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The performance of the composites is influenced by the service life of input raw wood material and used adhesives. The aim of the study was to assess the durability and mechanical performance of glulam beams treated in a different way (thermally modified and/or treated with copper-based wood preservative) and exposed in an outdoor application. Glulam beams (83 mm × 68 mm × 1100 mm), made of three layers of Norway spruce (Picea abies) with PUR adhesives used have been exposed in use class 3.2 in a horizontal position since 4th November 2016. Part of the specimens was equipped with MC sensors. Every year, the degradation was evaluated visually. The dynamic modulus of elasticity was determined by longitudinal vibration, and the static modulus of elasticity using a 4-point bending test. On the smaller specimens, cut from glulams, compressive strength, delamination, and shear strength of adhesive bonds were determined. After two years of exposure, the results indicate that the performance of glulams is determined by the wood modification and applied wood preservative.

The performance of the composites is influenced by the service life of input raw wood material and used adhesives. The aim of the study was to assess the durability and mechanical performance of glulam beams treated in a different way (thermally modified and/or treated with copper-based wood preservative) and exposed in an outdoor application. Glulam beams (83 mm × 68 mm × 1100 mm), made of three layers of Norway spruce (Picea abies) with PUR adhesives used have been exposed in use class 3.2 in a horizontal position since 4th November 2016. Part of the specimens was equipped with MC sensors. Every year, the degradation was evaluated visually. The dynamic modulus of elasticity was determined by longitudinal vibration, and the static modulus of elasticity using a 4-point bending test. On the smaller specimens, cut from glulams, compressive strength, delamination, and shear strength of adhesive bonds were determined. After two years of exposure, the results indicate that the performance of glulams is determined by the wood modification and applied wood preservative., Na svojstva kompozita utječu trajnost sirovine i svojstva primijenjenih ljepila. Cilj ovog istraživanja bio je procijeniti trajnost i mehanička svojstva različito obrađenih lameliranih nosača (toplinski modificiranih i/ili impregniranih bakrom) izloženih u eksterijeru. Lamelirani nosači (83 mm × 68 mm × 1100 mm) izrađeni su od tri sloja smrekovine (Picea abies) koji su slijepljeni PUR ljepilom. Nosači su prema klasi uporabe 3.2 izloženi u vodoravnom položaju od 4. studenoga 2016. u trajanju od dvije godine. Na dio uzoraka postavljeni su senzori za mjerenje sadržaja vode u njima. Svake je godine vizualno ocjenjivano propadanje uzoraka. Dinamički modul elastičnosti određen je longitudinalnom vibracijom, a statički modul elastičnosti savijanjem u četiri točke. Na manjim uzorcima ispiljenima od nosača određena je tlačna čvrstoća, delaminacija i čvrstoća lijepljenog spoja na smicanje. Nakon dvije godine rezultati izlaganja pokazali su da svojstva lameliranih nosača ovise o toplinskoj modifikaciji drva i sredstvu za impregniranje.

Ten different samples from Slovenian hardware stores were analysed. Samples were treated with copper based wood preservatives that were designed and advertised to be used in heavy duty applications in ground (use classes 4) and above ground (use classes 3.2). Retention and fungicidal properties were determined in order to establish the quality of treatment quality. Retention was determined by XRF analysis, while a modifi ed EN 113 procedure was applied for the assessment of fungicidal properties. Two brown rot fungal species, Gloeophyllum trabeum and Fibroporia vaillantii, were used for durability testing. The results of the analysis clearly showed that only three of the inspected wood products met penetration requirements, and none of them had sufficient retention, which is also reflected in insufficient durability against wood decay fungi., Za potrebe ovog rada analizirano je deset različitih uzoraka iz slovenskih prodavaonica građevnog materijala. Uzorci su tretirani zaštitnim sredstvima na bazi bakra namijenjenim i preporučenim za zahtjevne uvjete primjene u tlu (uporabna klasa 4) i iznad tla (uporabna klasa 3.2). Određeni su retencija i fungicidna svojstva tih sredstava kako bi se utvrdila kakvoća zaštite drva. Retencija zaštitnog sredstva određena je uz pomoć XRF analize, dok je modificirani postupak EN 113 primijenjen za procjenu fungicidnih svojstava zaštitnih sredstava. Za testiranje trajnosti poslužile su dvije vrste gljivica smeđe truleži, Gloeophyllum trabeum i Fibroporia vaillantii. Rezultati analize jasno su pokazali da su samo na tri istraživana drvna proizvoda bili ispunjeni zahtjevi penetracije zaštitnog sredstva, a ni na jednome drvnom uzorku nije postignuta dovoljna retencija zaštitnog sredstva, što se očituje i nedostatnom trajnošću drva izloženoga djelovanju gljiva truležnica.

The application of wood in seawater is one of the most challenging. Impregnated wood is exposed to leaching and to various marine borers, Limnoria sp. and Teredo sp. being the most important ones. The present research investigated the durability of pine wood impregnated with copper-amine based preservative solution (Silvanolin) of different concentrations exposed to the seawater according to EN 275 standard. Performance of Silvanolin treated wood was compared to the performance of reference wood (Quercus sp., Castanea sativa, Larix decidua). After 10, 18 and 32 months of exposure, specimens were removed and assessed. The results show clearly that the reference wood species were completely degraded after 10 months of exposure. On the other hand, it became evident that Silvanolin prolonged the service life of wood exposed to the sea. The specimens impregnated with the lowest concentration of preservative solution (cCu = 0.31 %) were slightly decayed. The specimens, impregnated with higher concentrations of copper (cCu > 0.31 %), showed almost no defects after expsore to marine borers.

Recovered wood is frequently contaminated with biocides and therefore its use is limited. Even more, wood, impregnated with classical chromated copper arsenate (CCA) preservatives is classifi ed as a hazardous waste, therefore solutions for reuse or recovery of this material are sought. One of the options, discussed in this paper is liquefaction and further applications of liquefi ed wood containing biocide remainings. In order to elucidate this possibilty, spruce and beech wood was impregnated with liquefi ed CCB treated and untreaded spruce wood of various concentrations and exposed to wood decay fungi according to the EN 113 procedure. In paralel, the leaching experiments (ENV 1250-2) were performed as well. The results do not clearly show that liquefi ed wood is bio-inactive. In most cases the mass loss by fungal attack is decreased compared to the untreated controls. On the other hand, copper leaching from spruce wood, impregnated with the liquefi ed CCB treated wood was signifi cantly reduced. Thus, there are indications that the liquefi ed wood could be utilized as a binding agent for inorganic biocides.

The application of wood in seawater is one of the most challenging. Impregnated wood is exposed to leaching and to various marine borers, Limnoria sp. and Teredo sp. being the most important ones. The present research investigated the durability of pine wood impregnated with copper-amine based preservative solution (Silvanolin) of different concentrations exposed to the seawater according to EN 275 standard. Performance of Silvanolin treated wood was compared to the performance of reference wood (Quercus sp., Castanea sativa, Larix decidua). After 10, 18 and 32 months of exposure, specimens were removed and assessed. The results show clearly that the reference wood species were completely degraded after 10 months of exposure. On the other hand, it became evident that Silvanolin prolonged the service life of wood exposed to the sea. The specimens impregnated with the lowest concentration of preservative solution (cCu = 0.31 %) were slightly decayed. The specimens, impregnated with higher concentrations of copper (cCu > 0.31 %), showed almost no defects after expsore to marine borers., Primjena drva u morskoj vodi jedna je od najizazovnijih primjena drva. Impregnirano drvo izloženo je ispiranju te raznim morskim štetnicima, pri čemu su Limnoria sp. i Teredo sp. među najštetnijima. U radu je prikazano istraživanje trajnosti borova drva impregniranoga zaštitnom otopinom na bazi bakar-amina (Silvanolin) različitih koncentracija i izloženoga morskoj vodi prema normi EN 275. Izgled drva zaštićenog Silvanolinom uspoređen je s izgledom referentnoga drvnog materijala (Quercus sp., Castanea sativa, Larix decidue). Nakon 10 , 18 i 32 mjeseca izlaganja morskoj vodi, uzorci su izvađeni te ocijenjeni. Iz dobivenih se rezultata može jasno vidjeti da su uzorci referentnog drva nakon 10 mjeseci bili potpuno razgrađeni. Nasuprot tome, pokazalo se da Silvanolin produžuje vijek trajanja drva u moru. Uzorci impregnirani otopinom zaštitnog sredstva najmanje koncentracije (cCu = 0,31 %) blago su istrunuli. Uzorci impregnirani otopinom zaštitnog sredstva s većom koncentracijom bakra (cCu > 0,31 %) nisu pokazali gotovo nikakva oštećenja nakon izlaganja morskim štetnicima.