Vibration Analysis Of Truss-like Lattice Sandwich Structure With Defects

The lattice sandwich structure is a kind of excellent mechanical properties ofultralight porous periodic structure, which is widely used in aviation, aerospace,ships, buildings and ordnance industry. Truss-like lattice sandwich structure isinvestigated in this paper, an improved structure is proposed based on the latticesandwich structure. In this paper, a new manufacture process of composite materialstruss-like lattice sandwich structure is presented, and free vibration properties oftruss-like lattice sandwich structure are studied by the methods of numericalsimulation and experimental measurement.First of all, the structure parameters are optimized under shear loadingconditions. The corrugated plate mold is designed according to the optimizedgeometry parameters, and the composite materials truss-like lattice sandwichstructures are prepared by one new manufacture process.Secondly, free vibration properties of truss-like lattice sandwich structure arestudied by the methods of numerical simulation and experimental measurement. Theeffects of the boundary conditions, ply angle of the panels and core, the upper andlower panels thickness difference as well as panel thickness on the natural mode ofvibration of truss-like lattice sandwich structures are investigated.Finally, in view of the structural defects that may occur in the course ofpreparation or serving, free vibration properties of truss-like lattice sandwichstructure with defects are studied further. The influence of skin-core debonding,panel delamination, core member deletion and core bars delamination on the naturalfrequencies and natural modes of vibration is discussed. The study has importantpractical significance to prevent the occurrence of resonance and ensure thestructural safety and reliability.