Research On The Vertical Mechanical Behavior Of New Type Assembly Continuous Span Floor Slab

With the development of social economy,the load of industrial and civilian electricity is increasing gradually,and the speed and quantity of substation construction are increasing gradually.However,most of these constructions adopt the traditional construction mode,which has the shortcomings of high labor intensity,slow construction speed,low production efficiency,long construction cycle,large environmental pollution,more material consumption and difficult quality control.The assembled steel structure has the advantages of light weight,good seismic performance,high material reuse rate,fast construction progress and easy repairing.At present,the supporting slabs of steel structure buildings mainly include profiled steel composite slabs,steel truss slabs and prefabricated SP slabs.Although assembling can be realized,the construction technology is too complicated.Based on the requirement of rapid assembly of substation projects,this paper presents a new type of beam-slab connection and slab-slab connection,"a new type of high-strength bolt connector",and carries out experimental research and finite element simulation analysis on the vertical mechanical properties of different forms of floor.(1)Vertical loading tests were carried out on fully prefabricated RC slabs,common concrete composite slabs and reinforced truss concrete composite slabs respectively,and the vertical loading performance of new type of assembled continuous span slabs was studied comprehensively.The analysis results show that the new floor has high bearing capacity,the reinforced truss concrete composite slab has the highest bearing capacity and stiffness,followed by the fully prefabricated RC slab,the ordinary concrete composite slab has the lowest bearing capacity and the lowest stiffness,but the bearing capacity of the three specimens is almost the same when the normal deflection is satisfied;during the whole loading process,the new beam-slab connection in the new floor Joints and slab-to-slab connections show good force transfer performance,which indicates that the connection structure of the new type floor achieves the expected effect;the force of the new type assembly continuous span floor is different from that of the simple supported floor,and the internal force will be redistributed.The stress and strain at the negative bending moment above the middle steel beam develop faster than that at the midspan and loading point,and the stress is larger,and cracks will appear first in the three new type assembly continuous span.The cracking deflection of floor slabs is less than the allowable value of deflection,which meets the requirements of service stage and has high safety.(2)ABAQUS,a non-linear finite element software,is used to simulate the new type of assembled continuous span floor.The results of finite element calculation are in good agreement with the experimental results of the new type of assembled continuous span floor,which proves the feasibility of the modeling method.The stress and strain distribution law of concrete,steel bar,steel beam,new connecting steel plate and new high-strength bolt connector,as well as the formation and development of cracks in the whole loading process of the new type of assembled continuous span floor slab are analyzed.On this basis,the influence of relevant parameters on load-displacement curves of new type assembled continuous span slabs is analyzed by finite element simulation,so as to further understand the vertical mechanical properties of new type assembled continuous span slabs.Finally,the paper summarizes the research,and puts forward the existing problems and suggestions for future research.