Research On Structural Performance Of Glued Laminated Bamboo Chairs

With the continuous expansion of industrialized production of furniture,the contradiction between the shortage of timber resources and industrialized production has became increasingly prominent.At the end of the last century,bamboo experts from the State Forestry Administration put forward the idea of "using bamboo instead of wood" to “bamboo wins wood ".Bamboo has been used in furniture production,but there are also problems.The research of bamboo using related mechanical properties less,only understanding of materials,we can better use of materials.In this paper,the research on the structural connection of glued laminated bamboo chairs is carried out.Through the experiment of simulating the destruction of the leg component("L" type component)during the actual using,the following conclusions are obtained:1.Investigate the problems in the using of the seat,analyzed the possible stress state of the seat in using,and find out the root causes of the loosening of the seat structure and the fall of the hardware connector.After the structural analysis of the seat system,the resulting structural model is simplified as "L" type or "T" type.The whole seat is composed of these components.The analysis of the state of force determines that there are two types of forces that can damage the joint of the structure,Open force and Close force,which is the key force that causes the seat metal connection node to break loosening.2.Aiming at the study of loose and destructive problem of the seat in using,the research into the connection of "L" type members("T" empathy).First use the universal mechanics to determine the max-Open force and the max-Close force to destroy.The maximum static load of Open is 160 N and the maximum static load of Close is 200 N.3.Test the fatigue resistance / durability of the structural members with Open Force and Close Force test results of conclusion 2.The test range of the Open Force is 180 N,200N and 220N;the test range of the Close Force is 160 N,180N and 200 N,and the experimental data are measured in the specimen under stress.The experiment separately measured the data of Open force,Close force and impact frequency n and angular displacement ?,assuming that there is a linear relationship between the three within the range of data measurement(there is no linear relationship between force and impact frequency),a binary linear mathematical model is established.The relationship between the angular displacement(?)and Close Force and impact force(F)and impact number(n)is ? =-5.5381 + 0.03195 F + 0.00021 n,where F? [ 160,200],n> 0.The relationship between the angular displacement(?)and the Open force and the impact force(F)and the impact number(n)is ? =-4.8436 + 0.024394 F + 0.00022 n,where F? [180,220],n> 0.From the coefficient of force,the coefficient of Close force is obviously larger than the coefficient of Open force,and the influence of Close force is larger than Open force,which is the main force to cause component failure.From the coefficient of impact times,the coefficient of impact times of Open force approaches Close force,indicating the number of impact on the Open force,Close force impact equivalent.4.Test specimen force(Close force and Open force)state and non-stress state angular displacement relationship,the experiment found that for the Close force: With the increase of the number of impact,the relation between "recovery" of yield deformation and yield deformation increases linearly with the increase of impact times,and the "recovery" of yield deformation is more than 100%.For the Open force,as the number of impact increases,the relationship between the angular displacement recovery of the component without force and the yield of the force statetends to be constant.After 2000 times of test,the value tends to be 30%.The comparison between the two shows that the yielding deformation caused by Close Force is more serious than Open Force.The maximum static load and the fatigue-resistant and durability-damage-related data of the structural connection nodes obtained in this study can guide the factory to improve the design of the structural connection node according to the different requirements of use and produce the corresponding bearing capacity seat products.Further,guide consumers(experience)how to regulate the use of the habit of the seat during use,regular maintenance of seats,to improve the use of experience,to extend the service life.