Research On Environment Vibration Induced By Bridge Pile Foundation Construction

This dissertation based on the LS-DYNA procedure; simulated the process of the punch holes pile construction; Reappeared the process of the driven hammer to attack the ground with the numerical model. The dissertation discussed the LS-DYNA procedure about the key point of modelling, the rationale and model order. This dissertation made use of the no reflection boundary condition to simulate a limited field, then expressed the derground space or the bulk rock mass. Regarding this kind of question, in order to avoid influence induced by the reflection boundary wave, the no reflection boundary condition is used to the limited field surface to simulate the infinitely great space. The LS-DYNA another characteristic is that defines the contact surface and the control factors of the contact surface. By defining contact, it can be controlled that the driven hammer flushing to the ground and the corresponding contact parameters. This dissertation has served the anticipated analysis purpose with the numerical simulation model.Second, it mainly through exerts a triangle time interval load on the ANSYS model to simulate the function that produced by the driven hammer attacking to ground, then it contrast the result which produced by this triangle time interval load to the LS-DYNA model . At last the dissertation can get relationships between the parameters of the triangle time interval load and the soil elasticity coefficient, so it will provide a basis for the later similar theory's analysis.Third, this dissertation summarized several methods of affected the building by the actual vibration wave. This dissertation focused the influence to the building that be induced by the vibration, it can make use of the characteristic parameter of vibration of the foundation soil (for example, amplitude, frequency, speed and the vibration acceleration of the ground particle) to determine that the rank, the scope and the safe distance to the building. And this dissertation aslo introduced some overseas standards on the controlling of vibration speed and the acceleration.Finally, This dissertation designated the representative pile hole as the experimental object, then carried on the standard punch holes pile impact test, so we can obtain the ground vibration wave dissemination weaken rule by testing vibration signal from different distance piont to the vibration source; we compared these experimental data with the numerical model data, so we can confirm that simulation model is accuracy or not.