Application of magneto-rheological dampers to control dynamic response of buildings.

摘要

Earthquakes usually cause huge casualty due to the ground shaking and also due to the failure of built infrastructure such as buildings and bridges. Therefore, it is necessary to control the response of these structures to avoid collapse during earthquake. At present, various control technology is available. Among them semi-active control devices using Magneto-rheological (MR) fluid dampers are promising because of their stability and low power requirement. In this research, performance of three different models of MR dampers, namely RD-1005-3, SD-1000 and MRD-9000 is studied by integrating them into different building structures subjected to different earthquake forces. Here, the dampers and the structures are modeled numerically using the finite element method. It is found that all of the dampers are capable of controlling the response of building frames for different earthquakes. Damper performance is also investigated from the energy point of view. It is found that dampers have the capability of increasing the energy dissipation capacity of a structure without changing the structural properties such as stiffness. It is also found that this type of damper is able to provide some protection even if power supply systems fail during dynamic excitation, which is very common during earthquake. A detailed investigation is carried out to find the optimum location of dampers in simple building frames. It is observed that the performance of the dampers is highly sensitive to the location. Therefore it is very important to investigate the performance of damper before application in a real structure.