JPS5841285Y2 - stud bolt dowel - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a dowel for stud bolts used for synthetic beams in architectural structures and for other purposes.

In order to integrate concrete and steel frames, and especially to prevent displacement in the direction of the steel frames, stud bolts 2 as shown in FIGS. 1 and 2 are used.

Conventionally, stud bolts 2 having a circular cross section as shown in the figure have been used because of their high productivity and lack of directionality during on-site construction.

However, the bolt diameter of this circular stud bolt 2 is
Due to restrictions on the welding method, etc., when using a DC welder at a construction site, the limit is usually 22 mm.

This is because if the cord (called a cabtire) between the welding machine (transformer) and the welding position at the construction site is made too thick, the construction efficiency will be greatly reduced. This is because if a diameter of 22 mm or more is to be melt-planted on the stud plate, the quality of the studs 1 to 1 will deteriorate due to poor weld penetration.

On the other hand, there is a method using an AC welder that allows the cabtire to be thinner and does not cause poor weld penetration.

However, this method using an AC welder requires a long welding time, and also requires special flux and metal fittings to prevent flux diffusion for gas sealing to prevent oxidation of the welded area during welding.

Therefore, in this method, upward and sideways welding has not yet been developed.

It is also possible to improve the integration of concrete and steel by increasing the number of stud bolts, but this has the disadvantage that the increased number of stud bolts lengthens the construction time.

This invention was devised in view of the above-mentioned circumstances, and is intended to provide a stud bolt dowel having the same cross-sectional area, the same height, and the same material as the conventional circular stud bolt, and having a superior dowel effect.

This invention will be explained below based on the drawings.

FIG. 3 shows a stud bolt dowel according to this invention, in which the stud bolt 6 has a shaft portion 6 with a square or rectangular cross section, and is welded onto a steel frame 1 such as a steel beam of H-section steel.

Further, the head 7 may be square instead of circular.

Figure 5 shows the deformation caused by the displacement of the steel frame 1 and the concrete 8 in the direction of the steel frame in the dowel of the conventional circular stud bolt 2. The bearing pressure crushing phenomenon of the concrete 8 occurs at the base, and the amount of deformation increases. growing.

At this time, the circular stud bolt 2 may easily break due to being subjected to alternating positive and negative loads that cause a kinking phenomenon.

FIG. 6 similarly shows the deformation of the rectangular stud bolt 6. Compared to the circular stud bolt 2, the bending rigidity is greater, so there is less deformation, and it is more resistant to the compressive stress received from the concrete 8. Since the stress distribution on the bearing surface becomes uniform even when the bearing pressure is applied, crushing of the concrete 8 is less likely to occur.

This is schematically expressed and compared in FIGS. 7 and 8, and an example of comparative calculation in the case of the same cross-sectional area, the same length, and the same plate quality is shown below.

This invention consists of the above-mentioned structure, and as mentioned above, it is possible to improve bending strength, bearing pressure strength, etc. with the same material and the same cross-sectional area, and without deteriorating weldability, workability, etc. A stud bolt dowel with excellent performance.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of a composite beam when using a conventional stud bolt dowel, Figure 2 is a sectional view taken along line A-A, and Figure 3 is a composite beam when using the stud bolt dowel of this invention. Fig. 4 is a longitudinal sectional view, Fig. 4 is a BB sectional view thereof, Fig. 5 is a longitudinal sectional view showing how the conventional stud bolt dowel is deformed, and Fig. 6 is a longitudinal sectional view showing how the stud bolt dowel of this invention is deformed. A longitudinal sectional view, FIG. 7 is a schematic diagram of a concrete crushing test using a conventional stud bolt dowel, and FIG. 8 is a schematic diagram of the stud bolt dowel of this invention. 1... Steel frame, 2... Circular stud bolt, 3... Shaft, 4... Head, 5...
...Rectangular stud bolt, 6 ...Shaft, 7
...Head, 8...Concrete.

Claims (1)

[Scope of utility model registration request] A stud bolt dowel characterized by having a shaft portion with a rectangular cross section.