Structural Analysis Of Tunnel Lining For Deep Buried Low-Pressure Hydraulic Tunnels

As the increase of the hydroelectric development in our country, the buried depth of hydraulic tunnel is more and more. Although the satisfied result has been acquired in study of structural analysis lining and stress analysis of surrounding rock in deep buried high-pressure hydraulic tunnel by using finite element method, impercipient analysis of disadvantageous factor by external water pressure in deep buried low-pressure hydraulic tunnel exist in mini-hydropower station, as the tunnel's internal water pressure is less, especially when tunnel endure low head.In this paper, the author in accordance with impercipient analysis of disadvantageous factor by external water pressure when carry out Structural Analysis of Tunnel lining for Deep Buried low-pressure hydraulic tunnels in mini-hydropower station, the method of bound & finite element (plane elastoplastic finite element of non-linear finite element method)to be recommend in Specification for design of hydraulic tunnel is used . The study consists of the surrounding rock's stability and structural analysis of concrete tunnel lining and the engineering measure need to be do to be carried out for horseshoe-shape hydraulic tunnels in Qinggangxia station of Datonghe River in Qinghai province. The study of deformation analysis of (non-consolidation grouting comparing to consolidation grouting to finished) in tunnel and in fault plane to been done.In accordance with the analysis of the method of bound & finite element, acquire the result: since the deep buried low-pressure hydraulic tunnel is buried very deep , the tunnel endure more external water pressure. The plastic deformation of surrounding rock is obvious, so the tunnel lining's internal force to be controlled by external water pressure, need to carrying out measure to be reduce external water pressure, the stress of tunnel lining should be monitor in typical section when the drainage is done comparing to when the drainage is not done. The deformation of surrounding rock influenced by consolidation grouting is very small, but the internal force of tunnel lining influenced by consolidation grouting is obvious when tunnel lining's...