Taludes instabilizados por percolações, e correcção visceral das análises correntes e das drenagens estabilizantes significativas
DOI:
https://doi.org/10.14195/2184-8394_100_6Palavras-chave:
Análises, Estabilidade, Taludes, Barragens, Correcções, Resistência, DeformaçõesResumo
Passa-se de relance por menção dos complexos fatores de azares e riscos dominantes naturais erráticos menos previsíveis do que os dos maciços construídos sob controle: relembra-se o princípio básico dos atendimentos mediante a seleção do "universo físico" menos vulnerável, sob domínio da estatística de médias. Exemplifica-se na barragem de terra (de Mello, 1977; Viotti, 1989). No tocante as análises convencionais de instabilizações de taludes, demonstra-se que coincidências históricas e regionais (Bishop, 1952) introduziram um "gene poluidor'' em todos os métodos e programas de computação. Gerados por uma hipótese simplificadora de Terzaghi (1936), prevalecem ao longo de 67 anos com um erro significativo conceitual e numérico, obviamente a favor da segurança, anti-económico. Ressalta-se a sedução preponderante da computação, que desviou os civis-geotécnicos dos entusiasmos pela geotecnia apaixonante de aprimoramento dos fatores razoavelmente controláveis. Incorporam-se correcções conceituais e práticas bem fundadas nos avanços pesquisadores, e no questionamento convencido e convincente dos primórdios, inescapavelmente mais grosseiros, de parâmetros e hipóteses que nos serviram por longo tempo, com grato reconhecimento. Exemplificam-se alguns erros a corrigir de imediato.
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