电力隧道近距离底穿输水方涵应力变形分析  

Analysis of Stress and Deformation for Short Distance Bottom Crossing Water Conveyance Culvert

作　　者：刘光华[1] 魏红[1] LIU Guanghua;WEI Hong(Beijing Institute of Water,Beijing 100048,China)

机构地区：[1]北京市水利规划设计研究院,北京100048

出　　处：《人民黄河》2020年第4期108-111,共4页Yellow River

摘　　要：目前关于穿越大型具有防渗要求的输水结构的分析研究相对较少。采用三维数值模拟仿真技术,对穿越南水北调中线北京段卢沟桥输水暗涵(方涵)电力隧道竖井、掘进施工过程及其引发输水方涵结构应力应变、变形响应进行了动态模拟。通过应力应变分析及关键点的沉降监测追踪得出,该电力隧道施工造成在输水方涵顶部结构产生拉应力,约为0.36 MPa,引发输水方涵最大沉降达到2.86 mm,发生在方涵靠近竖井侧,接近于输水方涵极限沉降值3.0 mm,临近输水方涵的竖井开挖使输水方涵结构产生的不均匀沉降值达到了1.3 mm,会对输水方涵的结构产生不利影响。隧道穿越地层为卵石松散层,掘进开挖步距不宜大于0.5 m,对电力隧道周围土体需进行注浆加固处理,施工应遵循“管超前、严注浆、勤量测、短开挖、强支护、快封闭”的原则。There are many analysis and researches on the crossing engineering of urban engineering construction and relatively few water con veyance structures with impervious requirements for crossing large scale projects.In this paper,three dimensional numerical simulation tech nology was used to dynamically simulate the construction process of electric tunnel shaft and tunneling,and its response to stress,strain and deformation of culvert structure.Through stress strain analysis and settlement monitoring tracking of key points,the tensile stress of the top structure of the culvert is about 0.36 MPa,but the maximum settlement of the culvert is 2.86 mm,which occurs near the shaft side of the cul vert,approaching the limit settlement of the culvert 3.0 mm and near the shaft of the culvert.The excavation has a great influence to the une ven settlement of the culvert itself.The uneven settlement value of the culvert structure reaches 1.3 mm,which will have a negative impact on the structure of the culvert.It is proposed that the tunnel passes through the stratum with pebble loose layer,and the excavation distance should not exceed 0.5 m.Soil around the power tunnel should be reinforced by grouting.Pipe advance,strict grouting,frequent measure ment,short excavation,strong support and quick closure should be adopted in construction.

关 键 词：隧洞 输水方涵 数值模拟 应力变形 防渗 南水北调工程 

分 类 号：TV68[水利工程—水利水电工程]