| Prestress assembling concrete structure have higher performances than other concrete structure forms, possessing the advantages of pretressed concrete and assemble concrete being characteristic of safe, economy, high production rate, assurance of quality, reducing environmental disturbance and contributing to sustainable development, according with the development direction in the future, etc. Based on the studies at home and abroad, experimental and theoretical studies on the seismic performances of pretress assembling concrete beam-column connections added passive energy dissipation device are carried out here in order to improve the ability of energy dissipation and reduce seismic responses. The main research contents as follows:(1) An invention of new lead damper. On the basis of intensive analysis of technical performance and application scope of existing dampers, a new lead damper of displacement-amplifying type is developed with characteristics of high efficiency of energy dissipation, stable performance, good durability, little space occupation, etc.(2) Theoretical and experimental studies on the damper which is developed in this paper are carried out. Finite element method and periodic dynamic testing method are used to analyze the influencing factors for the damper, such as length, width, height of lead block and amplitude, frequency of load, etc. The results show that the rolling type lead shear damper realizes the preconcerted aim of better energy dissipation capability on the condition of small displacement. The hysteretic curve was chubby and the approximate parallelogram distribution characteristics. The restoring force model of the damper is been suggested on characteristics of restoring force. The damper is characterized by simple process, lower cost, small area. The lead shear damper is suitable for vibration control of building structures.(3) Theoretical and experimental studies on the behavior of prestress assembling concrete beam-column connections added passive energy dissipation devices and without them are carried out. By finite element method and experimental research, the performance and parameters of beam-column connections added energy dissipation device is investigated. The parameters include magnitude of prestress, location of prestressing tendon, form of reinforcement in the end region of beam and different yield forces of damper. Stress distribution, failure mode, hysteresis characteristics, deforming capacity, cracks development, energy dissipation and stiffness degradation are studied. The research results show that the energy dissipation capacity of joint added energy dissipation device is improved greatly and that is proved that the damper proposed in this paper maintains a good energy dissipation property, stable performance, and makes up for the weaknesses of low energy dissipation ability of prestress assembling concrete structure, provide essential technical conditions for its application in earthquake area. The structure added damper increase its carrying capacity, influence the ductility less. The failure mode of prestress assembling concrete structure added this damper is still"beam end plastic hinge failure mechanism". This failure mode is beneficial to stress distribution with minimum damage, and structural repair.(4) A new energy dissipating device is proposed in this paper, which is characterized by doing no take up service space, forming one body with structure so that the problem of existing energy dissipating device occupying large service space is solved. By finite element method frame joints and frame structure added this energy dissipating device is investigated in several case. The results show that vibration energy dissipation ability of is notable, do not take up extra space, and do not need the maintenance in the future.
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