JPH0223648B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a structure for vertically supporting and fixing steel columns used in various buildings on a foundation.

(Prior art and its problems) Generally, a base plate is fixed to the lower end of the steel column as described above, and the periphery of this base plate is fastened to the foundation using anchor bolts. If you want to support a steel column vertically by simply placing it on top, the horizontal accuracy of the top surface of the foundation and the perpendicular accuracy of the base plate to the steel column must be perfect, but in reality it is impossible to satisfy both of these requirements. Since this is almost impossible, after adjusting the verticality of the steel column whose lower end is placed on the foundation, the lower end of the steel column is fixed to the foundation.

In other words, the conventional method of supporting and fixing steel columns is as follows:
As shown in Fig. 1, the verticality of the steel column 1 is adjusted by driving a small piece of iron plate or a wedge made of iron plate 4 of an appropriate thickness between the periphery of the base plate 2 fixed to the lower end of the steel column 1 and the foundation 3. After that, there is a method of fixing the periphery of the base plate 2 and the foundation 3 with anchor bolts 5 and nuts 6, or a method of fixing the foundation 3 to the base plate 2 as shown in FIG.
A mortar mound 7, which is generally called a "manjiyuu" at the site, is formed on top, and by placing the center bottom of the base plate 2 on this mound 7, the steel column 1 can be moved in any direction 360 degrees. There is a known method of filling the space between the base plate 2 and the foundation 3 with concrete 8 after adjusting the verticality of the steel column 1 by tightening the nuts 6 with respect to the anchor bolts 5 in such a state. ing.

In the method of using the wedges 4, it is very difficult to improve the vertical accuracy of the steel column 1, and furthermore, a gap 9 is formed between the base plate 2 and the foundation 3 over almost the entire area of the base plate 2. be done. Since this void is very narrow in vertical width, it is hardly expected that the void 9 will be filled with concrete when the lower end of the steel column 1 is solidified with concrete. Therefore, the void 9 remains as it is, and the vertical load is transmitted from the steel column 1 to the foundation 3 only in the periphery of the base plate 2.

In addition, the method of using the mortar mound 7 allows the verticality of the steel column 1 to be adjusted relatively easily, and the space between the base plate 2 and the foundation 3 is filled with concrete that is relatively wide compared to the gap 9. Although the space can be secured, in reality, it is not possible to fill the concrete 8 up to the upward wedge-shaped space above the slope of the mound 7 as shown in the figure. Therefore, a void 9 remains around the mound 7. Even if it is possible to sufficiently pack the concrete 8 around the mound 7 using a work method that ignores efficiency, it is necessary to avoid creating a gap between the base plate 2 and the concrete 8 due to shrinkage as the concrete hardens. In extreme cases, the steel column 1 will be supported only by the mortar mound 7, which has significantly lower compressive strength than concrete.

As described above, with the conventional method, it was not actually possible to support and fix the steel column 1 without leaving a gap between the base plate 2 and the foundation 3. This situation occurs when the vertical load acting on a steel column increases as the building is completed.
This causes sinking and distortion of the steel column 1, leading to cracks in the slabs and walls supported by the steel column 1.

(Means and effects for solving the problems) The present invention proposes a support structure for a steel column that can solve the conventional problems as described above. A cone-shaped body that covers almost the entire lower end of this steel column and whose center part protrudes downward is fixed, and while the protruding tip of this cone-shaped body is placed on the foundation, the area around the lower end of the steel column and the foundation are fixed. The steel frame is held vertically by connecting them with anchor bolts, and the outwardly expanding space between the conical body and the upper surface of the foundation is filled with concrete.

According to the support structure of the present invention, the steel column can be tilted 360 degrees in any direction using the protruding tip of the pyramid as a fulcrum, as in the case of using the conventional mortar mound 7, The verticality of steel columns can be adjusted easily and with high precision. When filling with concrete after fixing with anchor bolts, due to the presence of the cone, the concrete filling space at the bottom of the steel column is diagonal, contrary to the case where the conventional mortar mound 7 is used. This creates a wedge-shaped space that slopes downward, and therefore, it is possible to fill the space between the bottom end of the steel column and the foundation without leaving any gaps by simply flowing concrete toward the center of the bottom of the steel column. In addition, since the concrete is filled into a wedge-shaped space whose upper side slopes diagonally downward toward the back as mentioned above, the concrete can be filled densely and firmly with a wedge effect, making it possible to fill the concrete tightly and firmly, unlike the conventional method. This eliminates the need to create voids that would adversely affect the lower side of the steel column due to shrinkage due to hardening.

(Embodiment) An embodiment of the present invention will be described below based on the attached illustrative drawings. As shown in FIGS. 3 and 4, the lower end of the steel column 1 has a base plate provided with bolt holes 10 around the periphery. 2 is fixed to the base plate 2, and a cone-shaped body 11 as shown in FIG.
is fixed so that it protrudes downward. The conical body 11 is formed from a steel plate, has a width that covers substantially the entire lower end of the steel column 1, and is provided with a flat protruding tip portion 11a.
Also, an air vent hole 11b is provided beside the protruding tip 11a.
is formed.

When the base plate 2 and the conical body 11 are stacked and integrated as described above and the internal space of the conical body 11 is sealed, the base plate 2 also needs an air vent hole. However, as shown in FIG. 6, the base plate 2 fixed to the lower end of the steel column 1 can be omitted by arranging a flange portion 12 with bolt holes 10 from the periphery of the conical body 11. In this case, an auxiliary contact plate 13 for connecting the steel column 1 and the flange portion 12 can also be used together, as shown by the imaginary line in FIG. Further, the conical body 11 is fixed to the lower end of the steel column 1, and a plate with bolt holes may be fixed and protruded in the shape of a brim on the circumferential surface near the lower end of the steel column 1.

Furthermore, the steel column 1 is equipped with an H-shaped steel 14 as shown in FIG.
, the central web 14a of the H-shaped steel 14 is made to protrude so as to come into contact with the inner bottom surface of the conical body 11, and are welded and fixed to each other,
Further, if necessary, auxiliary plates 15 can be interposed and fixed between both sides of the central web 14a, the inner surface of the conical body 11, and the flange portion 12.

A square pipe-shaped steel column 1 and an H-shaped steel 14
However, the present invention is not limited to these, of course. Further, although the pyramid-shaped body 11 is shown as having a pyramidal shape that is easy to manufacture from an iron plate, it may also have a conical shape. Furthermore, although the flat protruding tip portion 11a is integrally formed, it is also possible to form the outer surface of the protruding tip portion into a spherical shape. The cone-shaped body 11 is not limited to being hollow, but may be solid.

In any case, the above-mentioned conical body 11 is attached to the lower end of the steel column 1, and when the steel column 1 is erected, it is pre-constructed with concrete as shown in Fig. 3. On the foundation 3, an anchor bolt 5 protruding from the foundation 3 is attached to the base plate 2.
Alternatively, the steel column 1 is lowered substantially vertically so as to pass through the bolt hole of the flange portion 12, and the protruding tip portion 11a of the conical body 11 is placed on the foundation 3. As a result, the steel column 1 has a 360-degree angle with the protruding tip 11a as a fulcrum.
Since the verticality of the steel column 1 can be tilted in any direction, tighten the nuts 6 that are screwed into each anchor bolt 5 while adjusting the verticality of the steel column 1 with high precision, and if necessary, tighten the nuts 6 to the anchor bolts 5. The steel column 1 is fixed to the foundation 3 by welding.

If the height of the steel column 1 needs to be adjusted, the surface level of the foundation 3 can be adjusted by applying mortar to the area on the foundation 3 where the cone 11 is placed, or the height of the cone 11 can be adjusted. A height adjustment plate of an appropriate thickness can be interposed between the tip 11a and the foundation 3, but as shown in FIG. 16
It is also possible to construct a structure in which the height of the steel column 1 can be adjusted by providing a protruding bolt 16 and adjusting the amount of protrusion of this bolt 16.

If the verticality of the steel column 1 is adjusted as described above and the steel column 1 is fixed to the foundation 3 with the anchor bolts 5 and nuts 6, the conical body 11 and the foundation 3 will be connected as shown in FIG. Concrete 8 is filled without any gaps in the outwardly expanding space formed between the two,
The hardened concrete 8 supports the steel column 1. When filling this concrete 8, the concrete filling space formed between the conical body 11 and the foundation 3 is a downward wedge-shaped space whose upper surface is inclined diagonally downward from the surroundings of the steel column 1. Even without particularly pressing the concrete toward the depths of the space, the concrete 8 can flow into and fill the space below the cone 11 without any gaps just by the horizontal flow force on the foundation 3 due to the gravity of the concrete itself. I can do it. The concrete 8 flowing into the space is densely packed due to the wedge effect, and even if some shrinkage occurs due to hardening, no large gap will be created between the concrete 8 and the bottom surface of the conical body 11. .

(Effects of the Invention) As described above, according to the steel column support structure of the present invention, the vertical adjustment of the steel column is the same as when using the conventional mortar mound called "Manjiyu". It is extremely easy to fill concrete between the bottom end of the steel column and the foundation without any gaps, and it is possible to reliably transfer the vertical load acting on the steel column through the filling concrete. Steel columns can be supported in a state where they can be transmitted to the foundation. Therefore, it is possible to completely eliminate the occurrence of cracks in slabs and walls due to sinking and distortion of steel columns due to gaps remaining between the bottom ends of steel columns and concrete filling. .

In addition, by simply attaching a cone to the lower end of the steel column in advance, there is no need to form the mound on the foundation at the construction site, and the work of erecting the steel column at the construction site can be carried out more efficiently. .

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are side views explaining a conventional example;
3 is a side view of an embodiment of the present invention, FIG. 4 is a bottom view of a steel column, FIG. 5 is a perspective view of a cone, FIGS. 6 and 9 are longitudinal sectional side views showing modified examples, and FIG. FIG. 7 is a perspective view showing the structure of the lower end of the steel column when the steel column is made of H-shaped steel, and FIG. 8 is a longitudinal side view of FIG. 7. 1... Steel column, 2... Base plate, 3... Foundation,
4...Wedge etc., 5...Anchor bolt, 6...Nut, 7
...Motar mound, 8...Filled concrete, 9
...Gap, 10...Bolt hole, 11...Cone, 11a
...Protruding tip portion, 11b...Air vent hole, 12...Flange portion, 14...H-shaped steel, 16...Height adjustment bolt.

Claims (1)

[Claims] 1. A cone-shaped body that covers almost the entire lower end of the steel-frame column and whose central part protrudes downward is fixed to the lower end of the steel column, and the cone-shaped body is placed on the foundation with its protruding tip. A steel frame formed by connecting the lower end of the steel frame and the foundation with anchor bolts to hold the steel frame vertically, and filling the outwardly expanding space between the conical body and the upper surface of the foundation with concrete. Column support structure.