JPH10237946A - Column base hardware and column base structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fill a grout surely by forming a bolt hole for a column base in a manner of expanding outward or in the circumferential direction of the column base and shrinking vertically or toward the underside. SOLUTION: In the column base hardware 1, the shape of a bolt hole 3, as seen from the top, expands outward and the wall surface of the hole is vertical. The shape of the bolt hole 3 may be expanded in the circumferential direction or may be tapered from the top end to the bottom end. A sheathing board 9 that is installed on the top face of a foundation concrete B, is provided around the column base hardware 1, a grout 7 is forced into the clearance between the top face of the foundation concrete B and the column base hardware 1 and the clearance between the bolt hole 3 of the column base hardware 1 and an anchor bolt 2 from one hole 4b of a washer 4 that is intended for flowing a grout, through the expanded section of the bolt hole 3 as a passage. Thus the grout can be filled smoothly and in a short time. Therefore, even column base hardware whose plane size is large can be fixed integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a column base metal and a column base structure used for a column base of a steel frame or a steel reinforced concrete building.

[0002]

2. Description of the Related Art Conventionally, as a method of fixing a steel column to foundation concrete, a column base metal is fixed to a lower end of the column, and this column base metal is inserted into an anchor bolt in which the lower end is embedded in the base concrete in advance. In many cases, a method of fixing with a nut is adopted. In the case of this method, before fixing with a nut, once a gap is provided between the foundation concrete and the column base metal and further between the anchor bolt and the column base metal, so that after the nut is tightened, the mortar is securely inserted into the gap. Or, if grout or the like is not packed, when a bending moment or a shearing force acts on the column base, a rotational deformation or a horizontal movement more than expected may occur, and the stability of the whole building may be impaired.
In order to prevent this, for example, as described in Japanese Patent Publication No. 5-63585, a grout material is simultaneously filled into the gap generated in the column base using a special washer, and the column base is integrally integrated. A fixing method has been devised.

[0003]

Problems to be Solved by the Invention
FIG. 11 shows a special washer 10 of a column base shown in Japanese Patent Publication No. 85, a state in use, FIG. 12 is a perspective view from the top side, and FIG.
As shown in the perspective view from the back side, a recess 11 for grout circulation is provided on the back side, and a through-hole 12 for grout injection or air vent is provided on the back side. In filling the grout material 7, the through holes 12 of the washer 10
The grout material 7 is press-fitted from above, and the injection state is confirmed by leaking the grout material from the through holes of the other washers.

In such a conventional column base structure, a washer 10
The grout material 7 flowing from the through hole 12 once hits the upper surface of the column base metal 1, flows laterally, and enters the lower surface side of the column base metal 1 through a gap between the bolt hole 3 and the anchor bolt 2. The grout material has the property that the fluidity decreases over time. In the conventional filling method, even if the inflow speed from the through-hole 12 is increased, the inflow speed is reduced at the time of laterally moving or wrapping around the gap of the bolt hole through the upper surface of the column base metal fitting, and the column base having a large planar dimension is reduced. In the case of metal, it takes time to fill the gaps on the lower surface of the column base metal, and there is a possibility that filling from one place and leakage from other through holes may be difficult to confirm due to a decrease in the flowability of the grout material. Further, in order to avoid this, there is a problem that the pressure for filling the grout material must be increased and the dam plate 9 must be strengthened.

[0005] When a force for pulling up the column A or bending stress is applied due to an earthquake or the like, a nut 5 attached to an upper portion of the anchor bolt 2 receives a lifting force by a washer via a washer. Resist by holding down. In this case, the washer receives a compressive force from the contact surface of the nut 5 on the upper surface. When the acting load is low, the grout material 7 packed into the washer recess also resists against the upper surface of the column base metal 1 and suppresses the floating of the column base metal.
After the compression fracture occurs, the resistance becomes a gate-shaped metal shape having the recess 11 as a void. At this time, the special washer 1 is formed because the recess 11 has a shape that covers the bolt hole 3 in a wide range.
Since a large bending moment is applied to the plate portion on the top surface of the special washer 10, the plate on the top surface of the special washer 10 must be made thick.

Further, in addition to the thickness of the plate portion above the washer, a thickness for providing the concave portion 11 is required, and the total thickness of the special washer 10 is increased. (2) The height to the upper end increases, the amount of concrete on the floor increases, and workability deteriorates. Also, Japanese Patent Application Laid-Open
Japanese Patent Application Laid-Open No. -102639 discloses a column base hardware connected to a bolt hole and provided with a mortar injection hole and a mortar filling detection hole opened on the upper surface. It is a small hole similar to the hole, and it is difficult to reliably fill the inside with a mortar having a property that the fluidity rapidly decreases with time from the filling hole.

[0007]

SUMMARY OF THE INVENTION A column base metal fitting of the present invention has been made to solve the above-mentioned problem, and an anchor bolt is inserted from below into a plurality of bolt holes and fixed from above with a washer and a nut. A column base metal used for a column base structure, wherein the shape of the bolt hole is enlarged in an outer direction or a circumferential direction of the column base metal when viewed from an upper surface side, and the shape of the bolt hole is enlarged when viewed from a cross section. The wall surface of the portion is formed of a vertical surface from the upper end to the lower end and / or an inclined surface having a smaller hole diameter from the upper end to the lower end.

A second invention of the present invention relates to a column base structure in which a column base metal fixed to a lower portion of a column material is fixed by anchor bolts buried in a lower portion of the foundation concrete. The shape of the bolt hole of the metal is enlarged in the outward or circumferential direction of the column base metal when viewed from the upper surface side, and the wall surface of the bolt hole is perpendicular to the lower surface edge from the upper surface end when viewed from the cross section. And / or an inclined surface having a smaller hole diameter from the upper surface end to the lower surface end, the upper portion of the anchor bolt is inserted through the bolt hole of the column base metal fitting and the bolt hole of the washer, and the nut is screwed together with the base. A column characterized in that the gap between the upper surface of the concrete and the lower surface of the column base metal fitting and the gap between the bolt hole of the column base metal fitting and the anchor bolt are filled with grout material and the foundation concrete and the column base metal fitting are integrally fixed. leg It is an elephant.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the column base metal according to the present invention, the peripheral wall of the bolt hole can be provided perpendicular to the column base metal, and the wall surface of the bolt hole extends from the upper end to the lower end when viewed from the cross section. An inclined surface with a gradually decreasing hole diameter, that is, a taper can also be provided. If the bolt hole peripheral wall is provided with a taper in the direction in which the grout material flows into the column base metal center side in this way, the grout material flows more smoothly into the bolt hole periphery and the column base metal center,
The workability of filling the grout material can be further improved.

Of course, without departing from the spirit of the present invention which exerts the specific effects of the present invention, an inclined surface is provided below the vertical wall surface of the bolt hole, or a tapered surface (inclined surface) of the bolt hole. May be provided. Furthermore,
At the periphery of the upper surface of the bolt hole whose plane shape is enlarged in the outer peripheral direction or the peripheral direction of the pillar base metal, a stamp or a mark indicating the center position of the anchor bolt inserted into the hole, or the anchor bolt is attached to the periphery of the bolt hole. A notch, a slit, a protrusion, or the like serving as a guide indicating the center position may be provided.

The bolt holes need to be larger than the diameter of the anchor bolt in all portions so that the grout material can be injected into the lower part of the column base metal by the bolt hole portions. For example, the normal position of the anchor bolt can be determined to be the center position of the circle, and the anchor bolt can be inserted in increments.When the anchor bolt is inserted, if the enlarged shape of the bolt hole is, for example, elliptical, Is likely to be unknown.
However, if there is a mark or the like indicating the normal center position of the anchor bolt as described above, it becomes a guide when the anchor bolt is inserted, and a more favorable effect can be provided in the construction.

Incidentally, the bolt holes of the column base metal can be formed by cutting, fusing and pressing, and can also be integrally manufactured by casting or forging. Also, a mark or the like serving as a position guide for the anchor bolt around the bolt hole can be formed in the same manner. Further, a projection protruding from the lower surface of the washer, for example, a downward projection formed by pressing a grout circulation hole or a projection separately provided around the grout circulation hole, to prevent rotation of the washer beyond an allowable range. With the restraining mechanism, it is possible to prevent a danger that the washer is rotated by the rotation of the nut that is grounded on the upper surface of the washer, and the grout flow hole of the washer is disengaged from the bolt hole, thereby obstructing the flow of the grout material.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. 1 to 7 show a first embodiment. 1 and 2 are an overall schematic side view and a schematic plan view of a first embodiment of a column base structure of the present invention. FIG. 3 is a cross-sectional view of a main part, and FIGS. 6 and 7 are perspective views of column base hardware. In these figures, the column base hardware has the same structure. As shown in a plan view in FIG. 4 and a cross-sectional view in FIG. 5, a column base metal fitting 1 shown in this embodiment is fixed to a lower end of a column A, and a bolt inserted through an upper portion of an anchor bolt 2. The bolt hole 3 has a planar shape that is planarly enlarged outward of the column base 1, and the wall surface of the hole is a vertical surface.

The column base metal 1 may have a structure that can be manufactured from a flat plate steel plate as shown in FIG. 6 or may have a form that can be manufactured by casting or forging as shown in FIG. In order to form the bolt hole 3 in which the hole is enlarged in the outer direction or the circumferential direction of the column base metal 1 in this manner, cutting, fusing, and pressing are performed. In the case of casting and forging, a mold is prepared in advance. It can also be manufactured. When the column base metal 1 fixed to the lower end of the column A is installed on the foundation concrete B, a level adjusting material 8 is placed as a spacer at a required position on the upper surface of the foundation concrete B, and the column base metal is placed thereon. 1 and the upper part of the anchor bolt 2 whose lower part is buried in the concrete of the base concrete B is inserted into the bolt hole 3 and the bolt hole 4a of the washer 4 which are excessively larger than the bolt diameter of the column base hardware 1, The nut 5 is screwed and tightened.

The washer 4 has a flat plate shape. In this embodiment,
As shown in FIGS. 2 and 3, etc., holes 4b for grout circulation or air vent opening to the planar enlarged portion of the bolt hole.
Are formed and installed so as to cover the bolt hole 3 in a planar manner. When filling the grout material 7, FIG.
As shown in FIG.
A weir plate 9 is provided on the upper surface, and the grout material 7 is pressed into the grout distribution hole 4b of the washer 4 at one place, and the bolt hole 3 is formed.
The gap between the upper surface of the foundation concrete B and the lower surface of the column base 1 and the bolt hole 3 of the column base 1
The grout material 7 is filled in the gap between the bolt and the anchor bolt 2 to integrally fix the column base.

Since the present embodiment is formed as described above, the grout material can be filled smoothly and in a short time, and a column base metal having a large plane dimension can be used as shown in FIGS. The grout material 7 can be reliably filled in the gap generated when the metal piece 1 is placed on the foundation concrete B, and the column base can be integrally fixed. On the other hand, the washer 4 can be a washer having a simple shape of a flat plate, and the contact area with the upper surface of the column base metal 1 can be made larger than before, so that the stress load on the washer 4 can be reduced, so that the plate thickness is small. It can be. Furthermore, since the washer 4 has a small thickness, the height from the upper surface of the column base hardware 1 to the upper end of the anchor bolt 2 can be reduced, so that it is easy to prevent the anchor bolt from projecting from the finished surface of the floor.

In this embodiment, the column A is a square steel tube. However, a similar column base metal and column base structure can be used for a circular steel tube, an H-shaped steel, or a cross-shaped column combining steel materials. Further, in this embodiment, the case where the number of anchor bolts is four is shown. However, even when the number of anchor bolts exceeds four, the same column base hardware and column base structure can be used. FIGS. 8A and 8B show examples of the planer shape of the column base hardware in the case of eight anchor bolts. (A) of FIG.
(B) In both cases, the planar shape of the bolt hole 3 is enlarged in a plan view in the outer circumferential direction or the circumferential direction of the column base hardware 1.

Next, FIG. 9 shows a column base hardware and a column base structure according to a second embodiment of the present invention. FIG. 9 is a cross-sectional view of a main part at the same position as FIG. 3 of the first embodiment. FIGS. 2, 4, 6 and 7 of the explanatory view of the first embodiment are almost the same in the case of the second embodiment. The difference between the present embodiment and the first embodiment is that, as shown in FIG. 9, the periphery of the pillar base metal fitting 1 on the side of the bolt hole 3 on the enlarged side tapers from the upper surface of the base metal fitting to the lower surface. (That is, an inclined surface) 6 is provided. The method of forming the tapered surface 6 on the peripheral edge of the bolt hole 3 can be the same as described above, such as cutting, fusing, and pressing, and in the case of casting and forging, a mold can be prepared in advance and manufactured.

The procedure for tightening the column base hardware 1 to the foundation concrete B can be the same as in the first embodiment. When filling the grout material 7, the grout material 7 injected from the grout flow hole 4b of the washer 4 flows through the tapered surface 6 toward the lower periphery of the bolt hole 3 and the center of the column base hardware. This has the effect of further improving the filling of the lower surface of the pillar base 1 as compared with the case where the grout material 7 is injected vertically. Next, FIG. 10 shows another embodiment of the planar shape of the bolt hole 3. FIG. 10 is a plan view showing a main part of a bolt hole 3 according to the present invention, showing an upper plan shape thereof and also showing a relationship with an anchor bolt 2 inserted into the hole.

While the conventional bolt hole has a generally circular bolt hole shape that is substantially the same as the cross-sectional shape of the anchor bolt, FIG. It is an enlargement. In this way, when not only the egg shape but also a part of the outer periphery of the bolt hole 3, preferably approximately a half of the outer periphery is gently expanded in a planar manner, the area of the grout circulation hole 4 b of the washer 4 is smaller than Also, there is an advantage that the area of the enlarged portion can be relatively large, and even if the position of the grout flow hole 4b is displaced by the horizontal movement of the washer 4, the filling property of the grout material 7 can be ensured well. On the other hand, (b) shows a bolt hole 3 in a part of the periphery of a perfect circular bolt hole.
(C) is a projection in which the number of holes is increased while providing the same projection as in (b), and the number of the enlarged holes is selected as the grout material 7 flow path. You can increase the number of branches. It should be noted that there is no problem in combining the shapes of the bolt holes 3 or changing the outer shape curve to a straight line.

In any of the embodiments shown in FIGS. 10A and 10B, an enlarged hole serving as a flow passage for the grout 7 is provided in the bolt hole 3 itself in a limited direction. In this case, the contact area between the back surface of the washer 4 and the upper surface of the column base 1 can be made larger than in the conventional case, and the washer 4 can be made smaller. The direction of the hole enlargement may be either direction in consideration of workability, for example, when the column shape is a cross shape and the distance between the bolt hole 3 and the column is large, but a square steel pipe or a circular steel pipe may be used as the column. When the distance between the anchor bolt 2 and the column A is short in this case, it is preferable to set the outer direction or the circumferential direction of the column base metal 1 rather than the column A side in consideration of the filling workability of the grout material 7.
In addition, since the enlargement of the bolt hole 3 tends to lead to a cross-sectional defect of the column base 1, when securing the strength and rigidity of the column base, the column side where the bending moment becomes large is usually avoided, and the column base metal is used. It is preferable to enlarge the hole toward the outer peripheral side of 1.

FIG. 10A shows an example of a mark 3a indicating the normal center position of the anchor bolt 2. (A)
In the case where the hole is enlarged in one direction as described above, it is sufficient to provide at least three marks where the extension lines are orthogonal. still,
The mark can be similarly formed in (b) and (c), but the center position of the anchor bolt 2 can also be indicated by making the extension lines of the projections orthogonal as shown in (c).

In the flat washer 4 used to form the column base structure of the present invention, the grout circulation hole 4b of the washer 4 installed on the upper surface of the bolt hole 3 is as shown in FIG. In order to inject the grout material 7 and bleed the air, and to check the filling state due to leakage of the grout material 7, the grout material 7 must be opened to the bolt hole side. When the nut 5 placed on the upper surface of the washer 4 is rotated to fasten the column base 1 to concrete, there is a possibility that the washer 4 rotates together with the nut 5 and the grout circulation hole 4b may come off from the bolt hole 3. If there is, a protrusion protruding toward the bolt hole 3 on the lower surface of the washer 4, for example, a downward protrusion formed by pressing a grout flow hole 4 b or a separately provided protrusion for the grout flow hole of the washer 4. 4b may not be detached from the bolt hole 3 in a planar manner. However, when the enlarged portion of the bolt hole 3 exists outside the washer, the enlarged portion outside the washer serves as an opening even if the washer is not provided with a grout circulation hole.

[0024]

According to the column base metal fitting of the present invention, the shape of the bolt hole is enlarged in the outward or circumferential direction of the column base metal when viewed from the top side, and the wall surface of the bolt hole is viewed when viewed from the cross section. Because it consists of a surface that is perpendicular from the upper surface end to the lower surface end and / or an inclined surface whose hole diameter decreases from the upper surface end to the lower surface end,
The gap generated when the column base metal is installed on the foundation concrete can be reliably filled with grout material to fix the column base integrally, and the bolt hole itself of the column base metal can be placed outward or around the circumference of the column base metal. The portion expanded in the direction becomes a grout flow passage through which grout can flow directly from the upper surface of the column base metal to the lower surface, and the grout material flows directly into the gap on the lower surface of the column base metal without temporarily staying on the upper surface of the column base metal. The grout material can be filled smoothly and in a short time even with a column base metal having a relatively large plane dimension, and the inflow pressure can be reduced.

When the column base metal of the present invention is used, the washer can have a simple flat cross-sectional shape, and the contact area of the washer with the top surface of the column base metal can be made larger than before. Since the stress burden on the washer can be reduced, the washer can be made thinner. Furthermore, since the washer is thin, the height from the upper surface of the column base metal fitting to the upper end of the anchor bolt can be reduced, so that the protrusion of the anchor bolt from the finished surface of the floor can be reduced. Furthermore, since the shape of the washer is simple, manufacturing, transportation, and inventory management are easy, and costs can be reduced as a whole. In addition, at the periphery of the upper surface of the bolt hole in which the planar shape of the hole is enlarged in the outer circumferential direction or the circumferential direction of the pillar base metal, a mark or mark indicating the center position of an anchor bolt inserted into the hole, or an anchor at the periphery of the bolt hole. By providing a notch, a slit, a projection, or the like that serves as a guide indicating the center position of the bolt, it can be used as a guide when inserting the anchor bolt.

Further, a projection protruding toward the bolt hole side on the lower surface of the washer, for example, a downward projection formed by pressing a grout circulation hole, and a projection separately around the grout circulation hole are provided. If you have a rotation restraint mechanism more than necessary,
It is possible to prevent a danger that the washer is rotated by the rotation of the nut that is grounded on the upper surface of the washer, and the grout distribution hole of the washer is disengaged from the bolt hole to hinder the flow of the grout material.
Next, the column base structure of the present invention can reliably fill the gap formed when the column base metal is installed in the foundation concrete with the grout material and integrally fix the column base portion. Since the grout material can be filled smoothly and in a short time, the column base can be integrally fixed even with a column base metal having a large planar dimension.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an example of a column base hardware and a column base structure of the present invention.

FIG. 2 is a schematic plan view of FIG.

FIG. 3 is a sectional view of a main part of FIG.

FIG. 4 is a plan view of an example of a column base hardware of the present invention.

FIG. 5 is a sectional view of the column base hardware taken along line A-A 'of FIG. 4;

FIG. 6 is a perspective view of the column base hardware of FIG. 4;

FIG. 7 is a perspective view of a column base hardware of the present invention.

FIG. 8 is a plan view of another embodiment of the column base hardware of the present invention.

FIG. 9 is a cross-sectional view of a main part of another embodiment of the column base hardware of the present invention.

FIG. 10 is a plan view of a main part showing another embodiment of the bolt hole of the column base metal according to the present invention.

FIG. 11 is a sectional view of a main part showing a conventional column base structure.

FIG. 12 is a top perspective view of a conventional special washer.

FIG. 13 is a perspective view of the lower surface side of a conventional special washer.

[Explanation of symbols]

 A pillar B foundation concrete 1 pillar base 2 anchor bolt 3 bolt hole 3a mark 4 washer 4a bolt hole 4b hole 5 nut 6 tapered surface 7 grout material 8 level adjusting material 9 dam plate 10 special washer 11 recess 12

Claims (2)

[Claims] An anchor bolt is inserted into a plurality of bolt holes from below, and is used in a column-base structure in which an anchor bolt is fixed from above with a washer and a nut, wherein the shape of the bolt hole is viewed from an upper surface side. In addition to being enlarged in the outward direction or the circumferential direction of the column base hardware, the wall surface of the enlarged portion of the bolt hole is viewed from the cross section so that the wall surface of the enlarged portion is perpendicular from the upper surface end to the lower surface end and / or from the upper surface end. A column-base metal fitting comprising an inclined surface having a smaller hole diameter toward a lower surface end. 2. In a column base structure in which a column base metal fixed to a lower portion of a column material is fixed by anchor bolts buried in a lower part of a foundation concrete, a shape of a bolt hole of the column base metal is an upper surface side. When viewed from the top, it is enlarged in the outward or circumferential direction of the column base hardware, and when viewed from the cross section, the wall surface of the bolt hole is oriented perpendicularly from the upper end to the lower end and / or from the upper end to the lower end. The upper part of the anchor bolt is inserted into the bolt hole of the column base metal and the bolt hole of the washer, the nut is screwed, and the upper surface of the foundation concrete and the lower surface of the column base metal member are formed. A column base structure characterized in that the gap and the gap between the bolt hole of the column base metal and the anchor bolt are filled with a grout material to fix the foundation concrete and the column base metal integrally.