基于流量耦合分析的先出后入型快速路进出口方案设计

为确定先出后入型快速路进出口设计方案,考虑不同车流密度对通行能力计算模型的影响,计算不同的进出口车流条件下,快速路主路最外侧车道通行能力,通过对其分析比较以获取最佳快速路进出口设计方案,解决了目前的设计方案缺乏与流量耦合分析的问题。计算结果表明:当Q出<509pcu/h且Q入<509pcu/h时,采用出口道无减速车道-入口道无加速车道方案;当509pcu/h≤Q出<589pcu/h且509pcu/h≤Q入<589pcu/h时,采用出口道无减速车道-入口道设加速车道设计方案;当Q出≥589pcu/h且Q入≥589pcu/h时,采用出口道设减速车道-入口道设加速车道方案。

Design of Expressway by Using the Scheme of First-out and Second-in based on Flow Coupling Analysis

In order to determine the scheme of the exit and entrance of first - out and second -in urban expressway, the influence of different density on traffic capacity calculation model is considered. The traffic capacity of outermost lane at the main road under the different import flow and export flow is computed. By using the comparative analysis to get the best design, the problem lacking cou-pling analysis of a scheme is solved. The results show that when the export flow and import flow are less than 509 pcu/h, no decelera-tion lane is needed in the export and no acceleration lane is needed in the entrance road, when the export flow is from 509 pcu/h to 589 pcu/h, while the import flow is from 509 pcu/h to 589 pcu/h, an acceleration lane is required for entrance road and no deceleration lane is required for export road, when both the export flow and entrance flow are more than or equal to 589 pcu/h, an acceleration lane is required for entrance road and no deceleration lane is needed for export road.