hoekparameters

Hoek parameters, also known as Hoek-Brown parameters, are a set of empirical constants used in the Hoek-Brown failure criterion. This criterion is a widely used model in rock mechanics to predict the strength of rock masses, particularly in situations involving discontinuities like joints and faults. The criterion relates the shear strength of a rock mass to the unconfined compressive strength of its intact rock and the characteristics of the discontinuities present.

The primary Hoek parameters are 'm' and 's'. The parameter 'm', often denoted as m_i, represents the Hoek-Brown constant for intact rock. It quantifies the influence of the material's microstructure and mineralogy on its strength. The parameter 's' is a factor that accounts for the degree of disturbance or weathering of the rock mass. A perfectly undisturbed, intact rock mass would have s = 1, while heavily fractured or weathered rock masses have s values approaching zero.

As the Hoek-Brown criterion is extended to rock masses, two additional parameters are introduced: 'GSI' (Geological Strength Index) and 'D' (Disturbance factor). The GSI is a qualitative index assigned based on the visual appearance of the rock mass, considering factors like joint spacing, joint condition, and blockiness. The disturbance factor 'D' quantifies the extent of damage to the rock mass, such as from blasting or geological processes. These parameters are then used to modify the intact rock strength to predict the overall strength of the rock mass. The Hoek parameters are crucial for engineering applications such as tunnel design, slope stability analysis, and underground excavation.