Study On One-way Closed Construction Organization Technology In Highway Construction Area

Since 1988,China ’s first highway-Hujia Highway has been built and landed for 33 years.During this period,China ’s highway has developed rapidly,and the national highway mileage has already ranked first in the world.However,with the rapid development,there are problems such as road pavement damage,road facilities aging and insufficient capacity.Therefore,highway maintenance and expansion construction is an inevitable problem.During the construction of highway,the reduction of lane number,the change of vehicle driving path and the speed limit in construction area caused by construction are bound to reduce the service level of roads.Therefore,in order to protect the smooth progress of construction and ensure the safety and smoothness of roads,it is necessary to consider the overall traffic organization in the construction process,which is also the purpose of this paper.Firstly,this paper starts with the relevant literature and the basic theory of the constr uction area,and analyzes the basic characteristics and traffic characteristics of the constr uction area.The semi-closed construction area of the expressway is mainly divided into semi-one-way construction area and semi-two-way construction area.Secondly,the traf fic volume data of domestic related roads are investigated and analyzed to provide theor etical basis and data support for the optimization of traffic organization in the constructi on area below.Then the principle of traffic organization and the content of traffic organi zation scheme are expounded.The half-closed traffic organization scheme of constructi on area mainly includes the traffic diversion of construction area at the macro level,the design of closure time scheme and the layout scheme of construction area at the micro l evel.At the macro level,the closure time model and layer-by-layer diversion scheme based on traffic benefit are established,and the traffic organization scheme at the macro level is demonstrated with the example of Wenzhou South-Wanquan Section of YongtaiWenzhou Highway.Secondly,a reasonable evaluation system for the traffic organization scheme of highway construction area is established,and saturation,average speed,average delay,traffic density and MSDE value are selected as the evaluation indexes of the traffic organization scheme of construction area.On the micro level,combined with existing research and norms,based on the role of each section of the construction area itself,the length calculation model is analyzed and studied by mathematical theory and method.It is found that insufficient spacing is the main reason for highway accidents in recent years,so the calculation method of warning zone length is to control the minimum length of speed limit zone and the length of transition zone between speed limit zones from the perspective of speed limit.The upstream transition zone is based on traffic volume,speed limit and other factors to study the probability of the closed lane successfully entering the non-closed lane,so as to set the length of the upstream transition zone.The opening length of the intermediate belt is mainly to derive the calculation model of the opening length of the intermediate belt according to the requirement that the Sshaped driving trajectory of the vehicle here should meet the minimum radius of the circular curve and the driver ’ s driving experience.Finally,according to the above research and the field data of Cangnan-Guanmei section of Yongtaiwen Highway,two different construction area layout schemes are established based on VISSIM simulation platform.The service level evaluation and safety evaluation of the two schemes are carried out respectively.It is found that the MSDE value of the construction area is increased by 15.45 % under the same level of service level as the 《Highway maintenance safety regulations》 scheme.