双江口电站高地应力区地下厂房系统第Ⅰ层开挖岩爆发育规律和岩爆预测初步研究  

Preliminary study on rockburst development law and rockburst prediction in excavation of layer Ⅰ of underground powerhouse system in high geostress area of Shuangjiangkou hydropower station

作　　者：马行东 黎昌有 王修华 袁国庆 马宏 MA Xingdong;LI Changyou;WANG Xiuhua;YUAN Guoqing;MA Hong(PowerChina Chengdu Engineering Corporation Limited,Chengdu,Sichuan 610072,China)

机构地区：[1]中国电建集团成都勘测设计研究院有限公司,四川成都610072

出　　处：《岩石力学与工程学报》2020年第S01期2964-2972,共9页Chinese Journal of Rock Mechanics and Engineering

摘　　要：双江口电站左岸实测最大主应力37.82 MPa、NNW向,是在建和已建国内水电站地下厂房系统最高实测地应力,属高~极高地应力区。开挖揭示,左岸洞室群岩爆现象极其普遍和突出,主要表现为第Ⅰ层开挖岩爆现象凸显、全断面且连续发育、发育面积大、"V"型爆坑明显、浅表部0.2~0.5 m薄层状环断面片帮剥离,开挖初期岩爆现象突出、有一定滞后效应、持续时间长,具有典型的时间和空间效应。统计规律表明,岩爆破坏类型以应力型岩爆为主,局部发育构造型岩爆;第Ⅰ层岩爆等级轻微~中等;岩爆支护时机宜2~3 d等。根据第Ⅰ层岩爆发育规律,开展了岩爆破坏类型、岩爆等级、岩爆时空特征、岩爆破坏现象等的岩爆预测初步研究,以期通过下卧开挖对比,总结岩爆预测经验,对其他工程岩爆预测有一定的借鉴。The measured maximum principal stress on the left bank of Shuangjiangkou Hydropower Station is 37.82 MPa,NNW direction,which is the highest measured ground stress of the underground powerhouse system of the domestic hydropower station under construction and under construction,belonging to the high to extremely high stress area.The excavation reveals that the rockburst phenomenon of the left bank cavern group is extremely common and prominent,which is mainly manifested in the prominent rockburst phenomenon of the first layer excavation,the continuous development of the whole section,the large development area,“V”type blasting pit is obvious,the shallow surface 0.2-0.5 m thin-layer circular section is stripped,the rockburst phenomenon is prominent at the initial stage of excavation,with a certain lag effect and a long duration,with typical time and space effect.The statistical law shows that the failure type of rockburst is mainly stress rockburst,with structural rockburst locally developed;the rockburst level of the first layer is slight to medium;the time of rockburst support is suitable for 2 to 3 days.According to the law of rockburst development in the first layer,the preliminary study on rockburst prediction is carried out,such as rockburst failure type,rockburst grade,rockburst time-space characteristics,rockburst failure phenomenon,etc.,in order to summarize the experience of rockburst prediction through the comparison of underground excavation,and provide some reference for other engineering rockburst prediction.

关 键 词：水利工程 岩爆预测 高地应力 地下厂房系统 双江口电站 

分 类 号：TV31[水利工程—水工结构工程]