| From the micro-level analysis, concrete can be regarded as the three-phase non-homogeneous that composeed a coarse aggregate, cement mortar and the combination. This paper mainly analysed the dynamic characteristics of the materials by the method of Experimental Modal Analysis and the finite element. The key of this paper focus on research of the identification of integration dynamic parameters and it's effects on concrete damping.In this paper, these standard beams of coarse aggregate,mortar and combination were made for simulating micro-concrete structure of concrete. The dynamic properties parameters of coarse aggregate, cement mortar and the combination are obtained through modal testing, such as natural frequency, damping ratio and the transfer function. The transfer function matrix of combination was deduced by the theoretical method of structural dynamics and modal analysis, and identify the damping values of combination. Finally, the microscopic characteristics of interface was Analysed, and predicted the relationship between damping of the concrete parameters and surface by the finite element method.Through the work mentioned above, the following conclutions can be reached: Firstly, the testing method of this paper and procedure for damping ratio are reliable. Secondly, the damping ratio of the specimen of coarse aggregate, cement mortar and the combination will decline with the increasing of compressive strength in the circumstances of similar frequency.Thirdly, the three-phase material of concrete decrease with increasing of frequency response. Fourthly, transfer function matrix of the beam composite structure that derived in this paper can be used for parameter identification and damping performance prediction. Fifthly, damping parameter of the combination can be identified according to the methods of this paper.Finally, increasing damping value of the combination and reducing the intensity of combination, can be higher than the damping ratio.
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