ABSTRACT

This study developed operating speed prediction models on tangents, curves, and tangent-to-curve transitions for heavy passenger vehicles (HPVs), using continuous speed profiles. Continuous speed profile data for HPVs were collected on two-lane rural highway sections, spanning a total length of 77 km. The curve radius, degree of curve, and preceding tangent length were found to be the influencing variables in predicting both the operating speed on the horizontal curves and the operating speed differential from tangent-to-curve transitions. The study also modeled the relationship between the differential of the 85^th percentile operating speed $(\mathrm{\Delta }{V}_{85})$ and 85^th percentile operating speed differential $\left({\mathrm{\Delta }}_{85}V\right)$. The analysis results from empirical data revealed that $\mathrm{\Delta }{V}_{85}$ underestimates ${\mathrm{\Delta }}_{85}V$ by 5.01 km/h. The reliability of the developed models was validated and compared with existing models from literature. The study highlights the significance of using continuous speed profile data to calibrate the operating speed models.

摘要

本研究使用连续速度剖面开发了重型乘用车 (HPV) 的切线、曲线和切线到曲线过渡的运行速度预测模型。在全长 77 公里的两车道农村公路路段上收集了 HPV 的连续速度剖面数据。发现曲线半径、曲线度和前切线长度是预测水平曲线上的运行速度和切线到曲线过渡的运行速度差的影响变量。^{该研究还模拟了第 85个}百分位运行速度的差异之间的关系$(\mathrm{\Delta }{五}_{85})$和第 85^个百分位的运行速度差$\left({\mathrm{\Delta }}_{85}五\right)$. 经验数据的分析结果表明，$\mathrm{\Delta }{五}_{85}$ 低估 ${\mathrm{\Delta }}_{85}五$5.01 公里/小时。对所开发模型的可靠性进行了验证，并与文献中的现有模型进行了比较。该研究强调了使用连续速度剖面数据来校准运行速度模型的重要性。