长江科学院院报 ›› 2020, Vol. 37 ›› Issue (10): 171-176.DOI: 10.11988/ckyyb.2019152376

• 川藏铁路横断山区山地灾害分析专栏 • 上一篇    下一篇

高寒小流域措普沟山洪风险分析

陈华勇1,2,3, 蒋良文4, 游勇1,3, 王科4, 张广泽4, 王涛1   

  1. 1.中国科学院水利部成都山地灾害与环境研究所 中国科学院山地灾害与地表过程重点实验室,成都 610041;
    2.中国科学院 青藏高原地球科学卓越创新中心,北京 100101;
    3.中国科学院大学,北京 100000;
    4.中铁二院工程集团有限责任公司,成都 610031
  • 收稿日期:2019-12-16 修回日期:2020-03-29 出版日期:2020-10-01 发布日期:2020-10-29
  • 作者简介:陈华勇(1982-),男,四川广汉人,研究员,博士,主要从事堰塞湖溃决机理与防治对策方面的研究。E-mail:hychen@imde.ac.cn
  • 基金资助:
    中国铁路总公司科技研究开发计划课题(2017G008-F);中国科学院重点部署项目(KFZD-SW-425);四川省重点研发项目(2019YFG0460);中国科学院山地所‘一三五’方向性项目(SDS-135-1701);中国科学院创新促进会项目(2017425)

Risk Analysis of Flash Flood in Cuopu Gully in High and Cold Mountain Area

CHEN Hua-yong1,2,3, JIANG Liang-wen4, YOU Yong1,3, WANG Ke4, ZHANG Guang-ze4, WANG Tao1   

  1. 1. Key Laboratory of Mountain Hazards and Land Surface Processes, Institute of Mountain hazards and Environment, CAS, Chengdu 610041, China;
    2. CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China;
    3. University of Chinese Academy of Sciences, Beijing 100000, China;
    4. China Railway Eryuan Engineering Group Co., Ltd., Chengdu 610031, China
  • Received:2019-12-16 Revised:2020-03-29 Online:2020-10-01 Published:2020-10-29

摘要: 已有山洪泥石流灾害的风险评估主要针对暴雨或者冰川融水激发条件下的风险评估,而当高寒山区流域源头存在冰湖发育时,如何考虑冰湖对下游铁路、公路等线性工程影响的研究并不多见。以巴塘县措普沟及其支沟上游绒伊措冰湖为例,在分析冰湖孕灾环境背景的基础上,通过遥感解译和详细的野外调查,获得了绒伊措冰湖几何参数与沟道断面特征参数;结合坝体结构与物质组成特征,分析了坝体结构的稳定性;依据措普流域水文计算成果,评估了山洪对拟建铁路的影响。研究表明:绒伊措冰湖坝体由坚硬的花岗岩组成,坝体完整性好,在不考虑高烈度地震等极端条件下,绒伊措冰湖坝体稳定性较好,发生溃决的可能性较小,绒伊措冰湖对下游拟建铁路的影响小;在考虑P=1%设计频率暴雨与冰川融水情景下,措普流域山洪洪峰流量为448 m3/s,桥位所处断面的平均流速2.75 m/s,水深4.62 m,与铁路梁底的高差为53.89 m,对铁路线路安全不构成威胁。

关键词: 绒伊措冰湖, 坝体稳定性, 洪水灾害, 风险分析, 流速, 水深

Abstract: Existing risk assessment of flood/debris flow disasters is based mainly on the analysis of heavy rainfall or glacier-melt water.In some areas,especially in high and cold mountainous areas with glacial lake developing,researches on the impact of glacial lakes on proposed railways, highways and other linear projects downstream are rarely reported. In this paper, the key geometric parameters of Rongyi glacier lake in the upstream catchment of Cuopu Gully and the characteristic parameters of channel section are obtained based on the analysis of the environmental conditions of the glacial lake via remote sensing interpretation and detailed field surveys. The structure and material composition of lake dam are analyzed, and the stability of the dam structure is analyzed. Moreover, according to hydrological calculation of Cuopu Gully catchment, the impact of flash flood on proposed railway project is evaluated. Results reveal that the dam of Rongyi glacier lake is composed of hard granite with good integrity, indicating small possibility of dam failure in the absence of extreme conditions such as highly intensive earthquake. In the scenario of P=1% design frequency rainfall in association with glacier-melt water, the peak flow of mountain flood in Cuopu gully catchment is 448 m3/s, the average flow velocity at the railway bridge section is about 2.75 m/s,and the water depth is about 4.62 m. According to the railway design, the elevation difference between the bottom of railway beam and the flow surface is 53.89 m,which is considered to be safe for the proposed railway.

Key words: Rongyi glacial lake, dam stability, flood hazards, risk analysis, flow velocity, flow depth

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