JPH0765322B2 - Steel column base fixing structure for foundation concrete - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention, for example, in a landfill site, by constructing a structure at a time when the stability of the ground is not yet completed, while significantly shortening the construction period, If uneven settlement occurs in the foundation concrete due to variations in the tightness of the buried layer and the settlement of the alluvial clay layer below the buried layer due to unbalanced load, the structure is raised to increase the structure. The present invention relates to a steel column base fixing structure for foundation concrete for carrying out a so-called structure uplifting method capable of keeping the horizontal of the structure.

[Conventional technology]

As a steel column post fixing structure for this type of basic concrete, the one described in Japanese Examined Patent Publication No. 46-17005 is known. FIG. 5 shows the above-mentioned conventional example, in which the right half of the figure shows a state before raising, and the left half of the figure shows a state after finishing raising.

In this steel column support structure, a double nut a is welded near the upper end opening, a fixing pipe d filled with a wooden plug b and filled with grease c is added to the basic concrete e, and 4 to 8 per steel column. The upper end sides of the embedded vaults f that are embedded about this number and screwed into the double nut a are inserted into the base plates h of the steel columns g, respectively, and the base plates h are always screwed into the embedded vaults nuts i, j At the time of raising, the embedded vault f is rotated to loosen the nut i while the bolt k is attached to the base plate h.
The height is raised to a desired height by a padding tool (not shown) that is tightly connected via the.

[Problems to be solved by the invention]

According to the above-mentioned conventional example, since the structure can be raised in parallel with the subsidence of the ground, the construction of the structure can be started early after the landfill construction, and the construction period can be significantly shortened. There was room for improvement. That is, (1) the work of welding the double nut a inside the fixing pipe d in a state where the screw grooves are matched is troublesome, and the base plate h of the steel column g is fixed to the basic concrete e by the embedded vault f. Therefore, 4 per steel column
~ 8 embedded vaults f and fixing pipes d are required,
Ensuring the accuracy of the embedding position of the fixing pipe d and the verticality is so troublesome that the workability is poor as a whole.

(2) At the time of raising, all the embedded vaults f screwed to the double nuts a of the fixing pipes d must be pulled out to a desired height in advance, and the workability at the time of raising is poor.

(3) Since each embedded vault f is used as a guide rail for sliding to raise the column base, the pace plate h
When the edge of the bolt hole of # 1 makes strong contact with the embedded vault f,
The embedded vault f bends, or the embedded vault f
In some cases, the screw threads may hinder smooth lifting, or some of the threads may be crushed to make it difficult to rotate the nut j that supports the lower surface of the pace plate h.

In view of the above-mentioned conventional drawbacks, the present invention is to provide a steel column base fixing structure for basic concrete which has good workability and can easily and quickly perform a raising operation.

[Means for solving problems]

The feature of the steel column base fixing structure for the foundation concrete according to the present invention is that one slide column body is provided on the upper surface of the foundation concrete for each steel column column, while the column base section of the steel column column has the above-mentioned column body. An annular base plate that is fitted in a vertically movable state, and a ring that can be switched between a state in which the column is clamped and fixed and a state in which the clamp is loosened, and a state in which the ring is loosened Then, a raising tool interposed between the basic concrete and the floor beam connected to the steel column is configured to raise the steel column by using the column body as a guide.

[Action]

According to the above configuration, when the steel frame is built, the annular base plate is fitted over the column body, so that the steel frame column is self-supporting on the foundation concrete.

Although there is a certain amount of clearance between the outer peripheral surface of the column and the hole edge of the annular base plate, the horizontal movement of the column base is restrained by tightening and fixing the ring to the column.

When lifting the steel pillar by loosening the tightening by the ring, the pillar can be used as a guide to smoothly lift.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 is a foundation concrete of a floating foundation system, which has a rectangular box shape composed of a foundation slab 1a and a foundation beam 1b, and cracks in the foundation slab 1a and the foundation beam 1b are caused by a bending moment generated due to uneven settlement. To a minimum,
So that the foundation slab 1a and foundation beam 1b behave as elastic bodies,
Prestress is introduced by the PC steel material embedded in them.

On the upper surface of the foundation beam 1b of the foundation concrete 1, one slide column body 2 is provided projecting at each steel frame column construction planned position for each steel frame column. This column body 2 is provided with sufficient strength so that even one column does not hinder the fixation of the column base. Specifically, the upper end side is exposed to the foundation beam 1b of the foundation concrete 1. It is composed of a steel pipe 2a having a proper diameter and embedded in a state, and a concrete 2b filled in the steel pipe 2a.

Reference numeral 3 denotes a square-pipe-shaped steel frame column, and an annular base plate 4 having a circular hole slightly larger than the diameter of the column 2 is welded to its column base so as to be vertically movable with respect to the column 2. It has been fitted into a simple state. In addition, a ring 5 made of a steel plate is provided at a position above the base plate 4 on the column base so as to be able to switch between a state where the column body 2 is fastened and fixed and a state where the fastening is loosened.

As shown in FIG. 2 and FIG. 3, the ring 5 is composed of four members provided with bolting protrusions 6b at both ends of the arc-shaped plate portion 6a. The protruding pieces 6b are radially arranged on the upper surface of the base plate 4 and welded 4
The bolts 8a and the nuts 8b are fastened and fixed to the bracket 7 of one sheet, and the bolts 8a and the nuts 8b are loosened at any one of the positions so that the tightened and fixed state of the ring 5 with respect to the pillar 2 is released.

The bolt hole of the bracket 7 is formed slightly larger than the diameter of the bolt 8a. At the positions corresponding to the brackets 7 of the steel frame column 3, there are formed openings 9 for operating the bolts 8a and nuts 8b by inserting tools such as wrenches.

In FIG. 1, 10 is a floor beam on the first floor connected to the steel column 3, and 11 is a floor, which is constructed by placing concrete on a deck plate and placing concrete.

According to the above configuration, by fitting the base plate 4 onto the columnar body 2, the steel frame column 3 is on the foundation beam 1b of the concrete foundation 1 (specifically, on the level-adjusted mortar).
Since it is self-supporting, it is easy and safe to construct a steel frame.

Then, at all times, the base plate 4 of the steel column 3 is supported by the foundation beam 1b of the concrete foundation 1, and the ring 5 is clamped and fixed to the column body 2 to restrain the horizontal movement of the steel column 3. As shown in FIG. 4 (a), a padding tool 12 such as a hydraulic jack is interposed between the foundation beam 1b of the foundation concrete 1 and the floor beam 10 of the first floor which is connected to the steel column 3 when raising. Then, in a state where the tightening by the ring 5 is loosened, the steel pillar 3 is raised to the desired height by the raising tool 12, and as shown in FIG. After installing the liner material 13, remove the raising tool 12 and remove the base plate 4
Is supported by the liner material 13, and the ring 5 is retightened in this state to restrain the movement in the horizontal direction.

According to the above-mentioned column base fixing structure, even if the foundation concrete 1 is tilted due to uneven settlement, the column base can be raised to keep the upper construction part horizontal, and consolidation settlement like landfill site is expected. It is suitable for early construction of airport buildings, hangars and other buildings on the ground.

If there is no large working space under the floor beam 10,
As shown in FIG. 1, it is desirable to form through holes 14 that serve as passages for carrying the raising tool 12 in the required places of the foundation beam 1b that divides the bottom slab 1a into vertical and horizontal lattices. .
Further, a plurality of projecting pieces that are close to the outer peripheral surface of the annular plate or the column body 2 having a hole having a size substantially equal to the round hole of the base plate 4 at a position inside the steel frame column 3 and at an appropriate distance above the base plate 4. May be welded to prevent the steel frame pillar 3 from resting against the pillar body 2.

[Advantages of the Invention] The present invention has the following advantages due to the above-described configuration.

Since one slide column for each steel column is erected on the concrete foundation and the column is used as a guide to raise the steel column, it has a double nut as described at the beginning. A conventional example in which 4 to 8 fixing pipes are embedded in the basic concrete per steel column, and the embedded vault that is screwed with the double nut of each fixing pipe is used as a guide to raise the steel column. The structure is simpler and the pillars can be easily constructed more accurately, and by fitting the annular base plate of the steel pillar to the pillar, the steel pillar becomes self-supporting on the foundation concrete. Can be easily and safely constructed and has good workability.

When raising the structure, the fixed state of the column base can be released by simply loosening the ring, and there is no need to pull up many embedded vaults to the desired height in advance as in the conventional example. The workability of raising is good, and since one column is used as a guide for raising, the bending of the embedded vault, catching on the thread of the embedded vault, and crushing of the thread occur as in the past. Without fear, it is possible to smoothly raise the steel column (bulk of the structure).

[Brief description of drawings]

1 to 4 (a) and (b) show an embodiment of the present invention, and FIG. 1 is a schematic cross-sectional view showing a steel column base fixing structure for foundation concrete of a floating foundation system,
The figure is a partially cutaway perspective view of the main part, FIG. 3 is a cross-sectional plan view of the main part, and FIGS. 4 (a) and 4 (b) are vertical side views of the main part for explaining the raising procedure. FIG. 5 is a vertical sectional side view showing a conventional example. 1 ... Foundation concrete, 2 ... Slide column, 3 ...
… Steel columns, 4 …… Base plate, 5… Rings, 10…
… Floor beams, 12… Lifting tools.

Claims (2)

[Claims] 1. A slide column body per steel column is projected on the upper surface of the foundation concrete, while a column base of the steel column is vertically movable with respect to the column body. Provided with an annular base plate fitted, and a ring capable of switching between a state of tightening and fixing to the column body and a state of loosening the tightening, and in a state of loosening the tightening by the ring, it is coupled to the foundation concrete and the steel column. A structure for fixing a steel column base to a foundation concrete, characterized in that it is configured so that a steel frame column can be raised using the column body as a guide by a raising tool interposed between the steel frame and the floor beam. 2. The slide column body is composed of a steel pipe having a circular cross section embedded in the basic concrete in a state where the upper end side is exposed, and concrete filled inside the steel pipe. A steel-framed column base fixing structure for foundation concrete according to claim 1.