JPH03295931A - Construction method for frame straight pillar - Google Patents

Abstract

PURPOSE:To improve the installation precision by measuring the erection precision continuously up to the solidification of the concrete laid into a hole bottom part after the erection of a frame straight pillar iron frame by an inclination meter and carrying out correction by a correcting jack device, after the erection of a frame straight pillar iron frame. CONSTITUTION:After a pile hole 1 is excavated by using a stand pipe 2, a correcting jack device 9 is suspended into the pipe 2. Then, a structural straight pillar iron frame 10 having an inclination meter 15 at the lower edge is erected into the pile hole 1, and the upper edge of the iron frame 10 is supported at the center part of the pile hole 1 by a rack base 8. Then, the position and tilt of the iron frame 10 are corrected by a jack device 9 so that the tilt of the iron frame 10 which is measured by the inclination meter 15 becomes zero. Concrete is laid into the hole bottom part, and the change of the position of the iron frame 10 during and after laying is confirmed by the inclination meter 15, and the position and tilt of the iron frame 10 are corrected. Further, concrete is cured to fix a pillar leg part.

Description

[Detailed Description of the Invention] Industrial Application Field This invention mainly relates to a method of constructing structural pillars, which are used as the foundations of columns, underground when constructing the underground floor structure of a building using the reverse casting method. More specifically, we will develop a construction method for constructing structural columns with high construction precision to the extent that it will be possible to construct a steel column-beam structure.

BACKGROUND OF THE INVENTION Conventionally, the reverse casting method has been widely practiced, and the construction of structural pillars required for this method has also been widely practiced.

When constructing structural pillars, it is important to improve their erection accuracy. Particularly recently, there has been a trend to implement structural pillars as steel-framed column-beam structures. Furthermore, due to the need to incorporate many factory processes, it is desired that the assembly accuracy of the column-beam frame be within about 1/1000, so there is an increasing need to improve the erection accuracy of the structural columns.

A conventional method for constructing structural pillars is to place concrete at the bottom of a pile hole, then insert a structural pillar steel frame into the pile hole and push it into the concrete. However, depending on the shape, external dimensions, and length of the structural column steel frame, it is often difficult to correctly install it in a predetermined position.

In this regard, the method for constructing structural pillars described in Japanese Patent Publication No. 54-12721 involves inserting a measuring pipe into a pile hole into which a stand pipe has been inserted so that its axis is concentric with the pillar core.
Using a measuring instrument attached to the lower end of this measuring tube, measure the distance in two horizontal directions between the inner circumferential surface of the standpipe and the measuring tube at at least two locations above and below the pile hole, and then measure the distances in two horizontal directions between the inner peripheral surface of the standpipe and the measuring tube at at least two locations above and below the pile hole. Determine the horizontal distance between the outer peripheral surface of the steel frame and the inner peripheral surface of the standpipe, and after fixing spacers equal to the horizontal distance to the upper and lower parts of the structural column steel frame in advance, insert this structural column steel frame into the pile hole. , press the peripheral side of the structural column steel frame with a rigid pressing member to bring each spacer into contact with the inner circumferential surface of the measurement point of the stand pipe, and in this state concrete is poured at the bottom of the hole to tighten the column. It is designed to fix the legs.

Problems to be Solved by the Invention Work to improve the accuracy of erection of structural pillars that extend to a depth of 30 meters underground must be performed entirely above ground.

In addition, the actual accuracy can only be determined after the preparation of the ground material.
The big problem is that by then it's already too late to make corrections.

It is clear that the construction method described in the above-mentioned gazette was a result of efforts taken to improve the accuracy of erection of the main pillars, but firstly, the subsequent construction method was based on the premise of the horizontal distance measured by the measuring pipe and measuring instrument. Since it is a method that proceeds with all construction, the process is roughly divided into two stages: the measurement process and the actual process such as inserting the structural column steel frame, which takes time and effort. Moreover, it is impossible to confirm whether the insertion of the structural column steel frame is carried out in accordance with the specifications of the measurement by the measuring pipe and the measuring instrument, that is, it is not based on real-time measurement, and therefore lacks reliability. It is clear that if the insertion of the structural column steel frame is not the same as the measurement specifications, the measurements made in advance would be meaningless.

Second, a spacer with a length equal to the measured horizontal distance must be fixed and protruded from the structural column steel frame on site, which increases the amount of on-site work. Moreover, since the method involves inserting the structural column steel frame into the pile hole with a pressing member such as a jack attached, the spacers and jacks become obstacles that catch on the hole wall, making it difficult to perform the insertion work. If the spacer or the like hits the inner surface of the stand vibe and damages or deforms the inner surface, the effectiveness of the measurements made in advance will be impaired. On the contrary, there is a high possibility that the spacer may be bent or the position of the pressing member may be shifted, so it is difficult to ensure reliability of construction accuracy.

Thirdly, it is very uneconomical because the spacers and jacks cannot be recovered.

Fourthly, even though the tip position of the structural column steel frame tends to shift due to the flow pressure of concrete when concrete is poured, this method does not have a means to recognize and correct such positional shift, so the final There is insufficient guarantee or reliability of construction accuracy.

Therefore, the purpose of the present invention is to measure positional errors and inclinations in real time even after the structural column steel frame is erected into the pile hole.
Furthermore, measurements and corrections can be made during and after pouring concrete at the bottom of the hole, achieving high construction accuracy.Also, the inclinometer and correction jacking device can be completely recovered. The purpose of this invention is to provide an improved construction method for structural pillars.

Means for Solving the Problems As a means for solving the problems of the above-mentioned prior art, the method for constructing a structural pillar according to the present invention uses a stand vibe 2, as a preferred embodiment is shown in the drawings. After excavating the pile hole 1, a stage 8 is installed at the upper end of the stand vibe 2, and a correction jacking device 9 mainly consisting of a ring is suspended and prepared at a position as close to the bottom end of the stand vibe 2 as possible; A structural pillar steel frame 10 with an inclinometer 15 attached near the lower end is erected in the pile hole 1, and the upper end of the structural pillar steel frame 1° is supported at the center of the pile hole 1 by the mount 8. Inclinometer 1
The structural column steel frame 1 is adjusted by the correction jacking device l19 so that the inclination of the structural column steel frame 10 measured by 5 becomes zero.
After correcting the position and inclination of the structural column steel frame 10, and correcting and positioning the structural column steel frame 10, concrete 16 is poured at the bottom of the hole, and the structure is maintained during and after the concrete pouring. Changes in the position of the main column steel frame 10 are also confirmed with the inclinometer 10, and the position and inclination of the main column steel frame are corrected using the correction device E9, and then concrete curing is performed and the column base is fixed; It is characterized by becoming.

In addition, in the construction method of the present invention, the correction jacking device 9 has a required number of jacks 9b on a ring 9a having a diameter sufficiently larger than the external dimension of the structural pillar steel frame 10 and smaller than the inner diameter of the stand vibe 2. The corrective jacking device 9 is attached to a predetermined position in the stand vibe 2 using a chain 12 that is properly attached to the ring 9a (Fig. 9.10). hang it to,
With each jack 9b facing down, the same ring 9
After that, the structural column steel frame 10 is erected into the interior a, and then the rows 111 fixed in advance to each jack 9b are pulled to raise each jack 9b to a substantially horizontal position, and the position of the structural column steel frame 10 is adjusted. After correcting the inclination and curing the concrete 16 at the bottom of the hole, the correction jacking device 9 is raised to the ground using the chain 12 and recovered.
11. At least two pieces are attached near the tip of the hole and higher than the top of the concrete 16 poured at the bottom of the hole, and at two positions perpendicular to the structural column steel frame 10 when viewed from above. (Fig. 12), each inclinometer 15 is connected to a record display meter on the ground to measure and display the inclination of the structural column steel frame 10 in real time. After curing the concrete 16 at the bottom of the hole, the electromagnet 17 is demagnetized and the inclinometer is connected in advance. Row 1 which is fixed at 15
At step 18, the inclinometer 15 is raised to the ground and recovered, and one inclinometer 15 is placed at the tip of the main pillar steel frame 10 of the structure, one at each of multiple locations evenly distributed in the radial direction when looking at the main pillar steel frame 10 in the plane direction. The other end of the wire 20 is secured on the ground (Fig. 6), and the position and inclination of the structural column steel frame 10 measured by the inclinometer 15 can be corrected by fixing the wire 20 on the ground (Fig. 6). To be done by pulling with
Each has its own characteristics.

The tremie pipe 21 (Fig. 7) can be attached to the true column steel frame 0 before erection (Fig. 7), or the gauze plate for joining the beam steel frame can be installed in advance at the factory.

After construction, the inclination of the structural column steel frame 10, whose upper end is supported by the frame 8 at the center of the pile hole 1 (column core position), is measured with the inclinometer 15 attached to the lower end position. The erection accuracy of steel frame 10 can be confirmed accurately in real time while on the ground using i! I can grab it. Moreover, based on the above measurements, the position and inclination of the structural column steel frame 10 can be corrected in real time by operating the correction jacking device 9 or the wire 20. 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 hardened yet, correction work can be carried out whenever necessary.

The jacks 9b, which are attached to the ring 9a so as to lie down (hang) under their own weight, do not pose any hindrance because the structural column steel frame 10 is erected while they are lying down. After the steel frame 10 is erected, if the rope 11, which is attached to each jack 9b, is pulled on the ground,
The jack 9b stands up in a horizontal position. When the jack 9b is activated in this horizontal position, a reaction force is applied to the inner circumferential surface of the stand vibe 2 to push and move the structural column steel frame 10, thereby correcting the position and inclination. When the piston rod 9g of the jack 9b is contracted after use, the restraint between the steel frame 1O and the stand vibe 2 is released, and the jack 9b is laid down by its own weight. Therefore, the correction jack device 9 suspended by the chain 12 can be pulled up to the ground and recovered.

Since the inclinometer 15 is attached to the structural steel frame ]O by the attraction force of the electromagnets 17, it is easily released from the steel frame 10 when the electromagnet [7] is demagnetized.

Therefore, it can be pulled up to the ground by the row 118 and recovered.

Example The illustrated invention will now be described in detail.

1 to 8 show flowcharts of the main steps of the structural pillar construction method of the present invention. First, Figures 1 and 2 show a pile hole 1 being excavated using a bending machine 3 using the reverse method, a stand vibrator 2 being pushed in, and the diameter being roughly expanded using a drilling machine 4.
3 shows the final step in which the diameter of the bottom of the hole is enlarged (bottom enlargement) III. Pile hole 1 is usually underground with a vertical accuracy of about 1/200.
It is carved to a depth of about 3m. In Figure 3, a hole wall measuring device 5 is installed on the upper end of the stand vibrator 2, a sensor cable 6 is lowered from the device to the center of the pile hole 1, and a hole wall sensor 7 attached to the tip of the cable 6 is used to measure the hole wall. Measure the pile hole 1.
It shows the stage of investigating wall surface trends.

Next, FIG. 4 shows a stage in which a pedestal 8 is installed at the upper end of the stand vibe 2, and a correction jacking device 9 is suspended as close to the bottom end of the stand vibe 2 as possible. The details of the configuration of this correction jacking device 9 are shown in FIGS. 9 and 10, and the stand vibrator 2 has an inner diameter of about 1.8 m or 2 m, while the outer diameter is about 1.6 m or 1.8 m. The ring 9a has a letter-shaped cross section, and four hydraulic jacks 9b are arranged in the radial direction in four directions at right angles to each other. Each hydraulic jack 9b is a bracket (9c) fixed to the inside of the ring 9a.
The support bottle 9d is passed through a long groove 9f provided near the base end of the jack holder 9e, and is attached in a freely undulating configuration. Therefore, the hydraulic jack 9b normally lies down (hangs down) as shown by the two-dot chain line in FIG. 9 due to its own weight. For this reason, if one end of the rope 111 is fixed near the free end of the hydraulic jack 9b and the other end of the rope 11 is secured on the ground, when the rope 111 is pulled as necessary, the hydraulic jack 9b will be placed in a horizontal position. can be made to stand up. When each hydraulic jack 9b in a horizontal position is driven,
The piston rod 9g extends and comes into contact with the inner surface of the stand vibe 2 to take up a reaction force, and moves the structural pillar steel frame 0 on the center side to correct the position. One end of the chain 12 is fixed to the ring 9a at 4wI positions equally dividing the circumference as shown in FIG. It is suspended into a predetermined position inside. Therefore, the correction jacking device 9 can be pulled up to the ground again by the chain 12 and recovered.

Next, Figure 5 shows a 1° structural steel frame with a length of about 26 m, with a pile hole of 1.
Fig. 6 shows the stage in which the upper end of the erected structural column steel frame 10 is aligned and fixed to the center of the pile hole 1 by the frame 8 and supported. The structural pillar steel frame 1o will be erected by vertically lifting it using a crane, etc. using Yatco 26 and Traverser 26 (Figure 5).
The structural column steel frame 10 has a shear connector 28 protruding from its tip as a factory process, or a gusset plate for joining the steel beams is attached. An inclinometer 15 is attached at a position near the lower end of the structural column steel frame 10, and in particular at a position slightly above the top of the concrete 160 poured at the bottom of the hole as shown in FIG. If necessary, one wire 20 (sixth
After fixing the wire 20 (see Figure), construction is carried out, and the other end of the wire 20 is secured on the ground. As shown in FIGS. 11 and 12 in detail, the inclinometer 15 is attached to a structural pillar steel frame 10 whose planar shape is square (or circular, H-shaped, etc.).
As shown in Figure 11, there are two
a is attached. ! On the top of the known inclinometer 16, which has a long cylindrical shape, there are two block-shaped electromagnets 17.17 with two arms 19.19 protruding from each side, one on each side. Installed in a symmetrical arrangement. Furthermore, a block-shaped electromagnet 17 with one arm 19 protruding from the bottom is attached. Therefore, by pressing the inclinometer 15 to a predetermined position on the structural column steel frame 10 in a predetermined manner and energizing each electromagnet 17 with a changeover switch, the inclinometer 15 can be immediately positioned and fixed (attached). One end of a row 118 is properly attached to the upper part of the inclinometer 15, and the other end of the row 118 and the electric cable 24 are secured on the ground when the main column steel frame 1o is erected. The electric cable 24 is connected to a ground recording and display meter (not shown).

The structural details of the frame 8 that supports the upper part of the structural column steel frame 10 built into the pile hole 1 are as shown in FIGS. 13 and 14. Two support beams 30 and 30 are prepared on the frame 8, and just before completing the erection of the main column steel frame 1θ, the verticality of the steel frame 1° is confirmed using the traverser 2G. Then, directly below the angle 31 of the Yatco 25 is the support beam 30.3.
After moving the frame 8 and fixing it with bolts, fix the angle 31.31 with the jack 32.32 that was previously installed on the support beam 30, and move the structural column steel frame 1O to the column center position. Support. By operating the jack 32, the height position of the structural column steel frame 1o 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 positional deviation or inclination of the structural column steel frame 1o measured by the two lower inclinometers 15° 15 becomes zero. and perform correction work.

After that, a mass 33 is installed on top of the tremie pipe 21 which is installed in advance of the structural column steel frame 10, and concrete is poured at the bottom of the hole (Fig. 7). During the construction period and until the concrete 16 hardens after pouring, the positional deviation and inclination of the steel frame 10 of the Company Corrections are made by controlling the jacking device 9 or by pulling wires 20 from the ground in various directions if necessary. Concrete 16 is placed at a depth of approximately 5 to 6 m at the bottom of the hole, and the concrete 16 is placed at the bottom of the hole to a depth of approximately 5 to 6 m. Bury the lower end of the IO to a sufficient depth. Therefore, concrete 16
Once the curing is complete, the column base will be firmly fixed.

After curing the concrete 16, first loosen and remove the hydraulic jack 9b of the correction jack device 9, and then remove the chain 1.
2 to raise it to the ground and collect it.

Next, the electromagnet 17 of the inclinometer 15 is demagnetized, and the row 118
Raise it to the ground and collect it.

Finally, a hopper 40 is attached to the upper end of the stand vibrator 2, and gravel 41 is thrown in to backfill the pile hole l (Fig. 8), completing the structure pillar.

As described in detail in conjunction with the examples above and beyond the effects of the present invention, the method for constructing a structural column according to the present invention is as follows: After the construction of a structural column steel frame 1O, concrete 16 Since the construction accuracy can be measured in real time with the inclinometer 15 and corrections can be made using the correction jack device 9 or the wire 20, extremely high construction accuracy of approximately 1/1000 can be achieved on the ground. Construction is carried out with perfect understanding. Therefore, it is possible to easily implement the reverse construction method using a column-beam frame of a steel frame that has been processed in a factory.

Moreover, the correction jacking device 9 and the inclinometer 15, which are auxiliary equipment for construction, can be completely recovered and reused, which is highly economical.

Furthermore, the construction method of the present invention can shorten the construction period because the erection of the main column steel frame 10, the pouring of concrete at the bottom of the hole, and the confirmation and correction of the erection accuracy are carried out in parallel in real time. It contributes.

[Brief explanation of the drawing]

Figures 1 to 8 are important process diagrams of the structural pillar construction method according to the present invention, Figures 9 and 10 are a partially enlarged cross-sectional view and a plan view showing the state in which the correction jacking device is used; Figures 11 and 12 are a plan view and a front view showing how the inclinometer is attached to the structural column steel frame, and Figures 13 and 14 are a plan view and a cross-sectional view of the pedestal. ... Stand vibe 1 ... Pile hole 8 ... Frame 9a ... Ring 9 ... Correction jacking device 15 ... Inclinometer 10 ... Structure pillar steel frame
16...Concrete 9b...Hydraulic jack 12...Chain 11...Rope 17...Electromagnet 20...Wire Fig. 10 Fig. 1 Fig. Fig. Fig. 11 Fig. 2 Fig.

Claims (1)

[Scope of Claims] [1] After excavating a pile hole using a stand pipe, a pedestal is installed at the upper end of the stand pipe, and a ring is mainly installed at a position as close to the lower end of the stand pipe as possible. The step of preparing for lifting the jack device is to erect a structural pillar steel frame with an inclinometer attached near the lower end into the pile hole, and the upper end of the structural pillar steel frame is supported by the mount at the center of the pile hole. , correcting the position and inclination of the structural column steel frame using the correction jack device so that the inclination of the structural column steel frame measured by the inclinometer becomes zero; and correcting the erection position of the structural column steel frame. After positioning, concrete is placed at the bottom of the hole, and changes in the position of the main column steel frame during and after concrete pouring are checked with an inclinometer, and the position and inclination of the main column steel frame are checked using a correction jack device. A construction method for structural pillars characterized by the following steps: After making corrections, concrete curing is performed and the column bases are fixed. [2] The modified jacking device has a structure in which the required number of jacks are oriented in the radial direction on a ring whose diameter is sufficiently larger than the external dimension of the structural column steel frame and smaller than the internal diameter of the stand pipe, and can be raised and lowered freely. Using the chain fixed to the ring, this modified jack device was suspended to a predetermined position inside the stand pipe, and with each jack lying down, the structural column steel frame was erected inside the ring. After that, each jack was erected in a substantially horizontal position by pulling the rope attached to each jack in advance, the position and inclination of the structural column steel frame was corrected, and after curing the concrete at the bottom of the hole, the corrective jack device was installed using a chain. A method for constructing a structure pillar as set forth in claim 1, characterized in that the structure pillar is recovered on the ground. [3] The inclinometer is installed using multiple electromagnets at a position near the bottom end of the main column steel frame, higher than the top of the concrete poured at the bottom of the hole, and at a right angle to the main column steel frame when viewed from above. At least two inclinometers are installed in the same direction, and each inclinometer is connected to a record display meter on the ground to measure and display the inclination of the structural column steel frame in real time. After curing the concrete at the bottom of the hole, the electromagnet is demagnetized and the inclination meter is The method for constructing a structural column as claimed in claim 1, characterized in that the inclinometer is recovered to the ground using a rope fixed to the gage. [4] A plurality of wires are fixed, one at a time, at multiple locations at the lower end of the main column steel frame, which are equally distributed in the radial direction when looking at the main column steel frame in the plane direction. The structural column steel frame according to claim 1, wherein the end thereof is secured on the ground, and the position and inclination of the structural column steel frame measured by an inclinometer are corrected by pulling the wire. Construction method.