD),traffic sign models of different shapes and colors were established to construct the mountain highway simulation environment and conduct Experiments were conducted to analyze the visual effect of traffic signs under different signs’ background color,shape and driving speed,and to optimize the design of the traffic sign support member color,sign shape and background color.Then,an eye tracker was used to test the real vehicle in the mountain-expressway maintenance zone,and the driver’s fixation points in the maintenance zone were taken as the research object,and an improved artificial bee colony algorithm was used for Kmeans clustering.The algorithm is improved and combined with the relationship between the number of categories and the distance between classes,the fixation area is divided,and the main objects in each area that can draw the attention of the driver are determined.Based on this,Markov chain theory is used to analyze the one-step shift rule of the fixation of the driver and the steady distribution of the fixation behavior,and to study the driver information search mode during the driving process in the maintenance zone.Secondly,according to the relationship between the driver’s fixation transition pattern characteristics,road information density,and driver information processing capability,the road information density is used as an evaluation index of the maintenance zone facility setting effect,and the road information of the maintenance work area is quantified;the traffic sign based on the maintenance work area is continuous.The characteristics of the fixation point of the driver’s fixation point and the characteristics of the steady distribution of the fixation behavior are set.The indicator of the steady distribution of the transfer coefficient is proposed,and the relationship model between the information density of the maintenance zone and the stable distribution transfer coefficient is established using the Levenberg-Marquart method.The information densities of highway sections in highway maintenance zones in the mountainous areas shall not be continuously set at more than 0.95 bit/m,and the evaluation grades for the setting effect of the facilities in the maintenance zone shall be divided.Next,combined with the highway alignment,from the optimization calculation of the front distance mountain expressway maintenance zone information facilities three aspects of sharp steep slope,tunnel and road interchange;based on UC-win/Road software to build a highway traffic environment,the establishment of pilot short-term memory attenuation model,put forward the driver to form a stable short memory time required for 13s～15s.And calculate the information facilities set distance.Finally,according to the current norms and research results,an optimization scheme for the operation of special sections of expressways in mountainous areas is summarized and set up to evaluate the effects,and a comparative analysis is made with the current specifications.