Steel-concrete composite beam
Technical field
The utility model belongs to technical field of civil engineering, particularly, relates to a kind of steel-concrete composite beam.
Background technology
In steel-concrete composite beam, shear connector need be set come Transfer of Shear, stressed jointly to guarantee girder steel and concrete beam, shear connector is a kind of shear connector commonly used, and is axial arranged along beam in steel-concrete composite beam usually.Under the axial load effect, because there are axial deformation in girder steel and concrete beam self, cause axial load mainly to be born by 3~5 row's shear connectors of steel-concrete composite beam end, the load of shear connector distributes and presents big, the middle little inhomogeneous state in two ends, correspondingly, the stress distribution of girder steel and concrete beam also presents big, the middle little inhomogeneous state in two ends.Such load and stress distribution can cause the end member of steel-concrete composite beam to destroy prior to the middle part member, have reduced the safety factor of steel-concrete combined structure.
Based on this, need a kind of shear connector load that can improve in the steel-concrete composite beam badly and distribute, do not reduce the form of structure of its mechanical property again.
The utility model content
For overcoming the defective that the shear connector set-up mode exists in the existing steel-concrete composite beam, the utility model provides a kind of to be convenient to implement, simple and reliable steel-concrete composite beam.
The utility model is realized above-mentioned purpose by the following technical solutions:
Steel-concrete composite beam comprises girder steel, concrete beam, perforate steel plate and the reinforcing bar that runs through with ribbing; The perforate steel plate is welded on the surface on the girder steel edge of a wing; Have the circular hole corresponding with the perforate steel plate on the web of girder steel; The reinforcing bar that runs through with ribbing passes from the circular hole center on perforate steel plate and the steel beam web plate; Concrete beam is cast in the periphery of girder steel, wraps up described perforate steel plate, the reinforcing bar that runs through with ribbing.
Preferably, the perforate steel plate be welded on girder steel the edge of a wing above and/or under the surface.
Preferably, the Circularhole diameter of perforate steel plate is fixed value, and the minimum range at circular hole edge and perforate steel plate edge is not less than half of Circularhole diameter, and the distance at circular hole edge and circular hole edge is not less than 1.5 times Circularhole diameter.
Preferably, the described reinforcing bar that runs through with ribbing is common hot rolling or cold rolled reinforcing steel bar with ribs, and its diameter is not more than 30mm, and is not less than 16mm.
Preferably, the perforate steel plate by along beam longitudinally fillet weld be welded on the surface on the girder steel edge of a wing.
Because adopt technique scheme, steel-concrete composite beam of the present utility model has following beneficial effect:
1, the utility model has improved the load distribution of shear connector in the steel-concrete composite beam.Reduce its shear stiffness by increasing the end shear connector diameter that runs through reinforcing bar with ribbing, thereby reduce the load that the end shear connector is born; To span centre, the shear stiffness of shear connector reduces continuously from the end of steel-concrete composite beam, makes that the interior force level of all shear connectors reaches unanimity in the steel-concrete composite beam.
2, the utility model has improved the stress distribution of steel-concrete composite beam.Improved the inhomogeneous state of internal force of shear connector by the shear connector arrangement form of continuous variable-stiffness, correspondingly, the stress concentration phenomenon of the girder steel of steel-concrete composite beam end and concrete beam also can improve.
3, the utility model can improve the safety factor of steel-concrete composite beam.Increase the shear stiffness that the diameter that runs through reinforcing bar with ribbing can reduce shear connector, simultaneously, also can improve the supporting capacity of shear connector.It is bigger that end shear connector with ribbing run through bar diameter, and bearing capacity is higher, has improved the safety factor of steel-concrete composite beam.
Description of drawings
Fig. 1 is steel-concrete composite beam schematic diagram of the present utility model;
Fig. 2 is the schematic side view of the utility model Fig. 1;
Fig. 3 is the schematic top plan view of the utility model Fig. 1;
Fig. 4 is the A-A generalized section of the utility model Fig. 3;
Among the figure: 1, the reinforcing bar that runs through with ribbing, 2, the perforate steel plate, 3, girder steel, 4, concrete beam.
The specific embodiment
Below, by reference to the accompanying drawings continuous variable-stiffness shear connector formula steel-concrete composite beam of the present utility model is further described.
As shown in Figure 1, this steel-concrete composite beam structure comprises: girder steel 3, concrete beam 4, perforate steel plate 2 and the reinforcing bar 1 that runs through with ribbing; Perforate steel plate 2 by along beam longitudinally fillet weld be welded on the upper and lower surface on the girder steel 3 upper and lower edges of a wing; Have the circular hole corresponding with perforate steel plate 2 on the web of girder steel 3; The reinforcing bar 1 that runs through with ribbing passes from the circular hole center on perforate steel plate 2 and girder steel 3 webs; Concrete beam 4 is cast in the periphery of girder steel 3, wraps up described perforate steel plate, the reinforcing bar that runs through with ribbing.By the concrete tenon in the perforate steel plate circular hole and the shearing that runs through between reinforcing bar opposing girder steel and the concrete beam with ribbing.
As Fig. 2, shown in Figure 3, from the two ends of compound beam to the center, the diameter that runs through reinforcing bar 1 with ribbing reduce successively (that is: drain into the 5th row by first of two ends, the diameter that runs through reinforcing bar 1 with ribbing reduces successively, from the 5th queue to the third side to, all diameter unanimities that run through reinforcing bar 1 with ribbing), shear stiffness increases successively, and bearing capacity reduces successively, can alleviate the stress concentration phenomenon of end, can increase the bearing capacity of end shear connector again, improve the safety factor of steel-concrete composite beam.
As shown in Figure 4, perforate steel plate 2 is welded on the upper and lower surface on the edge of a wing of girder steel 3; The Circularhole diameter of perforate steel plate is fixed value, and the minimum range at circular hole edge and perforate steel plate edge is not less than half of Circularhole diameter, and the distance at circular hole edge and circular hole edge is not less than 1.5 times Circularhole diameter.
The described reinforcing bar that runs through with ribbing is common hot rolling or cold rolled reinforcing steel bar with ribs, and its diameter is not more than 30mm, and is not less than 16mm.