JPH0441737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for joining steel pipe concrete columns.

[Conventional technology]

Generally, steel pipe concrete columns for structures are constructed by forming a column member in advance by pouring concrete into a steel pipe at a factory, transporting the column member to a construction site, and connecting a plurality of the column members at the construction site.
Figures 8 and 9 show the conventional method of joining steel pipe concrete columns, where a is a cross-sectional view and b is a cross-sectional view.
is a front view. In the figure, 1 is a steel pipe, 2 is a batten, 3 is a high-tensile bolt, 4 is concrete cast on site, and 5
is factory-cast concrete.

The above-mentioned column members are formed in advance in a factory, and the upper and lower joints are not filled with concrete 5 at the factory, and after being transported to the construction site, the joints of the steel pipes of the column members are joined at the site. , the joint portion is filled with concrete 4 to form a steel pipe concrete column. As shown in Figure 8, the method for joining steel pipes at construction sites is as follows:
There is a method using battens 2 and high-tensile bolts 3, and a method using on-site butt welding using a backing metal 7, as shown in FIG.

[Problem that the invention seeks to solve]

However, the conventional bonding method described above has the following problems.

(1) The concrete becomes discontinuous at the joints of the column members, and there is almost no adhesive force between the steel pipe 1 and the concrete 4, so stress cannot be transmitted through the concrete at the joints.

(2) In order to obtain sufficient joint strength, the number of high-tensile bolts will increase.

(3) When pouring concrete into joints on site,
The air at the joint cannot be removed completely, causing air pockets.
There is a possibility that the compressive force cannot be sufficiently borne.

(4) In order to obtain sufficient joint strength, it is necessary to perform butt welding in which the steel pipes of the upper and lower columns are completely fused at the joint, but it takes time and effort to process the backing metal 7 at the corner of the square steel pipe. At the same time, if the processing accuracy is poor, welding defects are likely to occur. Furthermore, welding becomes difficult if the steel pipes have different thicknesses.

The present invention was made in order to solve the above-mentioned problems in the conventional method of joining steel pipes and concrete columns, and it is an object of the present invention to provide a joining method with high reliability of strength.

[Means for solving problems]

In order to achieve the above object, the method for joining steel pipe concrete columns according to the present invention is performed by the following steps.

(1) The lower surface of the factory-cast concrete of the upper column among the column members is an inclined surface, and an air vent hole is drilled in the steel pipe at the upper end of the inclined surface, and a concrete injection hole is provided in the steel pipe of the lower column member. .

(2) A plurality of opposing battens are fixed to the upper and lower outer peripheries of the column member, one of which slightly protrudes from the end of the steel pipe, and the other of which is retracted from the end of the steel pipe.

(3) Install one or more reinforcing bars at either the upper or lower joints of the column members.

(4) Transport the column members formed as above to the construction site.

(5) At the construction site, the above-mentioned column members are brought into contact with the ends of the steel pipes at the joint, and the opposing battens are welded together.

(6) Concrete is then poured into the joint from the concrete injection port, and the concrete injection port is then closed to complete the joint.

[Effect]

The joining of the steel pipe concrete column according to the present invention is performed as described above. First, the bottom surface of the factory-cast concrete is sloped and air vent holes are drilled, which prevents the formation of air pockets inside the concrete at the joint. The reliability of the strength of the joint is greatly improved due to the welding of the steel and the placement of reinforcing bars at the joint. Since one of the battens is made to protrude from the end of the steel pipe and the other is retracted from the end of the steel pipe and fixed, the batten serves as a guide when joining the column members, which is convenient for the joining work.

[Embodiments of the invention]

Fig. 1 shows a method of joining a steel pipe concrete column according to an embodiment of the present invention.a is a side sectional view, b is a plan sectional view, and c is a front view.In the figure, 11 is a steel pipe, 12
13 is the factory-cast concrete,
14 is the lower surface of concrete poured in a factory, 15 is a batten, 16 is a concrete injection port, 17 is an air vent, 18 is a reinforcing bar, 19 is concrete, and 20 is a reinforcing plate.

In joining a steel pipe concrete column according to the present invention, a column member previously formed in a factory is transported to a construction site, and a plurality of column members are joined at the site to form a steel pipe concrete column. The lower surface 14 of the factory-cast concrete 13 of the column member is an inclined surface, one or more air vent holes 17 are bored in the steel pipe at the upper end of the inclined surface 14, and a concrete injection hole 16 is provided in the lower column member. will be established. In addition, flat steel battens 15 are fixed to the outer periphery of the upper and lower ends of the note member so as to face each other. As shown in FIGS. 3 and 4, among the opposing battens 15 fixed to the outer periphery of the upper and lower ends of the column member, one of the battens 15 has its end slightly closer to the end of the steel pipe. It protrudes and is fixed, and the other batten 15 is retracted from the end of the steel pipe by the amount of the protrusion and is fixed. Further, one or more reinforcing bars 18 are arranged in the longitudinal direction of the column at either the upper or lower joint portion of the column member.

The column members configured in this manner are transported to a construction site and joined at the construction site to form columns of a structure. That is, to join the column members, the upper end of one of the two column members and the lower end of the other are brought into contact, the battens 15 fixed to the outer periphery of each are butted, and the abutting portions are welded. As mentioned above, the batten 15 is fixed slightly in and out of the end of the steel pipe, so when joining two column members, the batten 15
has a guide function and is convenient for joining. After joining the column members, concrete 19 is injected into the joint portion through the concrete injection port 16, and then a reinforcing plate 20 is welded to the injection port 16 to close the injection port 16, thereby completing the joining of the column members.

In the above-mentioned column member, the lower surface 14 of the factory-cast concrete is sloped, and the air vent hole 17 is bored in the steel pipe at the upper end of the slope, so that air is completely removed when pouring the concrete 19, and the concrete 19 is completely degassed. This prevents the formation of air pockets in the joint 19, and together with the welding of the battens 15 and the provision of reinforcing bars 18 at the joint, the reliability of the strength of the joint is significantly improved.

In addition, when the protrusion 12 is provided on the inner surface of the steel pipe 11, the adhesive force between the steel pipe 11 and the concrete 13, 19 increases, and mechanical stress transmission becomes possible between the steel pipe and the concrete. Note that instead of the protrusion 12, a stud, a dowel, or the like may be fixed to the inner surface of the steel pipe 11.

Furthermore, in batten welding when joining column members, since the steel pipe 11 functions as a back metal, highly reliable welding is possible. Note that the steel pipe 1 of the batten 15
Factory welding to 1 may be fillet welding if the necessary throat thickness and welding length are available.

Figures 2 to 4 show other embodiments; Figure 2 is a cross-sectional view, Figures 3a and b are for square steel pipes, and Figures 4a and b are for circular pipes. FIG.
When pouring concrete 13 onto steel pipes 11 at a factory, reinforcing bars 18 are placed together with concrete 13 at either the upper or lower joint of the column member, thereby saving the effort of placing reinforcing bars 18 at the construction site. You can stay there. This is effective in reducing the construction period and costs of on-site factories.

5 to 7 show other embodiments using reinforcing bars 18 of different shapes; a is a plan view, and b is a side sectional view. Figure 5 shows a round steel with a head, Figure 6 shows a shaped steel with a projection, and Figure 7 shows a steel pipe with an external projection.
This is an example used in place of .

〔Effect of the invention〕

Since the steel pipe concrete column of the present invention is constructed as described above, it has achieved the following excellent effects.

(1) The lower surface of the factory-cast concrete for the column members is sloped, and air vent holes are provided in the steel pipe at the top of the slope, so that the factory-cast concrete and the concrete at the joint are integrated, and the joint Complete deaeration during filling of concrete into the joint prevents the formation of air pockets, greatly improving the reliability of the strength of the joint.

(2) By joining steel pipes using battens and installing reinforcing bars at joints, we reduced the use of high-tensile bolts to join column members, reducing costs.

(3) Furthermore, by providing protrusions on the inner surface of the steel pipe, the joint strength between the steel pipe and the filling concrete at the joint is increased, and the filling material and the filling material can withstand the bending moment that occurs inside the column due to lateral dynamic loads such as earthquakes. This can be countered with partial reinforcement materials.

[Brief explanation of the drawing]

Fig. 1 shows a method for joining steel pipe concrete according to an embodiment of the present invention.a is a side sectional view, b is a plan sectional view, c is a front view, and Fig. 2 is a joint of steel pipe concrete columns according to another embodiment. Fig. 3 is a perspective view of the joint of column members made of square steel pipes, a is a perspective view of the upper column member, b is a perspective view of the lower column member, and Fig. 4 is a perspective view of the joint of column members made of circular steel pipes, a is the upper column. Of the members, b is a perspective view of the lower column member, FIGS. 5 to 7 are plan sectional views, b are side sectional views, and FIG.
9 are side sectional views of the joints of conventional steel pipe concrete columns. In the figure, 11 is a steel pipe, 12 is an inner protrusion, 13 is factory-cast concrete, 14 is the bottom surface of factory-cast concrete, 15 is a batten, 16 is a concrete injection port, 17 is an air vent hole, 18 is a reinforcing bar, 19 20 is the concrete at the joint, and 20 is the reinforcing plate.

Claims (1)

[Scope of Claims] 1. After transporting a steel pipe concrete column member, which is made by filling the parts of the steel pipes with concrete except for the upper and lower joints at a factory, to a construction site, and joining the joints of the column members at the construction site. , in a method of joining a steel pipe concrete column in which concrete is poured into the joint part to form a steel pipe concrete column, the lower surface of the factory-cast concrete of the upper column among the above column members is an inclined surface, and the upper end of the inclined surface is In addition to drilling an air vent hole in the steel pipe, a concrete injection hole is provided in the lower column member, and a plurality of opposing battens are installed on the upper and lower outer peripheries of the steel pipe of the column member. One end is slightly protruded from the end of the steel pipe at the joint, and the other is fixed by retracting the end slightly from the end of the steel pipe at the joint. A plurality of reinforcing bars are arranged inside the column to form a column member, and the column member is transported to a construction site, and the lower edge and the upper edge of each column member are brought into contact at the construction site, A method for joining steel pipe concrete columns, characterized in that after welding the abutting portions of each batten, concrete is filled into the welded portion through the injection port. 2. The steel pipe concrete column according to claim 1, wherein the method for arranging the plurality of reinforcing bars is a method of arranging the reinforcing bars together with concrete in a steel pipe when concrete is placed in the column member. joining method. 3. The method for joining a steel pipe concrete column according to claim 1, wherein a protrusion is provided on the inner surface of the steel pipe constituting the column member.