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Impact sound transmission loss is the ability of structure to absorb impact noise, which is formed by mechanical impulses (steps, falls). The impact noise is then spread to the elements connected to the floor structure, such as the ceiling and surrounding wall. Dynamic stiffness is one of the important parameters that affect the sound insulation of ceiling structures with floating floors. The article deals with the optimal design of acoustic insulation to the floor composition, combining different materials of various thicknesses with various characteristic properties.

Floating floor coverings are widely applied in ship structures. With regard to the laminated composite shells made up of floating floor coverings and cabin deck and based on ANSYS system, a dynamics analysis on structures of three different kinds of floating floors is performed using FEM built upon laminated shell elements. The influence of rockwool board in terms of thickness, density and elastic modulus on structure dynamic characteristics is discussed. The performances of vibration control of three different floating floor structures are compared. The FEM performs well in analyzing and calculating the vibration control characteristics of structures, the results of which offer certain reference to the design and research on cabin deck covered with floating floor coverings.

In order to acquire a high quality of living environment, it is necessary to investigate the subjects of floor impact sound insulation. According to the characteristics of optimization design method and restricted optimization math model, the sound transmission between floor and adjacent room down through floating floor has been modeled in a finite-element method. Floating floor structure are studied to realize the design optimization when the room average sound pressures are selected as objective function. Predicted results show that when keep the whole thickness of floating floor fixed, result of dynamics optimization design can reduce room average sound pressure effectively. And when keep the whole thickness of floating floor unfixed, optimization results have been gotten on the total thickness of floor layer and resilient interlayer of the floating floor, and the average sound-pressure in room is lower than original one availably.

By establishing finite element model of load floor based on the field data, this work evaluated vibration of load floor after isolation measures were taken through effective value of acceleration of vibration. And it demonstrated that the floating floor slab was very useful for vibration isolation for load floor whose buildings have been completed. What’s more, the thesis also provided reference standards for further studies on vibration isolation for load floor caused by large-scale rotating machinery on the floor.