Preparation And Mechanical Properties Evaluation Of Glued Laminated Bamboo

Nowadays most of widely used bamboo engineering structural materials, includingBamboo plywood, Bamboo mat plywood, Bamboo curtain plywood, Bamboo particle board,Laminated bamboo strip lumber and Reconsolidated bamboo, don’t have stable quality becausethere is no strict standard to observe in their production processes, so reliable basic data canhardly be gained while safty and reliability of materials can’t be guaranted, which leads tostructure can’t be designed and strength can’t be predicted, as a result most of bambooengineering structural materials can’t be used in many situation where require high safty andreliability.Using Moso bamboo strips near the bamboo green as raw materials, part of its mechanicalproperties were measured, and Moso bamboo strips near the bamboo green were graded andspecific grading performance standards were established. Using graded Moso bamboo stripsnear the bamboo green, urea-formaldehyde resin and phenol-formaldehyde resins as rawmaterials, and non-continuous stitched and continuous stitched assemble patterns were used,three kinds of glued laminated bamboo were made by glueing, assemble and hot pressing,including UF glued laminated bamboo(non-continuous stitched), PF glued laminatedbamboo(non-continuous stitched) and PF glued laminated bamboo(continuous stitched);mechanical properties of the three kinds of glued laminated bamboo were measured andcompared. Mainly conclusions and innovation of this research are listed as follows:1) The means of tensile shear strength of radial and tangential of Moso bamboo strips nearthe bamboo green were12.71MPa and7.98MPa respectively;2) MOE and MOR of Moso bamboo strips near the bamboo green linearly increased withair-dry density under radial loading pattern (the bamboo green is above/below) and tangentialloading pattern; correspond to above-mentioned three kinds of load patterns, MOE of Mosobamboo strips near the bamboo green are16.63GPa,15.74GPa and17.07GPa while MOR are211.64MPa,237.66MPa and219.56MPa; under different load patterns bendingperformance of Moso bamboo strips near the bamboo green was different, and it indicated thatload pattern has significant effect on bending property of Moso bamboo strips near the bamboogreen; According to air-dry density of simples and MOE under tangential load pattern, Mosobamboo strips near the bamboo green were graded for the first time in China, and theproperties of graded Moso bamboo strips near the bamboo green were uniform and stable;3) Using urea-formaldehyde resin and phenol-formaldehyde resins, and by non-continuousstitched and continuous stitched assemble patterns, three kinds of glued laminated bamboowere made. Result of technical test showed that: the technology of non-continuous stitchedassemble pattern was simple and developed while the technology of continuous stitchedassemble pattern was innovative, relatively complicated and developing;4) All of the three kinds of glued laminated bamboo have excellent bonding performanceand their tensile shear strength are higher than6.5MPa; from an overall point of view, twokinds of PF glued laminated bamboo have higher mechanical strength than UF glued laminatedbamboo.