Former studies revealed that before spillbacks happen intersection capacities can still be greatly affected by downstream queues and signals. However, there is no methodology reasonably accounting for this effect. This research aims to propose adjustment factor models (Adj models) for both saturation flow rate (SFR) and start-up lost time (SLT) in through lane groups considering downstream conditions. An improved cell transmission model is created to build a simulation platform that can well reproduce the downstream influence. By the experimental data, Adj models are derived through heuristic optimisation based regression analyses. Proposed adjustment factors are governed by common traffic indicators. Sensitivity analyses proved that approaches with high volumes, short segment lengths, large green ratios, positive offset, or large cycle lengths are more easily affected by downstream conditions. Through the validation, it is proved that the estimation error of SFR and SLT can be significantly reduced by the proposed adjustment factors.

以前的研究表明，在回溢发生之前，交叉口通行能力仍然会受到下游队列和信号的很大影响。但是，没有合理的方法来解释这种影响。本研究旨在提出考虑下游条件的直通车道组中饱和流量 (SFR) 和启动损失时间 (SLT) 的调整因子模型（Adj 模型）。创建了改进的细胞传输模型，以构建能够很好地再现下游影响的仿真平台。根据实验数据，Adj 模型是通过基于启发式优化的回归分析得出的。拟议的调整因素受共同交通指标的制约。敏感性分析证明，具有高容量、短段长度、大绿色比率、正偏移的方法，或大周期长度更容易受到下游条件的影响。通过验证，证明了所提出的调整因子可以显着降低SFR和SLT的估计误差。