Seismic Design And Performance Study Of Viscous Damper Frame Structure

Viscous damping apparatus has a full hysteretic curve,damping performance is superior,small impact on the original structure,repeated utilization high,alternative,and the advantages of restorative sex strong,qing mei and so popular with engineers in high-rise buildings,Bridges,engineering,equipment foundation is widely used in engineering,such as great power "toughness" in urban and rural areas in China.However,in present structural design,engineers usually design viscous dampers by repeated trial calculation based on engineering experience,resulting in low design efficiency and redundant workload.The connection form and arrangement of viscous dampers still have a significant impact on the damping and energy dissipation performance of the whole structure,and further systematic research is needed.Based on the above problems,this thesis uses ETABS finite element software to study the damping design and performance of viscous damper frame structure.The main research contents and conclusions are as follows:（1）The concept and principle of energy dissipation technology,the development of viscous dampers,the restoring force model,the design and analysis method of energy dissipation structure and the calculation method of additional damping ratio are systematically summarized.According to the existing damping design method,a damping design method based on base shear reduction rate is proposed.Taking a cultural and creative industry center project in Hainan Province as an example,the damping design scheme is determined,and the elastic time history analysis of frequent earthquakes and the elastic-plastic analysis of rare earthquakes are carried out.The results show that by controlling the base shear reduction rate of the structure by 20 % to determine the damping scheme of the viscous damper,the seismic performance of the structure under rare earthquakes can be ensured to meet the specification requirements,and at the same time,it has a certain safety reserve.The design method and analysis method proposed in this thesis can provide a quantifiable index for the design and research of the energy dissipation and damping of the viscous damper with a base shear reduction of 20 %.（2）Based on a practical engineering example,the effects of cable connection,scissor connection,wall connection,miter connection and diagonal connection on the damping and energy dissipation performance of viscous dampers are studied.The results show that the viscous damper connected by lasso provides the largest additional damping ratio of 16.57%,dissipates the most seismic input energy,and minimizes the displacement Angle between layers.The diagonally connected viscous damper provides the lowest additional damping ratio of 4.95%,the worst energy dissipation capacity,and the largest inter-storey displacement Angle.In the same working condition,the damping and energy dissipation performance from strong to weak are lasso connection,scissor connection,wall connection,miter connection and diagonal connection respectively.Therefore,in order to improve the economy of shock absorption project,viscous damper cable connection can be preferred.（3）Based on the finite element model of reinforced concrete frame structure with column spacing of 8000 mm,the variation of additional damping ratio of the structure was studied when the position of the connecting wall of viscous dampers changed from column end to mid-span,and the damping performance of the connecting wall at different positions in mid-span was investigated.The results show that when the connecting wall is located in the span of the beam,the viscous damper provides the maximum additional damping ratio of8.54%.When the connecting wall is located at the end of the beam,the viscous damper provides the minimum additional damping ratio of 4.32%.Therefore,viscous dampers should be placed in the middle of the span of the structure in practical engineering.