Incentive Barrier On The Ground Vibration Isolation Performance Analysis And Experimental Research

The isolation measure and analyzing method of ground vibration is an important problem to the field of isolation engineering, because the public environmental problem that brought by ground vibration (including vibrating machines, traffic, construction activities, etc) are increasingly augmenting. In addition, these vibrations bring much trouble to precision instruments, buildings and the life environment of human beings. This thesis deals with the theory of setting barriers in soil to decrease the effect of vibration, and that has been testified by model test and ANSYS finite element analysis.Based on the acoustic wave coincident effect, the theoretical analysis of barrier's coincident effect has been proposed in the thesis by using the analogy of acoustic wave and elastic wave; the calculating formulae and design method of avoiding the coincident effect are also proposed. In addition, the amplificatory phenomenon of dynastic stress at the bottom of barriers has been fully analyzed.The analytical conclusion that in the far-field the surface wave is the chief wave while in the near-field the body waves(including P wave and S wave) are the chief waves is presented, and the conclusion has been validated by finite element analysis of ground wave. SH wave can be used to analyze vibration isolation in both near-field and far-field is proved in the thesis. The theoretical analysis of scatting wave and exporting wave by a single barrier and a row of barriers are also provided in the thesis.Foamy plastic is found to be good isolation vibration material by analyzing wave impedance ratio, and the construct craft of using this material to isolate vibration is also proposed. In the ANSYS analysis of continuous barriers in the far-field, various calculating models under different design condition (including width, thickness of barrier and different barrier material) are presented, and a guide and useful conclusion that can be used to engineering design is obtained by contrastively analyzing of these calculation models.In the model test, the isolation vibration effect of discontinuous barrier underdifferent fashion of force is analyzed. In addition, the effect of export wave by a single barrier and a row of barriers is also discussed in the thesis, and the correctness of test is validated by ANSYS analysis. In the finite element analysis, by setting different parameters of Sp/a, the diameter of pile and the volume of vessel, the various calculation models are presented, and their reasonable design parameters are achieved through contrastively analyzing these models.