The Influence Of Flax Fiber Reinforced Polymer Pasted Along Beam Height On The Bending Performance Of Glulam Beams

Nowadays,the goals of carbon peaking and carbon neutrality proposed by our country show our country’s determination to pursue sustainable development,and green building mate-rials have a positive impact on reducing carbon dioxide emissions.As a renewable modern en-gineering wooden material,glulam has developed rapidly in the construction industry in recent decades due to its structural characteristics and aesthetics.However,the bearing capacity and rigidity of ordinary glulam beams are low,and sudden brittle failure is prone to occur in engi-neering.Toavoid the brittle failure of glulam beams,and solve the problems of low bearing ca-pacity,large deformation,small rigidity and split failure along the longitudinal direction of glu-lam beams,the research team has studied a new method of reinforced glulam beams with mod-ified flax fiber cloth.Flax fiber and glulam are both biomass materials,which are green,envi-ronmentally friendly,sustainable,and renewable.The structural components produced by this material can give people a sense of safety and comfor,and are ecological products worth pro-moting in today’s society.In this test,flax fiber cloth was used as a reinforcing material,and modified flax fiber cloth was prepared by TiO2 graft modification to improve its mechanical properties.SPF mate-rial glulam beams were selected with a size of 2850mm×50mm×150mm.According to the number and method of pasting different modified fax fiber cloths to the glulam beams,they are divided into 7 groups,with 3 pieces in each group.The three-point loading test of glulam beams was carried out to study the effect of laterally pasting modified flax fiber cloth on the bending performance of glulam beams.The results of this study show that when only 6 layers of modified flax fiber cloth are pasted on the bottom of the glulam beam,the failure mode of the wood beam is brittle failure.When the U-shaped hoops or ring hoops are pasted to the woodern beams in the transverse di-rection,the cracking between the beams and plates can be restrained.The cooperative working ability between the modified flax fiber cloth and the wooden beams can be improved,and the damage form of the wooden beams can be changed.On the premise of pasting 6 layers of mod-ified flax fiber cloth on the bottom of glulam beams,the ultimate bearing capacity of wood beams is significantly improved by laterally pasting 6 layers of U-shaped hoops compared with 3 layers of U-shaped hoops,but the increase in bending stiffness is small.Compared with 3-layer ring hoops,the horizontally pasted 6-layer ring hoops can significantly improve the ulti-mate bearing capacity and flexural rigidity of wooden beams.Compared with the transverse pasting of U-shaped hoop,the effect of transversely pasting ring hoops on the ultimate bearing capacity and flexural rigidity of wooden beams is more obvious.Therefore,the method of transversely pasting ring hoops is more reasonable.On the premise that the glulam beam is pasted with 6 layers of U-shaped hoops transversely,the effect of sticking 6 layers of modified fax fiber cloth on the bottom on the ultimate bearing capacity and bending stiffness of the wood beam is greater than that of 3 layers of modified fax linen fiber cloth pasting on the bot-tom.Therefore,the 6-layer modified fax fiber cloth pasted on the bottom and the horizontally pasted hoop work together better.The beam is modeled and analyzed by ABAQUS finite element software.The glulam beam is used as the solid element and the flax fiber cloth is used as the shell element to estab-lish a finite element model of the glulam beam reinforced by transversely pasting U-shaped hoops and ring-shaped hoops.The comparison between the analysis value and the test value proves the rationality of the finite element model,other parameters that affect the bending per-formance of glulam beams are analyzed.Finally,a suggestion on the way to strengthen glulam beams was given.