Seismic bearing capacity of shallow foundations near rock slopes using the generalized Hoek–Brown criterion

Abstract

International audienceThe seismic bearing capacity of shallow foundations resting on a modified Hoek–Brown rock mass is investigated within the framework of the kinematic approach of limit analysis theory. The analysis focuses on evaluating the reduction in bearing capacity induced by seismic loading and by the proximity of a rock slope. A pseudo-static approach is adopted to account for the earthquake effects for the seismic bearing capacity evaluations. At the rock material level, the closed-form expressions previously obtained for the support functions of the rock failure criterion allow the implementation of different failure mechanisms families, and thus to derive rigorous upper bounds estimates of the load-bearing capacity in both static and seismic conditions. The effects of geometrical, strength and loading parameters are assessed through a large number of parametric computations. Finally, design tables are presented for practical use in rock engineering

Seismic stability analysis of rock slopes by yield design theory using the generalized Hoek-Brown criterion

“…Several methods are available to perform this type of study; the simplest is the pseudo-static method. This approach is widely accepted as a means to assess the seismic slope stability [22][23][24][25]. To simulate the potential inertia forces due to ground accelerations in an earthquake, horizontal and vertical static seismic forces are introduced.…”

“…Only the coefficient K h is taken into account, the coefficient K v is neglected. This hypothesis has been adopted by several researchers [22][23][24][25]. What distinguishes this work is the direct use, in calculations, of the Hoek-Brown failure criterion.…”

Displacement-based seismic design of a shallow strip footing positioned near the edge of a rock slope

“…More recently, the modified HB criterion has been also used to evaluate the seismic bearing capacity of strip foundations on rock slopes with two different approaches [19,20]. Yang [19] used the generalized tangential technique in which the modified Hoek-Brown strength is replaced by an "optimal" tangential Mohr-Coulomb domain in a limit analysis framework where the upper-bound solutions are obtained by optimization.…”

“…In this work, the footing is located on the edge of the slope. In [20], the modified HB criterion was implemented in its original form also within the framework of the kinematic approach of limit analysis theory and considering several failure mechanisms. In both works mentioned above the seismic analysis is conducted adopting the conventional pseudo-static approach where the earthquake effects are represented in an approximate manner by constant and static forces acting only in the horizontal direction.…”

Analysis of the seismic bearing capacity of shallow foundations

“…It has allowed obtaining a series of upper envelopes of the exact solution and thus establishing a comparison between the different existing theories. Moreover, during last years the problem of seismic bearing capacity of foundations on slopes or near to them has received attention (Choudhury & Subba Rao, 2006;Yang, 2009;Castelli & Motta 2010;Saada et al, 2011;Farzaneh et al, 2013). However, it has to be mentioned that, although the solutions obtained by using the upper bound theorem of limit analysis theory are rigorous ones and allows limiting the exact solution, they correspond, in general, to an unsafe estimate of the failure load.…”