八车道高速公路互通式立交最小净距计算模型

Calculation model of minimum net distance between interchanges on eight-lane expressway

为解决目前路线设计规范中互通式立交最小净距规定值不适应八车道高速公路的问题,避免因互通式立交间距设置过近造成的交通紊乱和交通安全问题,通过分析八车道高速公路小间距互通式立交间车辆的运行特征和变道行为,构建了八车道高速公路互通式立交最小净距计算模型;运用概率论、微积分、可接受间隙理论及运动学相结合的方法,从等待和追赶可插入间隙角度分析了车辆从外侧车道换道至内侧车道、从内侧车道换道至外侧车道所需的长度,并结合现场调查数据对模型的关键参数进行了界定。结果表明:八车道高速公路互通式立交最小净距值宜为2.2km。

To solve the problem that the specified value of minimum net distance between inter- changes on design specification for highway alignment can＇t adapt to the eight-lane expressway, and avoid traffic disorder and safety issues caused by the short distance between interchanges, the traffic operation characteristics and lane changing maneuvers were analyzed, the calculation model of minimum net distance between interchanges on eight-lane expressway was constructed. Combi- ning probability theory, calculus, gap acceptance theory and kinematics, the necessary lengths that drivers change to the inside lane from the outside lane and change to the outside lane from the inside lane were respectively analyzed in terms of waiting and running for the gap acceptance, the key parameters were defined based on field survey. The results show that the minimum net distance between interchanges on eight-lane expressway is 2.2 km. 3 tabs, 3 figs, 11 refs.