基于RHRS系统的景区落石风险评估与决策

RISK ASSESSMENT AND DECISION OF ROCKFALL IN SCENIC SPOT BASED ON RHRS SYSTEM

近年国内山地景区落石掉块现象常有发生,游客的生命安全受到严重威胁,因此对落石风险研究具有科学价值和重要社会效益。通过引入RHRS风险评估系统,针对两座样本景区,对可能导致落石灾害的各项影响因子(包括斜坡高度、地质特征、落石体积/块体大小、降雨量和历史落石频率等)进行较为深入的分析,根据原始评分公式进行风险评分,以综合分值来反映落石风险程度并结合风险允许标准划分高、中、低风险区域进行决策,将抽象的定性评价转为具体的定量评价,得到衢州药王山与江郎山两座样本景区的自然落石风险评分分别为142、117.2。采用FN曲线与ALARP原则相结合的方法来确定风险允许标准,计算我国可接受风险平均值为1.62×10-5/a,得到我们国家地质灾害可接受的风险水平FN曲线的上下限依次为10×10-4/a和10×10-5/a,为景区落石风险评估与决策提供借鉴。

Rock fall frequently happens in natural landscape scenic spot and imperils tourists. So it is of social and scientific significance to study the rock fall and collapse. RHRS risk evaluation system is used to analyze the various factors that can cause the rockfalls in scenic spots. They include slope height,geological characteristics,rockfall volume/block size,annual average rainfall,and historical rockfall frequency. In order to represent the extent of rockfall risk,the scores for rockfall risk are calculated with the original scoring formula to be 142 and 117. 2 for the King of Medicine Mountain and Jianglang Mountain in Quzhou province,respectively. In this process,the abstract qualitative evaluation is converted into a specific quantitative evaluation. The FN curves and ALARP principle are combined to determine the allowable risk criteria,as well as clearly divide the high,medium and low risk areas.The average acceptable risk calculated is 1. 62 × 10-5 per year. The upper and lower limits of the acceptable risk level on the FN curves are calculated as 10×10-4 per year and 10×10-5 per year respectively. The findings of this study can be used as a significant reference for rockfall risk evaluation and decision making in scenic spots.