Un criterio robusto para la medida del margen –coeficiente– de seguridad

Informes de la Construcción (Impact Factor: 0.25). 06/2010; 62(518). DOI: 10.3989/ic.08.045
Source: OAI

ABSTRACT En este trabajo se analizan en primer lugar algunos inconvenientes de los habituales coeficientes parciales de seguridad —factores multiplicadores de las cargas— como medida del alejamiento a las condiciones de colapso en el caso de las estructuras con anisotropías importantes, como son especialmente aquellas sin resistencia a la tracción —los arcos de fábrica, como ejemplo paradigmático— Para superar dichas dificultades se propone un criterio sencillo y robusto basado en la contracción de la superficie límite, criterio que aporta una medida coincidente con la habitual para los casos isótropos, pero que permite medir igualmente de forma consistente el alejamiento a las condiciones del colapso para el resto de las situaciones. Se aplica finalmente el modelo a la determinación de los márgenes de seguridad en secciones de doble simetría sometidas a compresión esviada para materiales sin, y con resistencia a tracción, así como al problema de la estabilidad de un prisma frente al vuelco, mostrando las mejoras que aporta para caracterizar dichos problemas.

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