Study On Calculation Methord For Folding Steel Beam And Concrete Column Hybrid Structure Based On Semi-rigid Connections

Due to the double advantages of the better economy and high reliability,folding steel beam and concrete column hybrid structure are usually the best solutions in the form of some large factory building structure form. Due to various reasons, study for the folding steel beam and concrete column hybrid structure connection node is less now, and has not formed a mature theory. During the actual design and construction process, this kind of structure is dealed as hinged frames or portal frames, which are a little different from semi-rigid node force conditions. All above statements hindered the promotion of such structure. So the study for semi-rigid node actual force conditions of the structure that is especialy subjected to bending moment, which makes the design and calculation of structures be closed to the actual loading better, avoiding unnecessary wastes and having the important value of engineering research.Take helical spring to simulate the semi-rigid nodes Semi-rigid in this paper, and the static analysis of semi-rigid connection of folding steel beam and concrete column hybrid structure are according to level two hinge line arch spring support. In vertical uniformly distributed load was deduced calculation formula which is under the action of the structure node bending moment, displacement and shear force, and the initial rotational stiffness calculation formula of anchor connection nodes for anchor bolt and end plate under the action of bending moment was deduced too. Verified the feasibility of the formula in combining with concrete examples. With ANSYS finite element software the practical engineering anchor bolt endplate connection nodes are simulated, and analysis and combine the displacement and force of just answer structure node and hinged structure nodes, which further verifing the feasibility of the formula. Finally, based on the node model, change the initial rotational stiffness influence factors, and discusse the node initial rotational stiffness varies with the changing rule of the influence factors.Studies have shown that semi-rigid connection nodes are a kind of nodes between just answer nodes and articulated nodes, which can assume part of the bending moments., With the increase of initial rotational stiffness the moments shared by increased gradually, and the moments shared by the column foots and folding steel beam midpoint was gradually reduced. Semi-rigid node under the action of bending moment, the stresses of the most outside anchor bolt, the part outside anchor bolt bar in contact with the plate position the most outside are largest, stresses for fold at the bottom of the beam and plate edge is larger. Anchor bolts showed elongation deformation, the parts of plate edge small showed buckling deformation and nut screw bending deformation occurred. With the anchor bolt diameter, thickness of end plate, the number of anchor bolt and the column section area increasd, the initial rotational stiffness increased gradually, but when it increased to a certain degree, the influence of the change of the influence factors for rotation stiffness is no longer significant...