| With development of the national economy and the improvement of the people's living standards, contributed to the sixth large-scale speed-up in the nationwide railway which would increase the speed of trains and induce the emergence of the heavy-load railway. The environmental vibration problem induced by rail transit has become increasingly serious which has a serious effect on the living standards of peoples, the safety of building stuctures and the normal performance of precise instruments and high-tech facilities. The building vibration problem induced by rail transit has been one of the most significant study.In this dissertation, the prediction of building vibration and the parameters of influence induced by train are studied. The model of train-track-soil-interface-building system is established based on the dynamic interaction influence of soil-building foundation. In the model, the formula of vibration prediction is presented under different contact conditons. Then, the vibration laws are studied with different measures for vibration reduction. The main contents include:(1) Based on the dynamic soil-structure interaction, there are three different contact modes, namely, distortion coordination, elastic contact and nonlinear contact, between soil and building foundation. The characteristics on vibration induced by train have been analyzed based on building, interface and soil under the three contact modes respectively.(2) The vibration analysis model induced by train is established under the three contact modes. The analysis model includes two parts, one is the vibration source model for train-track system from which the driving forces of vibration source can be acquired; the other is the soil-interface-building three-dimensional finite element model from which the vibration responses induced by trains can be attained. In the analysis model, a lot of factors are considered which have influences on building vibration such as track irregularity, train speed, distance between train and building, property of foundation soil, vehicle type and building height.(3) Based on the analysis model, the building vibration can be calculated according to the influencing factors under different contact conditions. The quantitative analysis on influence characteristics of every factor can be attained by statistical analysis. The prediction formula of building vibration induced by train can be regressed under the three contact conditions. The applicability and accuracy of different prediction formula are compare with the site experiment, which shows that the prediction formula considering nonlinear contact between soil-building has a stronger applicability and accuracy. (4) The data from in-situ experiment of a six-storey building alongside the Beijing-Guangzhou railway are used to analyze the effects of train-induced vibrations. The results show that vibrations of the building alongside the rail are related with a lot of factors, such as train speed, vehicle type and the distance between train and building.(5) The spatial dynamic analysis model for building is performed to analyze the dynamic responses of building induced by train under distortion coordination mode and nonlinear contact mode, respectively. Then the results from the models are compared with the ones from in-situ test. The results showed that the model under nonlinear contact model is better than the coordination model.(6) Numerical analysis is adopted to analyze the effects of building vibration reduction with different isolating vibration measures, such as isolation trench, insolation wall, insolation foundation, the dynamic property adjustment of building, and secondary-isolation structure on the floor. The numerical results show that the building vibration induced by train belongs to micro-vibration, and the isolation effects of isolation trench, floor mass change and insolation foundation are more effective than other isolation vibration measures.
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