大型公共建筑同向机动车出入口间距计算

为提高城市道路交通服务水平,提出大型公建同向机动车出入口间距计算方法.通过同向出入口影响区域构建,建立3个同向出入口最小间距模型.模型分别以保证车辆稳定行驶、减少直行车制动和协调相邻出入口车辆合流等交通行为为优化目标,相应地以出入口数量、直行车溢回率和合流距离等交通参数为约束条件.然后针对二分法算出的间距候选方案,利用基于交通仿真的拉开档次法进行评价优选.最后以某大型公建区域为算例进行结果分析.结果表明:与间距现状的评价结果相比,研究所得间距方案的组合评价值均较大；其中最优间距为172.92 m,对应最大组合评价值为0.874 3.可见该计算方法能够获得更优的间距方案,有利于大型公建同向机动车出入口布局定量优化.

Spacing calculation for same-side vehicle access of large public building

To heighten the traffic service level of urban streets,the spacing calculation method for the same-side vehicle access of large public building is put forward.By constructing the same-side access impact area,three same-side access minimum spacing models are established.The models separately take traffic behaviors,such as ensuring the vehicle steady running,reducing the through vehicle braking and coordinating the vehicle merging between the adjacent access,as the optimization objective.Correspondingly,proper values of traffic parameters,such as access number,through traffic spill-back rate and merging distance,are individually considered as the constraints of the models.Then aiming at candidate spacing schemes calculated by the dichotomy,the scatter degree method based on traffic simulation is used to evaluate for optimization.Finally,one large public building area is taken as a calculation example.Calculation results indicate that,compared with the evaluation result of the present spacing scheme,combination evaluation values of spacing schemes obtained from the research are all larger;there is an optimal spacing of 172.92 m,with corresponding largest combination evaluation value of 0.874 3.It can be seen that the calculation method can acquire the better spacing scheme,which is beneficial to the quantitative location optimization for the same-side vehicle access of large public building.