JP2747566B2 - Construction method of straight pillar - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a basement pillar, which is a foundation of a pillar, in the ground, mainly when a basement structure of a building is to be constructed by a reverse hitting method. More specifically, the present invention relates to a construction method for constructing a straight pillar having a high accuracy of construction that enables the construction of a steel column-beam frame.

2. Description of the Related Art Conventionally, a reverse striking method has been widely practiced, and construction of a straight pillar required for the method has also been widely practiced.

In the construction of a timber pillar, it is important to increase the accuracy of the installation. Especially in recent years, there is a tendency to use timber columns as steel framed beams. In addition, since it is necessary to incorporate a large amount of factory processing, it is required that the assembling accuracy of the beam-column frame be reduced to about 1/1000.

Conventionally, a method of constructing a straight pillar generally practiced is a method in which concrete is poured into the bottom of a hole of a pile hole, and then a steel frame of a straight pillar is inserted into the pile hole and pushed into the concrete. However, it is often difficult to correctly install the steel column at a predetermined position depending on the shape, the size, and the length of the steel column.

In this regard, the construction method of a straight pillar described in Japanese Patent Publication No. 54-12721 discloses a method in which a measuring pipe is inserted into a pile hole into which a stand pipe is inserted so that its axis is concentric with the pillar core. Using a measuring instrument attached to the lower end of this measuring pipe, measure the distance in two horizontal directions between the inner peripheral surface of the stand pipe and the measuring pipe at least at two places above and below the pile hole, and find the structure to be erected at the upper and lower measuring points. The horizontal distance between the outer peripheral surface of the column steel frame and the inner peripheral surface of the stand pipe is obtained, and a spacer equal to the horizontal distance is fixed to the upper and lower portions of the columnar steel frame in advance, and then the framed columnar steel frame is inserted into the pile hole. Then, the peripheral side surface of the steel column is pressed by a pressing member such as a jack so that each spacer comes into contact with the inner peripheral surface of the measuring point of the stand pipe. It is designed to fix the legs.

Problems to be Solved by the Present Invention All the work to improve the accuracy of setting up a timber pillar that reaches a depth of 30 m underground must be performed on the ground. A major problem is that the actual accuracy can only be grasped after excavation of the ground, and at that time it cannot be corrected late.

It is clear that the construction method described in the above-mentioned gazette was also a matter of struggling to improve the accuracy of setting the timber pillar,
First of all, the method is to proceed with all the subsequent work on the premise of the horizontal distance measured by the measuring pipe and measuring instrument at first, so the process is roughly divided into two stages, the measuring process and the real process such as the insertion of steel columns. It takes time and effort. In addition, it is impossible to confirm whether or not the insertion of the steel columns is carried out in the same manner as the specifications of the measurement by the measuring pipe and the measuring instrument, that is, it is not based on real-time measurement, so that the reliability is lacking. If the insertion of the steel column is not the same as the specification of the measurement, it is clear that the previously performed measurement lacks significance.

Secondly, on-site spacers having a length equal to the measured horizontal distance must be fixedly attached to the steel column and projecting therefrom, thereby increasing on-site work. In addition, since a steel pillar is inserted into the pile hole after a pressing member such as a jack is attached, it is difficult to perform the insertion work because the spacer or the jack acts as an obstacle to hit the hole wall. If the spacer or the like hits the inner surface of the stand pipe and damages or deforms the inner surface, the effectiveness of the previously performed measurement is impaired. Conversely, the spacer may be bent or the position of the pressing member may be shifted, so that it is difficult to expect the reliability of the installation accuracy.

Third, it is very uneconomical because the spacers and jacks cannot be collected.

Fourth, although the tip position of a steel column is likely to shift due to the concrete's flowing pressure when concrete is poured, there is no way to confirm and correct such a shift. Poor assurance of accurate installation accuracy or reliability.

Therefore, an object of the present invention is to enable real-time measurement and correction of position errors and inclinations and the like based correction even after a steel column is erected in a pile hole, and furthermore, during and during concrete casting to the bottom of the hole. The object of the present invention is to provide a construction method of a straight pole which can be measured and corrected later to achieve a high installation accuracy, and the inclinometer and the correction jack device have been improved to a completely recoverable configuration.

Means for Solving the Problems As a means for solving the above-mentioned problems of the prior art, a method of constructing a straight pillar according to the present invention uses a stand pipe 2 as shown in a preferred embodiment in the drawings. After excavating the pile hole 1, a stand 8 is installed at the upper end of the stand pipe 2, and a correction jack device 9 mainly composed of a ring is suspended and prepared at a position as close to the lower end as possible in the stand pipe 2; A steel column 10 with a clinometer 15 attached to a position near the lower end is erected in the pile hole 1, and the upper end of the columnar steel frame 10 is attached to the base 8.
And the correction jack device 9 corrects the position and inclination of the steel column 10 so that the inclination of the steel column 10 measured by the inclinometer 15 becomes zero. After the stage and the correction and positioning of the construction position of the steel column 10 are completed, concrete 16 is poured into the bottom of the hole, and the change in the position of the steel column 10 during and after the concrete is placed. Correcting the position and the inclination of the steel columns with the correction jack device 9 after confirming them with the inclinometer 10 and then performing concrete curing to fix the column pedestals.

According to the construction method of the present invention, the modified jack device 9 is also provided with a required number of jacks 9b on a ring 9a having a diameter sufficiently larger than the outer diameter of the steel column 10 and smaller than the inner diameter of the stand pipe 2. The modified jack device 9 is attached to a predetermined position in the stand pipe 2 by using a chain 12 fixed to a ring 9a in a radial direction and attached in an up-and-down configuration (FIGS. 9 and 10). When the jacks 9b ... are turned down, the steel columns 10 are erected in the ring 9a, and then the ropes 11 previously fixed to the jacks 9b are pulled to bring the jacks 9b ... into a substantially horizontal posture. To correct the position and inclination of the steel column 10 and after curing the concrete 16 at the bottom of the hole, lift the modified jack device 9 to the ground with a chain 12 and collect it. The inclinometer 15 includes a plurality of electromagnets 17. Steel columns At least two of them are provided at a position higher than the top end of the concrete 16 to be cast near the tip of the hole 10 at the bottom of the hole, and at two positions perpendicular to the steel column 10 in plan view (the eleventh direction). , 12
Figure), each inclinometer 15 is connected to a record indicator on the ground to measure and display the inclination of the steel column 10 in real time. After curing the concrete 16 at the bottom of the hole, the electromagnet 17 is demagnetized. Pulling up and collecting the inclinometer 15 to the ground with the rope 18 fixed, the tip of the steel column 10 and the beam 10 are equally distributed in the radial direction when the steel column 10 is viewed in the plane direction. A plurality of wires 20 are fastened one by one to a plurality of locations (FIG. 6).
The other end of 20 is secured on the ground, and the correction of the position and inclination of the steel column 10 measured by the inclinometer 15 is performed by pulling the wire 20 on the ground.

Action The trussed steel column 10 can be provided with a trummy tube 21 before installation (FIG. 7), or a gusset plate for beam steel connection can be pre-fabricated.

After the building is installed, the inclination of the steel frame steel column 10 whose upper end is supported at the center (column center position) of the pile hole 1 by the gantry 8 is measured by an inclinometer 15 attached to a position closer to the lower end thereof. The installation accuracy of the steel frame 10 can be accurately grasped in real time while staying on the ground. Moreover, based on the above measurement, the position and inclination of the steel column 10 can be corrected in real time by operating the correction jack device 9 or the wire 20. Correction work can be carried out whenever necessary, not only immediately after construction but also while the concrete 16 is being poured into the bottom of the hole and while the concrete 16 has not yet set.

Each jack 9b, which is attached to the ring 9a so as to lie down (hang down) by its own weight, does not interfere with the construction of the steel column 10 in a state where the jack 9b is laid down. After the steel frame 10 is installed, when the rope 11 previously fixed to each jack 9b is pulled on the ground, the jack 9b stands up in a horizontal posture. When the jack 9b is activated in this horizontal posture, a reaction force is applied to the inner peripheral surface of the stand pipe 2 to push and move the steel column 10 to correct the position and the inclination. When the piston rod 9g of the jack 9b is contracted after use, the restrained relationship between the steel frame 10 and the stand pipe 2 is released, and the jack 9b lays down by its own weight. Therefore Qian
The modified jack device 9 suspended at 12 can be lifted to the ground and collected.

Since the inclinometer 15 is attached to the steel pole 10 with the attraction force of the electromagnets 17, the inclinometer 15 is easily released from the steel frame 10 when the electromagnet 17 is demagnetized. Therefore, it can be lifted to the ground with the rope 18 and collected.

Embodiment Next, the illustrated embodiment of the present invention will be described.

FIG. 1 to FIG. 8 show flowcharts of main steps of the straight pillar construction method of the present invention. First, FIGS. 1 and 2 show, for example, excavation of a pile hole 1 and pushing of a stand pipe 2 by an excavator 3 of a reverse construction method, and further, enlarging (extending of a bottom) excavation of a hole bottom by an excavating machine 4. The following shows the stage. Pile 1 is usually excavated to a depth of about 33 m underground with a vertical accuracy of about 1/200. In FIG. 3, a hole wall measuring machine 5 is installed at the upper end of the stand pipe 2, a sensor cable 6 is dropped at the center of the pile hole 1, and a hole wall measurement is performed by a hole wall sensor 7 attached to the tip of the cable 6. 2 shows a stage of conducting the survey and investigating the side tendency of the pile hole 1.

Next, FIG. 4 shows a stand 8 attached to the upper end of the stand pipe 2.
Is shown, and the correction jack device 9 is suspended and prepared at a position as close to the lower end as possible in the stand pipe 2. Details of the configuration of this modified jack device 9 are shown in FIGS. 9 and 10, and the outer diameter is about 1.6 m or 1.8 m and the U-shaped cross section is for the stand pipe 2 having an inner diameter of about 1.8 m or 2 m. The ring 9a has four hydraulic jacks 9b…
Are arranged in radial directions in four perpendicular directions. Each hydraulic jack 9b has a support pin 9d of a bracket 9c fixed inside the ring 9a and a jack holder.
It is attached in a long groove 9f provided near the base end of 9e so that it can be raised and lowered. Therefore, hydraulic jack 9b
Usually falls down (hangs down) as shown by the two-dot chain line in FIG. 9 due to its own weight. For this reason, one end of the rope 11 is fixed to the free end of the hydraulic jack 9b, and the other end of the rope 11 is secured on the ground. Can be erected. When each hydraulic jack 9b in the horizontal posture is driven, the piston rod 9g is extended and abuts against the inner surface of the stand pipe 2 to take a reaction force, and pushes and moves the steel column 10 at the center to correct the position. One end of the chain 12 is fixed to the ring 9a at four positions equally dividing the circumference as shown in FIG. 10, and the other end is secured on the ground so that the modified jack device 9 is mounted on the stand pipe 2 Is suspended at a predetermined position in the inside. Therefore, the modified jack device 9 is
Can be lifted to the ground again and collected.

Next, FIG. 5 shows a stage in the middle of the construction of a steel column 10 having a length of about 26 m into the pile hole 1, and FIG.
This shows a stage in which the upper end of 10 is centered on the center of the pile hole 1 by the gantry 8 and fixed and supported. Steel columns
10 is installed vertically with a crane or the like using a yatco 25 and a torbasser 26 (FIG. 5). The steel column 10 is provided with a shear connector 28 protruding at a tip end as a factory process, or a gusset plate or the like for connecting steel beams. Prior to the construction at the site, the site is inclined at a position near the lower end of the steel column 10 and slightly above the top of the concrete 16 to be cast at the bottom of the hole as shown in FIG. A total of 15 are attached. Further, if necessary, one wire 20 (FIG. 6) may be provided at the tip of the steel column 10 at a position evenly divided into four, six or eight equal parts when viewed in plan. ) Is fixed, the building is performed, and the other end of the wire 20 is secured on the ground. As shown in detail in FIGS. 11 and 12, the attached form of the inclinometer 15 is such that the straight pillar steel frame 10 having a square shape (or a circular shape, an H shape, or the like) is flat as shown in FIG. Two are provided at positions in two orthogonal directions when viewed from the viewpoint. On the upper part of the well-known inclinometer 15 having a thin and long cylindrical shape, two arms 19, 19
And two block-like electromagnets 17, 17 each of which is provided in a symmetrical arrangement. Also, an electromagnet 17 in the form of a single block is attached to the lower part by protruding one arm 19. Therefore, the inclinometer
15 is pressed against a predetermined position of the steel column 10 in a predetermined manner,
By exciting each of the electromagnets 17 by the changeover switch, the inclinometer 15 can be positioned and fixed (attached) immediately.
One end of a rope 18 is fixed to the upper part of the inclinometer 15,
When the steel column 10 is erected, the other ends of the rope 18 and the electric cable 24 are secured on the ground. Electrical cables 24
Is connected to a ground indicator (not shown).

The details of the structure of the gantry 8 for supporting the upper part of the steel pole 10 erected in the pile hole 1 are as shown in FIGS. 13 and 14. Two receiving beams 30, 30 are prepared on the gantry 8, and the verticality of the steel frame 10 is confirmed by the traverser 26 immediately before the installation of the steel column 10 is completed. Then, the receiving beams 30, 30 are moved directly below the angle 31 of the yatco 25, and are fixed to the gantry 8 by bolts, and then the angles 31, 31 is received, and the steel column steel frame 10 is supported at the column center position. By operating the jack 32, the height position of the steel column 10 is finely adjusted. Thereafter, the corresponding hydraulic jack 9b of the correction jack device 9 is controlled from the ground through the control device so that the displacement or inclination of the steel pole 10 measured by the two lower inclinometers 15, 15 becomes zero. And make corrections.

After that, a mass 33 is installed on the upper part of the trummy tube 21 which has been built in front of the steel column 10 and concrete 16 is poured on the bottom of the hole (FIG. 7). During this concrete placement and after the concrete 16 is cast, until the concrete 16 solidifies, the displacement and inclination of the steel columns 10 are continuously measured by the inclinometer 15, and the displacement and inclination may occur. Immediately, the correction jack device 9 is controlled, or if necessary, the correction is performed by pulling the wire 20 from the ground in each direction. The concrete 16 is cast at a depth of about 5 to 6 m at the bottom of the hole, and the lower end of the steel column 10 is buried at a sufficient depth. Therefore, when the curing of the concrete 16 is completed, the solid fixation of the column base is completed.

After the concrete 16 has been cured, the hydraulic jack 9b of the correction jack device 9 is first loosened and removed, and then lifted to the ground by the chain 12 and collected. Next, inclinometer 15 electromagnet
Degauss 17 and pull it up to the ground with rope 18 to collect.

Finally, the hopper 40 is attached to the upper end of the stand pipe 2 and the gravel 41 is put in so that the pile hole 1 is backfilled (FIG. 8) to complete the straight pillar.

Advantageous Effects of the Present Invention As described in detail in connection with the embodiments above, the method of constructing a straight pillar according to the present invention is a concrete 16 The installation accuracy can be continuously measured in real time with the inclinometer 15 until the solidification is completed, and the correction by the correction jack device 9 or the wire 20 can be performed. A perfectly grasped construction is performed.
Therefore, it is possible to easily carry out the reverse hitting method using a steel beam-column frame which employs factory processing.

Further, the modified jack device 9 and the inclinometer 15, which are auxiliary devices for construction, can be completely recovered and diverted, so that economic efficiency is high.

Furthermore, the construction method of the present invention also contributes to shortening the construction period because the installation of the steel columns 10 and the placing of concrete at the bottom of the hole and the confirmation of the accuracy of the installation and the correction work are performed in parallel in real time. It is.

[Brief description of the drawings]

FIGS. 1 to 8 are essential process diagrams of the straight-column construction method according to the present invention, and FIGS. 9 and 10 are cross-sectional views and plan views showing a partially enlarged use state of the modified jack device. Figures 11 and 12
The figures are a plan view and a front view showing a state in which the inclinometer is attached to a steel frame steel column, and FIGS. 13 and 14 are a plan view and a sectional view of a gantry portion. … Pile hole 8… Stand, 9a …… Ring 9… Modified jack device, 15… Inclinometer 10… Steel column steel frame, 16… Concrete 9b… Hydraulic jack, 12… Chain 11… Rope , 17 ... electromagnet 20 ... wire

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Norio Kosaka 8-21-1, Ginza, Chuo-ku, Tokyo Inside Takenaka Corporation Tokyo Main Office (72) Inventor Isao Tsutsui 8-2-1-1, Ginza, Chuo-ku, Tokyo No. Takenaka Corporation Tokyo Main Store (72) Inventor Masato Sakai 8-21-1, Ginza, Chuo-ku, Tokyo In-house Takenaka Corporation Tokyo Main Store (72) Inventor Masanobu Sato 8-21 Ginza, Chuo-ku, Tokyo No. 1 Inside Takenaka Corporation Tokyo Main Store (72) Inventor Masanori Ide 8-21-1, Ginza, Chuo-ku, Tokyo Inside Tokyo Main Store Takenaka Corporation (56) References JP-A-52-48207 (JP) , A) JP-A-62-133255 (JP, A)

Claims (4)

(57) [Claims] After excavating a pile hole using a standpipe, a gantry is installed at an upper end of the standpipe, and a correction jack device mainly including a ring is hung as close to the lower end as possible in the standpipe. And a step of preparing, a steel pillar with a tiltmeter attached to a position near the lower end is erected in the pile hole, the upper end of the steel pillar is supported at the center of the pile hole by the gantry, and the tiltmeter is used. Correcting the position and the inclination of the steel column by the correction jack device so that the measured inclination of the steel column is zero, and correcting and positioning the erected position of the steel column. Later, concrete was poured into the bottom of the hole, and the change in the position of the steel columns during and after the concrete placement was checked with an inclinometer, and the position and inclination of the steel columns were corrected using a correction jack device. From con A method for fixing a columnar leg portion performs discrete curing, construction method of 構真 pillar, characterized in that more made. 2. The modified jack device according to claim 1, wherein the required number of jacks are radially oriented on a ring having a diameter sufficiently larger than the outer diameter of the steel column and smaller than the inner diameter of the stand pipe, and can be raised and lowered. This modified jack device is hung to a predetermined position in the stand pipe using a chain fixed to the ring, and each jack is turned down and a steel column is erected in the ring with each jack turned down. After that, pull the rope fixed to each jack in advance to raise each jack in a substantially horizontal position, correct the position and inclination of the steel column, correct the concrete at the bottom of the hole, and fix it with a chain. The construction method of a straight pillar according to claim 1, wherein the apparatus is collected on the ground. 3. The inclinometer is located near the lower end of the steel framed column by a plurality of electromagnets and higher than the top end of the concrete cast at the bottom of the hole. At least two of them are attached at two positions at right angles, and each inclinometer is connected to a record indicator on the ground to measure and display the inclination of the steel column in real time, demagnetize the electromagnet after curing the concrete at the bottom of the hole, 2. The method of claim 1, wherein the inclinometer is collected on the ground using a rope that is fixed to the inclinometer in advance. 4. A plurality of wires are fixed to a plurality of wires, one at a time, at a lower end portion of a right-angled steel frame and at a plurality of positions equally distributed in a radial direction when the same-type steel column is viewed in a plane direction. 2. The configuration according to claim 1, wherein the other end is secured on the ground, and the correction of the position and the inclination of the steel frame column measured by the inclinometer is performed by pulling the wire. Pillar construction method.