No abstract

No abstract

Reliable reduction factors for timber mechanical properties at elevated temperatures are needed to design timber structures for fire safety as well as to assess the safety of historic timber structures against fire hazards. In this paper, a compilation of the available data on the compressive and tensile strengths of timber at elevated temperatures is carried out. Then, a probabilistic modeling approach to predict the temperature-dependent reduction factors applicable to fire design is proposed. The collected data cover both solid and engineered timber at temperatures from 20°C to 300°C, with a variety of sample sizes, wood species, test protocols, and moisture content used in the experiments. The data revealed a large scatter in elevated temperature strengths, and a large conservativeness of the relationships of the current European standard, which is commonly used for the advanced design of timber structures under fire. To address this variability, multiple probability density functions were calibrated across the temperature range, quantifying the goodness of fit with statistical criteria. Two-parameter Weibull functions provided the best fit, and continuous temperature-dependent relationships were derived for the parameters of the distribution. The proposed probabilistic models can be implemented in a numerical code, facilitating their use in analytical and computational approaches, and can be applied to the probabilistic assessment of the structural performance and reliability of timber structures against fire.

La evolución de la sociedad requiere de un importante número de profesionales con formación técnica, lo que impulsa que las universidades tecnológicas desarrollen programas para despertar vocaciones. Este artículo presenta un taller desarrollado en la Universitat Politècnica de València con la finalidad de acercar la ingeniería civil y estructural a los estudiantes de secundaria y que vean estas disciplinas como algo atractivo y creativo. Para ello, se organiza un concurso en el que equipos de estudiantes construyen puentes a escala reducida con una cantidad limitada de espaguetis y los llevan hasta la rotura, ganando el equipo cuyo puente aguante la mayor carga con la menor cantidad posible de espaguetis. El artículo proporciona los detalles de la experiencia y evidencias cualitativas de su éxito. La experiencia es económica y sencilla de realizar, por lo que es fácilmente extrapolable a otros entornos educativos.