摘要
文家沟于2010年8月13日爆发泥石流,一次下泄量达460万m3,沟床下切深度最大约70 m,是5.12大地震后典型的次生地质灾害,也是我国近年来规模较为罕见的特大型泥石流。鉴于该泥石流规模巨大、地质条件复杂,在治理方案的选择和设计上具有很大难度。在分析该泥石流典型特征、成因以及各功能分区地形特征和坡体物质组成的基础上,详细论证了排导、拦挡、固源、截水分流等措施在该泥石流沟防治工程中的效果和局限性,通过比选和设计,论证了"水石分离"综合治理措施的可行性和治理效果,为大型泥石流治理提供了新的思路。
As the secondary disaster after the megaquake on May 12,2008,a heavy debris flow broke out on August 13,2010 in Wenjiagou village with its one-time discharge amount up to 4.6 million cubic meters and maximum depth of gully bed downcutting over 70 meters.This catastrophic debris flow,together with complex geological conditions,makes it challenging to select and design the control scheme.Based on analysis of the formation and source of the debris flow,we demonstrated the effects and limitations of control schemes involving drainage,obstructing,source consolidation,flow cutoff and diversion.Through comparison,we proposed the scheme of separating the upstream water flow with middle stream stone by flow diversion tunnels.The project consisted of diversion tunnel,catch basin,diversion dike,and screening grids at the bottom of the catch basin.The project was proved to be effective through rainfalls of 165mm,130mm,182.4mm in 2011.This research provides a new approach and could be referential for the control over large-scale debris flow.
引文
[1]DZ/T0220-2006,泥石流灾害防治工程勘查规范[S].(DZ/T0220-2006,Specification of Geological Investiga-tion for Debris Flow Stabilization[S].(in Chinese))
[2]DZ/T0239-2004,泥石流灾害防治工程设计规范[S].(DZ/T0239-2004,Specification of Prevention Engi-neering Designs for Debris Flow[S].(in Chinese))
[3]四川省地质工程集团公司.绵竹市清平乡文家沟“8.13”特大山洪泥石流灾害应急勘查报告[R].成都:四川省地质工程集团公司,2010.(Sichuan GeologicalEngineering Group.Report on the Emergent Investigationfor the 8.13 Catastrophic Debris Flow at Wenjiagou,Qingping town,Mianzhu City[R].Chengdu:Sichuan Ge-ological Engineering Group,2010.(in Chinese))
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