【摘要】 具有国防意义的川藏公路南线是中国内地连接西藏的主要交通要道,也是进藏公路中最危险的一条。在对该公路的典型地质灾害段(八宿—林芝段)进行工程地质调查后,由现场调查、专家经验、理论分析等综合集成对滚石发生频率进行了估计,并获得了 19 个滚石区在不同人类活动特征下遭遇滚石的年平均概率。通过遭遇滚石的概率及承灾体的易损性分析,还得到了车辆和行人经过不同滚石区时遭遇滚石而致命的风险。相应的风险评价结果表明:(1) 经过滚石区 Rm4,Rm5,Rs1,Rs4,Rs5,Rs10和 Rm7时因滚石而致命的风险水平是比较高的;(2) 由于八宿—林芝间的交通条件和人类活动特征变化不大,不同滚石区间的危险性评价在一定程度上与风险评价是一致的;(3) 考察区公路沿线滚石致命的风险远远高于发达国家或地区滑坡灾害的风险。更多还原

【Abstract】 The south line of the Chengdu-Lhasa highway,which is of great importance for national defence, is one of the two main transportation corridors connecting Tibet with the inland of China. As the most dangerous traffic route entering Tibet,a 430 km long highway section (from Paksho to Nyingtri) with typical geological hazard is investigated for frequent rockfall events. Firstly,based on the EGMS methodology, rockfall frequency is estimated by combining all the possible knowledge of site investigation,experience and theoretical analysis for 19 rockfall zones along the highway section,and annually averaged probability of rockfall events under three situations of immobile vehicles,mobile vehicles and foot passengers,is calculated by using Bernoulli formula. Secondly,probability of deaths resulting from rockfalls in the 19 zones is obtained from the encountering probability and vulnerability analysis for highway users. The risk assessment indicates that (1) fatal risk of passing rockfall zones Rm4,Rm5,Rs1,Rs4,Rs5,Rs10 and Rm7,is higher than that in other rockfall zones;(2) there are little differences in traffic conditions and human activities along the highway section,hence the hazard assessment for the rockfall zones has a result,to some degree,consistent with risk assessment;and (3) fatal risk of rockfalls along the highway section is prominently higher than that of landslide hazards in some developed countries or regions.更多还原