Research Of Force Performance And Design Theory Of The New Large Column Grid Prestressed Concrete Curb Beam Structure

This paper presents a new type of prestressed grid beam structure in the conventional structure of the beam-column joints instead " riding axis" type column caps node. The floor has been strengthened by the greatest force of the beam-column joints area. This approach has two distinct advantages:the material used in the site of the largest force,makes the material utilization efficiency high, saving resources; prestressing tendons avoid more intensive beam-column joints reinforced area, convenient construction of prestressed reinforcement. In a six degrees of this structure system is adopted in large-scale logistics library project, built using nearly three years, the use effect is very good. But due to the system to the new structure, in the actual engineering application is less, the under vertical load and horizontal load of the elastic-plastic stress performance study is less, further popularization and application needs to be done in-depth research and analysis. For these reasons, this paper carried out the following related research work:1) Analysis of overall flexibility in loads:elastic analysis element in ANSYS is adopted for structure under vertical load and horizontal load stress analysis, analysis of the structure equivalent load and deflection displacement area biggest, at the same time to conventional prestressed curb beam structure were analyzed in comparison. Find the new large column grid prestressed concrete curb beam structure of the equivalent stress and deflection displacement is smaller than conventional curb beam structure;2) The plastic analysis under horizontal load:under the guidance of the elastic analysis results, establishing integral finite element model by SOLID65element. To prestressing tendons equivalent into the load applied to the beam corresponding position. Respectively for single layer-single span、single layer-two span and single span-two-story structure apply horizontal displacement control load. Study on structure characteristics of structures subjected to down load, the developing regularity of crack and the ability to resist horizontal load. Found the new large column grid prestressed concrete curb beam structure and conventional prestressed curb beam structure column bottom tensile zone of concrete cracking earlier. Energy absorption of new large column grid prestressed concrete curb beam structure was found by the vertex displacements and the total base shear curve is greater than conventional prestressed curb beam structure;3) The plastic analysis under vertical load:establishment of2x2cross-entity model, analysis of the destruction of the structure under the effect of vertical fracture load. Find new large column grid prestressed concrete curb beam structure and conventional prestressed curb beam structure belong to the space structure system, but new large column grid prestressed concrete curb beam structure under vertical force better mechanical performance of conventional prestressed curb beam structure;4) Design and application of theoretical analysis:according to the structure under different load of elastoplastic analysis results, after consulting a large number of relevant information, to the structure of plate, beam and column, column caps node puts forward problems that should be paid attention to in actual design.