<p>Flysch formations are generally characterised by evident heterogeneity in the presence of low strength and tectonically disturbed structures. The complexity of these geological materials demands a more specialized geoengineering characterisation. <br />In ...

<p>The paper presents geological and engineering geological characteristics of the Strazˇina Tunnel along the Bisko-&Scaron;estanovac section of the Zagreb-Split-Dubrovnik highway in Croatia. This paper compares the actual conditions of the rock mass during ...

<p>The squeezing of tunnels is a common phenomenon in poor rock masses under high in situ stress conditions. The critical strain parameter is an indicator that allows the degree of squeezing potential to be quantified. It is defined as the strain level on ...

The role of classification in rock engineering and design is discussed. It is important to distinguish between characterization, classification and empirical design method. The classification systems used today should, strictly speaking, either be described ...

The history of stress around a circular tunnel during excavation in a homogeneous, isotropic, linear elastic or plastic medium with a strain softening behavior, subjected to either isotropic (Ko = 1) or anisotropic (Ko = 2) state of stress, in 3D conditions ...

A review of underground openings, excavated in varying rock mass types and conditions, indicates that the initiation of brittle failure occurs when the damage index, Di , expressed as the ratio of the maximum tangential boundary stress to the laboratory unconfined ...

Interaction between the ground and the support is well understood and considerable experience has been built up with different construction methods in recent years, the prediction of ground response to tunnelling under squeezing conditions still remains one ...

In this paper, the shape and size of the plastic zone around an underground excavation are predicted using three different approaches: the convergence-confinement method, a continuum numerical approach and a discontinuum numerical model. The results show that ...