Research On Seismic Performance Of Bolted End-plate Joints For Prefabricated Prestressed Concrete Beams With High-strength Reinforced Concrete Columns

In recent years, with the rapid development of the prefabricated concrete structures in China, the building and residential industrialization also become a interested topic, and the reform and innovation about industrialization method is the trend for the development of the construction industry. This will greatly improve the labor productivity and save the social resources. In the prefabricated frame structure,the beam-column joints are important transmission components, and its seismic performance and integrity of structure is important to the safe use, at the same time, the difficulty of the joints in the construction site also determines the degree of popularization and application about the form of the joints. This paper introduces the end plate bolt joints commonly used in steel structure into the concrete structure, using the high strength bolt to connect the end plate and concrete column with steel plate hoop together.The longitudinal reinforcement of the beam is weld on the end plate in the form of the pier head,and anchorage nut bearing pressure provides the pressure of the beams, thus a new form of assembling joints is formed. In this paper, on the basis of the traditional prefabricated joints, a thorough test and theory research about the mechanical performance of this new form of joints is discussed.In this paper six prefabricated prestressed fabricated intermediate joints specimens and a cast-in-situ specimen as a contrast are designed. The test is accomplished under the low reversed cyclic horizontal load. Its working mechanism,the shear bearing capacity and the bending bearing capacity are analysed, at the same time the strength and stiffness degradation of specimen, the capacity of ductility and energy dissipation are analyzed.Studies have shown that under the low reversed cyclic loading the load- displacement hysteresis curve of the prefabricated prestressed fabricated intermediate joints has good stability, and it is more substantial; The good ductility,energy dissipation capacity and seismic performance are demonstrated reasonably.In this article, on the basis of the results of the study about the prefabricated prestressed fabricated joints under the low reversed cyclic load, three linear restoring force model is established.The calculation formula and hysteretic rule of the corresponding phase are given, and loading and unloading stiffness with the rule of variation of amplitude increase of displacement is analyzed. According to the comparison of the test and the calculation results, the conclusion is good. The proposed restoring force model can reflect the characteristics of stress and deformation of the end plate bolt connection joints in the earthquake, and the results can provide the reference for prefabricated structure about the elastic-plastic seismic reaction analysis.