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Given the importance of wood as a building material for hundreds of years, it is often necessary to increase the resilience of existing wood elements. Due to their notable adaptability and high mechanical capacities, materials composed of polymers that have been reinforced with fibers represent a good alternative to traditional reinforcement systems. This study looks at the compressive behavior of prismatic wild pinewood test pieces confined with three types of fabric—one of carbon fiber reinforced polymer (CFRP) and two of basalt fiber reinforced polymer (BFRP) featuring two very different grammages. The reinforced pieces attain at least 96% greater resistance than the unreinforced pieces (FC300), reaching as much as 133% more resistance in the case of the pieces reinforced with FB600; however, the ductility of the reinforced pieces is much lower than that of the unreinforced, by approximately one-sixth and one-quarter, respectively. The study also allowed us to conclude that there is no relationship between the mechanical capacity of the reinforcement and the ultimate strength of the test piece tested, but there is a strong relationship between the rigidity of the reinforcement and modulus of elasticity and the ultimate strain of the reinforced pieces.

ResumenEn este trabajo se realiza un estudio experimental del comportamiento de dieciocho vigas de madera aserrada para uso estructural, de dimensiones 155x75x1090mm. La madera empleada ha sido de pino silvestre de Valsaín. Los ensayos se han realizado en el Laboratorio de Materiales de Construcción de la Escuela Técnica Superior de Edificación de Madrid. El objetivo del trabajo es el análisis del comportamiento a flexión de las piezas ensayadas teniendo en cuenta de los defectos y singularidades que presentan, realizando un estudio de la influencia de éstos. Se han ensayado dieciocho piezas en total, de las cuales nueve se colocaron en posición plana y las otras nueve de canto. Antes de proceder a los ensayos, la muestra ha sido clasificada según la norma UNE 56544 de clasificación visual de la madera aserrada para uso estructural, determinándose la calidad estructural de cada pieza y la clase resistente teniendo en cuenta que la especie de la madera es pino silvestre. Se identifican las singularidades y defectos que presenta cada una de las piezas y se mide la humedad, el peso y dimensiones de éstas. En las conclusiones se presentan los resultados del análisis realizado, comparando los datos de los ensayos con las características de las piezas, determinando la influencia de la presencia de defectos y las características de las piezas con sus propiedades mecánicas. AbstractThis paper presents an experimental study of the behavior of 18 timber beams for structural use of 155x75x1090mm dimensions. The origin of the wood is Valsaín sawmill. The tests were performed at the Laboratory of Construction Materials at the University School of Technical Architecture. The objective of this work is the analysis of flexural behavior of test pieces according to the defects and singularities, carrying out an analysis of their influence. 18 pieces have been tested, of which 9 were placed in a flat position, and the other 9 were placed in edge position. Before testing, the samples were classified according to UNE 56544 visual grading of sawn timber for structural use, determining the structural quality of each piece and the strength class. Singularities and defects found in each one of the pieces, moisture, weight and dimensions are measured and identified. The results of the analysis are presented in the conclusions, comparing the test data with the characteristics of the beams, determining the influence of the presence of defects and the characteristics of the timber beams with resistance in tests.Index Terms—