The use of fiber reinforced concrete with wet sprayed concrete technique can improve the concrete lining structure construction quality and improve the rock mass self-bearing capacity. In the paper, the introduction of the wet-sprayed fiber reinforced concrete is proposed to be the ideal tunnel lining structure in both the hard rockmass and the soft and weak rockmass, namely Dongjusigou railway tunnel and Jinhuashan railway tunnel early stage lining structure. The monitoring data result shows that the rock mass pressure in experimental section is even distribution with lower rock mass pressure and lower concrete lining layer stress. The value of rock mass pressure and tunnel lining layer stress in comparison tunnel section is a little higher than that in experimental tunnel section. The experimental tunnel section using fiber reinforced concrete has good lining effect.
The main idea of the New Austrian Tunnel Method is to utilize the self-bearing capacity of the rock, which has been widely applied in the field of the highway, railway tunnel engineering and underground engineering. The tunnel lining structure using both the anchor bolt and the wet-sprayed concrete is the modern underground engineering lining structure with the application of the New Austrian Tunnel Method, which has been successfully used in the field of the mining, building, railway, military engineering. The railway tunnel design code of China (TB10003–2001) [1] stipulates that the lining structure for tunnel must be done and the lining structure using both the anchor bolts and the wet-sprayed concrete is suggested. The anchor bolt and the wet-sprayed concrete lining structure is a flexible lining structure, which can utilize the self-bearing capacity of the rock around. Recently the fiber reinforced concrete is applied in the tunnel lining structure, such as the steel fiber reinforced concrete, the non-steel fiber reinforced concrete, the hybrid fiber reinforced concrete, the polypropylene fiber reinforced concrete. The polypropylene reinforced concrete has higher compressive strength, tensile strength, flexural strength, anti-impact strength compared with other fiber reinforced concrete, which can reduce the thickness of the tunnel lining structure [2]. There remains no design code on the tunnel lining structure using the anchor bolt and the wetsprayed polypropylene fiber reinforced concrete. It is necessary to grasp the deformation and the force distribution process of the tunnel lining construction process using the anchor bolt and the wet-sprayed polypropylene fiber reinforced concrete to construct such tunnel lining structure. The wet-sprayed fiber reinforced concrete is first introduced in the railway tunnel lining construction in China. It is difficult to design such lining structure according to the existing tunnel design codes. In order to investigate the nonlinear deformation and the internal force distribution of such lining structure to assure the structure safety, the nonlinear finite element method is carried out to investigate the wet-sprayed fiber reinforced concrete lining construction process. In the paper, the nonlinear finite element analysis using ADINA [3] is performed to model the railway tunnel construction process. The nonlinear deformation characteristic and the stress field, the plastic zone distribution is studied using the numerical method. The deformation and the plastic zone comparison is made between using the wet-sprayed polypropylene fiber reinforced concrete lining structure, the wet-sprayed common concrete lining structure, no lining structure.
