Study Of Freeway Work Zone's Traffic Organization Programes Evaluation Based On Traffic Simulation

Highway is characterized by high driving speed, great traffic capacity, safety and comfortable, obvious economic benefits and so on, has been an important constituent of worldwide transportation system. Highway brings lots of convenience to people, meanwhile, emerges pavement and traffic facilities damaged etc for the reason of reaching to its actual working life, and thus causes highway maintenance engineering gradually increasing, and the research of traffic organization in maintenance section correspondingly growing. Existing research work mainly focused on determination and optimization of section form, speed limits, traffic sign and marking settings etc, however, there is greater limitations and certain blindness in the raising of highway traffic organization project assignments section, which has great differences in traffic, vehicle composition and road section of differences form etc, hard to give full play to highway economic and social benefits, for the scheme formulation, evaluation and optimization in section traffic organization lack of systematic research at the moment.Through the analysis of transportation characteristics and driving dangers in the highway section, combined with highway section traffic capacity, the driver driving safety requirements and certainty principle of traffic organization scheme, according to the construction technical specification and existing mature construction experience, the paper determines the highway section traffic organization scheme; according to traffic flow characteristics of assignments section and the factors Influencing section traffic organization form, the paper sets up traffic organization scheme evaluation system in the highway section, and assesses it and using traffic simulation software vissim, then draws the main conclusions as follows:(1) Based on the analysis of transportation characteristics and driving dangers in the highway section, combined with highway section traffic capacity, the driver driving safety requirements and certainty principle of traffic organization scheme, according to the construction technical specification and existing mature construction experience, the paper determines typical the two-way four lanes highway section traffic organization scheme, and gives the calculation method, limiting speed size and the settings of traffic sign and safety facilities of each section length;(2) From the factors influencing the implementation effect in the highway section traffic organization scheme, according to traffic flow characteristics of assignments section and common traffic scheme evaluation index system, the paper assesses traffic organization scheme from three aspects—traffic environment of assignments section, economic benefit assessment and traffic service level, and determines section transportation capacity, average speed etc fourteen evaluation indexes according to the influenced range of various aspects, then analyses the weights of each evaluation index to section traffic running, finally determines section construction saturation, average speed, traffic density and average travel delay as evaluation indexes of section traffic organization scheme according to the select principle of evaluation index;(3) According to the traffic scheme evaluation index system and service level index limits based on sections running status indicators and the weights of each evaluation index to section traffic running home and abroad, the paper divides the results of assessment indexes into five levels as excellent, good, general, comparing poor and poor; and chooses dynamic comprehensive evaluation method to assess the highway section traffic organization scheme combined with dynamic characteristics of evaluation index, through the comparison in evaluation object properties, applicable condition and applicability for common evaluation method;(4) Through the comparison of applicability in traffic facilities describing and vehicle behavior simulation for traffic simulation system, combined with the requirements of section traffic flow characteristics description, the paper chooses vissim as simulation software; and uses vissim to establish simulation model according to the traffic organization scheme, and uses dynamic comprehensive evaluation method to assess the highway section traffic organization scheme according to the simulation results, then draws conclusion that it is effective to assess highway section traffic organization scheme by means of traffic simulation, and achievable to raise corresponding improvement measure and optimize highway section traffic organization scheme according to the simulation results.This paper strives to validate it by means of the simulation technology and propose effective improvement measures through the simulation results, before the implementation of highway section traffic organization scheme; thus, it is beneficial to reduce the construction cost and has important significances for improving driving safety level and service level of highway section traffic organization scheme.