Abstract
The authors investigated the properties of small-sized joint-free laminated beams (80 mm in width, 115 mm in height and 2 m in length) composed of 7 mechanically graded laminations of poplar (Populus x euramericana, 'Neva' clone) and eucalyptus (Eucalyptus grandis, '7', '329', '330' and '358' clones) in different combinations. Tests were carried out in order to determine their modulus of elasticity, bending strength and shear modulus; the bonding reliability was also evaluated by means of delamination and shear tests in the glue lines. The beams composed using the '330' eucalyptus clone, by its own or in combination with poplar, showed outstanding mechanical performance and the best structural efficiency. In addition the bonding quality, also at the interface between the two species, proved to be excellent. The results, separately for each clone of E. grandis, in terms of absolute values and structural efficiency, are shown and discussed.
Zusammenfassung
Die Autoren untersuchten die Eigenschaften von kleinen verbindungsfreien Brettschichtträgern (von 80 mm Breite, 115 mm in Höhe and 2 m Höhe) zusammengesetzt aus 7 mechanisch sortierten Brettschichthölzern von Pappel (Populus x euramericana, 'Neva' clone) und Eucalyptus (Eucalyptus grandis, '7', '329', '330' und '358' Klonen) in unterschiedlichen Kombinationen. Tests wurden durchgeführt, um ihr Elastizitätsmodul, ihre Biegefestigkeit und Scherfestigkeit zu bestimmen; die Haftverläßlichkeit wurde ebenfalls abgeschätzt durch Delaminierung und Schertests in den Klebefugen. Die zusammengestellten Balken, bei denen man den 330 Eukalyptusklon verwendete, entweder allein oder in Kombination mit Pappel, zeigten herausragende mechanische Qualität und die beste strukturelle Leistungsfähigkeit. Zusätzlich erwies sich die Bindefestigkeit, auch an den Grenzflächen zwischen den beiden Arten als exzellent. Es werden die Ergebnisse separat für jeden Klon von E. grandis, als absolute Werte und als strukturelle Leistungsfähigkeit dargestellt und diskutiert.
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Castro, G., Paganini, F. Mixed glued laminated timber of poplar and Eucalyptus grandis clones. Holz Roh Werkst 61, 291–298 (2003). https://doi.org/10.1007/s00107-003-0393-6
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DOI: https://doi.org/10.1007/s00107-003-0393-6