| As a new type of building structure, hybrid structure has already used in many buildings around the world. But there are still existed a few problems in practical application. Research on steel reinforced concrete at home and abroad mainly concentrated on the seismic behavior of steel reinforced concrete beam-column joint, the seismic performance of the steel reinforced concrete frame structure, the performance of steel reinforced concrete resists to fire. There are few research on simplifying the steel reinforced concrete node design and putting forward a new structure form in order to simplify the construction process. In addition, there are no accurate conclusions on the shear performance of steel reinforced concrete beam-column joints. The existing design of steel reinforced concrete beam-column joints in China is still digging a hole in the steel beam-column web in order to place stirrup, The method not only difficult construction, but also weak the web of steel, and has an adverse influence on the bearing capacity of the node.This article refers to the existing form construction of steel reinforced concrete beam colum n joint, combining with the theory of shear capcity suitable for steel reinforced concrete beam co lumn joint in domestic and abroad fields and finally designs a new joint form with partitions in th e core zone of joint(SRCJ-1).In order to prove the validity of the joint and study the seismic performance, we design a traditional form of steel reinforced concrete beam column joint(SRCJ-2) and a joint form without stirrup in the core zone(SRCJ-3).We finally use the three types of steel reinforced concrete beam column joint under low-cycle reciprocating load to make this experiment. These test specimen all designed by the rule of "strong beam and weak column joint", we using them to get the rule of crack propagation and distribution, the percussive load displacement curve and the main strain component. According to the test result, we get the failure mechanism of the structure, the percussive skeleton curves, the yield load and ultimate load, the displacement ductility coefficient and energy dissipation performance, the intensity attenuation curve and stiffness degradation curve and the main rule of the stain for the core zone of joint. Through the analysis of the content, we get the following conclusion:All forms of component damage are core shear destruction which match with design purpose; Yield load, ultimate load and seismic performance of SRCJ-2 and SRCJ-3 are the same basically, SRCJ-1 was lower; Intensity attenuation and the stiffness degradation trends of SRCJ-2 and SRCJ-3 are in good agreement with each other, SRCJ-1 can be consistent with the former two earlier, later reduced rapidly. The shear bearing capacity of steel reinforced concrete research shows that: Shear bearing capacity of steel reinforced concrete beam-column joints is mainly provided by the concrete, the shear capacity of concrete oblique compression bar accounts for about 80% of the total capacity, steel shear capacity accounts for about 15% of the total capacity, the shear capacity of stirrup accounted for only 5% of the total carrying capacity; Shear bearing capacity of SRCJ-2 lower than SRCJ-3's by 10%, proving the partition can effectively confined concrete; Suggested that the shear bearing capacity of the joint core calculation does not consider the effect of stirrup part, and this part can regard as the shear bearing capacity of safety stock.The research results to put forward reasonable stress, is advantageous for the construction of the new type of beam-column node form provides experimental data and theoretical basis, not only make construction process is simplified, still make the construction quality guaranteed... |
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