The effect of long and short term elevated temperatures on the behaviour of lap glued joints of load-bearing spruce elements

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26110%2F24%3APU150100" target="_blank" >RIV/00216305:26110/24:PU150100 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0143749623002555?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0143749623002555?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijadhadh.2023.103575" target="_blank" >10.1016/j.ijadhadh.2023.103575</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The effect of long and short term elevated temperatures on the behaviour of lap glued joints of load-bearing spruce elements

Popis výsledku v původním jazyce

The paper deals with the behaviour of glued joints of wooden sections exposed to long and short term elevated temperatures. If the adhesive is not sufficiently temperature resistant, the glued joint may lose adhesion, which could result in a change in behaviour of the glued element cross-section when exposed to fire. Moreover, detailed knowledge of the behaviour of bonded joints under such long and short term thermal exposures will enable us to make informed decisions about the need for major structural intervention in structures post exposure. Three types of adhesives: phenol-resorcinol-formaldehyde (PRF), polyurethane (PUR) and emulsion polyisocyanate (EPI), commonly used in load bearing wooden structures, were chosen for the experimental work. Thermal analysis showed that the PRF and PUR were not sufficiently cured, especially the PRF. Calorimetric analysis showed the point at which thermal degradation of all three adhesives began, at 135 degrees C for EPI and at about 160 degrees C for PRF and PUR. Spruce lap joints, with a cross section of 40 x 48 mm, bonded using these adhesives were exposed to temperatures of 140 and 170 degrees C. To properly distinguish the effect of thermal exposure duration on the lap joints, different thermal durations were used: 20, 40, 60 and 80 min, plus 3 h and 1 day. The thermal resistance at each of the elevated temperatures was investigated through measurement of the reduction in tensile shear strength. At an elevated temperature of 140 degrees C there was no significant strength reduction in all of the tested adhesives, it was only a longer duration (1 day) that produced a reduction in the tensile shear strength properties (31.0% for PRF, 16.2% for PUR and 34.1% for EPI). A temperature of 170 degrees C produced a greater decrease in strength, a significant drop (more than 15%) was found for PRF and EPI after an exposure of 40 min; for PUR after 60 min. Moreover, the longer duration exposures to a temperature of 170 degrees C resu

Název v anglickém jazyce

The effect of long and short term elevated temperatures on the behaviour of lap glued joints of load-bearing spruce elements

Popis výsledku anglicky

The paper deals with the behaviour of glued joints of wooden sections exposed to long and short term elevated temperatures. If the adhesive is not sufficiently temperature resistant, the glued joint may lose adhesion, which could result in a change in behaviour of the glued element cross-section when exposed to fire. Moreover, detailed knowledge of the behaviour of bonded joints under such long and short term thermal exposures will enable us to make informed decisions about the need for major structural intervention in structures post exposure. Three types of adhesives: phenol-resorcinol-formaldehyde (PRF), polyurethane (PUR) and emulsion polyisocyanate (EPI), commonly used in load bearing wooden structures, were chosen for the experimental work. Thermal analysis showed that the PRF and PUR were not sufficiently cured, especially the PRF. Calorimetric analysis showed the point at which thermal degradation of all three adhesives began, at 135 degrees C for EPI and at about 160 degrees C for PRF and PUR. Spruce lap joints, with a cross section of 40 x 48 mm, bonded using these adhesives were exposed to temperatures of 140 and 170 degrees C. To properly distinguish the effect of thermal exposure duration on the lap joints, different thermal durations were used: 20, 40, 60 and 80 min, plus 3 h and 1 day. The thermal resistance at each of the elevated temperatures was investigated through measurement of the reduction in tensile shear strength. At an elevated temperature of 140 degrees C there was no significant strength reduction in all of the tested adhesives, it was only a longer duration (1 day) that produced a reduction in the tensile shear strength properties (31.0% for PRF, 16.2% for PUR and 34.1% for EPI). A temperature of 170 degrees C produced a greater decrease in strength, a significant drop (more than 15%) was found for PRF and EPI after an exposure of 40 min; for PUR after 60 min. Moreover, the longer duration exposures to a temperature of 170 degrees C resu

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20400 - Chemical engineering

Projekt

<a href="/cs/project/GA21-20645S" target="_blank" >GA21-20645S: Charakterizace vlastností modifikovaných lepidel na bázi izokyanátu pro speciální lepené aplikace dřevěných prvků</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

International Journal of Adhesion and Adhesives

ISSN

0143-7496

e-ISSN

1879-0127

Svazek periodika

129

Číslo periodika v rámci svazku

February 2024

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

„“-„“

Kód UT WoS článku

001125255800001

EID výsledku v databázi Scopus

2-s2.0-85177996888