Instability of Rockfill Slopes
II Lição Manuel Rocha, 1985
DOI:
https://doi.org/10.14195/2184-8394_47_1Abstract
It is postulated that for improved assessment of static slope stability of rockfills one must consider no only the curved strength envelope, but also the benefits of precompression (analogous to clay preconsolidation) in clean angular rockfills. Moreover, quite low nominal values of computed Factors of Safety F should be acceptable whenever a Factor of Guarantee (FG) is at stake in lieu of the conventional F concept and value. Such concepts are presently referred to simple, conventional, average factors, with which practising professionals are conversant, although one obviously foresees that future steps will lead to probabilistic formulations. For compacted rockfill behavior under seismic shaking it would follow that precompressions by heavy vibratory compaction should significantly improve presented predictions, and, for design purposes, in substitution for further efforts at laboratory and analytical developments, a more profitable result should ensue from appropríate adjustments of compaction energies to cover superabundantly the grossly unpredictable levels of earthquake shaking energies and stresses.
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