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Ensayo de Placa Para la Evaluación de la Tenacidad del Hormigón Proyectado Con Fibras: Revisión Crítica de las Técnicas de Ensayo

CURSO 01/2006;

ABSTRACT Resumen: En muchas de las aplicaciones del hormigón en los campos de ingeniería se requieren ciertas propiedades que este material como tal no ofrece. Los avances más recientes sobre la materia nos llevan al hormigón reforzado con fibras. Dicho refuerzo aumenta notablemente la capacidad de absorción de energía y permite una mejor distribución de tensiones sobre el material. Para cuantificar las mejoras del comportamiento mecánico que aporta este refuerzo no se hace en base a la resistencia sino que debe analizarse el proceso postpico y ver el incremento de tenacidad respecto al hormigón en ausencia de este. Para la medida de la tenacidad existen varios ensayos correspondientes a diferentes normativas. En este artículo se analizarán los procedimientos para la evaluación de este parámetro en placas de hormigón y se hará una revisión crítica sobre las dificultades de su ejecución y de la fiabilidad de los resultados obtenidos. Palabras clave: hormigón proyectado, fibras, ensayos de placa, tenacidad.

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