The stability of the excavation face of shallow tunnels excavated in difficult ground conditions is currently a relevant problem in the sector for tunnelling and mining. Even though face-reinforcement interventions with fibreglass dowels have proved to be ...

This communication deals with the effect of tunnel face reinforcement on the wall convergence and on the loads in the lining, studied by means of a homogenized anisotropic model for reinforced ground. While the tunneling process is generally handled in a plane ...

<p>Falls of Ground is one of the highest causes of incidents, accidents and fatal injuries in our mines today. <br />These falls of ground may occur as soon as the face is exposed after blasting or after machine cutting. The falls of ground can also occur ...

<p>Pipe Roof Support systems are increasingly being used in weak ground tunneling although the design is often only based on experience. The results of an intensive measurement campaign, including settlement measurements ahead of the face, were used to determine ...

<p>Nowadays a number of tunnels are constructed in urban areas in weak rocks with high or low overburden. In both cases geodetic methods are used to monitor displacements and control stability. In special cases additional other measurement systems are used ...

<p>Tunnels of 10 to 16 m span are frequently constructed for hydroelectric or transportation projects, and many of these tunnels are excavated in rock masses of very poor quality. When the ratio of rock mass strength to in situ stress falls below 0.2, squeezing ...

<p>The paper describes the design considerations and the experiences from the<br />construction of two shallow motorway tunnels in Greece. The ground consists of stiff clays, clayey sands and silts. The hydrogeological conditions are complex.<br />The tunnels ...