The Study On Bonding Property And Aging Resistant Performance Of Glulam Members

This paper mainly discusses and studies bonding property and aging resistant performanceof glulam members by several accelerated aging methods：According to the results of the shearing strength and wood failure of specimen，wood failurereaches to91%，average shear strength of dry condition is about8.27Mpa；looking for the wetcondition，wood failure is about90%，average shear strength is more than4.0Mpa．The resultsindicate that shear strength under dry and wet conditions could meet the requirements of GB50005－2003，and the relationship of shear strength and wood failure percentage(WFP) meetsthat of ISO/DIS12578．The delamination testing methods are conducted according toGB/T26899-2011andISO/DIS12580．It shows that the values of bonding strength delaminating of glulam membersare less than5%after water soak and water boiling delamination testing．After2cycles，thesingle layer of the maximum delamination is about9%，the degree of delamination of thespecimen with vacuum－pressure delamination testing is slightly smaller than the other twoways．According to four kinds of manual accelerated aging methods，including ASTMD1037，BSEN1087－1，CAN/CSA－0188，ASTM D3434following conclusions are obtained：After aging processing，the decline of shear strength which is the most significant is between27.8%and44.9%．On the basis of this conclusion，it can be advised to take the shear strength asone important factor for aging resistant performance of glulam member．Performances of glulam members which are treated by BS EN1087－1and ASTM D1037accelerated aging methods are alike somehow．BS EN1087－1accelerated aging processingtakes less hours，so the previous one is much better in application for its time saving．The correlations are all significant at0.01level for glulam members which treated byASTMD1037，BS EN1087－1and CAN/CSA－0188accelerated aging method as the thicknessswelling being more correlative than the thickness swelling of24hours’ water absorption．After ASTM D1037accelerated aging processing，MOR，MOE and shear strength of glulammembers fit exponential and logarithm curve better．After BS EN1087－1accelerated agingprocessing，for MOR，MOE and shear strength，logarithm curve and power curve fit better．AfterCAN/CSA－0188accelerated aging processing，the power curve fit of MOR，MOE and shearstrength is significant at0.05level，the logarithm curve fit of MOR and MOE is significant at0.05level．The curve fits good．...