JPH0573853B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an on-site mortar pile construction method, and in particular improves the ground by compacting the excavated soil around the pile hole without discharging it. , relates to an on-site mortar pile construction method in which mortar piles are formed inside the pile holes, and a pile driver used for the method.

(Prior Art) When constructing a building, it has been common practice to drive piles into the lower part of the foundation to improve the supporting strength of the ground. For this purpose, concrete piles are used and driven with a pile driver, but recently, driving prefabricated piles with a pile driver is no longer used due to the noise it generates. is decreasing.

Instead, there are methods of drilling pile holes in the ground with an earth drill etc. and driving existing piles into the holes, or mixing solidifying agents such as cement milk into the excavated soil, thereby forming piles. It is common practice to form

For example, the construction method mentioned above is
There are some such as those shown in Publication No. 56-14808.
The construction method shown in this conventional example uses an earth auger to excavate a pile hole in the ground, and after forming a hole of a predetermined depth, mixes the solidifying material while rotating the auger in the opposite direction, and then mixes the solidified material into the excavated soil. This system hardens the soil through the reaction between the solidified material and the solidified material, and also consolidates the ground, making it possible to improve the ground.

In addition to the above-mentioned conventional examples, there is also a method of mixing excavated soil with a liquid solidification material, but all of these methods use excavated soil as the main material and solidify the soil. They are often made to form so-called soil piles.

(Problems to be solved by the invention) However, when constructing cast-in-place piles,
If the nature of the ground is such that it reacts well with cement, the hardening agent will react well with the excavated soil, but if the soil at the site is highly acidic or has organic matter If a large amount of cement is mixed, the hardening material may not harden due to the reaction with the alkali of the cement, and a pile may not be formed.

In addition, depending on the nature of the ground, reaction time with cement may be longer and it may take more time to form piles, resulting in unfavorable conditions such as a longer foundation construction period. may occur.

In addition, with conventional construction methods, it is not possible to form all of the soil in the excavated pile holes into piles, so some of the excavated soil is discharged. . Since the excavated soil is often mixed with a hardening material, it cannot be treated in the same way as ordinary soil, and cannot be treated by spreading it around it.

Therefore, if there is no space to dump soil near a construction site, it is necessary to transport the soil to a distant dumpsite for disposal, which requires a lot of time and effort to dispose of the remaining soil. Therefore, other drawbacks such as increased construction costs often occur.

It is also possible to use a conventional pile driver to pull up the screw without rotating it, but in such a configuration, even when building a pile with a diameter of about 30 cm, the pulling force will not be enough. 30〜
It is necessary to set it to 40t.

For this purpose, it is necessary to use a crane truck with a large capacity, which increases the size of the entire device, making it difficult to handle small-scale construction work.

(Objective of the Invention) The present invention solves the drawbacks of conventional construction methods as described above. The purpose is to provide a construction method that allows piles to be formed using mortar without ejecting soil to the ground, and to provide a small excavation device.

(Means and effects for solving the problem) The in-situ mortar pile construction method of the present invention is such that the screw is pressed into the ground by rotating the screw, and then the screw is pulled out without rotating, and the pile is excavated. Consolidating the earth and sand around the hole, and driving a lifting device for pulling up the screw and a mortar pump for pumping the mortar by the same hydraulic device,
This construction method is characterized in that a mortar pile is created by force-feeding mortar to the lower part of the screw and pulling up the screw using a pulling device in parallel.

In addition, the device used for the on-site mortar pile construction method of the present invention includes a pile driver that has a screw provided at the bottom of the hollow rod and is driven by a hydraulic motor, and a pile driver that is integrally attached to a predetermined part of the hollow rod. A lifting device configured to engage with and pull up the provided collar, and a mortar pump for pumping mortar are provided, and these devices are connected to hydraulic pressure supplied by the same hydraulic device. It is configured to be driven by.

Therefore, when pulling up a screw that has been press-fitted to a predetermined depth, the cylinder of the lifting device and the mortar pump are driven simultaneously, and the lower part of the screw is pulled up while balancing the forces of both members. The screw is filled with mortar to push up the screw, and the mortar pile can be constructed in good condition.

Furthermore, according to the construction method of the present invention, the excavated soil is left in a compacted state around the pile hole, so it is not discharged to the ground, and there is no need to spend time disposing of the remaining soil. .

In addition, since the pile driver of the present invention can be constructed in a small size, it can be easily applied to small-scale construction work, improves maneuverability, and reduces noise. Since the occurrence of such problems can be prevented, construction work can be easily carried out in densely populated residential areas.

(Example) The structure of the pile driver of the present invention will be explained according to the illustrated example.

As shown in FIG. 1, the apparatus of the present invention includes a pile driver 1 comprising a hydraulic motor 2 for press-fitting a screw 5 into the ground, a pulling device 10,
Hydraulic device 20 and mortar pressure pump 25
It consists of The hydraulic motor 2 of the pile driver 1, the cylinder 11 of the lifting device 10, and the hydraulic motor 26 of the mortar pump 25 are driven using the hydraulic pressure generated by the hydraulic system 20. .

The pile driver 1 of the present invention is comprised of a hollow rod 3 driven by a hydraulic motor 2 and a screw 5 provided at the tip of the hollow rod 3. Further, an opening is provided in the lower part of the hollow rod 3, and a joint 28 is formed in the upper part of the opening.

The screw 5 is formed to become gradually thinner toward the top, and a tapered portion 6 is formed, and digging teeth are formed at the bottom thereof in the same manner as conventionally used screws. Furthermore, collars 4, 4a, 4b... are fixed at predetermined intervals in the middle of the hollow rod 3 of the present invention, and the collars 4 are pulled up when lifting the screw 5, as will be described later. The locking member 15 of the device 10 is adapted to be engaged.

The lifting device 10 of the present invention includes a plurality of vertically provided cylinders 11 and the cylinders 1
1, an upper member 13 to which the cylinder rod is locked, and an upper member 1.
3 and the locking member 15.

Further, a lower iron plate 17 with a hole 17a corresponding to the diameter of the hole is placed above the hole 31 to be excavated, and the pile hole 31 is excavated through the hole, and the screw 5 is pulled. When raising, the upper iron plate 16 divided into two parts is placed on top of the lower iron plate 17.

When the two upper iron plates 16 are put together, a hole 16a is formed in the center of the upper iron plate 16, which is large enough to allow the collar 4 of the hollow rod 3 to pass through.
The soil lifted by the screw 5 is pressed by the upper iron plate 16 and the lower iron plate 17 so as not to be discharged to the ground.

The mortar pressure pump 25 for press-fitting the mortar into the mortar pile hole 31 through the hollow rod 3 is a mortar pump that has been commonly used in the past.
A hydraulic motor 26 is used as its driving source.

Then, mortar is poured from the mixer truck 36 into the hopper provided on the mortar pressure pump 25, and
The mortar 35 is sent out from the hopper via the mortar pressure feeding hose 27, supplied to the hollow rod 3 from the joint 28, and sent out through the hollow hole of the hollow rod 3 toward the opening provided at the bottom of the screw 5, The mortar is discharged into the pile hole 31 from the opening.

The hydraulic system 20 of the present invention includes a hydraulic pump 2
1, an oil tank 22, and piping 24 connecting the hydraulic valve 23 and each device,
Pipes 24a and 24b are connected to the cylinder 11, and piping 24 is connected to the hydraulic motor 26.
c and 24d are connected. Further, since the driving time of the hydraulic motor 2 of the pile driver 1 is different, a separate system of piping is provided.

Then, the pile hole 31 is excavated using the pile driver of the present invention, and after the pile hole 31 has been excavated to a predetermined depth, the pulling device 10 and the mortar pressure pump 25 are driven, and the mortar is pumped. The work of pulling up the screw 5 is performed simultaneously and in parallel.

Next, a case where on-site mortar piles are created using the pile driver of the present invention will be described.

As shown in FIG. 2A, the hydraulic motor 2
The pile hole 31 is excavated by the screw 5 by driving and pushing down with a predetermined pressure. At that time, the lower iron plate 17 is placed at the excavation position of the ground 30, and the screw 5 is press-fitted through the hole 17a. After the screw 5 is inserted, the upper iron plate 16 is placed, and the hole in the center is inserted into the hollow rod 3.
It is set so that it holds. In this state, a pile hole 31 is excavated to a predetermined depth, and the excavated soil 32 is left above the screw 5.

After the pile hole 31 is drilled to the planned depth,
Filling with mortar and pulling up the screw 5 are performed. In this case, the hydraulic valve 23 shown in FIG. 1 is operated to send hydraulic pressure from the hydraulic pump 21 to the cylinder 11 and the mortar pump 25 via the pipes 24a and 24c.

Therefore, the hydraulic pressure sent from the hydraulic pump 21 drives the cylinder 11 and the mortar pump 25 at the same time, and as shown in FIG. The mortar will be discharged at the same time.

In this case, the high pressure mortar sent out from the mortar pressure pump 25 passes through the hollow part of the hollow rod 3 from the mortar pressure feed hose 27,
It is discharged from the lower end of the hollow rod 3 under the screw 5 and fills the space, and the pressure causes the screw 5 to rise. 5 will be applied at the same time.

Therefore, the screw 5 is gradually raised, but the excavated soil 32 above the screw 5 is pressed by the upper iron plate 16 and the lower iron plate 17 at the above ground part, so that the pile hole 31 is Instead of being discharged upwards, it is pressed to the side of the hole by the tapered portion 6 of the screw 5, and the ground around the hole 31 is consolidated.

Then, as shown in FIG. While the consolidation work is carried out, a mortar filling section 33 is formed at the bottom of the screw, and the construction of the on-site mortar pile is completed.

When the screw 5 is pulled up, the upper and lower iron plates 16 and 17 installed on the ground are pressed by the legs 12 of the cylinder 11, and as the screw rises, soil is pushed into the pile hole 31.
The excavated soil 32 is consolidated around the pile hole 31 and strengthens the ground. And Screw 5
By setting the feeding pressure of the mortar feeding pump 25 to a high level, the mortar filled in the lower part of the pile hole 31 will be filled without any gaps, and the pile will be formed with high strength. become.

Note that it is possible to create a mortar pile by filling mortar to a depth corresponding to the length of the last remaining screw part after removing the upper and lower iron plates 16 and 17, but normally Since the area is excavated and the foundation concrete is placed, it is not necessary to place mortar on top of the pile hole.

In addition, in the on-site mortar pile construction method of the present invention, when pulling up the screw 5, the locking member 15 of the pulling device 10 is sequentially moved to the collar 4b,
4a, 4... and is pulled up by the cylinder 11, so that the cylinder 1
The stroke of color 1 and the interval of color 4 are preferably set to be the same.

In the above-mentioned pulling device of the present invention, if the locking member 15 is configured as a device that can change the size of the engaging portion with the hollow rod 3 using hydraulic pressure, the effort required to pull up the screw 5 can be reduced. Furthermore, it is also possible to easily configure the pulling device 10 to have an arbitrary shape as needed.

(Effects of the Invention) Since the on-site mortar pile construction method of the present invention performs the operations described above, the on-site mortar pile can be constructed by a hydraulic drive device.
During this work, it is possible to suppress the generation of vibration and noise as much as possible.

In addition, in the on-site mortar pile construction method of the present invention, the excavated soil is not discharged to the ground, so there is no need to dispose of the remaining soil. Since the surrounding area can be consolidated and the ground can be strengthened, the frictional force of the mortar piles built in the pile holes becomes extremely large, making it possible to increase the supporting strength of the building.

Furthermore, the pile driver of the present invention enables construction without the use of large equipment, so it can be easily applied to construction work in narrow spaces, and the screw has a large pulling force. It is possible to excavate a pile hole and create a mortar pile using the same hydraulic power source without using other equipment such as a crane, etc., and the strength of the created pile is uniform. , it becomes possible to easily design the supporting parts of the building, and it is possible to reliably eliminate the possibility of uneven settlement, etc. occurring after the construction of the building.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the configuration of the pile driver of the present invention, and Figure 2 is an explanatory diagram showing the construction state of the present invention.
-C are explanatory diagrams showing the construction order of mortar piles, respectively. Symbols in the diagram: 1... Pile driver, 2... Hydraulic motor, 3... Hollow rod, 4... Collar, 5... Screw, 6... Taper part, 10... Pulling device, 11... Cylinder. , 12...leg, 13...
... Upper member, 14 ... Link, 15 ... Locking member,
16...Upper iron plate, 17...Lower iron plate, 20...Hydraulic system, 21...Hydraulic pump, 22...Oil tank,
23... Hydraulic valve, 24... Piping, 25... Mortar pressure pump, 26... Hydraulic motor, 27...
...Mortar pressure feed hose, 28...Joint, 3
0... Ground, 31... Pile hole, 32... Excavated soil, 33... Mortar filling part, 35... Mortar.

Claims (1)

[Claims] 1. The screw is pressed into the ground by rotating the screw, and then the screw is pulled up without rotating to compact the excavated earth and sand around the hole, and the screw The lifting device for lifting the screw and the mortar pump for pumping the mortar are driven by the same hydraulic device, and the feeding of the mortar to the lower part of the screw and the lifting of the screw by the lifting device are performed in parallel. A method for constructing mortar piles on site, characterized in that mortar piles are constructed in a similar manner. 2 A screw is provided at the bottom of the hollow rod, and the pile driver is configured to be driven by a hydraulic motor, and the screw is engaged with a collar provided integrally at a predetermined portion of the hollow rod to cause the screw to be pulled up. An on-site mortar pile characterized in that it is provided with a lifting device consisting of the above-mentioned structure and a mortar pressure pump for force-feeding mortar, and is configured to be driven by hydraulic pressure supplied by the same hydraulic device. Pile driver for construction method. 3. A patent claim characterized in that the screw is configured in a tapered shape that gradually becomes thinner upward, and by pulling up the screw, the excavated soil in the upper part is pressed toward the periphery of the hole. A pile driver according to item 2 of the scope of the invention.