Design And Study Of Mechanical Properties Testing Apparatus For Large-size Wood Composite Panels

The most common size of wood composite panels is 2440mm x 1220mm in production and sale,but there are other more larger sizes of specifications.Large-size wood composite panel refers to the panels with thickness of 5mm to 25mm and width of not less than 2440mmx 1220mm,including fiberboard,particleboard and plywood.Wood composite panels have good structure performance and stable size,so they are widely used as interior decoration materials,furniture and building materials,or packing boxes during transportation.According to different using environments and applications,the demands of mechanical properties are different.So,the fast and non-destructive test of large-size for wood composite panels mechanical properties is fairly important to provide some data base.Previous studies have shown that basing on the transverse free vibration theory could exercise non-destructive tests of mechanical properties of full-size wood composite panels.This paper is based on the studies,and an independent mechanical properties testing apparatus for large-size wood composite panels is designed and exploited.The main work includes:the mechanical structure design of the testing apparatus,the design and fabrication of the electrical box,the design of the mechanical properties testing program,experiments carried out by using the developed apparatus,then verify the accuracy and reliability of the testing apparatus and experiment results.The main work of this paper is the overall design of the testing apparatus and the test of the several vibration frequencies simultaneously.The testing apparatus adopts structure of aluminum,and both the length direction and the width direction could be adjusted in order to adapt to the large panels with common specifications of different size.Use the LabVIEW to write the testing program to test the mode vibration frequencies from the first order to the ninth one,and extract the three frequencies which we want,so as to realize the panels modulus of elasticity in length and width direction and the in-plane shear modulus could be tested simultaneously.The research results prove that the developed mechanical properties testing apparatus for large-size wood composite panels could test accurately and reliably,which can be operated easily and developed and promoted potentially.