| Prefabricated buildings is the only way of building industrialization, and the effective way to resolve the contradiction between economic development and environmental protection. Traditional prefabricated building has poorer seismic performance than cast-in-situ concrete structure, and require construction technology with high quality, and isn't fully assembled building of which all the component are precast in factory. Three shortcomings seriously hampered the development of prefabricated buildings. The seismic performance is closely related to structural integrity which depends on the connection performance among components, while for most of the structure, especially the frame structure, beam-column connection joint performance determines the seismic performance of the whole structure. Therefore research on the fully fabricated concrete structure of which seismic performance is improved by improving beam-column connection capacity possess significant values of scientific research and practical as well as can conquer the difficulties on the road to building industrialization.In this paper, 11 specimens were designed in total based on the design principle that is the end plate bolt connection, bidirectional prestressed reinforcement method and arranging densely high strength hoops for shear, including one cast-in-situ concrete joint, six prefabricated concrete column-beam joints and four steel beam and reinforced concrete column joints. This paper completed the following work based on low reversed cyclic circulation pseudo-static test on those beam-column joints.Through laboratory study, it is shown that the hysteresis curve of the fabricated joint pinched slightly with the opposite S-shaped due to the effect of bidirectional prestressed and strong displacement restoring capacity. But from the overall, the area inside the hysteresis curve was so full that the energy dissipation ability is good. The end region of beam appeared plastic hinge and then bending failure, which conformed the seismic concept design that requires the strong joints, major shear and minor flexure.Compared with Eurocode 3: Design of steel structures, cast-in-situ joint as the rigid joint representative, the experimental data shown that joint classification of EC3 does not apply to fabricated structure and suggests that new type of prefabricated joints can be considered as rigid joint in the general engineering design. At the same time, it was found that joint classification of EC3 does not apply to fabricated structure the due to the steel column flange occur deformation more easily than the concrete column section. But this classification method is worthy of reference, the fabricated structure joints classification based on EC3 was proposed, which can provide a reference for prefabricated structure engineering design. By Comparing with the joints using steel bar to connect the end plate on both sides of column and the others with no measures, it was found that the initial rotational stiffness of the connection is greatly influenced by the strength of the connection type, which suggest that the essence of that the linear stiffness of beam effect on the initial rotational stiffness of the connection is that the change of shear force has influence on the rotational stiffness.Through the analysis of high-strength hoops strain, it was shown that the dense arranged high strength hoops has so strong restriction effect on concrete that concrete is under the three-dimensional pressure, which can improve the strength and ductility of concrete as well as indirectly increase the diagonal shear strength of web, as result that the restriction on the size of section bearing shear is lower. |
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