Experimental Study On Fire Resistance Of Glued Bamboo Columns Under Axial Compression

Because of its lightweight,high-strength,green environmental protection and superior mechanical properties,laminated veneer bamboo has attracted more and more attention.The existing research on the structure of laminated veneer bamboo as a new type of assembly structure system is not mature,especially the mechanism of the stress and the catastrophe mechanism under the fire of the laminated veneer bamboo members has not been reported.In order to further promote the application of laminated veneer bamboo in practical engineering,the mechanical properties and carbonization properties of the laminated veneer bamboo columns under axial compression are studied in this paper.In combination with the finite element simulation and theoretical analysis,the changing rules of the bearing capacity and the fire resistance limit of the laminated veneer bamboo columns under fire are revealed.the main research contents and results include the following aspects:(1)By carrying out the axial compression test of the laminated veneer bamboo column with the slenderness ratio of 30~65,the parameters of the deflection,strain,axial deformation and failure form were analyzed,and the mechanism and failure mechanism of the bamboo column under the axial compression were revealed.(2)The ABAQUS finite element software is used to carry out the numerical simulation of the axial compression of the laminated veneer bamboo at normal temperature,and the precision model of the calculated results is obtained by comparing the results of the test.Then the analysis is extended to obtain the law of the bearing capacity of the big slenderness ratio of the bamboo column,which provides the basis for the analysis of the finite element parameters under the fire.(3)According to the characteristics of laminated veneer bamboo,the analysis method of equivalent elastic modulus with two factor is used to deduce the calculation formula of ultimate bearing capacity of the axially compressed bamboo column.(4)By carrying out the test on the axial compression of the laminated veneer bamboo column under the fire,the influence of the holding ratio and the slenderness ratio to the fire resistance limit is obtained.And the obscission phenomenon was observed providing data support for theoretical analysis under fire.(5)The ABAQUS finite element software is used to carry out the numerical simulation of the axial compression of the laminated veneer bamboo column under fire,and the precision model of the calculated results is obtained by the comparison and analysis of t he test results,and then the influence the holding ratio,the slenderness ratio and the volume to the fire resistance of the laminated veneer bamboo column is explored.(6)According to the method of Eurocode 5: Design of timber structures,bearing capacity and the limit of fire resistance of the bamboo column under the axial compression at high temperature is theoretically derived,and the corresponding examples are given in detail.