高海拔特长公路隧道施工及运营通风关键参数研究

With the deepening development of highway construction, the highway tunnel construction has a trend of ‘high’ and ’long’, and there are more than 20 highway tunnels with the altitude over 3,000 meters in western Tibet. However, the increase of altitude has brought problems of anoxia, lack of requires airflow, and fan inefficiency to disturb the construction and operation ventilation of high-altitude highway tunnel. And these problems could seriously slow the construction progress, increase the project investment and endanger life safety. Thus the three problems in high-altitude highway tunnel which are both independent and interconnected need to be studied unified. Based on Queer Mountain Tunnel project with altitude of 4380m, Baimang Snow Mountain Tunnel project of 4070m and Balang Mountain Tunnel project of 3800m, our research aimed to get oxygen supplying standard in construction of high-altitude super-long high way tunnel, and establish the altitude coefficient calculation method considering the CO and smoke based on multi-factors and establish axial flow fan efficiency calculation method of high- altitude super-long highway tunnel through information research, theoretical derivation, numerical calculation and field measurement, and finally to solve the problems of anoxia, lack of requires airflow, and fan inefficiency due to the change of high-altitude. All above studies could provide basis for the operation and permanent ventilation of high-altitude high way tunnel, and also provide beneficial supplement for the revision of the relevant specification.

随着公路建设的不断深入，公路隧道建设有向“高、长”发展的趋势，西部藏区海拔高度超过3000m以上的公路隧道已超过20座。随着海拔的升高变化，在隧道施工及运营通风中出现了缺氧、需风量不足、风机效率低下三大困扰隧道施工及运营的难题，严重影响施工进度及增加项目投资，且危及人员生命安全，三者既相互独立又互相关联，需统一研究。本课题以海拔4380m的雀儿山隧道工程、海拔4070m的白茫雪山隧道、3800m的巴朗山隧道工程等为依托工程，通过资料调研、理论推导、数值计算、现场实测等手段获得高海拔特长公路隧道施工供氧标准，建立基于多因素的考虑CO和烟雾的海拔高度系数计算方法以及高海拔特长公路隧道轴流风机效率计算方法，从而解决由于海拔高度的改变引起的施工缺氧、需风量不足、风机效率低下等难题。上述研究可为高海拔公路隧道施工及运营通风设计提供依据，也为相关规范的修订提供有益的补充。

高海拔特长公路隧道由于气象环境的改变，在施工及运营通风中经常出现供氧不足以及设计风量不足，从而在施工及运营过程中危及洞内人员的安全。依托川西高原海拔超过3000m的特长公路隧道，对高海拔特长公路隧道施工及运营通风关键参数展开研究。研究内容包括以下三部分：（1）高海拔特长公路隧道供氧标准研究；（2）考虑CO和烟雾海拔高度系数规律研究；（3）高海拔特长公路隧道轴流风机效率规律研究。重点对施工通风中的风机效率、供氧标准等参数展开研究，建立了风机效率的海拔高度修正方法以及高海拔特长公路隧道供氧标准。在高海拔特长公路隧道运营通风研究中建立了海拔2400m以上的混合车型烟雾海拔高度系数计算方法和海拔2200m以上的混合车型CO海拔高度系数计算方法，同时对高海拔单洞双向特长公路隧道防灾救援技术进行了研究。研究成果已经部分运用于高海拔特长公路隧道通风设计中，保障了隧道施工及运营过程中人员的需氧及通风要求，研究成果具有重要的实际运用价值。