Bending Rigidity And Capacity Of Frame Beams With Monlithical RC Slab In Consideration

The earthquake occurred at a disadvantage. The harrowing experiences were given in the earthquake. To ensure the spatial frame structure of the seismic fortification of No Collapse in the strong earthquake, a philosophy of Strong Column Weak beam is recommended in the current codes. However, in the structural design process, practical factors are not considered fully, which results in Strong beam Weak Column in a large number of structures. One chief factor of this phenomenon is that slabs improve frame beam rigidity and bearing capacity.To determine the effect of the slab toward the frame beam rigidity and bearing capacity under the vertical load, finite element analysis software ANSYS is used and the nonlinear models are adopted in this paper based on the previous study, which get the rigidity and bearing capacity amplification coefficient. The main contents and conclusions in this paper are listed as follows:1. The crack trend of development is researched under the vertical and distributed load. The results indicate that the first crack occurred at the bearer; 2. The effect of the slab toward the frame beam rigidity is researched. The results indicate that the rigidity amplification coefficient of middle beam stiffness is 2.441, and that of middle beam stiffness is 1.721.3. The tensile and compressive reinforcement stress is researched at the bearer. The results indicate that the slab reinforcement can resist hogging moment on the edge of beams and put off the time of plastic hinges forming at the edge of beam. Meanwhile, the increasing of the slab width can decrease compressive reinforcement stress at the frame beam.4. The reinforcement stress in slabs is researched. The results indicate that, under the working load:(1)the slab reinforcement participation extent decreases with the increase of distance towards beam; (2)the number of participation reinforcement increase with the increase of the width of flange;(3) the slab reinforcement participation extent at top surface is higher than that at lower surface. At the yielding and limit point, reinforcement stress in slabs disobeys any rules.5. The bearing capacity of beam is researched. The results indicate that, when the effective flange widths of middle beams are between 4 and 6 times thicker slab and that of edge beams are between 3 and 5 times thicker slab, the bearing capacity of beam increases obviously. The capacity amplification coefficient of the slab toward middle beams is 1.33, and that of the slab toward edge beams is 1.17.In the end, the paper concludes the research and points out problems to be further studied.