INTRODUCTION Estimating groundwater inflow into a tunnel before and during the excavation process is an important task to ensure the safety and schedule during the underground construction process. CASE DESCRIPTION Here we report a case of the forecasting and prevention of water inrush at the Jinping II Hydropower Station diversion tunnel groups during the excavation process. The diversion tu...

In this paper by using numerical evaluation the effect of balancing drupes of water hammer on tunnels lining is considered. In case of not arrangment of these reservoirs, the tunnel lining will be damaged of cyclic powers of water hammer. In this research, function of balancing reservoir of water hammer on cover of tunnels to the barriers’ turbine is simulated by numerical methods and Plaxis 3D...

Abstract— According to the rules of quantum mechanics there is a non-vanishing probability of for an electron to tunnel through a thin insulating barrier or a thin capacitor which is not possible according to the laws of classical physics. Tunneling of electron through a thin insulating barrier or tunnel junction is a random event and the magnitude of current flowing due to the tunneling of ele...

The lining structure of Tunnel Boring Machine (TBM) excavated tunnels is composed of series of precast Reinforced Concrete (RC) pieces which are called segment. At the present paper, a novel method is introduced for seismic retrofitting of segmental tunnels located at active fault zones in rock environment with case study of Amirkabir dam to Tehran water transfer tunnel (Karadj tunnel). The mai...

The low atmospheric pressure and low oxygen content in high-altitude environment have great impacts on the functions of human body. Especially for the personnel engaged in complicated physical labor such as tunnel construction, high altitude can cause a series of adverse physiological reactions, which may result in multiple high-altitude diseases and even death in severe cases. Artificial oxyge...

An existing open circuit wind tunnel has been modified to incorporate a secondary supply loop to provide controlled flow conditions at the inlet to a film cooling hole model. The primary or crossflow fluid enters from atmosphere through a smooth two dimensional contraction before entering the working section. The newly constructed supply loop has a single inlet from a high pressure source, in-l...

surface-piercing propellers (spps) have been widely used in high speed craft due to some desirable features such as high efficiency, omission of resistance of equipment attached to the propeller and proper functioning of cavitation. unlike the submerged propellers, theoretical methods have no significant application on simulation of sppsbecause of problems related to modeling of these propeller...

the hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced concrete, which is an interaction problem between water, soil or rock and concrete lining. although reinforcing the concrete lini...

The 10.6 km long Sabzkuh water conveyance tunnel is currently under construction in High Zagros structural zone, located in western Iran, has used conventional (in section T1) and mechanized (in section T2) methods. The section T1 of the tunnel driven through alluvial geological units with great complexity in an area high potential for sliding and water-bearing fault which has made the excavati...

qomroud water conveyance tunnel (lot 1&2) with the length of 16 kilometers is considered as one of the greatest development and national projects in iran. since about 2 kilometers of tunnel pass through alluvium and the rest of the tunnel pass through various types of geological units, and due to the complexity of geological condition and variety of effective criteria, suitable selection of...