JPH0438246B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a method of constructing a continuous underground wall, and particularly to a method of connecting and constructing a continuous underground wall along a predetermined virtual curved surface.

<<Prior Art>> As is well known, the locking pipe method is a type of construction method for continuous underground walls constructed underground.

In this construction method, after drilling a hole for the preceding panel to a predetermined depth, locking pipes are inserted at both ends of the hole, concrete is poured, and the concrete is removed before the concrete hardens. A panel is formed, and then a trailing panel is formed by drilling a trailing hole on the side of the leading panel and pouring concrete.Then, by repeating the same process, the panels are successively placed on the side. Form a connection.

According to this construction method, continuous underground walls can be constructed not only in straight lines but also in curved shapes along virtual curved surfaces, but in particular, when constructing curved walls,
I had a problem which is explained below.

≪Problems to be solved by the invention≫ In other words, for example, when constructing an earth retaining wall with a circular cross section using a continuous underground wall, the rocking pipe method
This can be achieved by forming the leading and trailing panels along the curvature of the circle and making them polygonal. However, as the curvature of the circle increases, the intersection angle of the leading and trailing panels becomes smaller, and the leading and trailing panels - There was a problem in that overlapping occurred between the trailing panels, making it difficult to excavate a borehole for the trailing panels.

Additionally, when excavating the overlapping area between the leading and trailing panels, the edge of the leading panel is likely to be missing.
This caused some outrage as the watertightness between the panels was compromised.

This invention was made in view of the above circumstances, and its purpose is to provide a method for easily constructing a curved continuous underground wall without impairing the watertightness between the panels. Our goal is to provide the following.

<Means for Solving the Problems> In order to achieve the above object, the present invention forms leading panels at predetermined intervals on a virtual curved surface, and then forms trailing panels between the leading panels. In the method for constructing a continuous underground wall along the virtual curved surface, an excavator having a cutting edge that expands from the inside to the outside of the virtual curved surface after excavating the excavation hole for the preceding panel. A substantially triangular-shaped excavation hole is excavated at the end of the excavation hole, and the preceding panel is formed by making the excavation hole for the preceding panel into a substantially trapezoidal shape with a hypotenuse substantially perpendicular to the virtual curved surface. do.

<<Operation>> According to the method for constructing a continuous underground wall with the above configuration, the excavation hole for the preceding panel is approximately trapezoidal, and the hypotenuse thereof is perpendicular to the virtual curved surface, so that the excavation hole for the following panel is shaped like a trapezoid. It is sufficient to excavate parallel to this oblique side.

<<Example>> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of the method for constructing a continuous underground wall according to the present invention.

The method for constructing a continuous underground wall shown in the figure is applied to the construction of an almost perfectly circular earth retaining wall, as shown in its entirety in Figure 1. It is composed of leading panels P1 to P7 and trailing panels S1 to S7.

In constructing the earth retaining wall 10, first, preceding panels P1 to P7 are formed on the virtual curved surface A at predetermined intervals.

In the forming process of each preceding panel P1 to P7, the first
As shown by the solid line in the figure, a rectangular excavation hole 12 having a rectangular cross section is excavated to a predetermined depth.

The rectangular excavated hole 12 is formed using, for example, a hydrophrase drilling device while filling it with muddy water.

When the rectangular excavation hole 12 is formed, at both ends thereof, as shown by the hatched portions in FIG. A substantially triangular excavation hole 14 is excavated and formed.

To excavate this triangular excavation hole 14, a drilling rig 16 shown in FIG. 2 is used.

The drilling equipment 16 shown in the figure has the rectangular drilling hole 1.
2, a pair of grab buckets 20, 20, and attachment blades 22, 22 fixed to the outer ends of the grab buckets 20, 20, respectively. ing.

The attachment blades 22, 22 have the same cross-sectional shape as the triangular excavation hole 14, and the drilling device 16 uses the hole wall surface of the rectangular excavation hole 12 as a guide, and sequentially drills triangular excavation holes on both end faces thereof. 14 to a predetermined depth.

When the above excavation process is completed, the preceding panel P1
~ The drill hole for P7 has a substantially trapezoidal shape with triangles joined at both ends of a rectangular cross section, and a reinforcing bar cage is then built inside this trapezoidal drill hole 24 to replace muddy water and concrete. Panels P1-P7 are constructed.

When the construction of the preceding panels P1 to P7 is completed, excavated holes for the following panels S1 to S7 are drilled between these preceding panels P1 to P7, respectively.

The excavation device used for this excavation is preferably a hydrophrase excavation device, which excavates to a predetermined depth while cutting and shaping both end faces of the preceding panels P1 to P7 in parallel by about 10 cm.

Then, after erecting reinforcing bar baskets into the excavated holes for the trailing panels S1 to S7, concrete is poured to construct the trailing panels S1 to S7, thereby completing the substantially circular earth retaining wall 10.

Now, in the method of constructing an underground continuous wall through the steps described above, the excavation holes for the preceding panels P1 to P7 are trapezoidal excavation holes 24 whose hypotenuses are almost perpendicular to the virtual curved surface A. Preliminary panel P1
The excavation holes for the trailing panels S1 to S7 to be excavated between -P7 can be excavated parallel to this oblique side, and the difficulty of excavation unlike the conventional method is eliminated.

Further, by cutting both end surfaces of the preceding panels P1 to P7 in parallel, the bonding between the preceding and following panels P and S becomes strong, and sufficient water-stopping properties can be ensured.

FIG. 3 shows the preceding panels P1 to P1 in the above-mentioned embodiment.
Another example of the excavation device for excavating and forming triangular excavation holes 14 at both ends of the rectangular excavation hole 12 for P7 is shown.

The example shown in this figure is a tipping type excavation device, in which excavation blades 28 with different protrusion amounts are successively arranged at intervals so as to form a triangular shape on both sides of the excavation device main body 26. It is inserted into the rectangular excavated hole 12 from above to form a triangular excavated hole 14.

In this case, the excavated earth and sand will be discharged using an air lift, bucket, etc.

Even if a drilling rig configured in this way is used,
The same effects as in the above embodiment can be obtained.

<<Effects of the Invention>> As described above in detail in the examples, according to the method for constructing a continuous underground wall according to the present invention, the water-tightness between the panels of a continuous underground wall with a curved surface is not impaired, An excellent effect can be obtained by easily constructing this structure.

[Brief explanation of drawings]

Fig. 1 is an overall plan view showing an example of a continuous underground wall constructed by the method of the present invention, Fig. 2 is an explanatory diagram of an apparatus for excavating a triangular excavation hole, and Fig. 3 is an apparatus for excavating a triangular excavation hole. It is an explanatory view showing other examples of. 10...Earth retaining wall, 12...Rectangular excavation hole, 14...
...Triangular drilling hole, 16...Drilling equipment, 24...
Trapezoidal drilling hole, P1-P7...preceding panel, S1
~S7... Trailing panel, A... Virtual curved surface.

Claims (1)

[Claims] 1. In a method for constructing a continuous underground wall along the virtual curved surface by forming preceding panels at predetermined intervals on a virtual curved surface and then forming trailing panels between the preceding panels, After drilling an excavation hole, a substantially triangular excavation hole is excavated at the end of the excavation hole using an excavator having a cutting edge that expands from the inside to the outside of the virtual curved surface, and the preceding panel A method for constructing a continuous underground wall, characterized in that the preceding panel is formed by forming an excavation hole into a substantially trapezoidal shape with a hypotenuse substantially perpendicular to the virtual curved surface.