Experimental Study On Assembled Monolithic Reinforced Concrete Box Floor System

The assembled monolithic box floor researched in this paper is a new kind large span floor by improving the traditional hollow floor, it is made up of by three parts: hollow box, cast-in-site ribs and laminated layer. The hollow box is prefabricated and produced by manufacturer, the bottom of the hollow box can work as bottom die, the side face of the hollow box can work as side form, this only requires underpining the bottom die under the ribs, cast-in-site ribs and laminated layer concrete, which saves up lots of formworks and reduces the mount of the cast-in-site concrete, also cuts down the cost of project and shortens the time of the project. This way makes hollow floor light weight, cost cheap, simple construction, it is suitable to popularize and apply in large span, large bay buildings.This paper makes experimental study and finite element analysis to the assembled monolithic box floor. The test results show that the assembled monolithic box floor has good integration and has the characteristics of high stiffness, high bearing capacity etc. the paper has six parts:The first chapter introducts the application status of large span floor, and introducts structural form, performance,construction technology of the assembled monolithic box floor.The second chapter researches the feasibility of structural measures of box bottom connection in the assembled monolithic box floor with the lap performance test to seven small slabs.The third chapter obtains the load-displacement curve, fracture distribution of test model through static loading test to one-way simply supported plate belt of the assembled monolithic box floor, the span length is 7.2 m. It shows that this floor bottom plate is involved in force enough and has good integration.The fourth chapter makes nonlinear analysis under the vertical load to the assembled monolithic box floor with finite element software ANSYS analyzing test model. the calculated load-displacement curve is in good agreement with test results. It shows that the reinforced concrete nonlinear finite element analysis theory in the calculation is correct, finite element analysis program is reliable.The fifth chapter analyze the simply supported bidirectional slab model of the assembled monolithic box floor with finite element software ANSYS, and compair internal forces, deflection etc calculation results with the same size of ribbed floor finite element model and solid-slab floor finite element model. It proved box floor is a special"slabs"structure, and show that the assembled monolithic box floor has good stiffness and performance relative to other floor forms.The sixth chapter puts forward feasible conclusion to engineering application of the assembled monolithic box floor, and proposes the next research direction of this floor.