Performance Analysis Of Reinforced Concrete During Construction Period In Building Structure

Research on reinforced concrete structures’ construction period has been drawnmore and more attention. With the development of the construction industry, theconstruction phase in the whole life length raises a lot more attention than before on theaccount of the fact that the structural forms of houses at present become more and morecomplicated with their height being higher and higher, leading to a greater difficulty forconstruction.A detailed analysis for reinforced concrete structures’ performance duringconstruction has been made in this thesis. And its basis lies in the principles of howconcrete’s various behaviors change with time, especially concrete’s compressionstrength, elastic modulus, strain-stress relationship and creep, which provide thetheoretical foundation for the construction simulation in this thesis.During the period of construction, the main structure and the formwork supportbuilding up temporary stress system. Full-house scaffolding and support frames are twotype which are widely adopted in engineering. In this thesis, their internal forcetransmission path and calculation method together with failure mode have beenanalyzed. Fastener node is a half-rigid node, full of the fastener node in addition towhole scaffold outside force, or vertical load of the key parts of the transmission,indicating that fastening is crucial.The structure during construction is influenced by theinteraction of scaffolding supporting system and structure itself. And this interactioncould be affected by numerous factors greatly, such as concrete’s age, the rigidity offramework supporting system and foundation, the thickness of slabs, boundaryconditions of the floors during construction, column spacing, concrete placement andtemperature difference between day and light etc.For simulation for construction phase with Sap2000, first of all, CEB-FIP(90) isemployed for determining material behaviors. Then performance analysis duringconstruction has been undertaken using the unique stage construction modules, whichcan be divided into three main aspects:1to analyze the mechanical and deformationperformance of reinforced concrete structures during construction;2to compare andanalyze performances under different construction cycles;3to compare the influenceswith and without considering construction period.Analytical results demonstrate that the characteristics that concrete’s early age during construction and geometric model vary with time would have a adverse effect onstructures. In the different construction period, beams and columns internal forcedifference, but the difference of column stress is small, even if the stress of the beamare quite different, the relative value is small, therefore, the internal force of the beamand column can not be the control function. For board, different cycle greatly differentdeformation, so, we should pay more attention to board.The result of don’t considerstage construction is bigger than consider stage construction. The biggest percentagepoints to75%.Therefore, it is necessary to analyze the reinforce concrete structures’performance during construction before built in order to avoid blind spots in structuraldesign and construction design.