| At present,prefabricated concrete structure,which is widely used in the field of construction industry,is becoming increasingly popular because of its high efficiency,energy saving,safety,low carbon and so on.Among them,the structural form of joints is the key to the seismic performance of structures.Referring to a large number of domestic and foreign literature,it is found that the current research on the seismic performance of shear wall-floor slab joints focuses on in-plane seismic performance,while the research on the out of plane seismic performance of cantilever slabs is relatively lacking.Therefore,this paper introduces the manufacturing of one cast-in-situ shear wall-floor slab joint specimen and one superposed shear wall-floor slab joint specimen referring to domestic and foreign literature,analysing the seismic performance of joint specimens under the vertical seismic force at the end of the floor by experiments and finite element simulation,which provides a reference for promoting the development and application of prefabricated building structures.Designing and manufacturing the cast-in-situ shear wall-floor slab joint specimens and the superposed shear wall-floor slab joint specimens.Obtaining the yield load of the specimens by theoretical calculating,formulating the loading scheme,which conducts the designing and manufacturing of the loading aids.Exploring the seismic performance of the specimen by analysing on the damage,hysteretic curve,skeleton curve and stiffness degradation curve,displacement ductility and energy dissipation capacity of the joint specimen after quasi-static test conducted by the servo loading system.Numerical simulation of the same sized model is analyzed based on the plastic damage model of concrete of ABAQUS,and the establishment process of the model and the selection of material constitutive model are described in detail.Demonstrating the correctness of various parameter settings during numerical simulation by comparing the numerical simulation results with the experimental results,the following findings are made:1.The crack distribution and extension of the superposed specimen in the cast-in-situ layer are basically consistent with the corresponding surface of the cast-in-situ specimen,while which in the superposed layer is less than the corresponding surface of the cast-in-situ specimen.The mechanical performance of the superposed specimen when the prefabricated floor slab is compressed is basically the same as that of the cast-in-place specimen,while worse in the reverse stress,due to the separation of the prefabricated floor slab from the wall,the prefabricated layer does not participate in the tension,so there are fewer cracks on the prefabricated layer.The hysteretic curve of cast-in-situ specimens is relatively full,while the superposed specimens have obvious pinch phenomenon and poor energy consumption capacity;2.In this paper,the reinforcement structure was designed based on the existing specifications,pointing out the defect of considering the mechanical performance under unidirectional load only and lacking in anchorage between the prefabricated floor and the wall this kind structure,which results a lower seismic performance of superposed specimen comparing with the cast-in-situ specimens of the same size.So this kind of structure should not be used at the shear wall-floor slab joint where seismic resistance needs to be considered in practical engineering;3.The results of numerical simulation are basically consistent with the experiment.The error of yield load,peak load and ultimate load obtained between FEM and experiment is less than 10%,which shows that the setting of various parameters during numerical simulation is referential partly. |
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