Shaking Table Tests Of P-TMD In Building Structure

As one of passive control technology,the tuned mass damper(TMD)is constantly used in the construction of buildings.Though its advantages are far beyond counting,it also contains many disadvantages that can be easily recognized.Firstly,TMD is sensitive to the frequency,which means its damping effect can reach its best only when the frequency of TMD is close to that of the main structure.However the frequency of high-rise buildings will undergo certain change because the live load and stiffness of high-rise building are different in real environment.The result is that it is very hard to predict the damping effect of TMD.Compared with frequency band of the earthquake,the effective frequency band of TMD control is narrower.Therefore most of TMD are used in wind-induce vibration.Secondly,hundreds of thousands tons of mass element of TMD is set on the main structure,which has a great impact on its dynamic response.When the limit system is damaged in the wind or earthquake excitation,it will make a great loss.Furthermore,The TMD occupies a lot of space and it is not easy to be installed.The unique high power damper needed is also very expensive.As the pounding tuned mass damper(P-TMD)is a new type of dampers,its element mass collides with limitation device.The collision happening between the mass block and viscoelastic materials will further consume energy through the deformation of viscoelastic materials.this paper attempts to apply P-TMD to frame structure in the field of vibration reduction..The thesis has launched the following research:1.Based on the previous research,the force mode of P-TMD is proposed.Numerical simulation on a three-story frame structure is conducted by ANSYS and MATLAB software.The response of structure under different conditions is analysed,including uncontrolled,TMD controlled and PTMD controlled.It indicates that the control effect of PTMD is better than TMD under Tianjin and El Centro excitation.Parameter study is then conducted.Results show that mass ratio has a little effect on control effect.The effect of P-TMD is more sensitive to the value of gap.2.In order to verify the effectiveness of P-TMD,a three layer aluminum frame structure is designed to make shaking table test of P-TMD in building structure.The device of P-TMD is also designed.Different seismic excitation and loading condition are adopted according to the structure of the models.Stain gauging points are used to analyze the change of structure under different conditions.Results show that P-TMD has a better performance than TMD under different excitation.The effect is more evident with the increase intensity of excitation.Besides,the relatively stable effectiveness can be obtained by different the gap.