瓶颈路段公交和小汽车共享车道通行能力研究

城市空间紧缺,公交专用道通常通过转变现有普通车道获得。在城市道路瓶颈路段处,如果公交车发车频率较低,不仅公交专用道难以充分利用并造成道路空间的浪费,还会加重小汽车的延误。针对这个问题,国外已有研究在选定的瓶颈路段设置公交车和小汽车的共享车道方法。文中梳理了在相应的共享策略下瓶颈路段的通行能力计算方法,并考虑到小汽车在瓶颈处的扰动对通行能力的影响。通过对深圳市皇岗路与新彩路交叉口处入口匝道的仿真分析表明,当小汽车有低于20%驶入共享车道时,设置共享车道可以在不对公交车运行造成影响的情况下降低入口匝道和新彩路主线上的小汽车延误。但当小汽车驶入共享车道的比例大于20%时,对公交车的运行开始产生影响,并且对新彩路主线上的小汽车运行有一定的影响。随着小汽车驶入共享车道的比例继续增大,这种影响有呈指数增加的趋势,证明了车流的扰动因素对瓶颈通行能力有很大的影响。

A Capacity Analysis of Shared Bus/Car Lanes at Bottleneck Sections

In urban areas where space is preciously limited,bus lanes can be created only by the conversion of exist-ing general-use lanes.If buses depart at a low frequency,the bus lanes will be under-utilized and road space will be was-ted.At bottleneck sections,in particular,non-bus vehicles will suffer greater delays.The paper focuses on this issue by proposing bus/car shared lanes within the selected bottlenecks.A method to estimate the capacity of shared lanes is pro-posed while considering the impacts of cars.The intersection of Huanggang Road and Xincai Road in Shenzhen was simu-lated as a case study.The results indicate that the delays of cars decrease while the buses'level of service (LOS)remains unaffected when less than 20% cars drive into the shared lane.However,the LOSs for buses and cars both decrease when more than 20% of cars are in the shared lane The study also concludes that car traffic in the shared lane has a great impact on the bottleneck's capacity.The delays of cars increase exponentially as car volumes in the shared lane increases.