泸定6.8级地震大岗山拱坝微震损伤演化与风险区域识别  

MICROSEISMIC DAMAGE EVOLUTION AND IDENTIFICATION OF RISK AREAS OF THE DAGANGSHAN ARCH DAM IN LUDING 6.8 EARTHQUAKE

作　　者：马克 王龙江[1,2] 唐春安 黄会宝[3,4] 高志良 沈定斌 MA Ke;WANG Longjiang;TANG Chun'an;HUANG Huibao;GAO Zhiliang;SHEN Dingbin(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China;Institute of Rock Instability and Seismicity Research,Dalian University of Technology,Dalian 116024,China;CHN Energy Dadu River Hydropower Development Co.,Ltd.,Chengdu 610041,China;College of Water Resource and Hydropower,Sichuan University,Chengdu 610065,China)

机构地区：[1]大连理工大学,海岸和近海工程国家重点实验室,大连116024 [2]大连理工大学,岩石破裂与失稳研究中心,大连116024 [3]国能大渡河流域水电开发有限公司,成都610041 [4]四川大学,水利水电学院,成都610065

出　　处：《工程地质学报》2025年第1期146-158,共13页Journal of Engineering Geology

基　　金：国家自然科学基金面上项目(资助号:51974055).

摘　　要：大岗山拱坝在2022年9月5日泸定6.8级地震及其余震发生时,发生强烈震动。为研究大岗山拱坝在此次地震作用下的内部损伤情况及震后安全稳定性,利用大岗山拱坝微震监测系统,首次对拱坝在地震作用下的微破裂现象进行了有效监测。在此基础上探究了地震影响下的坝体微震事件演化过程及成因,提出了大岗山拱坝在地震作用下的风险区域,并对震后拱坝安全稳定性进行了评价。研究表明:大岗山拱坝微震事件的激增与地震扰动存在密切关联。地震前拱坝微震活动性较弱,微震事件数量较少。地震发生及震后,较强的外部地震扰动,使拱坝发生持续的位移变形,并发生应力调整,从而诱发大量微震事件的发生,最高单日微震事件数量高达231个。微震事件空间分布和微震变形主要影响区域揭示了拱坝的风险区域是以拱冠梁所在坝段为中心的5^(#)~6^(#)、10^(#)~11^(#)、13^(#)~16^(#)及19^(#)~20^(#)坝段的中上部区域。在震后一段时间内,坝体微震事件数量逐渐减少,微震视体积及能量释放情况能够恢复到震前水平。地震作用下坝体微震事件未扩展形成明显的宏观裂缝,且坝体未见损伤,大岗山拱坝在经历地震扰动后仍是安全稳定的。The Dagangshan arch dam was strongly shaken when the Luding 6.8 magnitude earthquake and its aftershocks occurred on 5 September 2022.In order to study the internal damage and post-earthquake safety stability of the Dagangshan arch dam under the action of this earthquake,the microseismic monitoring system of the Dagangshan arch dam was used to effectively monitor the microfracture phenomenon of the arch dam under the action of the earthquake for the first time.On this basis,the evolution process and causes of dam microseismic events under the influence of the earthquake were explored,the risk area of the Dagangshan arch dam under the action of earthquakes was proposed,and the safety and stability of the arch dam were evaluated after the earthquake.The results show that the surge of microseismic events at the Dagangshan arch dam is closely associated with seismic disturbances.Microseismic activity in the arch dam is weak before the earthquake,and the number of microseismic events is low.During and after the earthquake,stronger external seismic disturbances cause continuous displacement and deformation of the arch dam,resulting in stress adjustments in the dam body,which induces a large number of microseismic events,and the maximum number of microseismic events in a single day is as high as 231.The spatial distribution of microseismic events and the main impact areas of microseismic deformation reveal that the risk areas of the arch dam are the middle and upper areas of dam sections 5^(#)~6^(#),10^(#)~11^(#),13^(#)~16^(#),and 19^(#)~20^(#),centered on the dam section where the crown cantilever is located.In a period of time after the earthquake,the number of microseismic events in the dam decreases gradually,and the microseismic apparent volume and energy release of microseismic events are able to return to the pre-earthquake level.The microseismic events of the dam do not expand to form obvious macroscopic cracks,and no damage is found in the dam;the Dagangshan arch dam is still safe and stable after the earthquak

关 键 词：拱坝 微震监测 损伤演化 地震作用 

分 类 号：TV642.46[水利工程—水利水电工程]