Three-dimensional optical deformation measurement of laminated veneer lumber and the finite element simulation analysis of the pallets

ObjectiveThe laminated veneer lumber has been widely used, but its mechanical properties were mostly conducted using destructive methods, which possesses drawbacks like low efficiency and wasting of resources. In this study, a new laminated veneer lumber (NLVL) and the NLVL-made pallets were nondestructively tested, aiming at providing theoretical reference and technical support for detecting the properties of the laminated veneer lumber and its products efficiently and accurately.

MethodThe three-dimensional optical deformation measurement with the finite element analysis method was combined, the elastic constants of the NLVL were firstly measured and calculated by three-dimensional optical deformation test, including the elastic modulus, poisson’s ratio, shear modulus, which were used as basic parameters for the static simulation. The layer element and solid 185 element were selected respectively for mesh generation and static simulation of the laminated wood model, and the simulation parameters were optimized. The performance of the NLVL-made pallets was tested according to the international standard ISO 8611−2011. The pallet model was built and assembled using Solidworks, and the overall structure of the pallet was simulated under four working conditions including pressure resistance, bottom runner, surface strength and corner drop in ANSYS workbench software, and the simulation results were compared with the experimental test results.

ResultThe study showed that the data gained from three-dimensional optical deformation measurement can be used as parameters in the finite element simulation analysis of the NLVL and its products, the simulation results were close to that of the experimental test. The results were mostly matched when the NLVL was considered as unit and the solid 185 was selected during the simulating analyses. In the static simulation analysis of the NLVL-made pallets, the maximum deformation of the tray was close to the experimental results. The simulation results of the four working conditions were the same as the measured results

ConclusionThis nondestructive method which combined the three-dimensional optical with finite element simulation can be used to analyze the stress, deformation and failure of wooden laminates and their products, therefore, it is possible to achieve the goal of energy saving and high efficiency.