Link cost function and link capacity are critical factors in traffic assignment modeling. Popular link cost functions like the Bureau of Public Roads (BPR) function have well-known drawbacks and are not suitable for mixed traffic conditions where a variety of vehicle classes use the road in a non-lane-based movement. Similarly, capacity is generally considered as a constant value. However, in mixed traffic conditions, capacity is not constant, but a function of vehicle class composition. Toward addressing these issues, this paper proposes a link cost function in relation to link travel time and link capacity in relation to vehicular traffic flow for mixed traffic conditions. The functions are developed based on the kinematic wave model, which is popularly used for estimating traffic dynamics on the roads. The developed link cost function and link capacity use field measurable parameters that incorporate mixed traffic features. The functions are validated against empirical data obtained from 12 signal cycles from two different signalized intersections in Chennai, India, representing different scenarios of mixed traffic, and it was found that the results match well with the empirical data.

链路成本函数和链路容量是流量分配建模中的关键因素。诸如公共道路局（BPR）功能之类的流行链接成本功能具有众所周知的缺点，并且不适用于混合交通状况，在这种交通状况中，各种车辆类别均以非车道行驶方式使用道路。类似地，容量通常被认为是恒定值。然而，在混合交通状况下，容量不是恒定的，而是车辆类别组成的函数。为了解决这些问题，本文提出了一种针对混合交通条件的，与交通时间和交通能力相关的交通成本函数。这些功能是基于运动波模型开发的，该模型通常用于估算道路上的交通动态。开发的链路成本函数和链路容量使用结合了混合流量功能的现场可测量参数。根据从印度钦奈的两个不同信号交叉口的12个信号周期获得的经验数据对函数进行了验证，这些信号交叉口代表了混合交通的不同场景，并且发现结果与经验数据非常吻合。