车队离散模型被用来描述交叉口下游交通量分布与上游交通量分布之间的关系,为信号协调控制等提供理论支持,能否准确描述异质交通流特征,并具备解析解是评判模型效果的关键.为此,提出兼具通用性和解析性的截断混合位相型分布(TMPH)拟合车辆行程车速,推导基于车辆速度服从截断混合PH分布的混合车队流量离散模型.基于实际调查数据的分析表明,截断混合位PH可以充分描述异质交通流状况下的车辆速度分布.通过将推导建立的混合车队离散模型与经典的Robertson流量模型、混合高斯模型和实际到达流量分布进行比较分析,结果表明,模型具有良好的解析解,能更准确地描述异质交通流的车队离散规律.
The platoon dispersion model is used to depict the relationship of the downstream flow profiles to upstream flow profiles, which could provide theoretical support for signal control and other applications. To evaluate the effect of the models, it is critical for them to accurately describe the characteristic of mixed traffic flow and possess an analytical solution. Here the truncated mixed phase distribution (TMPH) is proposed, which has the merits of universality and analyticity. Then we can obtain the mixed platoon flow dispersion model based on this distribution. By analyzing the field data, the TMPH can fully reflect the characteristics of mixed traffic flow. Then on this basis, we can derive the mixed platoon dispersion model. Furthermore, through the comparative analysis of the proposed model, Robertson' s model, mixed Gaussian model and actual arriving traffic flow distribution, we found that the proposed model not only has good analyticity, but also could better reflect the platoon dispersion laws of mixed traffic flow.