Research On The Selection Of Viscous Damper Parameters For Damping Frame Structures

The application of viscous dampers in civil engineering comes from their initial application in vibration control in military and aviation fields.Since viscous dampers were introduced into the civil engineering industry and applied to energy dissipation structures,scholars from all over the world have done a lot of research on the performance and mechanics of viscous dampers.However,the research on how to obtain good energy dissipation and reasonable value of parameters of velocity index‘α’and damping coefficient of viscous‘C_α’damper structure under earthquake action is not perfect.According to the above problem,this paper studies the frame structure in energy dissipation is better when the parameters of viscous dampers‘α’and‘C_α’reasonable range,designed to shock absorption of energy dissipation for viscous damping of the actual engineering design provides a reasonable reference parameter range,expected structure under seismic action has the reasonable damping effect,the energy consumption in different stages of the main components at the same time protect the main structure with balanced seismic performance.In this paper,the response of viscous damping parameters‘α’and‘C_α’to structural related parameters under earthquake is analyzed theoretically,and the relationship between damper parameters and structural related performance is obtained.The relationship between damping ratio and additional damping ratio of single-DOF structures under different characteristic periods‘T_g’and natural vibration periods‘T’is studied by using two methods.It is concluded that when the additional damping ratio of structures is 0≤ζ_cα≤0.1,the increase rate of damping ratio is the largest,and the actual additional damping ratio of energy-absorbing structures is also within this range.When exploring the reasonable range of damper parameters,the research is also based on the range of the maximum additional damping ratio of the growth rate.At the same time,the expressions of additional damping ratio and viscous damping parameters‘α’and‘C_α’were derived by energy equivalence method,and the theoretical calculation results were compared with SAP2000 time history analysis results to verify the correlation law of damper parameters.Finally,the responses of multi-DOF frame structures under different periods under seismic action,such as floor lateral movement,inter-floor displacement Angle,seismic force and additional damping ratio,are studied.The recommended reasonable parameter range of viscous dampers of frame structures is obtained.The reasonable range of velocity indexαis 0.2≤α≤0.5.When the value of velocity index‘α’is within the range of[0.2-0.3],the reasonable range of damping coefficient‘C_α’is between 10000N（s/m）^αand 800000N（s/m）^α.When the value of velocity index‘α’is within the range of[0.3-0.5],The recommended damping coefficient‘C_α’is within the reasonable range of 10000N（s/m）^α-1400000N（s/m）^α.The results show that when the structural parameters of the regular frame are in the above range,which can ensure that the viscous damper has a good damping efficiency in each earthquake stage,and at the same time guarantee the coordinated seismic performance of the main frame structural members.