公路隧道CO设计浓度限值的分析研究

现行规范中给出的CO设计浓度对隧道长度、人员不同通行方式的考虑过于粗略,且未考虑海拔高度的影响。本文分析了CO对人体危害的机理,通过Coburn-Forster-Kane模型分析了CO浓度与人体血液中产生的COHb浓度之间的关系,从而得出了公路隧道内经历时间与CO浓度限值之间的关系,并分析了海拔高度、通风方式以及人员不同通行方式对CO浓度限值的影响。通过分析结果可以看出,规范中规定的CO设计浓度在经历时间较长的情况下将不再适用,取值过高,应进行修正。本文分别计算出COHb浓度控制为2％和1.5％时,在不同海拔高度的公路隧道CO设计浓度限值,并整理成表格,可在公路隧道在通风设计中参考使用。

Study on the Upper Limit of CO Concentration in Highway Tunnel Design

The CO design concentration given in current code is too rough in consideration of the tunnel length and people passage way, and the influence of altitude is not considered. In this paper the mechanism of injury on human body by CO is analyzed. On the basis of Coburn-Forster-Kane model, the relationship between CO concentration and COHb concentration in human blood is analyzed. Then the relationship between the time passing through the tunnel by the vehicle and the CO concentration upper limit is obtained. The influence of altitude, ventilation type and people passage way on the CO concentration upper limit is also analyzed here. Results show that, design CO concentration given in current code is not applicable when the people stay in tunnel for a long time. The given value is too high, and need to be corrected. The design CO concentration limit is calculated for different altitudes under the COHb concentration value of 2% and 1.5% and the data are summarized in a table. The results can be a design reference for road tunnel ventilation system.