The Internal Force Calculations Research Of The Joist For Frame-supported Multi-ribbed Composite Wall Structure Under Vertical Load

Multi-Ribbed slab structural system which with tree parts of pre-ribbed composite wall, invisible frame and cast-in-place reinforced concrete floor, is a lightweight, high strength, energy saving, a new seismic building structure system. Frame supported multi-ribbed slab structure that composed of the bottom frame-shear wall structure and the upper slab is quite suitable for the large bottom space buildings. As one of the most important component, the multi-ribbed wall beam is made of the reinforced concrete frame in the bottom and multi-ribbed composite wall in the upper. As a new structure system, Wall-beam structures are very complex; it contents composite performances and other problems. Moreover, the mechanism and calculation research of the structure needs further study.Based on the former research, this paper emphasizes on the force characteristic of the frame supported multi-ribbed composite wall-beam under vertical load through two ways that theoretical analysis and numerical simulation, and does a more in-depth study and discussion for the internal force calculations method of joist. The main research contents are summarized as follows:1,Presents bearing mechanism, joist's mechanical characteristics, calculations for variety of wall-beam structures under vertical load.Base on previous study in and abroad, this paper mainly introduces the bearing mechanism, the joist's mechanical characteristics, the calculations for wall-beam structures under vertical load.2,Through the nonlinear FEM analysis under vertical loads, the bearing mechanism, the bearing capacity and their influents of the frame supported multi-ribbed composite wall-beam are revealed.Base on the validated numerical model, this paper does a mechanical analysis on single-span, double-span of the frame-supported multi-ribbed composite wall-beam with or without holes under vertical load. And moreover, an extensive parametric study is conducted to analyze on bearing capacity effects of multi-ribbed composite wall-beam under the action of high-span ratio, hole size, hole location, joist spans, joist height and longitudinal, reinforcement rates.3,Base on the structure's characteristics, the simplified mechanical model was proposed for frame-supported multi-ribbed composite wall beam. With the combination activity of wall-beam structure, the internal force of joist was calculated with the method of beam on the elastic foundation which takes the horizontal friction resistance into considerationBase on the structure's characteristics, multi-ribbed composite wall could be equivalent to composite materials effective elastic plate that at the base of light block, concrete rib beams, ribs, reinforced fiber frame. With the combination activity of wall-beam structure, the simplified mechanical model was proposed for frame-supported multi-ribbed composite wall beam. And the internal force of joist was calculated with the method of beam on the elastic foundation which takes the horizontal friction resistance into consideration. And moreover, provides a theoretical basis.