The new structure after adding stories is often composed of existing reinforced concrete structure or brick structure and steel structure.Aseismic calculation of such structures should be based on undivided model.The damping characteristics are different between the several parts,so it is less accurate to use a uniform modal damping ratio.A practical method for calculating the modal damping ratio is studied.In order to consider the high-order modal response of the new added structure,the calculation method of the effective mass coefficient of part structure is introduced.Finally,the dynamic interaction between the added structure and the existing structure is discussed,and the reason for the decrease of the base shear force is proposed.The above methods have been added to the PKPM,which is a software system for structure design,to improving the accuracy of aseismic calculation.
关键词
既有结构/加层/阻尼比/有效质量系数
Key words
existing structure/adding story/damping ratio/effective mass coefficient
维普
万方数据