This work summarizes the characterization of flint artefacts from the Middle Palaeolithic site 'Abrigo de la Quebrada' (Chelva, Valencia, Spain) and flint geological samples collected in the Chelva area. Additionally, some flint artefacts located outside this geographical zone were also analysed and compared with the samples from the Abrigo de la Quebrada site. Flint samples have been studied using methods of macroscopic description and physicochemical analysis [energy dispersive X-ray fluorescence spectrometry (EDXRF) and X-ray diffraction (XRD)]. Multivariate statistical analysis of the EDXRF data and the determination of the crystalline index of quartz, obtained from the XRD patterns, are suitable methods to discriminate between local and allochthonous flint artefacts in agreement with the macroscopic classification. These results provide new analytical information of the flint artefacts on a geographical area that had not been studied so far.
The use of maritime pine sawn timber in structural applications requires knowledge of its mechanical properties. Standards have changed, however, since the last research on this timber was performed. In the present study, 491 beams of maritime pine from Galicia, of structural-use size but different cross-section, were tested according to these modified standards. Each beam was visually graded according to standard UNE 56.544 and subjected to a four point bending test. The strength classes assigned by the visual grades awarded suggest this material to have greater structural capacity than that currently assumed. The relationships between the modulus of elasticity, strength and density were also examined.Key words: visual grading, strength class, mechanical characterization.
ResumenPropiedades mecánicas de la madera estructural de pino marítimo de Galicia (Pinus pinaster Ait. ssp. atlantica)La utilización de madera aserrada de pino marítimo con fines estructurales requiere del conocimiento de sus propiedades mecánicas. La normativa ha evolucionado desde el último estudio realizado sobre una muestra de pino marítimo de galicia. Por ello en este estudio se han ensayado 491 vigas procedentes de Galicia, con tamaño estructural y de diferentes secciones siguiendo las modificaciones de las normas. Cada viga fue clasificada visualmente siguiendo los criterios de la norma UNE 56.544 y posteriormente se ensayaron a flexión hasta la rotura. Las clases resistententes asignadas a cada calidad visual muestran que el material tiene una capacidad mayor de la normalmente asumida. Finalmente, se obtuvieron modelos de relación entre resistencia, elasticidad, y densidad.Palabras clave: clasificación visual, clase resistente, caracterización mecánica.
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