城市下穿隧道纵坡坡度和速度对驾驶人心率增长率的影响

Effect of Slope and Velocity on Drivers' Heart Rate Growth in Urban Underpass Tunnel Longitudinal Section

为研究城市下穿隧道纵坡段驾驶人生理和行为特征变化规律,选取22名驾驶人在早晨5:00至7:00非高峰时段,交通状况几乎无差别的环境下,开展城市下穿隧道纵坡段实车试验。利用MP150生理测试仪和ECU车速采集设备采集驾驶人的心率值和车速值,应用单因素方差分析对数据进行差异性显著检验;并分析城市下穿隧道纵坡坡度和速度对驾驶人心率增长率的影响规律,构建城市下穿隧道上下坡段坡度、速度和驾驶人心率增长率关系度量模型,量化了坡度、速度与驾驶人心率增长率之间的关系。然后采用单因素敏感性分析方法对模型中的2个自变量(坡度和速度)进行敏感性分析。结果表明:在城市下穿隧道上、下坡段行驶时,不同坡度范围下的车速和心率增长率有一定的差异性,车速和心率增长率均随坡度增大呈现先增加后减少的趋势;城市下穿隧道上、下坡段,车辆速度均是在3.5%~4.0%坡度范围下的达到最大,在城市下穿隧道上坡段行驶时,3.5%~4.0%坡度范围下的驾驶人心率增长率达到最大,而在下坡段行驶时,4.0%~4.5%坡度范围下的驾驶人心率增长率达到最大;驾驶人在城市下穿隧道下坡段行驶时,心率增长率均值均高于上坡段,驾驶人在城市下穿隧道下坡段行驶时比上坡段更紧张;驾驶人心率增长率对坡度敏感程度要高于其对速度的敏感程度,坡度的变动比速度更易引起驾驶人心率增长率的变动,驾驶人的心理紧张程度受坡度的影响较大。

To study the change in physiological and behavioral characteristics in the longitudinal section of an urban underpass tunnel, 22 drivers were selected to performan experiment at off- peak hours from 5：00 to 7：00 in the morning, wherethe traffic conditions are almost the same in the longitudinal section of the urban underpass tunnel. An MP150 multiconductivity physiological recorder and the speed acquisition equipment were employed to record and analyze the drivers＇heart rate and speed. Significant differences in the experimental data were tested using the one- way analysis of variance （ANOVA） method, and the drivers＇ heart rate growth by the law of the urban underpass tunnel longitudinal section affected by velocity and slope was analyzed. Subsequently, the quantitative model of the drivers＇ heart rate growth, slope, and velocity was established; further, the relationship between slope, speed, and the driver＇s heart rate growth rate was quantified. The sensitivity analysis of two independent variables （slope and velocity） in the model was performed by the single factor sensitivity analysis method. The results show that when the driver was driving on the urban underpass tunnel longitudinal section, a statistically significant difference was found among different slope ranges on the velocity and the drivers＇ heart rate growth;as the slope increased, both the velocity and the drivers＇ heart rate growth would first increase and then decrease. In both the uphill and downhill sections of an urban underpass tunnel, the velocity is at the maximum in the 3.5 %-4.0 - slope range. On the uphill section, the drivers＇ heart rate growth reached the maximum in the 3.5 %-4.0% slope range; however, on the downhill section, the drivers＇ heart rate growth reached the maximum in the 4.0%-4.5% slope range. The drivers＇ heart rate growth on the tunnel downhill is significantly higher than that on the uphill, indicating that drivers are more nervous while driving downhill. Finally, the driver＇s heart rate growth is more sensitive to the higher slope higher than to the velocity. The slope change is more likely to cause the driver＇s heart rate growth rate to change, and the driver＇s psychological stress level is affected more by the slope.