二郎山公路隧道泥石流地质灾害及防治

1997年7月3日及8月15日暴雨期间，川藏公路二郎山隧道东口龙胆溪、西口和平沟暴发2次灾害性泥石流，造成隧道施工设施被毁、人员伤亡。泥石流形成机制、活动规律、演化趋势及相应防治措施的研究，对确保隧道施工及安全运行具有重要意义。论文以和平沟泥石流为例，在研究泥石流形成条件、活动特征基础上，分析了泥石流的形成机制及其造成巨大危害的原因，预测了泥石流的发展趋势，据此提出以排导工程为主，排导与拦挡工程相结合，工程措施与生物措施相结合的综合防治对策。研究表明，在山区公路隧道建设中泥石流的防治，必须建立在对地质灾害发育、分布、活动规律、形成演化机制及其危害性认识的基础上，这样才能在隧道选址、施工设计时，制订相宜、合理的防治对策。

The debris flow hazards of the tunnel in Erlang Mountain and its prevention

From July 3rd to August 15th 1997, the catastrophic debris flow hazard occurred two times in Longdan stream of the east entrance and heping stream of the west entrance of Erlang Mountain Tunnel, Chuan-Zang Road in the period of heavy storm. It has damaged the construction facilities and brought some personnel casualty. It hindered the tunnel construction seriously. It is very important for the tunnel safety in period of its construction and running to study the formation mechanism, activity rule, evolvement trend and prevention measures of debris flow. Based on the study of the formation condition and activity characteristics of Heping stream debris flow, the formation mechanism of the debris flow and its harm to the tunnel are analyzed, the development trend of debris flow is forecasted. Hereby, the prevention measures of debris flow are pointed out. This paper puts forward that the debris flow prevention must base on understading of the distribution, activity rule, formation mechanism and harmfulness of geologic hazard during building mountain highway tunnel.