The Acoustic Characteristics Research Of Multilayer Composite Material

With the continuous development of science and technology, problems of information security are becoming more and more anxious for people, which also involves individual, collective, social, even national security and social stability. In the physical protection field of information security, for specialized facilities of sensitive meetings, sensitive work and sensitive information, the official introduced relevant electromagnetic protection standards, particularly the demanding about sensitive meeting room, from distance defending to sound, light, and electricity integrated protection. As one of the most basic information carrier, to protect the sound is the key of information security, at the same time it's a priority for the protection of information. While the partition as one of the main form of sound protection, the traditional sound insulation partition body already cannot satisfy the need of modern information security, which mainly displayed in the following two aspects: on the one hand, sound insulation quantity can't meet the relevant requirements; on the other, they did not have other protective measures-electromagnetic protection and light protection. The author proposed the partition was a composite structure which used metal plates as substrate,and the partition can effectively make up for the deficiency existing in the traditional one. Mainly around with sensitive meeting rooms of information security as the background, and structure of lightweight wall as the research object, considering the various factors affecting the existing information security, this article researched sound insulation protection of the structure.Combination the requirements of sensitive meeting rooms protection, the article analyzed the traditional light weight partition's structure and sound insulation property, aiming the high-performance sound protection demanding, and designed multi-layer composite structure with metal plate as the base based on the predecessors' research and practice, three basement structure and five base model, from single to multilayer, to the complete structure model "quality- spring- quality", analyzing the model of the structure and the material selection and the effect of acoustic features, and showed the 3D structure schematic diagram. The author also used the Sharp theory to predict and analyze sound insulation quantity of multilayer structure initially by the analysis the theory of sound insulation structure model based on the theory of single and double layers in the traditional structure, and according to the theory of structure model and tested in the laboratory to establish the actual components.After the sound insulation test to the actual component established in accordance with the relevant testing theory and standards, compared the testing data and theory data, the results from the theoretical formula t were basically same with the actual test data, which can better responding the structure of the sound insulation performance; Through analyzing the acoustic performance of the center frequency of different structure in acoustic frequency characteristic curve, the results showed that the damping structure can weaken the decreased acoustic phenomenon caused by resonance and consistent effect, and the sound insulation performance model with constrained damping structure was better than that of free damping of the structure of the model; and compared the sound insulation performance of different structure with same material and different material components with same structure respectively. Composite structure composed by composite materials all had high volume of sound insulation, sound insulation quantity of five kinds of model were in more than 50 d B, and the thickness of structure were around 100 mm, the thinnest thickness of the structure was 96.7 mm, and the sound insulation quantity up to 54 dB; Compared with traditional light sound insulation wall body, sound insulation quantity was high, and the thickness was significantly less than traditional structure, the structure had the very good advantage in the application.Integrated the research of the structure composed of multilayer composite materials in this article, the composite structure not only had sensitive meeting room related electromagnetic shielding function, and also meet the demand of sound corresponding protective high sound insulation; The structure model had high practical value, and also had certain reference value for the acoustic research of following metal sheet composite structure.