【摘要】 高风险等级堰塞湖一旦失事,危害极大,合理的应急处置措施可避免堰塞湖对下游造成巨大的损失。"堰塞湖风险等级划分标准(SL450-2009)"规定,应急处置工作应建立在相应风险等级的一定重现期的洪水标准基础上。对于风险I级的堰塞湖,标准规定了"≥5年"的洪水重现期标准。鉴于这一等级包括了"极高危险"和"高危险、中危险"两个亚类,进一步为这两个亚类分别提出各自的洪水标准,有一定的现实意义。本文以属于"极高危险"的唐家山堰塞湖和红石岩堰塞湖实际采用的应急处置方案为例,反演各自开挖深13 m和8 m的引流槽相应的入库洪水,据此建议应急处置期对风险Ⅰ级的"极高危险"这一亚类的堰塞湖洪水重现期取20年为宜。此研究成果可供规范修改和处理类似堰塞湖参考。更多还原

【Abstract】 Failure of a barrier lake with a classified high risk will cause disastrous damage. Emergencymeasures are always necessary in order to mitigate the disasters. The code "Standard for classification ofrisk grade of landslide lake(SL 450-2009)" specifies that the emergency measures should be determinedbased on a flood with a certain level of return period,which is "≥5 years" for a grade I barrier lake.However this risk grade consists of two subgrades referred to as:"very high" and "high or moderatelyhigh". It is practically pertinent to assign details for this flood control system. This paper attempts to makeback analyses of the return period of two barrier lakes with the risk grade of "very high", which areTangjiashan and Hongshiyan that adopted diversion channels with excavated depths of 13 m and 8 m re-spectively. It has been found that a return period of 20 years can best explain these field experiences. Thisfinding may be consulted in code revision and other emergency mitigation works for barrier lakes.更多还原