A closed-form analytical solution to rheological phenomena is obtained based on Hoek-Brown (HB) yield criterion and the generalized Bingham model. Once circular tunnel excavated, an initial plastic region formed. When total stresses fulfil condition, steps into viscoplastic region, in which displacement develops with time. The one-dimensional constitutive equation of model transformed a three-d...

Brown algae, the Phaeophyceae (or Fucophyceae; Christensen, 1978), are a class (or division, Phaeophyta; Papenfuss, 1951) of algae consisting mainly of complex, macroscopic seaweeds whose brown color comes from a carotenoid pigment, fucoxanthin, and in some species, various phaeophycean tannins. Of perhaps 2000 species (in 265 genera) of brown algae (Van den Hoek et al., 1995), less than 1% are...

A series of uniaxial and triaxial compression tests were performed on slate samples with different diameters at foliation orientations respect to the direction major principal stress. The size effect anisotropy in slate, as a transversely isotropic rock, investigated, research focused aspects elastic properties, compressive strength (UCS), (TCS), residual (TRS). In five constants for only Young...

Abstract Accurate description of the failure strength behaviors rock materials, including intact rocks and jointed masses, is essential for engineering design construction. First, a novel three-dimensional (3D) version Hoek–Brown (HB) criterion proposed in this paper. A stress weighting factor n used to describe effects intermediate minimum principal stresses. The 3D validated using six sets po...

Some of the geotechnical parameters used in the analysis may not be accurately measured directly from laboratory tests due to effects of sample disturbance and errors of tests. The back analysis or the observational method are thus often applied to determine the representative and/or dominant strength parameters based on field observations in practice. Based on the Hoek-Brown failure criterion,...

Strength properties of most sedimentary and metamorphic rocks are known to vary with direction. Knowledge this so-called rock anisotropy is utmost importance for reliability analysis engineering design. The purpose paper twofold. First, we propose a formulation the Hoek–Brown (HB) failure criterion, which calculates strength using non-uniform scaling stress tensor. We use two factors, CN CS, li...