JP3058135U - Continuous underground wall construction equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a construction device for a continuous underground wall, which has both a high construction speed and a high construction accuracy, and enables the excavated excavated soil to be discarded or used for another purpose. An apparatus for constructing a continuous underground wall using a multi-axis auger includes a plurality of auger shafts each having substantially continuous spiral blades of the same pitch and one auger having discontinuous stirring blades. A step of forming a communicating drilling hole by using an excavating shaft portion composed of a shaft and being driven at the same speed in the same direction in a state where the spiral wings overlap each other by an arbitrary amount; And replacing the mortar with a mortar.

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention relates to a continuous underground wall construction apparatus using a multi-axial auger, and in particular, a required amount of excavated soil at a construction site and a hardened material are mixed on the ground, and the amount of excavated soil required for the construction of an underground wall is used. And the hardening material are mixed and used as a construction wall material, so that the mixed soil as industrial waste is compared with the conventional construction method in which the excavated soil and the hardening material are kneaded and stirred during excavation work in the ground. The present invention relates to a continuous underground wall construction apparatus with reduced construction cost and high construction efficiency.

[0002]

[Prior art]

 The prior art will be described with reference to FIGS. FIG. 3 shows the structure of a general pile driver. A three-point support crawler pile driver 10 supports a mast 12 by a back stay of a crawler crane 11 and is supported by a leader pipe 13 of the mast 12. A single auger shaft 15 is driven via a speed reducer 14 that moves up and down. The auger shaft 15 of such an apparatus is provided with a spiral wing 16 which is an auger flight over the entire length thereof, and an auger head 17 at the tip thereof has a mortar jet port and a pre-pump in addition to a drill bit. Mortar outlets (both not shown) are generally provided. In FIG. 3, reference numeral 18 denotes an insertion reinforcing cage, and GL denotes a construction ground surface.

FIG. 4 is a schematic explanatory view of a so-called PIP pile method of a conventionally well-known type. As shown in FIG. 3A, a driving device is attached to the head of a single hollow auger shaft 15 having a normal continuous flight 16 as shown in FIG. 3, for example, and the entire device is suspended from a tower. (Not shown), and excavates and inserts underground to a predetermined depth. Next, as shown in FIG. 3B, while the auger is being lifted, mortar corresponding to the amount of the auger is pressed into the hollow hole of the auger shaft to replace the excavated earth and sand with the mortar. At this time, all the excavated earth and sand is removed by the continuous flight 16 provided on the auger shaft.

FIG. 1C shows a state in which the excavated soil drilled by the auger and the mortar separately prepared are completely replaced to form a cast-in-place pile of the complete mortar 19. In this case, the mortar to be press-fitted may be, for example, a mixture of separately prepared aggregate and cement milk, or a mixture of a part of the excavated earth removed by an auger and a hardened material. Subsequently, as shown in FIG. 3D, a PIP pile is formed by inserting a reinforcing bar 18 or a shape steel at a stage where the mortar 19 is not yet cured, and one such PIP pile is formed. The column-type underground wall can be constructed by casting continuously and can be used as earth retaining or water blocking wall for civil engineering structures.

On the other hand, the apparatus shown in FIG. 5 is an apparatus used in a known construction method for efficiently forming an underground continuous wall, and uses a multi-axis auger having a large number of excavating shafts 15 as shown in FIG. In addition, earth and sand excavated in the ground and hardened material such as cement milk injected from the tip of the shaft of the auger are kneaded in the ground, and mortar striking a column row portion that is continuously continuous simultaneously by a number of auger shafts. Setting is completed.

That is, for example, a crawler pile driver 10 similar to that shown in FIG. 3 is a type in which three auger shafts 15 are driven via a speed reducer 14 provided on a mast 12 of a crawler crane 11. In addition to the excavation bit at the tip of each auger shaft 15, a hardened material jet (not shown) such as cement milk is provided at the shaft end, and each auger shaft 15 is provided with a stirring blade. The helical wings 30 are installed partially, ie discontinuously.

[0007] Using the multi-axis auger 10 of this type, for example, one axis at the end is guided through the existing guide hole, and at the same time, the ground of a new portion is excavated by the other two axes. At the same time, during the excavation process, excavation and agitation are performed while cement milk or the like is spouted from the spout at the shaft tip. In this way, the excavated soil and the hardened material are kneaded and hardened in the excavation hole, whereby the underground wall is continuously and efficiently driven.

[0008]

[Problems to be solved by the invention]

 The above-mentioned known methods have the following disadvantages. As shown in Figs. 3 and 4, a pile driver with one auger shaft having spiral wings over its entire length was used, and as mortar, aggregate or excavated earth and cement milk etc. were separately used. The hardened material is prepared in advance, and the excavated soil is all discharged to the ground by spiral wings while mortar is spouted from the tip of the auger shaft.

[0009] Therefore, there is an advantage that the excess excavated soil can be discarded as general earth and sand. However, the construction efficiency is low when using the conventional method, and when the next pile is continuously driven next to the existing unhardened mortar pile, the pile hole already drilled is There was a drawback that both the construction speed and construction accuracy caused problems, such as the inclination of the next excavation axis being affected.

Further, in the construction method using the apparatus as shown in FIG. 5, although the construction speed and construction accuracy are certainly improved, excavated soil and hardened material such as cement milk are kept underground. Since it is agitated and kneaded by the spiral blades provided discontinuously on the auger shaft, the excess mixed soil discharged must be disposed of as so-called industrial waste.

However, in today's social situation, it is extremely difficult to dispose of industrial waste, and the cost for that purpose accounts for a large proportion of the construction cost. The present invention is intended to solve such various problems by providing a continuous underground wall construction apparatus which has a high construction speed and construction accuracy, and enables the excavated earth to be discarded or used for another purpose. It is.

[0012]

[Means for Solving the Problems]

 The first aspect of the present invention is a multi-shaft auger excavating shaft structure, in which a plurality of shafts are rotatably driven in the same direction at the same speed, and one end shaft is rotatable in the opposite direction. Auger shafts, each of which can be connected to the reduction gear section of a shaft drive device, each having substantially continuous spiral blades of the same pitch, and one auger shaft having discontinuous stirring blades A mortar can be ejected from the tip of each auger shaft, and the outer peripheral ends of the spiral wings of the plurality of auger shafts overlap each other in plan view. Structure. Secondly, the inter-axle distance between the auger shafts in the excavation shaft portion is set to be smaller than the diameter of the spiral blade and larger than the sum of the radius of the spiral blade and the radius of the auger shaft. It is assumed that. Thirdly, the discontinuous stirring blades at the auger shaft at one end of the excavation shaft portion are characterized in that they have dimensions that do not interfere with each other by being made significantly smaller than the diameter of the other continuous spiral blades. .

[0013]

[Embodiment of the invention]

 One embodiment of the present invention will be described with reference to FIGS. The auger support means, the drive mechanism, and the like in the apparatus of the present invention are the same as those of a conventionally known multi-axis auger as shown in FIG. 5, for example, and the description of the common members will be omitted. However, although the description of the specific structure of the drive mechanism in the present invention is omitted, the auger shafts having a plurality of spiral blades can be driven at the same speed in synchronization with each other, and the other one end can be driven. The auger shaft is required to have a structure that can be driven to rotate synchronously or asynchronously with the plurality of auger shafts in the opposite direction.

FIGS. 1 and 2 schematically show, for example, portions corresponding to three auger shafts 15 in the known multi-axis auger shown in FIG. 5 (hereinafter, referred to as excavation shafts). It is shown in Accordingly, each of the illustrated auger shafts 25A and 25B has a drill bit at the tip 27 and a mortar outlet at the shaft end. However, these structures are particularly novel. Therefore, detailed description is omitted. In addition, for example, in the vicinity of the tips of the three auger shafts 15, a known inter-axis connecting means is mounted between the spiral blade of each shaft and the tip of a drill bit or the like so that each of the shafts can be moved. Is preferably constrained to any selected interval.

FIG. 1 shows a plane (A) and a front (B) according to an embodiment of a digging shaft portion 20 having a plurality of auger shafts 25A and 25B unique to the present invention. The arrangement of the auger shafts 25A and 25B and the shapes of the spiral blade 26 and the stirring blade 30 are shown. That is, as in the illustrated embodiment, an auger shaft 25B at one end of, for example, three auger shafts constituting the excavating shaft portion 20 is provided with a stirring and kneading blade comprising a number of discontinuous spiral blades. Alternatively, it has a simple stirring blade (hereinafter, referred to as a stirring blade) 30.

Of course, the structure of the stirring blade 30 itself can be the same as the structure of the stirring blade 30 in the known multi-axis auger shown in FIG. 5, but the shape is not particularly limited. Absent. The diameter of the stirring blade 30 is smaller than that of the other spiral blades 26, so that the stirring blade 30 does not always interfere with the adjacent spiral blade 26. It is also possible to make the blade diameter of the stirring blade 30 equal to the blade diameter of the spiral blade 26, but in this case, the rotation direction of the shaft 25A having the spiral blade 26 and the rotation of the shaft 25B are changed. By opposing and synchronizing, it is necessary to prevent wing tip interference with each other.

Similarly, the other two auger shafts 25A constituting the excavation shaft portion 20 are provided with a plurality of auger shafts connected vertically from a tip end thereof to a substantially upper end thereof. It has a substantially continuous spiral wing 26 over its entire length. Further, as is apparent from the plane (A) of the figure, in this embodiment, the two auger shafts 25A having the continuous spiral blades 26 are synchronously rotated in the clockwise direction shown by arrows. The auger shaft 25B having the stirring blade 30 at one end is driven to rotate in the counterclockwise arrow direction.

Furthermore, the pitches of the continuous spiral blades 26 provided on the two auger shafts 25A are equal, and the rotational phases of the two spiral blades are substantially the same as shown in FIG. One wing end of the spiral wing 26 of two adjacent auger shafts 25A is located between the other upper and lower wing ends, so that the shafts are rotated synchronously in the same direction. Accordingly, the spiral blades and the stirring blades of each of the auger shafts 25A and 25B are arranged such that the auger shafts are brought close to each other as shown in the figure, and the trajectory of each blade 26 ends in the plane (A). Also, each wing can rotate freely without interference, and excavation work is possible.

FIG. 2 shows an excavation shaft portion 20 composed of two auger shafts 25 A having spiral blades 26 similar to those shown in FIG. 1 and one auger shaft 25 B having similar stirring blades 30. And an embodiment of a structure in which the auger shafts are closer to each other. That is, as is apparent from the state of the plane (A) in FIG. 2, for example, since the ends of the two spiral wings 26 are rotated in the same direction while overlapping each other, these two auger shafts are used. The excavation hole excavated by 25A is in a completely connected state, and as will be described later, the cast mortar wall is reliably formed continuously. Therefore, in the case of an underground wall having more complete water blocking properties, a method of rotating and driving the spiral wings 26 sufficiently overlapping each other is advantageous.

Next, a process of forming a continuous underground wall according to the present invention will be described. The excavating shaft portion 20 shown in FIG. 1 or FIG. 2 is set on a reduction gear 14 of a known multi-shaft auger 10, for example, as shown in FIG. Then, in a separate plant or the like, the mortar is adjusted by kneading, for example, earth and sand produced by excavation at the construction site and cement milk, and an arbitrary casting position is excavated by the multiaxial auger 10.

In the above-described step corresponding to FIG. 4A, for example, when the means shown in FIG. 1 is used for the excavation shaft portion 20, the excavation holes formed by the respective auger shafts correspond to the plane of the spiral blade 26 in FIG. The same drilling hole row as in the state (A) is formed, and each drilling hole becomes a drilling hole row communicating with the adjacent part. Similarly, when the means shown in FIG. 2 is used, the drilling holes formed by the respective auger shafts overlap each other at a considerable portion, and therefore, similarly to the plane (A) state of the spiral wing 26 shown in FIG. It is clear that the rows of drill holes are completely connected.

In the following, a description will be given of a case where the excavation operation is performed repeatedly using the excavation shaft portion 20 continuously from the state shown in FIG. 1 or FIG. 2 in the left direction on the paper. In the process, the auger shaft 25B having the agitating blade 30 at one side end is inserted into, for example, one leading drilling hole or a drilling hole at the foremost part where mortar has already been cast one stage before the drilling hole. In addition to serving as a guide for the excavating shaft portion in the excavating process, the auger shaft 25B is rotationally driven in a direction opposite to that of the other auger shafts 25A so as to balance excavation reaction force by the auger as much as possible. ing.

As a result of these construction steps, the excavated earth and sand discharged to the ground by the spiral wings 26 of the auger shafts 25A is, of course, as it is on-site, and contains no hardening material or the like. Not something. Therefore, part of the sediment discharged at this stage can be used as aggregate for the next casting mortar, if necessary, and the remaining sediment can be used for other purposes like ordinary sediment. It is possible to dispose of it as mere earth for civil works.

Contrary to the above case, it is also possible to repeatedly excavate the excavation shaft portion 20 from the state of FIG. 1 or FIG. 2 toward the right side of the drawing of FIG. In this case, one auger shaft 25A at the left end of the figure is inserted into the leading drilling hole or a drilling hole drilled by the auger shaft 25B one stage before the same, and the same operation as above is repeated. In this case, since the auger shaft 25B at one lateral end plays a role of digging a leading hole for the next digging step, it is not necessary to always blow out mortar from the auger shaft 25B.

Next, the mortar cast into the excavation hole by the multiple auger shafts 25A and the single auger shaft 25B forms at least mutually continuous walls, and the steps up to this point are sequentially repeated. In this way, it is possible to construct a continuous ground stop water wall, but in general, a reinforcing process using a reinforcing member such as a steel cage or a section steel is performed. Then, by sequentially repeating the above steps, it is possible to construct a continuous underground wall or earth retaining wall having a high water-stopping property with high accuracy and high workability.

In this way, the distance between the auger shafts 25A and 25B in the excavating shaft portion 20 that can be mounted on a conventionally known continuous underground wall forming machine is set arbitrarily, and a number of auger shafts 25A are set. By arbitrarily setting the degree of overlap of the outer diameter ends of the spiral wings 26 in the above, the thickness of the communicating portion between the columns in the continuous underground wall can be set. Can also be constructed freely.

[0027]

[Effect of the invention]

 According to the structure of the excavation shaft part according to the present invention, a column wall for water stoppage having a communication part of an arbitrary thickness can be constructed with an extremely simple structure, and its strength and water stoppage performance are required as necessary. , Construction speed and the like can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view and a front view of an embodiment of an excavation shaft portion in a continuous underground wall construction device according to the present invention.

FIG. 2 is a plan view and a front view of another embodiment of the excavation shaft portion in the continuous underground wall construction device according to the present invention.

FIG. 3 is a schematic explanatory view showing a pile driving state using a conventionally known uniaxial auger.

FIG. 4 is an explanatory view of each driving step by the pile driving machine shown in FIG. 3;

FIG. 5 is a schematic view of a conventionally known multi-axis auger type underground wall construction apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Three-point support crawler pile driver 15, 25 Auger shaft 17, 27 Auger head 20 Excavation shaft part 26 Spiral blade 30 Stirrer blade

Claims (3)

[Utility model registration claims] 1. A multi-shaft auger excavating shaft structure, wherein the excavating shaft portion rotatably drives a plurality of shafts in the same direction at the same speed, and one end shaft is rotatable in the opposite direction. A plurality of auger shafts that can be connected to a reduction gear section of a certain shaft drive device, each having a plurality of substantially continuous spiral blades of the same pitch, and one auger shaft having discontinuous stirring blades A mortar can be ejected from the tip of each auger shaft, and the outer peripheral ends of the spiral blades of the plurality of auger shafts overlap each other in plan view. 2. An inter-axle distance of each auger shaft in the excavation shaft portion is set to be smaller than a diameter of the spiral blade and larger than a sum of a radius of the spiral blade and a radius of the auger shaft. The excavation shaft structure according to claim 1. 3. The diameter of the discontinuous stirring blade at one end of the auger shaft in the excavation shaft is substantially smaller than the diameter of the other continuous spiral blade and does not interfere with each other. The excavation shaft part structure according to claim 1 or 2,