红石河堰塞湖漫顶溃坝风险评估
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摘要
四川省青川县红石河堰塞湖是2008年5月12日汶川大地震形成的34座大型堰塞湖之一,是由东河口滑坡堵塞红石河形成的。该堰塞体高度约50m、宽度约250m、顺河向长度约500m、形成的最大库容约400万m3。本文作者对红石河堰塞体做了较详尽的现场试验,包括土的冲蚀试验、土的基本物性试验等。基于现场试验数据,对土的冲蚀性和漫顶溃坝风险做了详细的分析。结果显示,从土的抗冲蚀性角度考虑,只要有水溢出就会有土体被冲蚀,这说明红石河堰塞体的漫顶溃决可能性较高。本文还提出经验公式来预测红石河堰塞体漫顶的溃决时间,大约为4.5d,如果考虑到大石块对抗冲蚀稳定性的有利影响,这一数值会增大。此外,还研究了溃决深度随时间的变化规律。
The Hongshihe landslide dam,located at Qingchuan County,Sichuan Province,is one of the 34 large-scale landslide dams induced by the Great Wenchuan Earthquake on May 12,2008.The Hongshi River was blocked by the Donghekou Landslide.The landslide debris formed the Hongshihe landslide dam approximately 50 m in height,250 m in width,500 m in length along the river.The dam reservoir capacity was estimated to be 6×106m3.Field tests were conducted at the Hongshihe landslide dam after its breaching.The tests include soil erodibility tests and basic soil property tests.Based on in situ soil erosion resistance data,the breaching failure risk was studied.It is shown that the landslide soils can be eroded as long as there is overflow,which means the overtopping breaching failure risk of the Hongshihe landslide dam is quite high.Moreover,the breaching time is evaluated based on newly introduced empirical equations and is about 4.5 days.As the presence of boulders is not included in the analysis,the actual failure time could be longer than our estimation.The trend of soil erosion depth with time is also investigated.The methodology presented in the paper may provide some guidance in handling similar incidences in the future.
The Hongshihe landslide dam,located at Qingchuan County,Sichuan Province,is one of the 34 large-scale landslide dams induced by the Great Wenchuan Earthquake on May 12,2008.The Hongshi River was blocked by the Donghekou Landslide.The landslide debris formed the Hongshihe landslide dam approximately 50 m in height,250 m in width,500 m in length along the river.The dam reservoir capacity was estimated to be 6×106m3.Field tests were conducted at the Hongshihe landslide dam after its breaching.The tests include soil erodibility tests and basic soil property tests.Based on in situ soil erosion resistance data,the breaching failure risk was studied.It is shown that the landslide soils can be eroded as long as there is overflow,which means the overtopping breaching failure risk of the Hongshihe landslide dam is quite high.Moreover,the breaching time is evaluated based on newly introduced empirical equations and is about 4.5 days.As the presence of boulders is not included in the analysis,the actual failure time could be longer than our estimation.The trend of soil erosion depth with time is also investigated.The methodology presented in the paper may provide some guidance in handling similar incidences in the future.
引文
[1]Costa J E,Schuster R L.The formation and failure of natural dams[J].Ceological Society of America Bulletin,1988,(100):1054～1068.
[2]Schuster R L,Costa J E.A perspective on landslide dams[A].Geotechnical Special Publication,1986,(3):1～20.
[3]柴贺军,刘汉超,张倬元,刘浩吾.天然土石坝稳定性初步研究[J].地质科技情报,2001,20(1):77～81.Chai Hejun,et al..Preliminary stability analysis of natural rock-fill dams resulting from landslides.Geological Science and Tech-nology Information,2001,20(1):77～81.
[4]Wan C F,Fell R.Investigation of rate of erosion of soils in em-bankment dams[J].Journal of Geotechnical and Geoenvironmen-tal Engineering,2004,130(4):373～380.
[5]Briaud J L,Chen H C,Govindassamy A V,Storesund R.Levee erosion by overtopping in New Orleans during the Katrina Hurri-cane[J].Journal of Geotechnical and Geoenvironmental Engineer-ing,2008,134(5):618～632.
[6]黄润秋,王士天,张倬元,刘汉超.中国西南地壳浅表层动力学过程及其工程环境效应分析[M].四川大学出版社,2001.Huang Runqiu,Wang Shitian,Zhang Zhuoyuan,Liu Hanchao.The dynamic process of earth’s superficial crust and its engineer-ing environmental effects.Sichuan University Press,2001.
[7]谢和平,邓建辉,等.汶川大地震灾害与灾后重建的岩土工程问题[J].岩石力学与工程学报,2008,27(9):1781～1791.Xie Heping,et al..Wenchuan Large earthquake and post-earth-quake reconstruction-related geotechnical problems.Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781～1791.
[8]http://www.cnqc.gov.cn/oa/dhkdzyz.nsf/maindir[EB/OL].(2008-12-1).
[9]任馨,党永平.青川县堰塞湖应急排险施工组织及管理[J].水利水电技术,2008,39(8):27～30.Ren Xin,Dang Yongping.Construction organization and construc-tion management for emergency risk-elimination of landslide dams in Qingchuan County.Water Resources and Hydropower Engineer-ing,2008,39(8):27～30.
[10]Hanson G J.Surface erodibility of earthen channels at high stresses part II-developing an in situ testing devices[J].Transactions A-merican Society of Agriculture Engineers,1990,33(1):132～137.
[11]Hanson G J,Simon A.Erodibility of cohesive streambeds in the loess area of the Midwestern USA[J].Hydrological Processes,2001,(15):23～38.
[12]Chien N,Wan Z H.Mechanics of sediment transport[M].ASCE Press,Virginia.1999.
[13]Hanson G J.Surface erodibility of earthen channels at high stres-ses part I-open channel testing[J].Transactions American So-ciety of Agriculture Engineers,1990,33(1):127～131.
[14]Simons D B,Senturk F.Sediment transport technology[M].Water Recources Publications,Colorado,1971.
[2]Schuster R L,Costa J E.A perspective on landslide dams[A].Geotechnical Special Publication,1986,(3):1～20.
[3]柴贺军,刘汉超,张倬元,刘浩吾.天然土石坝稳定性初步研究[J].地质科技情报,2001,20(1):77～81.Chai Hejun,et al..Preliminary stability analysis of natural rock-fill dams resulting from landslides.Geological Science and Tech-nology Information,2001,20(1):77～81.
[4]Wan C F,Fell R.Investigation of rate of erosion of soils in em-bankment dams[J].Journal of Geotechnical and Geoenvironmen-tal Engineering,2004,130(4):373～380.
[5]Briaud J L,Chen H C,Govindassamy A V,Storesund R.Levee erosion by overtopping in New Orleans during the Katrina Hurri-cane[J].Journal of Geotechnical and Geoenvironmental Engineer-ing,2008,134(5):618～632.
[6]黄润秋,王士天,张倬元,刘汉超.中国西南地壳浅表层动力学过程及其工程环境效应分析[M].四川大学出版社,2001.Huang Runqiu,Wang Shitian,Zhang Zhuoyuan,Liu Hanchao.The dynamic process of earth’s superficial crust and its engineer-ing environmental effects.Sichuan University Press,2001.
[7]谢和平,邓建辉,等.汶川大地震灾害与灾后重建的岩土工程问题[J].岩石力学与工程学报,2008,27(9):1781～1791.Xie Heping,et al..Wenchuan Large earthquake and post-earth-quake reconstruction-related geotechnical problems.Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781～1791.
[8]http://www.cnqc.gov.cn/oa/dhkdzyz.nsf/maindir[EB/OL].(2008-12-1).
[9]任馨,党永平.青川县堰塞湖应急排险施工组织及管理[J].水利水电技术,2008,39(8):27～30.Ren Xin,Dang Yongping.Construction organization and construc-tion management for emergency risk-elimination of landslide dams in Qingchuan County.Water Resources and Hydropower Engineer-ing,2008,39(8):27～30.
[10]Hanson G J.Surface erodibility of earthen channels at high stresses part II-developing an in situ testing devices[J].Transactions A-merican Society of Agriculture Engineers,1990,33(1):132～137.
[11]Hanson G J,Simon A.Erodibility of cohesive streambeds in the loess area of the Midwestern USA[J].Hydrological Processes,2001,(15):23～38.
[12]Chien N,Wan Z H.Mechanics of sediment transport[M].ASCE Press,Virginia.1999.
[13]Hanson G J.Surface erodibility of earthen channels at high stres-ses part I-open channel testing[J].Transactions American So-ciety of Agriculture Engineers,1990,33(1):127～131.
[14]Simons D B,Senturk F.Sediment transport technology[M].Water Recources Publications,Colorado,1971.
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