JP2000186323A - Concrete pile with base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve earthquake resistance by combining a steel coil spring and a bellows-like steel pipe in a prescribed state. SOLUTION: A small coil spring 5 fixing the upper end on a washer 4 is inserted in a bellows-like steel pipe 1 providing a plurality of swellings 2 having a plurality of holes 3 and the washer 4 is fixed on the upper end of the steel pipe 1. Next, the lower end of a large coil spring 7 is fixed on the lower washer cylinder 14 of a lower washer 6, the steel pipe 1 is inserted in the spring 7, and the upper end of the spring 7 is fixed on the washer 4. Next, the washer 4 is fixed on the pile ring 9 of an upper pile 8, and the lower washer 6 is fixed on the pile ring 9 of a lower panel 15. Furthermore, the whole spring 7 is cylindrically covered by a steel plate, and the upper and lower ends are fixed on the washers 4, 6. During earthquake, the swelling 2 is crushed, and the springs 5, 7 are expanded and contracted to mitigate vertical fluctuation. Thereby earthquake resistance can be semipermanently secured to prevent the cracking and breakage of a pile, and structure can be made simple and firm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete pile (pile), which is an underground foundation, provided with a seismic isolation device. Conventionally, pile manufacturers and public organizations have repeatedly studied to install seismic isolation devices in piles, but they have not been able to solve them up to the present.

[0002]

2. Description of the Related Art A concrete pile (pile) is used as an underground foundation, and is buried in the ground by a casting method or a digging method. There was none. As a result, the Great Hanshin Earthquake caused many buildings to collapse, causing significant damage to bridges and other parts of the country.

[0003]

At present, no seismic isolation device is provided together with ready-made piles and cast-in-place piles. At present, there is no other way but to inject, and this method is also poor in reliability and its function as seismic isolation is far from far. Therefore, there was no other way but to build a pile with a diameter larger than necessary as a deep foundation, add more hardener than necessary, and provide psychological relief. The present invention has been made to eliminate these disadvantages.

[0004]

The present invention is an application of the characteristics of a steel coil spring and the characteristics of a bellows.
Hereinafter, the structure and function of the present invention will be described in detail. A round steel pipe (1) is provided with a plurality of bulges (2). (5 in FIG. 1) On the outer peripheral surface of each bulge (2),
An elliptical hole (3) is provided at a location where the outer circumference is divided into eight equal parts.
(In FIG. 1, three bulges per (2).)
The function of the elliptical hole (3) is that when a strong force is applied from above and below the steel pipe (1), cracks first enter around the elliptical hole (3). ) Collapses and the length of the steel pipe (1) is compressed to about 1/3, as if the bellows were in close contact. It is said that the Great Hanshin Earthquake, which was an inland-type earthquake just below the center, was a force that was applied vertically from the epicenter. The concrete pile, which is an existing pile, is manufactured by utilizing high-speed rotation and centrifugal force, but is hollow. Due to transportation problems, the maximum length is about 15 m, and any length less than this can be freely manufactured. Long and deep piles are added together. The pile has a pointed tip, but one is a steel ring ring and both ends are ring rings. The elasticity (spring constant) of the coil spring is determined by the material diameter, the average coil diameter, the number of turns, and the material (transverse elastic coefficient). The compression steel coil springs (5), (7), and (16) have the property of compressing when a force is applied, and returning to the original shape when the applied force is lost. The present invention utilizes this characteristic. A lower washer cylinder (14) is provided at the center of the lower washer (6), and one of the large coil springs (7) is fixed to the lower washer (6). A deformed steel pipe (1) containing a small coil spring (5) is inserted into the hollow of (7), the end of the deformed steel pipe (1) is fitted into the lower washer (14), and one large coil spring (7) is inserted. ) Is fixed to the washer (4). Since the steel pipe (1), the small coil spring (5) and the large coil spring have the same length, the three structures are integrated. Washer (4) and lower washer (6)
When a force is applied from both sides or one side is fixed and one side is applied, the large coil spring (7) starts to be compressed by the elasticity of the spring, and when further force is applied, the bulge (2) of the deformed steel pipe (1) A crack is generated from the elliptical hole (3), and eventually the bulge (2) is crushed, and the entire bulge (2) is compressed when the bellows is in close contact. During this process, deformed steel pipe (1)
Is also compressed at the same time.
When the compression force is lost, the large coil spring (7) and the small coil spring (5) return to their original shape. In the posture restored to the original shape, the tip of the small coil spring (5) is in the lower washer cylinder (14),
The large coil spring (7) also returns to its original shape before compression. The deformed steel pipe (1), which has just been compressed and becomes like a bellows, is in close contact with the washer (4) and does not hinder the subsequent movement of the coil spring. The same applies when the elliptical hole (3) is formed upright on the outer peripheral surface. Next, when the warp occurs again, both the large coil spring (7) and the small coil spring (5) are compressed. When the warp force is lost, both the large coil spring (7) and the small coil spring (5) are restored to their original shapes. . This expansion / contraction movement is used to reduce the sway. The concrete pile is buried in the ground by a hammer or a digging method or the like, and the driving with a hammer has a considerable impact force, but the driving force can be freely adjusted. A seismic isolation device consisting of a large coil spring (7) and a deformed steel pipe (1) is installed and integrated between a pile (8) and a lower pile (15). A pile ring ring (9) and a washer (4) may be fixed, and the pile ring ring (9) and the lower washer (6) may be fixed and connected.
Driving with a hammer has a considerable impact force, it is impossible to penetrate into the ground unless the deformed steel pipe (1) is provided, and the large coil spring (7) is damaged and broken, and above all, the lower panel (15) The driving force does not propagate throughout. Further, if the deformed steel pipe (1) is not provided, when the pile is lifted, the pile will bend and bend with the spring as a fulcrum, causing problems in storage and transportation. When the steel pipe (1) is not a deformed steel pipe (1) having a bulge (2) but a straight steel pipe, when a force is applied, the large coil spring (7) and the small coil spring (5) start compressing at the same time. However, a compression force is simultaneously applied to the straight steel pipe. When further force is applied, the straight steel pipe bends in a hollow shape inside the large coil spring (7), and the large coil spring (7)
Is damaged or broken, and at the same time, naturally, the small coil spring (5) built in the straight steel pipe is also damaged, and the original function of the compressed steel coil spring is lost. Therefore, deformed steel pipe (1)
Is the key to the mechanism and function of the present invention. The seismic isolation device composed of the deformed steel pipe (1) and the large coil spring (7) is mainly used to alleviate the sway of the earthquake. Apply. The details will be described below. The tension spring (12) has a characteristic of flexibly bending in all directions of 360 degrees and restoring to a straight original shape. At the center of the lower washer (13) of the tension spring, a small tension spring (16) longer than the post steel tube (11) is fixed, and this is inserted into the post steel tube (11) having a diameter larger than the diameter of the hole (17). Then, the end of the small tension spring (16) is projected out of the column steel pipe (11). The tip of this protruding small tension spring (16) fits inside the round steel cylinder (18). Next, in the hollow of the tension spring (12), a small tension spring (16) is built in the washer (13) under the tension spring, and the upright supporting steel pipe (11) is built up.
And fix the end of the tension spring (12) to the tension spring lower washer (13). Next, since the support steel pipe (11) and the tension spring (12) have the same length, a small tension spring (1) is used.
The tip of 6) protrudes from the tension spring (12), passes through the round hole (17) provided in the tension spring washer (10), and fits in the fixed round steel cylinder (18). Next, the tension spring (12) is fixed to the tension spring washer (10) to be integrated. The most important thing about this structure is the steel column (1
1) is not fixed to the tension spring washer (10) and the tension spring lower washer (13). This support steel pipe (1
When both ends of 1) are fixed to the upper and lower portions, the tension spring (1)
The characteristic of 2) may be reduced by half or may become impossible. This is because, in the case of swaying, the tension spring (12) bends in characteristics, but the function is reduced by half when the column steel pipe (11) is fixed, and the small tension spring (16) built in the column steel pipe (11) is also reduced. Function cannot be exhibited. The greatest function of the column steel pipe (11) is to effectively propagate the casting to the entire lower panel (15). Therefore, in the case of the sway of an earthquake, the sway is relieved by the characteristics of the tension spring (12), and the underground pile is prevented from cracking or breaking. The tension spring (12) for the purpose of alleviating and preventing the sway is different from the seismic isolation device composed of the deformed steel pipe (1) and the large coil spring (7), and is slightly different in the method of driving into the ground. . Less than,
This will be described in detail. Deformed steel pipe (1) and large coil spring (7)
The seismic isolation device consisting of the following was installed on the lower washer (6).
Since the end of the deformed steel pipe (1) is fitted in the lower washer cylinder (14), the pile (8) and the lower pile (15) are connected and integrated. Because of this, casting, storage,
There are no transportation problems. Since the seismic isolation device composed of the tension spring (12) does not fix the supporting steel pipe (11) anywhere, the tension spring (12) has weak strength even in the horizontal direction, and it is difficult to integrate it into the pile. is there. Thus, hammering halves the pile. First, the lower pile (15) is first set and penetrated, and the pile ring ring (9)
Piles (8) beforehand when they reach the ground surface
The seismic isolation device of the tension spring (12) is connected to the pile ring (9). It can be done in a short time if performed by electric welding. This is lifted, connected to and fixed to the pile ring ring (9) of the lower pile (15) previously driven, and the driving is restarted. The driving force is reliably transmitted to the lower pile (15) by the support steel pipe (11) in the hollow of the tension spring (12). By dividing the pile into two, storage and transportation problems are solved. Round steel cylinder (18) provided on tension spring washer (10)
Has no disadvantage because it enters the hollow of the pile (8). A method of providing the present invention in a digging method that does not rely on hammering or the like will be described. The inside digging method is a method in which an earth auger drill is inserted into the hollow of a concrete pile and the pile is weighed while drilling, and the pile is laid while being pressed. Since it is impossible to provide a deformed steel pipe (1) and a column steel pipe (11) in this method, these are excluded. Tension spring (1
In the case of 2), if the tension spring washer (10) and the tension spring lower washer (13) are ring ring washers except for the support steel pipe (11), the entire pile becomes entirely hollow, and an earth auger drill is inserted into this hollow. There is no inconvenience to enter. After the pile is settled, the pile head may be processed to provide a seismic isolation device including the large coil spring (7) and the deformed steel pipe (1). By this method, the quake and the quake can be reduced and prevented. The Great Kanto Earthquake is a plate-shaped earthquake peculiar to the coastal area, and it is said that the swaying was remarkably remarkable. The present invention is a concrete pile with a seismic isolation device having the above configuration and function.

[0005]

According to the present invention, the characteristics of the steel coil spring and the characteristics of the bellows are applied. In the case of an earthquake, the deformed steel pipe (1) is crushed and the bellows is in close contact. In the case of the sway, the sway is relieved by the characteristic of the tension spring (12), and the underground pile is prevented from being cracked or broken. It is generally said that the shallower the epicenter and the larger the earthquake, the greater the amplitude of the surface waves. Large coil spring (7) and small coil spring (5) and extension spring (12)
Is semi-permanently elastic, so that it is possible to remarkably relieve sway and sway. A stainless steel coil spring, which is said to be less likely to corrode, further extends its service life. The coating of the outer peripheral surfaces of the coil springs (7) and (12) with a steel plate is to protect the spring together with problems in storage and transportation of the pile, and to facilitate penetration into the ground. The coating (sheet steel) after penetration into the ground has no disadvantages to the function of the spring. This is because when the spring is compressed, the coated (thin steel plate) is also compressed, and the spring (outside the outer periphery)
The large coil spring (7)
Never get inside the hollow. Even if it enters the hollow, it is (thin steel plate), so (thick deformed steel pipe (1))
Unlike, it does not significantly affect the mechanism and function of the spring. The same applies to the case where the tension spring (12) is coated (a thin steel plate).

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A seismic isolation device comprising a large coil spring (7) and a deformed steel pipe (1), and a tension spring (12) and a support steel pipe (11) is provided in a pile. It is advisable to provide several places in the pile. It is said that the longer the pile becomes, the more the cracks and breakage occur due to the swaying movement, and there is a serious concern about cracks and breakage of the piles underground due to past earthquakes throughout the country, including the Great Hanshin Earthquake. Have been. The present invention is not only effective for hollow concrete piles, but also applicable to steel piles, cast-in-place piles, foundations of buildings, steel columns, joints between piers and bridges, etc.
In addition, it can be applied to utility poles that are always inclined and collapsed during an earthquake or typhoon. By providing a plurality of the present invention on a large-diameter pile such as a caisson according to the diameter, it is possible to remarkably reduce vertical and horizontal sway.

[0007]

The present invention is an application of the characteristics of a steel coil spring and the characteristics of a bellows. The structure is extremely simple and strong, and the mitigation of earthquake sway and sway is remarkably semi-permanently sustained. The effect of preventing pile cracking and breakage in the ground is especially great, and the effect in seaside landfills and soft lands is outstanding. It can be widely applied not only underground but also on ground structures.

[Brief description of the drawings]

 FIG. 1 is a perspective view of a part of the present invention. FIG. 2 is a perspective view of a part of the present invention. FIG. 3 is a cutaway perspective view of a main part of the present invention. FIG. 4 is a perspective view of a part of the present invention. FIG. 5 is a plan view of a part of the present invention. FIG. 6 is a plan view of a main part of the present invention.

[Explanation of symbols]

1 is a steel pipe 11 is a support steel pipe 2 is a bulge 12 is a tension spring 3 is an elliptical hole 13 is a tension spring lower washer 4 is a washer 14 is a lower washer cylinder 5 is a small coil spring 15 is a lower panel 6 is a lower washer 16 is a small tension spring 7 is a large coil spring 17 is a hole 8 is a pile 18 is a cylinder 9 is a pile ring ring 10 is a tension spring washer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2D041 AA01 AA02 BA00 CB06 DB02 DB03 2D046 DA12 DA43 3J048 BC03 BC09 EA38

Claims (2)

[Claims] 1. A steel pipe (1) is provided with a plurality of bulges (2) to form a deformed steel pipe, each bulge (2) is provided with a plurality of holes (3), and a washer (4) is provided. The small coil spring (5) is fixed, inserted into the hollow of the steel pipe (1), and the washer (4) is fixed to the end of the steel pipe (1). (B) The lower washer (6) is provided with the lower washer cylinder (14), one of the large coil springs (7) is fixed to the lower washer (6), and the small coil spring (5) is placed in the hollow of the large coil spring (7). The built-in steel pipe (1) is inserted, the end of the steel pipe (1) is inserted into the lower washer cylinder (14), and one of the large coil springs (7) is fixed to the washer (4). (C) Fix the washer (4) to the pile ring ring (9) of the pile (8), and attach the lower washer (6) to the lower panel (15).
The pile (8) and the lower pile (15) are connected and fixed. (D) The entire large coil spring (7) is covered with a steel plate in a cylindrical shape,
The cylindrical end is fixed to the washer (4) and the lower washer (6). Concrete pile with seismic isolation device configured as above. 2. A small tension spring (16), which is longer than the support steel pipe (11), is fixed to the center of the tension spring lower washer (13), and has a diameter larger than the diameter of the hole (17). The small tension spring (16) is inserted into the support steel pipe (11), and the end of the small tension spring (16) projects out of the support steel pipe (11). (B) An upright support steel pipe (11) is placed in the hollow of the tension spring (12), and the end of the tension spring (12) is fixed to the tension spring lower washer (13). (C) A small tension spring (1) protruding outside the support steel pipe (11)
Insert the end of (6) into the hole (1) provided in the tension spring washer (10).
7) fit into the round steel cylinder (18) fixed on the upper part,
The tension spring (12) is fixed to the tension spring washer (10). (D) The tension spring washer (10) is fixed to the pile ring ring (9) of the pile (8), and the tension spring lower washer (13) is fixed to the pile ring ring (9) of the lower pile (15). (8) and the lower pile (15) are connected and fixed. (E) The entire tension spring (12) is covered with a steel plate in a cylindrical shape, and the cylindrical end is fixed to the tension spring lower washer (13) and the tension spring washer (10). The concrete pile with a seismic isolation device according to claim 1 configured as described above.