城市道路平面交叉口非常规设计评价与优化方法

Constrained by the limited resources, the unconventional intersection designs have been proposed to reduce traffic conflicts, average traffic loads and improve the operational performance of prioritized traffic flow. However, the impacts of unconventional designs on the performance of at-grade intersections are still not clear due to the novelty and non-standardization of the unconventional designs. This study aims to: first, based on the investigation and data analysis, the impacts of unconventional designs on traffic behaviors of different roadway users are identified. Second, analytical models are established to evaluate the impacts of unconventional designs on the performance of at-grade intersections. Third, the synergy and trade-off among different objectives (operation, safety and environment) and among different roadway users (motorists, cyclists and pedestrians) are quantized. The multimodal level of service of the at-grade intersections with unconventional designs is calculated. Finally, to improve the multimodal level of service, an optimization method is proposed to determine the design parameters, with the constraint of the storage time and space resources, the priority rules, the management and control strategies at the intersection. Several examples are presented according to the proposed procedure. The research results of this study can provide theoretical guidance and key technical support for the implementation, optimization and modulation of unconventional intersection designs.

平面交叉口非常规设计根据交叉口存量时空资源约束条件进行特殊设计，以达到分离交通冲突点、均分交通负荷、保障优先交通流通畅运行的目的，但由于非常规设计方式的新颖性与不规范性，其实施效果尚不明晰。本课题通过动、静态交通时间与空间特性的调查与数据分析，揭示非常规设计对多方参与者行为影响机理，构建非常规设计对平面交叉口运行效能影响分析模型；量化表征评价指标在不同评价目标（效率、安全、环境）之间和不同方式参与者（机动车、非机动车、行人）之间的协同与悖反关系，提出平面交叉口非常规设计综合服务水平计算方法；以综合服务水平最优为目标，构建多方式资源分配协同优化模型，提出存量资源限制、优先规则与管控策略条件下的非常规设计参数优化方法，并通过交通模拟和实例分析进行验证和评价。本研究可为平面交叉口非常规设计方案的实施、优化和调整提供理论指导和关键技术支持。

本课题围绕我国城市交通可持续发展的需求，针对平面交叉口中存在的突出矛盾，论述非常规交叉口设计对于运行效率、交通环境、能源消耗以及交通安全的影响评价方法。针对典型非常规交叉口设计方式分析评价指标值与设计参数之间的数量转化关系，分析设计方式及设计参数对于评价指标的影响机理，为非常规交叉口设计问题的指标影响分析提供新视角。选取典型的设计方案，包括将次路停车控制交叉口变为次路让行控制交叉口、将次路停车控制交叉口变为四路停车控制交叉口以及将次路停车控制交叉口变为环形交叉口，分析在不同的交通条件下各设计方案及参数如何影响交叉口的交通运行状况，研究在不同的交通设计参数与交通条件下各评价指标之间的悖反关系。提出了基于成本效益分析的多目标综合评价方法，重点研究了效率指标和安全指标权重标定方法，即出行时间价值和事故经济损失计算方法。为考虑指标不确定性对评价结果的影响，提出基于蒙特卡洛仿真的多目标变权综合评价方法。依托信号交叉口左弯待转区设计、无信号交叉口交通改善设计、信号交叉口借道左转车道设计、人行过街交通设施设计四个典型案例对提出的非常规交叉口设计多目标综合评价及参数优化方法进行实例验证。