The Hysteretic Performance Study On The Wallboard Joints Of Composite Floor Slabs With Reinforcement Inside On Four Sides

The traditional stressed reinforcement at the bottom of prefabricated floor was designed to extend into the connection joint of the composite floor slabs and the shear wall or beam with the disadvantages of inconvenience of transport and construction to ensure the seismic performance.As the new type of connection joint,composite floor slabs with stressed reinforcement inside on four sides is given in the standard drawings.The holes in the template are not reserved in the composite floor slabs with stressed reinforcement inside on four sides,which reduces the difficulty of processing and solves the bending and rusting problem of reinforcement at the bottom of prefabricated floor during the process of transportation and stack.The research and extension of the joint at the bottom of the composite floor slabs with reinforcement inside on four sides conforms to the principle of sustainable development.The seismic performance should be studied in order to promote the application of the new composite floor slabs with reinforcement inside on four sides in earthquake resistant areas.In this paper,six groups of wallboard joints of composite floor slabs with reinforcement inside,one set of wallboard joints of composite floor slabs with reinforcement outside and one set of cast-in-place wallboard joints were designed and fabricated and the low-cycle reciprocating loading tests were carried out for each.The seismic performance indexes such as energy dissipation capacity and ductility of each group of wallboard joints were compared and analyzed to analyze and evaluate the seismic performance of the new wallboard joints of the composite floor slabs with reinforcement inside.The main research work carried out is as follows:1.The influence study of additional reinforcement length on the seismic performance of the wallboard joints of composite floor slabs with reinforcement inside on four sidesThe wallboard joints control groups including long additional reinforcement,conventional additional reinforcement and short additional reinforcement were set.The length inside the joint area of the long additional reinforcement is the same as that of the conventional additional reinforcement and the length inside the composite floor slabs of the conventional additional reinforcement is the same as the short additional reinforcement.The hysteretic behavior of three groups of wallboard joints were compared and analyzed to inquiry the influence of additional reinforcement length inside the joint area and inside the composite floor slabs on the seismic performance of the wallboard joints.The experimental results show that the seismic performance of wallboard joins is better with the longer additional reinforcement length inside the joint area and the effect of the additional reinforcement on the seismic performance of the wallboard joints is not significant.2.The influence study of additional reinforcement arrangement on the seismic performance of the wallboard joints of composite floor slabs with reinforcement inside on four sidesThe wallboard joints control groups including long additional reinforcement in the groove of prefabricated floor,long additional reinforcement,short additional reinforcement in the groove of prefabricated floor and short additional reinforcement were carried out.The hysteretic behavior of four groups of wallboard joints were compared and analyzed to inquiry the influence of additional reinforcement arrangement on the seismic performance of the wallboard joints.The experimental results show that the bearing capacity,energy dissipation capacity and ductility of the long additional reinforcement in the groove are significantly improved and the effect of the short additional reinforcement in the groove on the seismic performance of the wallboard joints is not significant.3.The comparative study on the seismic performance of the wallboard joints of composite floor slabs with reinforcement inside,the wallboard joints of composite floor slabs with reinforcement outside and cast-in-place wallboard jointsThe hysteretic performance of the wallboard joints with long additional reinforcement in the groove,composite floor slabs of non-additional reinforcement with the stressed reinforcement inside,composite floor slabs of non-additional reinforcement with the stressed reinforcement outside and cast-in-place wallboard joints were compared and analyzed to evaluate the seismic performance of new wallboard joints of composite floor slabs with the stressed reinforcement inside based on the preliminary comparative study.The results show that the energy dissipation capacity of wallboard joints with long additional reinforcement in the groove is the highest,the bearing capacity is higher,the deformation capacity is the strongest,the ductility is better and the seismic performance is the best.