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A variety of engineering activities require reliable evaluation of rock strength. For instance, the stability of rock slopes depends on structural geology of rock massif in which the slope is excavated. Hoek-Brown (HB) failure criterion applied in rock design practice introduces factors based on the properties of jointed rock. The non-linear finite element safety calculation is conveniently used for calculation safety the factor of slope stability. The Mohr-Coulomb (MC) failure (strength) criterion for soil is widely applied in geotechnical design. Therefore, the appropriate transformation from HB to the equivalent MC, employing angle of shearing resistance φ and cohesion c, is necessary. This article studies the effect of jointed rock massif properties on the transformed MC parameters by using Sobol’s global sensitivity analysis (SSA) and HB transformation equations. Statistical parameters needed for the evaluation of sensitivity analysis are processed using classical statistical methods upon the emulation of Latin Hypercube Sampling simulation methods. Developed and adapted by authors techniques are illustrated by processing real rock investigation data from survey of the trachyte massif located in the Czech Republic. The first and higher order effects of random inputs are identified using SSA. It is illustrated that the effects of inputs on the MC parameters varies significantly depending on the discontinuity distribution and height of the slope.

The paper presents an application of statistical and numerical methods for the determination of the forcedisplacement curves and that of pullout capacity of prestressed grouted ground anchors installed in Miocene clay. A regression analysis of data from a database of acceptance test records for ground anchors to create has been performed, the force-displacement curve of the tested anchor corresponding to the range of loads applied for acceptance tests has been created. A linear regression model, employing the weighted least squares method and robust standard errors techniques were concluded to serve as a reliable statistical method suitable for achieving this goal. The discovered linear regression dependence then served as a lower control limit for the displacement values calculated at the anchor head applying the numerical model. A finite element model has been created to predict the behaviour of ground anchors being installed in fine-grained soils. The developed numerical model that employs Mohr-Coulomb strength criterion constitutive model evaluates the influence of high-pressure grouting by development additional radial stresses and that of an increment of fixed length diameter.

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