摘要
川江流域历史地震是影响川江流域沙量与河床演变的主要动力因素之一,汶川地震是龙门山断裂带有历史文献记录以来发生的最大地震灾害。通过历史资料收集、野外调查与理论分析相结合,探讨了汶川地震后多种自然因素与人类活动对龙门山山前河流演变的影响,揭示了强震受损山前河流河床演变规律,提出了变化环境下的山前河流河床演变模式及其预测方法。结果表明:汶川地震后龙门山山前河流均发生了不同程度的下切,尤以石亭江为甚,2015年汛后在105省道处最大下切深度达到27.0 m;震后山前河流剧烈下切的影响因素众多,且各种影响因素相互影响、相互混掺,"来水来沙条件突变、比降不和谐"是主要内因,"工程阻隔、无序采砂"是主要外因;基于"河流临界起动假说河相关系"建立的变化环境下山前河流河床演变模式及其预测方法适用性较好,可供类似强震受损山前河流参考。
The historical earthquakes in Chuanjiang catchment were one of main dynamic factors which affect the local sediment yield and fluvial processes. The Wenchuan earthquake is the largest earthquake in the recorded history of the Longmenshan fault. Through historical data collection, field study and theoretical analysis, the effects of various natural factors and human activities on the fluvial i processes of the piedmont rivers in Longmen Mountains are explored, and the evolution rules of piedmont rivers damaged by strong earthquakes are revealed, and the piedmont river evolution model and its prediction under the changing environment are proposed. The results show that： after the earthquake, different levels of evolutions of piedmont rivers have taken place in the Longmen Moun- tains, especially in the Shiting River, with the maximum downcutting depth of 27.0 m at the 105 Provincial Highway after the flood season of 2015; there are many factors affecting the dramatic evolution of piedmont rivers in Longmen Mountains after the earth- quake and those factors are mixed and interacted with each other. While ＂water and sediment supply mutation and dissonance slope＇ are the main internal causes, ＂engineering barriers and disorder sand mining＂ are the main external causes. The piedmont river evolu- tion model and its prediction established by the ＂hydraulic geometry based on the river critical initiation hypothesis＂ have good ap- plicability and can be used as reference for analyzing the similar strong earthquake-damaged piedmont rivers.
作者
聂锐华
王小凡
刘发明
王强
范念念
刘兴年
NIE Ruihua;WANG Xiaofan;LIU Faming;WANG Qiang;FAN Nianntan;LIU Xingntan(State Key Lab. of Hydraulics and Mountain River Eng., Siehuan Univ., Chengdu 610065, China;College of Water Resource and Hydropower, Siehuan Univ., Chengdu 610065, China;China Railway Eryuan Eng. Group Co. Ltd., Chengdu 610031, China)
出处
《工程科学与技术》
EI
CAS
CSCD
北大核心
2018年第3期105-111,共7页
Advanced Engineering Sciences
基金
国家重点研发计划资助项目(2016YFC0402302)
国家自然科学基金资助项目(51779163
51509172)
关键词
汶川地震
山前河流
演变模式
水沙条件
比降不和谐
Wenchuan earthquake
piedmont rivers
processes pattern
runoff-sediment condition
dissonance slope
