Research On Traffic Safety And Protection Technology In Work Zone Of Expressway Reconstruction And Extension Engineering

With the rapid increase in the number of vehicles year after year,reconstruction and expansion project of the highway has become one of the major construction projects,and how to maintain the smooth traffic safety in the work zone is one of the major challenges currently faced.Compared with the newly built expressway,the reconstruction and expansion project has a more complex and obvious feature of traffic organization,especially the research on the safety and security technology of the work zone involves less.This paper studies the characteristics of traffic flow parameters,traffic capacity and space layout,and traffic safety evaluation in the reconstruction and expansion work areas of highways,and combines field research and simulation analysis to provide a certain application support for the deployment of the work zone of the reconstruction project.Firstly,based on the data from the field survey,the traffic characteristics of the highway reconstruction and expansion work zones were analyzed.Traffic simulations were performed on eleven types of work zones to obtain the effect of the basic form of the two-way four-lane and two-way six-lane operation area on the speed and capacity of the work zone,and also the different speed limit conditions.Under the impact of traffic capacity and based on the study of the relationship between different simulation traffic and the ratio of trucks to get the maximum cross-section capacity,established a non-linear regression based on the impact of mixed models of trucks.Then,using the theoretical calculation method,five recommended lengths for the warning zone,the transition zone,the central divider opening,the downstream transition zone,and the termination zone in the reconstruction and expansion work zone are given.Then the maximum length of the construction area was studied through simulation and combined with the influence of the mixed rate of trucks.The maximum length of the construction area was given under the conditions of different truck ratios.At the same time,the suggested values for the spacing between adjacent construction areas were obtained through simulation.Finally,the traffic safety evaluation of the operation area was carried out from the three aspects of traffic service level,traffic risk control and construction impact on the surrounding environment.Based on the Analytic Hierarchy Process(AHP)method,the evaluation indicators are weighted,the evaluation threshold criteria for each evaluation index are determined,and the corresponding fuzzy membership functions and evaluation grades are established,thereby establishing a multi-layer fuzzy comprehensive evaluation method for highway reconstruction and expansion project operation area traffic.Safety evaluation system.In addition,the research of this paper is applied to the actual project of a high-speed reconstruction project in Guangdong Province,and has achieved good results,which verifies the effectiveness of the traffic safety evaluation system in the operation area of the reconstruction and extension project proposed in this paper.