Framework Structure Internal Force To Consider The Finite Element Analysis Of Floor Stiffness Change Impacts

In this thesis, the power of ANSYS is used to make a Finite Element Analysis to the reinforced concrete frame to considerate the floor stiffness changes, then compared it to the results of PKPM to make a research for structural design consideration. The completions of major tasks in this thesis are as follows:1,Cast-in-placeconcrete as the beam flange increase the effective stiffness of the floor beams, In structure design we usually taking a stiffness magnification factor to consider this impact, but how to take the stiffness magnification factor to the beam, there is not a fixed reference value. In this article, by using the software of ANSYS to make a Finite Element Analysis to the reinforced concrete frame and compare it to the results of PKPM firstly, then fit the formula of stiffness magnification factor to provide some reference to the design.2,In this paper, the author discussed the rigid floor assumption by using the method of finite element analysis, and investigate the change of floor stiffness on the impact of the internal force from the following three aspects, and give proposals to how to correct the internal forces.(1) the change of thicknessThe author made a finite element analysis when the thickness changes in the 80-200mm and compared it with the results of PKPM on assumption of rigid floor, obtained that the internal force is too small when the thickness changes in the 80-140mm. Therefore, the designer should increase the shear and moment to each column on border region.(2) the change of aspect ratioThe author made a finite element analysis when the aspect ratio changes and compared it with the results of PKPM on assumption of rigid floor, obtained that the internal force is too small when the aspect ratio changes. Therefore, the designer should increase the shear and moment to each column on border region.(3) opening for floorThe author made a finite element analysis with middle and border openings respectively and compared it with the results of PKPM on assumption of rigid floor, obtained that the internal force of the column which around the hole is too small. Therefore, the designer should increase the shear and moment to each column that around the hole.