JP2016065366A - Hydraulic setting solidification material liquid substitution column construction method and hydraulic setting solidification material liquid substitution column construction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic setting solidification material liquid column having the cross-sectional area and strength as plan design, even if a drilling hole diameter is occasionally reduced, by strengthening the ground of the drilling hole periphery, by pressurizing in the direction for expanding its drilling hole diameter, by expecting reduction in the drilling hole diameter formed by drilling the ground.SOLUTION: The ground is excavated up to the predetermined depth, while rotating a drilling rod 1a, by using a hydraulic setting solidification material liquid substitution column construction device for connecting a drilling head 2 having a discharge port 2b communicating with its flow passage 1d, to a lower end part of a drilling rod 1a having the flow passage 1d of a hydraulic setting solidification material liquid, and afterwards, when constructing a hydraulic setting solidification material liquid substitution column by filling a hydraulic setting solidification material liquid in a drilled hole, while rotating the drilling rod 1a or pulling up by nonrotation, rubbing projections 3a and 3b provided on the drilling rod 1a are rubbed against a drilling hole wall surface in the direction for expanding the drilling hole diameter.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hydraulic solidifying material liquid replacement column building method and a hydraulic solidifying material liquid replacement column building apparatus constructed by a basic construction method of a relatively small structure such as a small-scale building such as a detached house or a dirt slab. About.

  As a basic construction method for detached houses and soil slabs, a columnar improvement method (hereinafter referred to as a “column method”) by a deep mixed processing method is widely adopted. However, in the column method, the in-situ ground and cement slurry are agitated and mixed, so when cohesive soil with high adhesive strength is targeted, a co-rotation phenomenon occurs, resulting in poor quality due to poor mixing, organic soil, etc. Depending on the type of ground, there was a problem that solidification failure occurred. In addition, unexpected soil quality that could not be found in prior ground surveys may appear, and there is always a risk of poor quality.

  As a prior art for solving this problem, a construction method of a hydraulic solidifying material liquid replacement column and a construction apparatus (see Patent Document 1) of a hydraulic solidifying material liquid replacement column have been proposed. In the first place, the cause of poor quality such as poor mixing and solidification of soil cement that is built by stirring and mixing the ground and hydraulic solidification liquid is the mixing and mixing of the hydraulic solidification liquid and the original ground soil In view of the above, the prior art is to build a columnar body with only the hydraulic solidifying material liquid without stirring and mixing the ground soil and the hydraulic solidifying material liquid. Therefore, the built-in hydraulic solidification material liquid replacement column is high strength and high quality because the surrounding in situ soil is not mixed, and even if the surrounding in situ soil is organic soil, solidification failure does not occur, High strength and high quality can be demonstrated without being affected by soil quality.

  Further, as an improved technique related to the technique of Patent Document 1, a drilling head and a drilling apparatus (see Patent Document 2) for a drill rod for building a hydraulic solidifying material liquid replacement column have been proposed. This technique can greatly improve the excavation performance by using a conical excavation head (conical head) provided with a spiral blade on the peripheral surface. In addition, a single-claw type drilling head inevitably generates a lump of dirt that adheres to the claw when rotating, but a conical head can dramatically reduce the amount of sediment that adheres to it, and the drill rod can be pulled up. There is an advantage that earth and sand adhering to the conical head sometimes can be prevented from falling.

  As shown in FIG. 8, the construction procedure by the excavation head and the excavation apparatus of Patent Document 2 includes (a) a excavation head having a spiral excavation blade 33 and a hydraulic solidifying material liquid discharge port 34 on the peripheral surface. (Conical head) 32 is attached to a construction machine (not shown) with a hydraulic solidifying material liquid replacement column construction device 31 comprising a drilling rod 31a without a soil removal mechanism connected to the lower end, and the tip center portion of the drilling head 32 Is set to the pile center position. (B) The digging is performed while the excavating rod 31a is rotated forward. At this time, the discharge of the hydraulic solidifying material liquid from the discharge port 34 in the excavation head 32 is not essential. (C) When the predetermined excavation depth is shallower than the length of the excavation rod 31a, the excavation is stopped in a state where a part above the excavation rod 31a is on the ground. (D) When the predetermined excavation depth is deeper than the length of the excavation rod 31a, the excavation is performed until a part of the connecting rod 31b penetrates into the ground, and stops at the predetermined depth position. When the predetermined depth is deeper, the connecting rod 31b may be added. (E) Thereafter, the excavating rod 31a is pulled up in a normal rotation state while discharging the hydraulic solidified material liquid 35 from the discharge port 34 in the excavating head 32. At this time, the pulling speed of the excavating rod 31a and the discharge amount of the hydraulic solidifying material liquid 35 are adjusted so that no negative pressure is generated when the excavating rod 31a is pulled up. Although the rotation direction of the excavation rod 31a at this time may be reverse, the adhering earth and sand of the excavation head 32 is supported by the excavating blades 33, but the adhering earth and sand of the excavation head 32 is prevented from falling. In order to achieve this, forward rotation is preferred. (F) The excavating rod 31a is pulled up to the ground, the amount of the hydraulic solidifying material liquid 35 is adjusted, and the hydraulic solidifying material liquid 35 is filled to a predetermined depth position.

JP2011-106253A JP2013-234557A

  Such prior art hydraulic solidification liquid replacement columns are used for small-scale buildings such as detached houses and small-scale structures such as foundations for soil slabs. Depending on the situation, several are built close together. However, the construction of the hydraulic solidifying material liquid replacement column according to the prior art is to drill the hole by forcibly penetrating the ground sideways by forcibly penetrating the ground while rotating the excavating rod 31a. It is characterized by being built by filling with a hydraulic solidifying material solution. Therefore, when building a plurality of hydraulic solidifying material liquid replacement columns close to each other, another hydraulic solidification is performed at a position adjacent to the hydraulic solidifying material liquid replacement column in which the hydraulic solidifying liquid is not yet solidified in the hole. When the material liquid replacement column is constructed, the pressure (mainly the side pressure) transmitted through the ground along with the construction acts on the hole. For this reason, in addition to reducing the cross-sectional area of this drilling hole and the hydraulic solidifying material liquid replacement column that is not yet solidified in this drilling hole, the liquid level of the hydraulic solidifying material liquid increases with this reduction, Sometimes overflow from the surface.

  Also, from the construction principle of drilling by drilling rod 31a into the ground by forcibly displacing the ground sideways, the ground on the inner wall surface of the drilling hole will return elastically during construction, Due to the delayed elastic return phenomenon that occurs after drawing (after construction), the bore diameter may be reduced, which may reduce the cross-sectional area of the hydraulic solidifying material liquid replacement column that is not yet solidified in the borehole, As the bore diameter decreases, the level of the hydraulic solidifying material liquid rises, and depending on the soil, it sometimes overflows from the ground surface. Therefore, as a result, there is a problem that a hydraulic solidifying material liquid replacement column having a finished shape = diameter as planned may not be constructed.

  The present invention solves the above-mentioned conventional problems, and the object of the present invention is to rub the ground around the hole by strongly rubbing while expanding the inner peripheral wall surface of the hole in the diameter increasing direction. In order to increase the compaction ground strength and reduce the diameter of the drilling hole (thinning), there is virtually no problem. Pressurize the wall surface of the hole to expand the diameter while strengthening the ground around the hole, and install another hydraulic solidification liquid replacement column in the vicinity of the column to receive the side pressure associated with the work. Or a solidification liquid replacement column construction method and a water structure that make it possible to build a hydraulic solidification liquid replacement column that maintains the cross-sectional area and strength as planned, even if a delayed elastic return phenomenon of the ground occurs. Hard solidifying material liquid replacement column building equipment It is to provide.

In order to achieve the above object, the hydraulic solidifying material liquid replacement column building method according to claim 1 of the present invention is provided with a discharge port communicating with the flow path at the lower end portion of the excavating rod having the flow path of the hydraulic solidifying material liquid. Using a hydraulic solidification liquid replacement column construction device connected to a drilling head, excavating to a predetermined depth of the ground while rotating the excavation rod, and then discharging hydraulic solidification liquid from the discharge port of the excavation head It is a hydraulic solidification material liquid replacement column construction method for constructing a hydraulic solidification material liquid replacement column by pulling up a drilling rod with or without rotation and filling a drilling rod with a hydraulic solidification material liquid.
A rubbing projection is provided at a predetermined position on the side surface of the lower portion of the excavating rod over a predetermined length along the excavating rod. Is rubbed in the direction of expanding, and the ground around the inner peripheral wall surface of the drilling hole is compacted while expanding the drilling hole diameter.

  By this construction method, when digging in the ground by the rotation of the excavating rod, the rubbing projection protruding to the outer periphery of the excavating rod rubs the hole wall surface having an inner diameter corresponding to the excavating rod diameter in the direction of expanding the inner diameter. Press. By rubbing the hole wall surface, the soil around the hole wall surface is compacted so as to be closely bonded, the density is increased within a predetermined range, and the ground strength at this part is increased. Therefore, the hydraulic solidification material liquid is filled in the borehole expanded in this way, and when the hydraulic solidification material liquid is not yet solidified, another hydraulic solidification is performed on the surrounding ground near the drilling position. Even if the material liquid replacement column was constructed and a side pressure was received through the ground accompanying this construction, it was planned even if the bore diameter filled with hydraulic solidification material liquid was reduced or deformed. The built diameter can be secured. As a result, it is possible to reduce the excessive increase and overflow of the hydraulic solidifying material liquid accompanying the diameter reduction of the hole. In addition, after pulling out the drilling rod from the drilling hole, the outer diameter of the hydraulic solidifying material liquid replacement column filled is kept within the planned design length and outer diameter size even if elastic return occurs in the ground near the drilling hole. be able to. Such an effect can be quickly and smoothly filled with the hydraulic solidifying material liquid into the drilling hole by a simple operation of rubbing the rubbing projection against the hole wall surface during the drilling operation of the drilling rod.

In the hydraulic solidifying material liquid replacement column building method according to claim 2 of the present invention, the rubbing protrusion has a semicircular cross section.
With this configuration, it is possible to smoothly slidably contact the inner wall surface of the drilling hole without scraping the inner wall surface during drilling, and to improve the rubbing effect by reducing the rotational resistance. .

In the hydraulic solidifying material liquid replacement column building apparatus according to claim 3 of the present invention, a drilling head having a discharge port leading to the flow path is connected to a lower end portion of the drilling rod having a flow path of the hydraulic solidifying material liquid. A hydraulic solidifying material liquid replacement column building device,
A rubbing projection for rubbing the inner peripheral wall surface of the drilling hole in a predetermined direction on the side surface of the lower portion of the drilling rod in the direction of expanding the drilling diameter, and compacting the ground around the inner peripheral wall surface of the drilling hole while expanding the drilling diameter, It is provided over predetermined length along.

  With this construction device, when digging in the ground by the rotation of the excavating rod, the rubbing projection protruding to the outer periphery of the excavating rod rubs the hole wall surface having an inner diameter corresponding to the excavating rod diameter in the direction of expanding the inner diameter. Press. By this rubbing operation by pressing the wall surface of the drilling hole, the diameter of the drilling hole is expanded and compacted so that the soil around the ground surface of the drilling hole wall is closely bonded, and the density is increased within a predetermined thickness. The ground strength at the site is increased. Therefore, the hydraulic solidification material liquid is filled in the borehole expanded in this way, and when the hydraulic solidification material liquid is not yet solidified, another hydraulic solidification is performed on the surrounding ground near the drilling position. Even if the material liquid replacement column is constructed and a lateral pressure is applied through the ground in connection with this construction, the reduction or deformation of the bore diameter filled with the hydraulic solidifying material liquid can be suppressed. As a result, it is possible to reduce the excessive increase and overflow of the hydraulic solidifying material liquid accompanying the diameter reduction of the hole. In addition, even after the excavation rod is pulled out from the drilling hole, the outer diameter of the filled hydraulic solidifying material liquid replacement column is set to the length and outer diameter size in the planned design even if elastic return occurs in the ground near the drilling hole. Can fit. Such an effect can be realized by a simple and inexpensive configuration in which a rubbing protrusion is provided on the outer periphery of the excavating rod.

In the hydraulic solidifying material liquid replacement column building apparatus according to claim 4 of the present invention, the rubbing protrusion has a semicircular cross section.
With this configuration, the inner peripheral wall surface of the hole is not scraped off during construction, and the inner peripheral wall surface of the hole can be smoothly slid and the rotational resistance can be reduced.

  Further, in the hydraulic solidifying material liquid replacement column building apparatus according to claim 5 of the present invention, the excavation head is a conical head projecting in a conical shape downward, and the peripheral surface of the conical head is provided with this conical head. It has a vertical ridge along the circumferential surface or a spiral blade in a direction to push up the earth and sand excavated during the forward rotation of the excavation rod, and a discharge port for hydraulic solidifying material liquid leading to the passage of the excavation rod It is characterized by.

  The form of the excavation head is not particularly limited, and a conventionally known one can be used. However, with this configuration, the excavation soil is pushed upward when the vertical protrusion or the excavation rod rotates along the circumferential surface of the conical head. If the spiral wing of the direction is fixed, the excavation in the ground is good, and the formation of soil blocks at the excavation part does not occur physically. In particular, in the case of a spiral wing in the direction of pushing up the excavated earth and sand at the time of normal rotation of the excavating rod, since it has a function to support the earth and sand adhering to the spiral wing part, it prevents the adhering earth and sand from falling, It is more preferable because there is no fear of mixing of excavated soil blocks due to construction in the hydraulic solidifying material liquid replacement column.

According to the present invention, when the ground is excavated by the rotation of the excavating rod, by applying the rubbing projection to the hole wall surface in the direction of expanding the hole diameter, the hydraulic solidifying material liquid of the column is not solidified again. In addition, when another hydraulic solidifying liquid replacement column is constructed at a nearby position, even if the side pressure transmitted through the ground acts on the drilling hole, or if the drilling hole shrinks due to the delayed elastic return of the ground, it is rubbed. Since the ground around the drilling wall is firmly compacted by the rubbing operation by the protrusions, it is possible to suppress the reduction of the inner diameter of the drilling hole of the column, and to replace the hydraulic solidification material liquid that ensures the cross-sectional area and strength of the planned design Columns can be built.

  In the present invention, the hydraulic solidifying material liquid is a self-hardening powder and water such as Portland cement that is hydrated and solidified with water as main components, for example, cement slurry (cement milk), A mortar containing fine aggregate made of sand, etc., and a fluid that is made of (cement) concrete that also contains coarse aggregate such as gravel or crushed stone with a small diameter that can be discharged from a discharge port, and that can be pumped. .

  The present invention has been briefly described above. The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

It is a perspective view of the principal part which shows the hydraulic solidification material liquid replacement column construction apparatus by embodiment of this invention. It is a cross-sectional view of the hydraulic solidifying material liquid replacement column construction apparatus main part shown in FIG. It is a front view which shows the modification of the hydraulic solidification material liquid replacement column construction apparatus shown in FIG. It is a perspective view of the principal part which shows the hydraulic solidification material liquid substitution column construction apparatus by other embodiment of this invention. It is a cross-sectional view of the main part of the hydraulic solidifying material liquid replacement column building apparatus shown in FIG. It is a perspective view of the principal part which shows the modification of the hydraulic solidification material liquid replacement column construction apparatus shown in FIG. It is a principal part perspective view which shows another embodiment of a digging head. It is explanatory drawing which shows the construction procedure of the conventional hydraulic solidification material liquid substitution column.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view of a main part of a hydraulic solidifying material liquid replacement column building apparatus showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the main part in FIG.

  This hydraulic solidifying material liquid replacement column building apparatus 1 includes a drilling rod 1a having a conical head 2 connected as a drilling head at the lower end. In the present embodiment, the conical head 2 has a conical shape whose diameter decreases downward, and a spiral blade (spiral excavation blade) 2a is fixed on the peripheral surface thereof, and does not overlap with the spiral blade 2a. A hydraulic solidifying material liquid discharge port 2b is provided at the position. A backflow prevention valve 2c for preventing backflow of earth and sand is attached to the discharge port 2b. Further, the discharge port 2b communicates with the inner pipe 1d which is a flow path of the hydraulic solidifying material liquid.

  A pair of rubbing protrusions 3a and 3b having a crescent-shaped cross section are integrally provided on the side surface of the lower portion of the excavation rod 1a along the excavation rod 1a over a predetermined length h. The pair of rubbing protrusions 3a and 3b are provided so as to have an elliptical shape or an oval shape when viewed from the top, and have a high effect of rubbing while expanding in the radial direction of the inner peripheral wall surface of the drilling hole. This is preferable because resistance is reduced. The rubbing protrusions 3a and 3b rub at least the inner peripheral wall surface of the drilling hole in the direction of expanding the drilling diameter when the excavating rod 1a is digging, and compact the ground around the inner peripheral wall surface of the drilling hole while expanding the drilling hole diameter. Therefore, having a certain length h along the excavating rod 1a is preferable because it can be rubbed and compacted over a wide range of hole lengths, and can be reliably rubbed and compacted. If the length is too long, rotation resistance, digging resistance and pulling resistance increase, which is disadvantageous in that a large construction machine is required. The length h is taken into consideration. The length h of the rubbing protrusions 3a and 3b can be exemplified as a preferable length that is about 1 to 2 times the diameter D of the excavation rod 1a.

  In addition, the diameter of the drilling hole (thinning thinning) is less likely to occur over the entire length of the drilling hole, and the position generated by the ground properties, the depth of the drilling hole, the spacing between adjacent replacement columns, etc. changes. It is not constant. Therefore, the position of the excavation rod 1a where the rubbing protrusions 3a and 3b are provided only needs to be provided at a position that can cover the range in which the diameter of the drilling hole is reduced. However, since it is difficult to specify the range in which the diameter is reduced for each drilling hole, the lower part of the drilling rod 1a is rubbed over almost the entire length except for the part near the hole bottom of the drilling hole. This is preferable because it can be hardened and the ground near the inner peripheral wall surface of the hole can be strengthened. These rubbing protrusions 3a and 3b are made of a metal equivalent to the excavation rod 1a and the conical head 2, for example, a steel material. The rubbing projections 3a and 3b are firmly attached to the excavation rod 1a by using fastening members such as bolts and nuts or welding. The rubbing protrusions 3a and 3b have the same shape and size, and have a cross-sectional shape with the largest thickness at the center of the crescent moon and the smallest thickness at the end. These end portions may have a thickness that substantially matches the outer diameter of the outer periphery of the excavation rod 1a. Further, the rubbing protrusions 3a and 3b can be configured as an integral oval or oval cylindrical body in which these end portions are continuous with each other.

  In any case, the rubbing projections 3a and 3b are in close contact with the drilling wall created by the excavation of the excavating rod 1a when rotating in the ground while rotating together with the excavating rod 1a. Thus, the thickness (thickness) is such that the hole wall can be compacted while being rubbed in the direction of expanding the hole diameter over a predetermined width when pulled up. The shape and size of the rubbing protrusions 3a and 3b are determined in consideration of the driving torque of the excavating rod 1a, the sliding resistance of the rubbing protrusions 3a and 3b against the hole wall surface, the prevention of partial collapse of the ground, and the like.

The construction procedure of the hydraulic solidifying material liquid replacement column performed using the hydraulic solidifying material liquid replacement column building apparatus 1 having such a configuration is basically the same as the procedure shown in FIG. That is, in the hydraulic solidifying material liquid replacement column building apparatus 1 in which the drilling head 2 having the discharge port 2b leading to the flow path 1d is connected to the lower end portion of the drilling rod 1a having the hydraulic solidifying material liquid flow path 1d. The excavation rod 1a is rotated to a predetermined depth of the ground while rotating, and then the excavation rod 1a is pulled up while rotating or non-rotating while discharging the hydraulic solidified liquid from the discharge port 2b of the excavation head 2, and inside the drilling hole Is filled with hydraulic solidifying material liquid to build a hydraulic solidifying liquid replacement column.
At this time, the hydraulic solidifying material liquid may be discharged from the discharge port 2b of the excavation head 2 when the excavation rod 1a is rotated and excavated to a predetermined depth of the ground.

  In this case, the rubbing projections 3a and 3b rotate together with the excavation rod 1a when the ground is excavated by the rotation of the excavation rod 1a and when the ground is pulled up. For this reason, the outer surface (outer peripheral surface) of the rubbing projections 3a and 3b is pressed against the drilling hole wall drilled to approximately the same diameter as the drilling rod 1a by the lower part of the drilling head 2 and the drilling rod 1a. To do. Specifically, the rubbing protrusions 3a and 3b are rubbed against the hole wall surface in a direction of expanding the hole diameter while rotating. In response to the pressing force at the time of rubbing, the ground around the drilling wall is compressed in the aforementioned direction over a predetermined thickness, and the density of the earth and sand at these compression sites is remarkably increased. Therefore, the compressive strength of the ground with increased density, the shear strength is significantly increased, receiving the side pressure associated with the construction of the hydraulic solidifying material liquid replacement column in the adjacent part other than the ground with the increased strength, Even if earth and sand movement or distortion occurs, the drilling can sufficiently counter these.

FIG. 3 is a front view showing a modification of the embodiment. In this example, the upper and lower ends of the rubbing projections 3a and 3b provided on the excavating rod 1a in the embodiment shown in FIG. 1 are tapered 5, and the other is the same as in the embodiment shown in FIG. Similar components are denoted by the same reference numerals, and other detailed description is omitted.
According to the configuration of this embodiment, since the upper and lower ends of the rubbing protrusions 3a and 3b are tapered 5, the digging resistance during digging can be reduced, and hole wall shaving during pulling can be prevented.

  4 and 5 are a perspective view and a cross-sectional view of a main part showing a hydraulic solidifying material liquid replacement column building apparatus according to another embodiment of the present invention. This hydraulic solidifying material liquid replacement column building apparatus 1A includes a drilling rod 1a having a conical head 2 connected to the lower end. In the present embodiment, the conical head 2 has a conical shape whose diameter decreases downward, and a spiral blade (spiral excavation blade) 2a is fixed on the peripheral surface thereof, and does not overlap with the spiral blade 2a. A hydraulic solidifying material liquid discharge port 2b is provided at the position. A backflow prevention valve 2c for preventing backflow of earth and sand is attached to the discharge port 2b. Further, the discharge port 2b communicates with the inner pipe 1d which is a flow path of the hydraulic solidifying material liquid.

  A pair of rubbing protrusions 4a and 4b having a circular arc cross section are integrally and symmetrically arranged on the lower outer periphery of the excavating rod 1a over a predetermined length h along the excavating rod 1a. The rubbing protrusions 4a and 4b rub the inner peripheral wall surface of the drilling hole in the direction of expanding the drilling diameter when the excavating rod 1a is advanced and pulled up, and compact the ground around the inner peripheral wall surface of the drilling hole while expanding the drilling hole diameter. Therefore, having a certain length h along the excavating rod 1a can be rubbed and compacted over a wide range of hole lengths, and can be reliably rubbed and compacted. Although it is preferable, if it is too long, rotation resistance, excavation resistance and pulling resistance increase, which is disadvantageous in that a large construction machine is required. The length h is taken into consideration. The length h of the rubbing protrusions 4a and 4b can be exemplified as a preferable length that is about 1 to 2 times the diameter D of the excavation rod 1a.

  In addition, the diameter of the drilling hole (thinning thinning) is less likely to occur over the entire length of the drilling hole, and the position generated by the ground properties, the depth of the drilling hole, the spacing between adjacent replacement columns, etc. changes. It is not constant. Therefore, the position of the excavation rod 1a where the rubbing protrusions 4a and 4b are provided only needs to be provided at a position that can cover the range in which the diameter of the drilling hole is reduced. However, since it is difficult to specify the range in which the diameter is reduced for each drilling hole, the lower part of the drilling rod 1a is rubbed over almost the entire length except for the part near the hole bottom of the drilling hole. It is preferable because it can be hardened and the ground around the inner peripheral wall surface of the hole can be strengthened. These rubbing projections 4a and 4b are provided integrally with the excavation rod 1a, and are made of a metal equivalent to the excavation rod 1a and the conical head 2, for example, steel. The rubbing projections 4a and 4b are firmly attached to the excavation rod 1a by using fastening members such as bolts and nuts or welding. The rubbing protrusions 4a and 4b have the same shape and size, and have the same thickness as a whole.

  These rubbing projections 4a and 4b are pressed together with a drilling wall of a drilling hole created by excavation of the drilling rod 1a during excavation of the ground while rotating together with the drilling rod 1a, and a predetermined region (thickness of the drilling wall) Further, the wall thickness is such that it can be compacted (compressed) while being rubbed in the extending direction over the length in the vertical direction). Further, the width and the vertical length h of the rubbing protrusions 4a and 4b are determined in consideration of the driving torque of the excavation rod 1a, the sliding resistance of the rubbing protrusions 4a and 4b against the hole wall surface, prevention of partial collapse of the ground, and the like. It is done. The length h of the rubbing protrusions 4a and 4b can be exemplified as a preferable length that is about 1 to 2 times the diameter D of the excavation rod 1a.

  The construction procedure of the hydraulic solidifying material liquid replacement column by the hydraulic solidifying material liquid replacement column building apparatus 1A having such a configuration is basically performed in the same manner as described above. That is, the excavation rod 1a is rotated to a predetermined depth of the ground, and then the excavation rod 1a is pulled up while being rotated from the discharge port 2b of the excavation head 2 while rotating the excavation rod 1a. A hydraulic solidifying liquid replacement column is constructed by filling with a hard solidifying liquid.

  In this case, at the time of excavation by the excavation rod 1a and at the time of pulling up by rotation, the outer wall surface of the rubbing projections 4a and 4b (the outer wall surface of the rubbing projections 4a and 4b immediately after excavation is drilled to a diameter approximately equal to the diameter of the excavation rod 1a). The outer peripheral surface) is pressed in a sliding contact state. For this reason, the rubbing protrusions 4a and 4b are rubbed against the hole wall surface in the direction of expanding the hole diameter. In response to the pressing force at the time of rubbing, the ground around the drilling wall is compressed in the aforementioned direction over a predetermined thickness, and the density of the earth and sand at these compression sites is remarkably increased. Therefore, the compressive strength and shear strength of the ground with increased density are remarkably increased, and the external force applied from a part other than the ground with the increased strength, for example, the hydraulic solidifying material liquid of the column has not yet solidified. In the meantime, even if other hydraulic solidifying liquid replacement columns are subjected to side pressure when they are installed in the vicinity, even if earth or sand movement or distortion occurs, the strength of the drilling wall can be countered by the stress. It becomes possible.

  In the above-described embodiment, if the left and right corners P that continue from the surface of the rubbing projections 4a and 4b to the left and right side surfaces become corners P that continue at an acute angle from the surface to the side surface, The corners P of 4a and 4b scrape off the earth and sand on the wall surface of the drilling hole, and the rotational resistance of the excavation rod 1a also increases. Therefore, the corners P of the rubbing projections 4a and 4b are preferably obtuse angles, It is more preferable to use a surface (including a tapered surface). Accordingly, the inner peripheral wall surface of the hole can be smoothly slid in contact with the inner peripheral wall surface of the hole, the rotational resistance can be reduced, and the rubbing effect can be enhanced. The rubbing protrusions 4a and 4b are rotated together with the excavating rod 1a, contact with the drilling wall of the drilling hole created by the excavation of the excavating rod 1a, and solidify the ground while rubbing it in a direction extending over a predetermined width. The strength of the drilled wall can be increased. Further, the rubbing protrusions 4a and 4b provided on the excavation rod 1a are arbitrarily set to one or three or more as necessary. In the case of one, it is important to take measures so that the excavation rod 1a does not operate eccentrically during rotation. In the case of three or more, the penetration resistance during excavation is increased or the work is attached to the excavation rod 1a. Adopted in consideration of complexity and cost increase.

FIG. 6 is a perspective view showing a modification of the embodiment shown in FIGS. In this example, the upper and lower ends of the rubbing projections 4a and 4b provided on the excavating rod 1a in the embodiment shown in FIG. 4 are tapered (including an arc shape) 5, and the others are the embodiments shown in FIG. Since the configuration is the same as that of the embodiment, the same components are denoted by the same reference numerals, and other detailed descriptions are omitted.
According to the configuration of this embodiment, since the upper and lower ends of the rubbing protrusions 4a and 4b are tapered (including arc-shaped) 5, the digging resistance during digging can be reduced, and the hole wall shaving during lifting is reduced. Can be prevented.

The excavation head 2 may be provided with a vertical protrusion along the circumferential surface of the conical head instead of the spiral blade 2a. FIG. 7 is a perspective view of a main part showing the excavation head provided with a vertical protrusion along the circumferential surface of the conical head. The excavation head 2 of this embodiment is a conical head having a conical shape whose diameter decreases downward, and a plurality of vertical protrusions 12 along the peripheral surface are provided on the peripheral surface of the conical head 2 ( In this example, four) are provided, and a hydraulic solidifying material liquid discharge port 2b is provided in a portion not overlapping with the protrusion 12. The rest is the same as in the above embodiment.
When the ridge 12 rotates and digs into the ground, the ridge 12 excavates the ground and improves the digging performance. Therefore, it is sufficient that at least one ridge 12 exists. improves. In this example, the case where four pieces are provided on the outer periphery at equal intervals is shown.
The protrusion 12 is not particularly limited as long as it can excavate (stir) the ground when rotating and excavating into the ground, and in this example, a rectangular plate-like member is formed on the circumferential surface of the conical head 2. The case where it stands in the vertical direction (axial direction) along is shown. The maximum rotation diameter of the ridge 12 is set to be equal to or less than the rotation diameter of the excavation rod 1a.

  In the excavation head 2 of this embodiment, since it has a conical shape provided with the vertical ridges 12 along the circumferential surface, the ground is excavated well by the ridges 12, and the ridges 12 excavate. Since the earth and sand guided by the ridge 12 can be excavated into the ground while being moved upward along the peripheral surface of the conical head 2, the excavation performance is improved and the workability is improved.

  As described above, according to the present embodiment, the hydraulic solidified material in which the excavation head 2 having the discharge port 2b leading to the flow channel 1d is connected to the lower end portion of the excavation rod 1a having the flow channel 1d of the hydraulic solidification material liquid. Using a liquid replacement column construction device, excavating to a predetermined depth in the ground while rotating the excavating rod 1a, and then pulling up the excavating rod 1a while rotating or without rotation, and filling the drilling hole with a hydraulic solidifying material liquid When the hydraulic solidifying material liquid replacement column is constructed, the rubbing projections 3a, 3b, 4a, 4b provided on the excavating rod 1a are rubbed in the direction of expanding the drilling diameter. Is rubbed against the wall surface of the hole.

  Thereby, the density of the surrounding ground of a drilling wall surface is raised within predetermined thickness, and the ground strength in this site | part is raised. Therefore, the hydraulic solidification material liquid is filled in the borehole expanded in this way, and when the hydraulic solidification material liquid is not yet solidified, another hydraulic solidification is performed on the surrounding ground near the drilling position. Even if the material replacement column may be installed, it is possible to suppress excessive reduction or deformation of the bore diameter filled with hydraulic solidification material liquid, and the reduction or deformation of the bore diameter has occurred. Can also ensure the planned diameter. As a result, it is possible to prevent or reduce the excessive increase or overflow of the hydraulic solidifying material liquid accompanying the diameter reduction of the hole. Further, after the excavation rod 1a is pulled out from the drilling hole, the outer diameter of the solidified liquid replacement column that is filled is kept within the length and outer diameter size in the planned design even if the ground near the drilling is elastically returned. Can do. Such an effect can be achieved quickly and smoothly by filling the drilling hole with the hydraulic solidifying material liquid by a simple operation of rubbing the rubbing projections 3a, 3b, 4a and 4b against the drilling wall surface during the drilling operation of the drilling rod 1a. Can be implemented. Such an effect can be obtained with a simple and inexpensive configuration in which rubbing projections 3a, 3b, 4a, and 4b are provided on the outer periphery of the excavation rod 1a.

  The present invention expects a reduction in the diameter of the drilling hole formed by excavating the ground, and pressurizes in the direction of expanding the drilling diameter, thereby strengthening the ground around the drilling hole and reducing the drilling diameter. It has the effect of being able to build a hydraulic solidified material liquid column having a cross-sectional area and strength as planned, and is useful for a hydraulic solidified material liquid replacement column building method, a hydraulic solidified material liquid replacement column building device, and the like.

1 Hydraulic solidifying material liquid replacement column construction device 1a Drilling rod 1d Inner pipe (flow path)
2 Conical head
2a Spiral blade 2b Discharge port 2c Backflow prevention valve 3a, 3b, 4a, 4b Rubbing protrusion 5 Upper and lower end taper portion 12 of rubbing protrusion

Claims (5)

Using a hydraulic solidifying material liquid replacement column building apparatus in which a drilling head having a discharge port leading to the flow path is connected to a lower end portion of a drilling rod having a hydraulic solidifying material liquid flow path, the ground is rotated while rotating the drilling rod. After drilling to a predetermined depth, the drilling rod is rotated or discharged without rotation while discharging the hydraulic solidification liquid from the discharge port of the drilling head, and the hydraulic solidification liquid is filled into the drilling hole and hydraulic. A hydraulic solidifying liquid replacement column building method for building a solidifying liquid replacement column,
A rubbing protrusion is provided at a predetermined position on the side surface of the lower portion of the excavation rod over a predetermined length along the excavation rod, and at least when the excavation rod is advanced, the inner diameter wall surface of the hole is expanded by the rubbing protrusion. The hydraulic solidifying material liquid replacement column construction method is characterized in that the ground around the inner peripheral wall surface of the drilling hole is compacted while being rubbed in the direction in which the drilling hole is expanded.   2. The hydraulic solidifying material liquid replacement column building method according to claim 1, wherein the rubbing protrusion has a semicircular cross section. A hydraulic solidifying material liquid replacement column building apparatus in which a drilling head having a discharge port leading to the flow path is connected to a lower end portion of a drilling rod having a flow path of hydraulic solidifying material liquid,
A rubbing projection for rubbing the inner peripheral wall surface of the drilling hole in a predetermined direction on the side surface of the lower portion of the drilling rod in the direction of expanding the drilling diameter, and compacting the ground around the inner peripheral wall surface of the drilling hole while expanding the drilling diameter, A hydraulic solidifying material liquid replacement column building apparatus, characterized in that the hydraulic solidifying material liquid replacement column building apparatus is provided over a predetermined length along the line.   4. The hydraulic solidifying material liquid replacement column building apparatus according to claim 3, wherein the rubbing protrusion has a semicircular cross section.   The excavation head is a conical head that protrudes downwardly in a conical shape. On the peripheral surface of the conical head, vertical ridges along the peripheral surface or earth and sand excavated when the excavation rod rotates forward 5. The hydraulic solidifying material liquid replacement column building apparatus according to claim 3, wherein the hydraulic solidifying material liquid replacement column building apparatus has a spiral blade in a direction to be pushed up and a discharge port of a hydraulic solidifying material liquid leading to the flow path of the excavation rod. .

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