多车道高速互通立交分流区交通冲突机理与分析方法

With the rapid growth of traffic volume, interchange diverge accidents will become a social focus on multi-lane expressway. But it has lack of targeted and operable evaluation index and evaluation method of safety on interchange diverge area currently. The traffic conflict technique has overcome the difficult of accident data collection, mature in the intersection. Interchange diverge area have the transportation conditions, necessity, theoretical basis and application prospects of traffic conflict technology introduction. The relevant research on analysis of interchange conflict mechanism and severity criteria is not deep enough, and no research literature of traffic conflict on diverge area. Therefore, the project has the novelty. Based on traffic flow observation and conflict mechanism analysis of multi-lane expressway interchange diverge area; the change regulation of traffic conflict was revealed in different conditions of the driving behavior, traffic flow characteristics and traffic management measures. The traffic conflict severity criteria were established based on non-complete braking distance, TTC time index and the driver physiological indexes. And then combined with accident reconstruction, the replacement relationship between serious conflicts and accidents has been verified. The traffic conflicts prediction model was established on interchange diverge area eventually, and the security analysis method and evaluation system of interchange diverge area based on traffic conflict formed.

随着交通量的迅速增长，多车道高速公路互通立交分流区事故必将成为社会关注的焦点。而当前互通立交分流区缺乏针对性和可操作性的安全评价指标和评价方法。交通冲突技术克服了事故数据采集困难的弊端，在平面交叉口领域已发展成熟。互通立交分流区具备引入交通冲突技术的交通环境条件、现实必要性、理论基础与应用前景。当前相关研究对互通立交冲突机理与严重性判定标准的分析不够深入，且未见分流区冲突研究的文献，故本项目具有新颖性。项目基于多车道高速公路互通立交分流区交通流观测与交通冲突机理分析，揭示不同的驾驶行为、交通流特性和交通管理措施情况下，交通冲突的变化规律。基于非完全制动距离、TTC时间指标和驾驶人生理指标，建立交通冲突严重性判定标准，进而结合事故再现验证了严重冲突与事故的替换性关系。最终建立互通立交分流区交通冲突预测模型，形成基于交通冲突的互通立交分流区安全分析方法与评价体系。

随着交通量的迅速增长，多车道高速公路互通立交分流区事故已成为社会关注的焦点。而当前互通立交分流区缺乏针对性和可操作性的安全评价指标和评价方法。交通冲突技术克服了事故数据采集困难的弊端，互通立交分流区具备引入交通冲突技术的交通环境条件、现实必要性、理论基础与应用前景。项目基于多车道高速公路互通立交分流区交通流观测与交通冲突机理分析，揭示了不同的驾驶行为、交通流特性和交通管理措施情况下，交通冲突的变化规律。通过对基于TTC时间指标的美国联邦公路局SSAM模型和相关课题冲突模型验证，分析了TTC指标的缺陷和避免碰撞减速度指标DRAC在反映驾驶行为和实际状况超出驾驶预期导致的操作不稳定性和接近事故的程度。结合实际减速度观测与事故统计，开展了冲突严重程度判别和冲突与事故替代性关系分析。利用标定后的仿真系统对不同交通量、交通组成、分流比、主线车道数、连接部出口车道数、减速车道长度、出口渠化措施等指标进行了正交仿真试验，分析了不同因素对冲突的影响程度，进而建立了分流区冲突预测模型。结合累积频率曲线分析法明确了分流区安全风险等级划分标准，形成了基于交通冲突的互通立交分流区安全分析方法与评价体系，可应用于既有运营阶段与设计阶段的多车道高速互通立交分流区的安全评价与安全改造。