佛开高速公路改扩建工程交通组织分析

全面分析佛开高速公路改扩建工程实施全过程中对区域路网造成的影响,并提出了相应交通组织实施方案,以便有序地进行交通组织,不造成长时间的交通拥堵,实现交通的良性运行。     

道路通行能力中车道数因素的数学分析

在实地调研得出道路平均每车道通行能力随着车道数的增加而边际递减的基础上,参照流体力学的研究方法,得出考虑换道的车道交通流动力学模型.采用特征线分析法得到该模型的解析解.运用数学方法分析了边际递减的原因和递减的规律.并运用实测数据验证了数学解释的合理性,得出换道频率的增加是通行能力递减的主要原因.     

吴淞口邮轮码头交通组织设计

采用车道边论证方法进行吴淞口邮轮码头的交通组织设计,对极端工况下的车流量进行了定量分析,得出引桥交通量及码头面上的车位布置数等重要交通组织参数。并通过仿真方法证明交通组织方案的合理、有效,与理论计算互为补充。     

强制性换道的空间特征对分流区交通流的影响

为研究车辆在多车道分流区的跟驰换道行为，将强制性换道划分为激进型和保守型.在考虑驾驶员换道需求与空间位置关系的基础上，量化两种强制性换道行为的转换条件，并给出车辆强制性换道规则；对跟驰模型中的减速度参数进行优化，建立多车道下分流车辆的跟驰换道模型；采用实际数据标定模型中关键参数，并验证模型的可行性.仿真结果表明：分流车辆的横向空间分布对交通流的干扰具有显著性影响；当分流车辆集中在最左侧车道时，中间2车道的运行速度波动明显，折减量最大时达到51.4%，恢复稳定所需时间更多；通过 4组实验场景发现，分流车辆的合理空间分布对交通流运行速度有较大的改善作用.     

A problem of limited-access special lanes. Part II: Exploring remedies via simulation

Spatiotemporal analyses of freeway sites in Part I have shown that special-lane access points are prone to become bottlenecks. These can degrade traffic flows, sometimes in all lanes. Part II explores select impacts of re-designing the means of entering and exiting a special lane, and of altering the policy governing its use. Parametric tests were conducted using a computer simulation model that was calibrated to one of the sites studied in Part I; one with a buffer-separated carpool lane. Though less reliable than what might have been observed via experiments in real settings, the simulated findings seem to offer useful insights nonetheless.The findings indicate that traffic conditions would improve at the site by elongating the carpool lane’s buffer opening beyond its present length of 400 m. Yet, only modest improvements were predicted, even when the opening was elongated to 1000 m or more. Greater benefits were predicted from disentangling the movements made into and out of the carpool lane. This was achieved by placing first a buffer opening to serve only ingress, followed by another immediately downstream to serve egress. The benefits of this treatment were again limited, even when each tandem opening was elongated to a length of 700 m. Fully removing the buffer that physically separates the carpool lane from the regular ones was predicted to bring the greatest improvements to traffic. Also examined was pending legislation that would leave the carpool-lane buffer in place, while limiting the times of day when the lane is reserved for special use. Simulations predict that this legislation would degrade travel conditions below those that presently occur at the site. The extent of this predicted degradation varied, depending upon the time of day when the lane-use restriction went into effect.     

轨道列车时刻表问题研究综述

广泛的实践应用和复杂的计算挑战,使得轨道列车时刻表优化问题,多年来一直是交通运 输及运筹管理学界的热点研究问题。作为轨道交通运营规划的一个子阶段,列车时刻表向上与 线路规划(或开行方案)、向下与动车组调度融合,可以得到多个延伸的研究选题。在特定的时空 网络中,列车时刻表设计就是为每个列车确定一条无冲突的运行路径,使基于用户的度量指标如 乘客候车时间,或企业的度量指标如运营费用达到最优。对于没有列车越行和停站模式给定的 情况,通过整数变量可以完整地刻画列车时刻表模型,但如果考虑列车越行或列车停站决策,则 需要引入列车在车站出发顺序或停车决策的0-1变量。一般而言,列车时刻表问题的数学模型是 一类典型的大规模、多目标、强耦合的NP完全问题。算法设计是列车时刻表问题最为重要和困 难的部分。对于问题较简单或规模较小的情况,常用方法是对原有复杂问题进行适当简化和(或) 对难处理表达式进行合理修改,然后使用先进的计算架构和商用优化软件求解更新后模型。当 然,分支定界和动态规划这两类直接分解算法,是求解列车时刻表问题的重要方法。对于问题复 杂和规模庞大的情况,以拉格朗日和列生成为代表的对偶分解算法,则是求解列车时刻表问题的 最佳选择。未来,探讨列车时刻表与各种现实需要(如设施维修),以及时变票价和客票分配等因 素之间的深度融合,是一个有价值的研究方向;其次,研究网络环境下列车时刻表问题,将是一个 非常有意义的研究选题;最后,应进一步设计集成了问题特点与现代优化技术的各类求解算法, 开发能够完全应用于实际运营的商用软件。     

基于路阻函数的可变车道转换时机研究

针对“潮汐式”交通问题,探讨可变车道的实施流程和转换机理．基于BPR路阻函数建立了可变车道调整数量优化模型。该模型不仅能根据交通流状况计算出需要调整的车道数．而且可以针对不同的道路条件计算出可变车道适合的转换时机。最后,通过实例验证了模型的可行性。     

某双洞八车道隧道小净距优化的数值分析

以某双洞八车道小净距隧道为依托,从中间岩柱塑性区域、后行洞对先行洞位移及内力的影响等几个方面,探讨了各种围岩级别下四车道小净距隧道的最小净距的合理取值,对超大断面隧道的设计有一定的借鉴意义。     

中小城市摩托车专用车道设置与实用效果分析

摩托车因其自身的灵活便捷且出行成本低等优势,在国内依然有相当大的保有量。近年来,为解决摩托车的管理问题,国内大多数城市以简单禁令限制摩托车的发展。本文从技术管理的角度出发,在参考国内外摩托车管理模式的基础上,深入分析了摩托车、汽车混行道路上摩托车的交通特性,根据其行驶特性以及道路、交通流的不同条件组合,提出摩托车专用车道的设置方式,以提高道路交通安全水平、改善行车秩序。     

Capacity of Dual-Right-Turn Lanes at Signalized Intersections under Mixed Traffic Conditions

To explore the potential capacity of dual-right-turn lanes at signalized intersections under mixed traffic conditions, we defined two conflict zones between right turn vehicles and through bicycle corresponding to different right turn flows from dual-right-turn lanes. Relationships between the arrival rate of bicycle group at each conflict zone and the saturation flow rate of right turn movement were investigated. A model based on gap acceptance theory was adopted to estimate the capacity of dual-right-turn lanes under mixed traffic conditions. An analysis was carried out using the collected data from three four-leg signalized intersections in Beijing, China, where the dual-right-turn lanes were used. In addition, we also discussed the patterns of bicycle lane in the urban area of Beijing, and classified it based on its characteristics in use. It is concluded that the two lanes of dual-right-turn lanes produce different capacities under mixed traffic conditions, and the analysis on scenarios of dual-right-turn movement traversing bicycle traffic plays a key role in explaining the different capacity performance of the two right turn lanes. Error analysis of the model indicated that the model was rational.