Slopes instabilised by percolation, and visceral correction of current analysis and significant stabilising drains
DOI:
https://doi.org/10.14195/2184-8394_100_6Keywords:
Análises, Estabilidade, Taludes, Barragens, Correcções, Resistência, DeformaçõesAbstract
Mentioning in passing Nature's complex factors of dominant hazards and risks, erratic, much less predictable than those of soil structures built under control, one recalls the basic principle of solving challenges by change of "physical universe" to a less vulnerable one, amenable to the statistics of averages. It is exemplified with an earth dam (de Mello, 1977; Viotti, 1989). Moving to conventional analyses of slope destabilizations, one demonstrates that historic and regional coincidences (Bishop, 1952) introduced a "polluting gene" into all the methods and computer programs in use. Generated by a simplifying assumption of Terzaghi (1936) the calculations persist along 67 years with an appreciable error, conceptual and numerical, obviously conservative, uneconomical. One senses a predominant seduction of computation, diverting the civil-geotechnicians from enthusiasms towards the exhilaration of progressive advancement of geotechnique's really controllable factors. One submits proposed conceptual and practical corrections, founded on the questful advances, and on convinced and convincing querying of the primordial steps, inevitably cruder, of parameters and hypotheses gratefully recognized as having served the profession for a long time. Examples are presented of some of the errors, amenable to prompt corrections.
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