JPH0321684B2 - - Google Patents

Description

[Detailed description of the invention] In this invention, after constructing every other preceding pile,
The present invention relates to a construction method and apparatus for constructing and connecting post-driven piles between the preceding piles and constructing a water-stop wall using a row of these piles.

As shown in Figure 1, this type of construction method is as follows:
When installing post-driven piles 2 between the preceding piles 1 that have been constructed at intervals of every other pile, cement paste is injected at high pressure from the post-driven pile side toward the side of the preceding piles 1 to form a water-stop film between the piles d. There were many construction methods that formed 3.

In this construction method, if the vertical accuracy of the leading pile 1 and the trailing pile 2 or the construction accuracy of the pile core is poor, the distance d between the piles will become larger than the set value, and the cement paste by injection will reach the side of the trailing pile 2. Complete water-stop film 3
You may not be able to obtain it.

Also, depending on ground conditions, it may be possible to cut the gap between the leading pile 1 and the cement paste.
As shown in FIG. 2, there were cases in which the cement paste spread along the side surfaces of the preceding piles 1, and the water-stopping film 3 was not formed across the piles.

Furthermore, even if the ground is cut with injection cement paste, as shown in Figure 3, there are many problems with water-stopping properties, such as the water-stopping film 3 being thin and sometimes breaking, and it is still not sufficient. It was hard to say.

This invention was developed to eliminate the drawbacks of the conventional construction methods mentioned above and to always obtain a reliable water-stopping effect, regardless of pile construction accuracy or ground conditions.

The present invention achieves the water-stopping property of the row of piles without relying on the water-stopping film formed between the piles.
The pile array is integrated by direct connection between the piles and interlocking of the connected portions, thereby improving water-stopping properties.

The above-mentioned direct connection of the piles to each other is achieved by placing other piles between the low-strength piles that have been previously driven in pairs at intervals of every other pile, and by wrapping the other piles around the preceding piles and driving them later.
Furthermore, the engagement of the joint portion is achieved by mechanically cutting the opposing side surface of the preceding pile in the vertical direction during construction of the post-driving pile, and filling the groove created therewith with a portion of the post-driving pile.

In the pile row water stop wall constructed as described above,
Watertightness is further improved by the mutual connection of the piles by laps and the interlocking inside the piles, and because the grooves for the interlocking are mechanically cut, the cutting grooves are the same and highly accurate in all previous piles. occurs, and each pile is tightly and evenly integrated, providing a water-stopping effect that cannot be obtained with the conventional construction method.

The construction of the preceding piles and post-driving piles and the mutual connection of the piles can be easily and reliably performed by using a construction device consisting of two augers.

This construction device consists of a pair of augers that have flights connected around the shaft and are equipped with cutting blades on both sides of the head that can be freely expanded, and are mounted on a drive device at a required interval. The blade is expanded during construction of a driven pile, and when the auger is pulled up, the blade is used to vertically cut the side surface of an adjacent pile to form a groove in the pile.

This invention will be explained in detail below with reference to embodiments shown in FIG. 4 and below.

Reference numeral 11 denotes a construction device, which consists of a double auger in which a pair of augers 12, 12 each having a flight around its axis are provided in parallel to a drive device 13. Each of the above augers 1
Blades 14, 14 are provided on both sides of the heads 2, 12 so as to be freely expandable. Also, the augers 12, 12 can drive a pair of leading piles,
They are provided on the drive shaft device 13 at a distance that allows construction of a post-driven pile that overlaps with the preceding pile.

First, a pile hole is excavated using the construction device 11, and the pile hole is filled with low-mix mortar while the device is pulled up from the auger head.
Pairs are poured in advance at intervals of every other.

Next, the ground between the leading piles 15, 15 is excavated using the same construction device 11. In this case, the flights of the augers 12, 12 are the leading piles 15, 1.
5 and excavate the sides of the preceding piles 15, 15 in a circular manner together with the ground.

When the excavation is completed, both augers are stopped and the augers 12, 12 are reoriented so that the blades 14, 14 are centered on the sides of the adjacent piles.
The blades 14, 1 are then
4 and press fit the tip of the blade into the adjacent pile.

After the above preparation, the mortar that was pumped into the shaft while gradually pulling up the construction device 11 is filled into the gap created by the pulling up with the auger head, and the pile 1
Perform pouring of 6.16. At this time, the blade 1
4 and 14 are leading piles 15 and 1 cut into an arc shape.
As shown in FIG. 9, the center of the opposing sides of the pile 5 is further cut to form directional grooves 17, 17 in the pile.
The depth of the cutting grooves 17, 17 is the same as that of the blades 14, 1.
4, and can be changed arbitrarily.

The grooves mechanically cut as described above are filled with a portion of the mortar squeezed out from the auger head as the augers 12, 12 move upward.
Post-cast piles 16 and 16 and preceding piles 15, 15
The two overlap with each other and are watertightly connected and integrated by the cut grooves 17, 17 and the engagement with the portions 16a, 16a of the post-drilled piles filled therein.

After driving the post-driven piles 16, 16, the construction device 11 is moved to another place, and an insert member 18 such as an H-beam is immediately pushed into the post-driven piles. The above-mentioned steps are then repeated to complete the row of pile waterstop walls 19 having inserts 18 for every other pile.

9 and 10 show the tip of the auger 12, where 20 is a shaft and 21 is a head member jointed to the lower end of the shaft. A flight 22 is provided around the shaft 20 and the head member 21, and a digging blade 23 is attached to the tip of the head member 21.

Inside the shaft 20 and the head member 21, although not shown, there is an opening 24 on the side surface of the tip of the head member 21.
A mortar pumping path is provided. A flow path 25 for high pressure injection is provided in the shaft, and a cylinder 26 connected to this flow path 25 connects to the head member 21.
It's decorated.

This cylinder 26 is for expanding the pair of blades 14, 14, which are suspended by a support shaft 28 from bearings 27 protruding from both sides of the lower part of the head member 21, and are constantly held upward by a spring member 29. It has a compressed piston 30. Further, below the cylinder 26, there is a pair of plungers 3 which are in contact with the lower surface of the blade 14 and expand the blade 14 upward.
1 and 31 are inserted into the casings 32 and 32 to face each other, and a communication hole 33 is provided between the plungers 31 and 31 and the cylinder 26.

The flights 22 around the shaft include a pair of nozzle members 3 that communicate with a flow path 25 for high-pressure injection within the shaft.
4 and 34 are charged horizontally, and the fluid pumped into the flow path 25 pressurizes the piston 30, while
The air is ejected from the edge of the flight via the nozzle members 34, 34.

The high pressure jet through the nozzle members 34, 34 is used when cutting the leading piles 15, 15. That is, the preceding pile 15 cut by the flight 22,
15 is primarily cut by spraying a coagulating material such as cement paste at high pressure from a nozzle in contact with the side surface, and then further cut by blades 14, 14 to form the cut groove 17 of a predetermined size. 17
Used when forming.

As described above, this invention involves constructing post-drilled piles between the preceding piles so that they overlap each other, and furthermore, a vertical cut groove is formed in the side surface opposite to the preceding pile in the lapped portion, and the cut groove Since the pile and a part of the post-drilled pile are integrated in an interlocking state, reliable water-stopping performance can be obtained even if the pile construction accuracy is slightly reduced.
Moreover, since the grooves are cut mechanically, they are not affected by ground conditions and can be formed according to the set dimensions.
Since the cutting groove is filled for each pillar, water leakage from the water stop wall can be completely prevented when root cutting is completed.

Furthermore, as for the construction device itself, it is only necessary to construct a pair of augers with expandable blades on both sides of the auger head, separated by the required distance, and because both flights are separated,
Even if the rotational speeds of both augers do not perfectly match the flight intervals, as is the case when the flights are lapped, there is no risk of intersecting flights or difficulty in discharging the excavated soil. Furthermore, the geared motor that is the driving source can be arranged in two series, and there is no need to synchronize each other, making it easy to operate when constructing a pile row waterstop wall.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional plan view explaining the conventional pile row water-stopping wall construction method, Figures 2 and 3 are cross-sectional plan views showing the drawbacks of the conventional construction method, and Figures 4 and below are the pile row water-stopping method according to the present invention. This figure shows an example of the wall construction method and device. Figure 4 is a schematic front view of the construction equipment, Figures 5 to 7 are cross-sectional plan views explaining the construction process, and Figure 8 is a water cutoff wall. FIG. 9 is a front view of the auger tip, and FIG. 10 is a longitudinal front view thereof. 11...Construction device, 12...Ogre, 13...
Drive device, 14... Blade, 15... Leading pile,
16... Post-driving pile, 17... Cutting groove.

Claims (1)

[Scope of Claims] 1. Low-strength piles are driven in pairs at intervals of every other pile, the piles are wrapped between the preceding piles, and the piles are later driven, and a water-stop wall is constructed using these rows of piles. In construction, when constructing the post-driven pile, a vertical groove is cut in the opposite side of the preceding pile using mechanical means, and a part of the post-driven pile is filled into the cut groove. A construction method for a pile row waterstop wall characterized by connecting both piles in a watertight manner. 2. A pair of augers with flights connected around the shaft and expandable blades on both sides of the head that cut opposite sides of adjacent piles to form vertical grooves in the piles. The driving device is equipped with two drive devices with an interval that enables the driving of a pair of leading piles, and the construction of a trailing pile that overlaps with the leading pile.
A construction device for pile row waterstop walls consisting of a row of augers.