Browsing by Author "Silva, Lino"
Now showing 1 - 5 of 5
Results Per Page
Sort Options
- Fire safety of wood-steel connectionsPublication . Fonseca, Elza M M; Silva, Lino; Leite, Pedro A. S.The main objective of this work is to present different analytical and computational methods which permit the safe design calculation of the wood-steel connections, under fire conditions. Wood is an anisotropic, heterogeneous and porous material and its behaviour varies with temperature. The increase of temperature influences the progressive degradation of wood properties. During fire exposure, it is need to determine if the charred wood connections are safe in use. Design methods require the use of analytical methodologies and computational modelling to predict the fire exposure and the components capacity to resist to this action. In this work, the authors present studied cases, that will help professionals to analyse wood-steel connections and focus the type of information needed to decide whether the charred elements are adequate or not to use. For the same wood-steel connections, different insulation materials will be analysed to compare their behaviour and determine the fire resistance in time domain.
- Numerical model to predict the effect of wood density in wood–steel–wood connections with and without passive protection under firePublication . Fonseca, Elza M M; Silva, Lino; Leite, Pedro ASThe main objective of this work is to present a numerical model to predict the effect of wood density in unprotected wood connections with an internal steel plate (wood–steel–wood), when comparing with the same connections using passive protection with gypsum plasterboard, submitted to fire conditions. Wood–steel–wood connections are made of four wood members, two on each side, with an internal steel plate that connects the pieces using steel dowel fasteners. First, analytical methodologies according to Eurocode 5 part 1-1 were used to design the connections at room temperature. After that, to predict the fire exposure and the connection ability, a numerical model was performed which permits to compare the fire resistance in wood–steel– wood connections without and with passive protection following the Eurocode 5 part 1-2. Results of the temperature and the wood char layer depth were compared using three different wood densities. The evolution of the charring rate was calculated in different locations of the connections and compared with the analytical value proposed by the Eurocode 5 part 1-2.
- The Density Effect in (W-S-W) Wood Connections with Internal Steel Plate and Passive Protection under FirePublication . Silva, Lino; Leite, Pedro; Fonseca, Elza M MThe main objective of this work is to understand the fire behaviour of unprotected wood-to-wood connections with internal steel plate (W-S-W) in comparison with connections using passive protection with gypsum plasterboard. Passive fire protection uses systems that help prevent the spread of fire. Analytical methodologies according Eurocode 5 part 1-1 were used to the designed connections in different wood densities material. After that, to predict the fire exposure and the connection capacity a computational modelling was performed. Results of the temperature field and the char layer formation, for unprotected and protected members, were compared. Two different cross sections, only in wood or in wood-steel, were chosen to verify the evolution of charring rate effect.
- The Fire Resistance of (W-W-W) Wood-To-Wood Connections Protected with Different Types of Gypsum PlasterboardPublication . Leite, Pedro; Silva, Lino; Fonseca, Elza M MThe main objective of this work is to verify the fire resistance of unprotected (W-W-W) wood-towood connections and compare the results with protected connections using gypsum plasterboard. According Eurocode 5, part 1-2 the connections could be protected by the addition of wood panelling, wood-based panels or gypsum plasterboard type A, H or F. To obtain conclusions according the application of different type of gypsum plasterboard in the designed W-W-W connections in different densities material, numerical models were building to verify the level of protection in fire action. The wood behaviour varies with temperature and its influences the progressively properties degradation. After fire exposure, it is need to determine if the charred wood connections will rest safe for use. Design methods require the use of analytical methodologies and computational modelling to predict the fire exposure and the components capacity to resist to this action. Results of the temperature field in the studied connections under fire will be presented, with the measured char layer in unprotected members and comparing the protected efficiency with different types of gypsum plasterboard.
- Wood Connections Under Fire Conditions Protected with Gypsum Plasterboard Types A and FPublication . Fonseca, Elza M M; Leite, Pedro A. S.; Silva, LinoThe wood behavior varies with temperature, which has a negative effect, be-ing verified by progressive properties degradation. After fire exposure, it is possible to measure the wood char layer and the remaining resistant cross-section area. Based on numerical models and analytical equations, it is pos-sible to study the protection level of wood connections, during fire exposure, and evaluate wood and steel dowels temperature fields in conjunction. The main objective of this work is to verify the fire resistance of unprotected (W-W-W) wood connections and compare the results with protected connections using gypsum plasterboard. According Eurocode 5, part 1-2 the connections could be protected by the addition of wood paneling, wood-based panels or gypsum plasterboard type A, H or F. To obtain conclusions according the application of different type of gypsum plasterboard in the designed W-W-W connections in different densities material, numerical models were building to verify the level of protection in fire action. Design methods require the use of analytical methodologies and computational modelling to predict the fire exposure and the components capacity to resist to this action. Results of the temperature field in the studied connections under fire will be presented, with the measured char layer in unprotected members and comparing the protected efficiency with different types of gypsum plasterboard.