The Acoustical Quality Controlling Study Of Large Space Grid In Gymnasium

The modern gymnasiums gradually become the city's landmarks because of large scale, novelty form and advanced technique. The roof structure of large scale gymnasiums commonly is like large-span spatial grid, and that leads to some defects such as long reverberation time, echo, and sound focusing and so on. Therefore the acoustical quality controlling study is the topic urgently needed to be solved.The gymnasium in Ocean University of China, one of contractor locations of the Eleventh National Games, is studied for its acoustical quality controlling of the large space grid in this paper. Modeling the long-span spatial grid to an inch by the computer simulation software is done for the first time. On this basis,diffusion property of the spatial grid is analyzed and ,give the arrow diagram of some parameters, such as sound pressure level (SPL), definition (D50) and early lateral energy fraction (LF80). When test condition is possessed in the raw gymnasium, the simulation technique is confirmed to be accurate and feasible by comparing the data gained from in-site with the analogue result. And then primary structures of the building are analyzed to propose acoustical controlling design proposal of large space grid in gymnasium.The main method that is adopted to research the sound quality control and explore the best acoustics parameter in this thesis is as follows. The angle in 3D space is calculated by the VC programming to solve the problem of building the accurate model of spatial grid in the acoustical simulation software ODEON. Based on the acoustic characteristic of surface material in the interior of gymnasium, the query system of absorption material is built combining VC with Access by ADO interface. It is facilitate to choose the material in the solution formulation. Select the most accurate estimation method of reverberation time by comparing the analogue result by computer simulation software ODEON with the data gained from in-site by the PULSE data acquisition. The most accurate reverberation time estimation method can provide reliable basis for the work of sound quality controlling. And then primary structures of the building, especially the absorber applied to solve the problem of low-frequency reverberation, are analyzed. The acoustical quality is optimized in the gymnasium ultimately.Finally, Diffuse reflection of sound field in gymnasium is simulated and its main sound parameters such as sound pressure level (SPL), definition (D50), early lateral energy fraction (LF80) are also analyzed, by applying the electro-acoustic system to make up for uneven distribution of sound field in gymnasium. The simulated effect is acted in EASE, which is a sound software used in electro acoustic system design.Given all that, the design approach that this paper has adopted can serve as a guideline for acoustical optimization in space under spatial grid and give directions to the actual acoustical design project in modern gymnasium construction.