摘要
宁夏某工程输水线路全长75.29 km,7^#隧洞长10593 m,为本工程单洞最长、埋深最大、地质条件相对复杂的洞段。围岩岩性主要为泥岩,岩体较为破碎,主要以Ⅳ、Ⅴ类围岩为主,其中Ⅳ类围岩所占比例为86.21%。隧洞区地下水类型主要为孔隙潜水和基岩裂隙水隧洞,外水水头130~240 m,存在高外水问题。隧洞断面较小,二次衬砌采用外标准马蹄形、内平底马蹄形的复合断面形式。综合考虑结构受力、排水措施的影响,对断面进行了合理简化,高外水折减系数进行适当调整,并采用理正岩土隧洞衬砌计算软件程序进行结构分析,提出Ⅳ类围岩最终的建议配筋结果,取得了较为理想的效果。
A project in Ningxia is 75.29 km long.No.7 tunnel is 10593 m,it is a section with longest single tunnel,largest buried depth and complex geological conditions.The surrounding rock is mainly mudstone,and the rock mass is relatively broken,mainly composed of type IV and V rocks,of which type IV rock accounts for 86.21%.The groundwater in the tunnel area is main pore phreatic water and bedrock fissure water with the external water head of 130-240 m,high external water problem is existed.The section of No.7 tunnel is small,and the secondary lining adopts compound form of standard horseshoe shape outside and flat bottom horseshoe shape inside.Considering the influence of structural stress and drainage measures,the section is reasonably simplified in the design,and the high external water reduction coefficient is adjusted,Lizheng geotechnical tunnel lining calculation software is used for structural analysis,and the final recommended reinforcement results of type IV rock is obtained,which gets a relatively ideal effect.
作者
常峻
杨凡
Chang Jun;Yang Fan(China Water Resources Beifang Investigation,Design and Research Co.Ltd.,Tianjin,300222)
出处
《水利水电工程设计》
2020年第2期6-8,56,共4页
Design of Water Resources & Hydroelectric Engineering
关键词
隧洞衬砌
Ⅳ类围岩
泥岩
高外水
理正岩土
配筋计算
tunnel lining
type Ⅳ rock
mudstone
high external water
Lizheng geotechnical
reinforcement calculation
