????????????????????????????

高速公路匝道控制是一种通过限制进入高速公路车辆数来有效改善高速公路拥堵的交通控制方法。本文通过微观交通仿真对无匝道控制、定时控制及三种广泛应用的匝道控制算法（ALINEA、FLOW、Stratified Zone）进行比较评价。仿真采用AIMSUN NG软件，以澳大利亚昆士兰州太平洋快速路的仿真模型为基础测试模型。研究结果表明，基本的匝道控制可使路网能力比无控制时提高40%。就路网和高速公路主要线路能力而言，在正常的和高的交通需求条件下，ALINEA算法优于其他算法，Stratified Zone在提高入口匝道能力方面最优。就匝道入口能力而言，ALINEA算法的匝道入口能力最低，FLOW算法比Stratified Zone算法略优。本文用基尼系数（Gini coefficient）评价不同算法的道路使用者效用。结论还表明，匝道控制可使高速公路路网和入口匝道能力达到平衡。

DEVELOPMENT AND COMPARATIVE EVALUATION OF RAMP METERING ALGORITHMS USING MICROSCOPIC TRAFFIC SIMULATION

Freeway ramp meteringis an efficient freeway control that can ameliorate freeway congestion bylimitingthe number of vehicles enteringthefreeway.This study presents development and comparative evaluation of five ramp controls including no control,time-of-day plan and three well-known ramp metering algorithms;ALINEA,FLOWand Stratified Zone throughthe use of microscopic traffic simulation.Inthis paper,ramp controls were developed and evaluated using Microscopic Traffic Simulation,AIMSUNNG.The simulation model of the Pacific Motorwayin Queensland,Australia was used as a test-bed model.The results fromthe studyindicatedthat ramp metering basically was foundto be able toimprove network performances upto 40 percent comparedto no control.In terms of network andfreeway mainline performance,ALINEA was superior to other algorithms under both normal and hightraffic demand while Stratified Zone wasthe best algorithmfor on-ramp performance.Interms of on-ramp performance,ALINEAwasfoundto generatethelowest on-ramp performance.FLOW was founds lightly superior to Stratified Zone.However,thetrend was oppositefor on-ramp performance.Gini coefficient was appliedto measure the road user equity under the implementation of different algorithms.The results showedthat FLOWwas the most equitable algorithmwhile ALINEAwasthe worst.The results alsoindicatedthat network performance and on-ramp performance were trade-off in presence of ramp metering operation.