JP2020020251A - Ground injection method - Google Patents

Abstract

To provide a ground injection method which enables sure infiltration and solidification in heterogeneous ground.SOLUTION: A ground injection method that injects a solution type grout includes 1) setting silica concentration obtaining a strength required with a predetermined density using soil to be an object, 2) adjusting a silica grout blended liquid having a gelation time (GT) corresponding to pH or an additive using the predetermined silica concentration, 3) mixing the blended liquid with field soil, and measuring underground gelation time (GT), 4) setting a solidification object soil amount in unit stage by an assumed injection hole interval, an injection method and a one-injection stage length, 5) setting the injection amount from the solidification object soil amount in the unit stage, and setting injection time (H) per unit stage from the injection speed in the infiltration possible limit, and 6) setting blending prescription of the gel time (GT) and the silica concentration of the injection liquid satisfying GT>H≥GTsor GT>GT≥H according to a ground situation, an injection hole interval, and an injection amount per unit stage.SELECTED DRAWING: Figure 18

Description

  The present invention embeds an injection pipe in a drilled hole formed in the ground and injects an injection material into the ground around the hole wall, thereby improving the water stopping performance of the ground, increasing the strength, preventing liquefaction, etc. And a ground injection method for implementing the method.

  In recent years, ground injection methods include deep excavation work, seismic reinforcement, and long-term work associated with large-scale construction, etc. However, reliable ground improvement effects and economic efficiency have been required. Therefore, as for the injection technique, it is necessary to develop not only the chemical stability of the injection material itself, but also an injection technique that allows infiltration and injection between soil particles and enables economical construction. In particular, due to the frequent occurrence of earthquakes, it has a wide range of infiltration and solidification properties and a certain quality, as well as reliable infiltration and solidification, and it is economical over a wide area without the injected liquid deviating outside the specified injection area or the ground surface There is a demand for an injection method and an injection material which can be improved. However, ground injection is usually an improvement of a heterogeneous ground consisting of alternate layers of different soil layers, and the more extensive the ground improvement, the more easily the injected liquid deviates, making it difficult to reliably infiltrate and solidify a predetermined area.

  The present invention has been completed in order to meet those demands, and further develops the prior inventions (Patent Documents 1, 2, and 3) by the present inventor who pay attention to columnar permeation injection that enables low-pressure injection with a large discharge amount. It solves the problem of the columnar infiltration method by enabling a wide range of homogeneous infiltration and consolidation, and reduces deviations outside the predetermined planned injection range under ground conditions consisting of complex soil layers. Thus, an economical columnar infiltration injection method has been completed which ensures formation of a consolidated body having a large consolidated diameter corresponding to the injection amount.

  The inventor of the present invention pays attention to the fact that column infiltration can be injected from a large infiltration source as compared with spherical infiltration and that it can infiltrate between soil particles with a large discharge rate and low pressure (Figs. The inventions of Documents 1, 2, and 3 have already been made.

Japanese Patent No. 4827109 Japanese Patent No. 5942161 Japanese Patent No. 3509744

The problems of the prior invention will be described below.
For example, the injection pipe described in Patent Literature 1 has a columnar space in which the outer circumference of an injection pipe main body is covered with a water-permeable material having a certain thickness such as a woven fabric, a nonwoven fabric, or a mat, and further covered with a water-permeable sheet. The injection liquid discharged from the injection pipe discharge port upon injection is easily spread from the columnar infiltration source to the entire surface, and penetrates into the ground to enable columnar injection. is there.

  This method has an excellent effect that large-diameter low-pressure infiltration can be performed under relatively homogeneous ground conditions.However, in the case of non-homogeneous ground, primary injection causes hard and soft surroundings of the injection pipe, If the size is too large, there is a problem that the splitting of the seal grout surrounding the injection tube tends to be partial.

  Further, there is a problem that the injection liquid is clogged in the space such as the mat and the subsequent injection liquid is difficult to be injected. These make it particularly difficult to inject the suspension. In addition, if the columnar penetration length is increased, the seal grout in the weak part of the drilled wall or the seal grout is broken, and the injection liquid tends to concentrate on that part. Tended to be difficult.

  Further, the invention of Patent Document 2 is an invention that solves the above problem of Patent Document 1. That is, the injection pipe is in close contact with the outer circumference of the injection pipe main body and the injection pipe main body having a plurality of injection material discharge ports in the pipe axis direction, and both ends in the pipe axis direction are fixed in a sealed state on the outer circumference of the injection pipe main body, And a cylindrical elastic covering (elongated rubber slit tube) having a circular cross-section having a plurality of injection material injection slits along a pipe axis direction of the injection pipe at a position not overlapping with the plurality of injection material discharge ports, The entire surface of the cylindrical elastic covering body (rubber slit tube) is brought into close contact with the outer peripheral surface of the injection pipe main body so that a rubber tensile force is generated over the entire length in a tangential direction of a circular cross section by elastic force. Then, the injection material discharge port is sealed, and the injection material sent to the injection tube main body is formed by a spray pressure into a seal grout between the injection tube main body and the hole wall along a pipe axis. Around the hole wall from the drill Columnar penetrate into the ground.

  Further, when the liquid supply to the injection pipe main body is stopped, the entire surface of the cylindrical elastic covering body (rubber slit tube) is brought into close contact with the outer peripheral surface of the injection pipe main body by its elastic force, thereby closing the injection material discharge port. The injection material sprayed out of the elastic elastic body is configured not to flow back into the injection pipe main body.

  However, according to a further study by the present inventors, the above-mentioned invention is excellent when the ground is homogeneous, but the formation of cracks in the pipe axial direction of the seal grout due to the injection pressure is weak in the ground around the seal grout. In some cases, when the periphery of the seal grout surrounding the elastic coating is solidified by the primary injection material, or when the cylindrical elastic coating is long and located in a layer with different ground conditions, Injection from the injection slit with the liquid pressure that overcomes the elastic pressure of the elastic coating material causes partial breakage of the seal grout, and it is difficult for predetermined cracks to occur over the entire length of the seal grout outside the elastic coating material understood.

  Also, the invention by the present applicant described in Patent Document 3 is to insert an injection pipe provided with a plurality of bag packers at intervals in a drilled hole in the ground, and to form a drilled wall between the bag packers and the injection pipe. The present invention relates to a soil injection method and an injection pipe device for injecting an injection material into the ground through a space between the injection material and the injection pipe device, and in particular, forming a dense soil packer in which the injection material hardly penetrates into the ground area around the bag packer. The present invention relates to a ground injection method and an injection pipe device that allow an injection material to penetrate more widely into a soil layer to be injected in a horizontal direction, and reduce the number of drilling holes by increasing a drilling interval (injection hole interval). However, this method forms a columnar compact having a large pore diameter on homogeneous ground, and achieves an extremely excellent improvement effect. However, when the ground is heterogeneous, the injected liquid may easily deviate to a rough layer or the ground surface.

  The present invention embeds an injection pipe in a drilled hole formed in the ground and injects an injection material into the ground around the hole wall, thereby improving the water stopping performance of the ground, increasing the strength, preventing liquefaction, etc. It is an invention related to the ground injection method for carrying out, to solve the problem that it is easy to deviate from the coarse soil layer to the outside of the predetermined injection area when trying to obtain a large consolidation diameter by taking a long columnar infiltration section, It is possible to form large consolidated bodies economically and surely form a compacted body corresponding to the injection amount by infiltration between soil particles without deviating to a coarse soil layer or the ground surface under the ground conditions consisting of a complex soil layer. Is made possible.

  The present inventors have positioned the outer tube in the seal grout, and even if the coating film covering the outer tube is long, and even if there is a hard or soft layer on the ground outside the seal grout, and the cement grout, etc. The elastic coating film swells with surface pressure even on the ground after the primary injection of high grout, and the seal grout of the length corresponding to the section of the elastic coating film is surely cracked. To infiltrate the section of the predetermined coating film, and also to enable the compound injection by repeated injection, primary injection, and secondary injection to solve the problem of the prior invention and meet the requirements described in the section of the background art. The following technology is provided.

Hereinafter, the present invention will be described with reference to the claims and the drawings.
(Soil injection device 01) Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 6, Figure 7, Figure 8, Figure 9
A ground injection device (A: injection pipe device) provided with an injection pipe for injecting an injection material into the ground around the drill hole by being installed in a drill hole (2 ... drill hole) formed in the ground,
The injection pipe is an outer injection pipe (4 ... outer injection pipe) fixed in a seal grout (3 ... seal grout) filled in a drilled hole, and a single pipe inserted into the outer injection pipe and slid up and down or An injection inner pipe (5 ... injection inner pipe) having a plurality of injection liquid feeding pipes (11 ... injection liquid feeding pipe);
The infusion outer tube has an infusion solution outer tube discharge port (6... Outer tube discharge port) and the outer circumference of the outer tube covers the infusion solution outer tube discharge port in the tube axis direction, and has a large number of surface discharge portions distributed in the tube axis direction. One or a plurality of long elastic covering films (8 long elastic covering films) that cover a predetermined length in a circular cross section having (7 ... surface discharging portion), and the long elastic covering film is The both ends of the predetermined length are closed to the injection outer tube with a fixing material (9 ... fixing material),
The surface discharge unit is opened when pressurized by the elasticity of the long elastic coating film, and is closed when not pressurized. The injection inner tube includes a plurality of inner tube packers (up and down) that expand and contract by fluid pressure. 10 ... Inner pipe injecting part (13 ... Inner pipe injecting part) consisting of inner pipe outlet (12 ... Inner pipe outlet) sandwiched by inner pipe packer)
When injecting the infusion solution, the inner tube injection portion is located at the outer tube discharge port of the outer injection tube, and the inner tube packer is expanded to expand the inside of the long elastic coating film (14 ... in the long elastic coating film). ), The seal grout is split over a predetermined length by swelling the long elastic coating film with surface pressure, and the injection liquid is injected into the ground from the surface discharge portion. And ground injection equipment.

  The length of the sleeve of the check valve is usually 8 to 10 cm, but the long elastic coating film is longer than the usual sleeve, preferably 20 cm to 3000 cm, more preferably, depending on the ground conditions and the distance between the injection holes. 30-200 cm is used.

(Soil injection device 02) Fig. 7, Fig. 8, Fig. 9, Fig. 11 (B), Fig. 12 (B), Fig. 14 (B), Fig. 15 (C)
In a ground injection device (A: injection pipe device) provided with an injection pipe for installing in a drill hole (2 ... drill hole) formed in the ground and injecting an injection material into the ground around the drill hole,
The injection pipe is an outer injection pipe (4 ... outer injection pipe) fixed in a seal grout (3 ... seal grout) filled in a drilled hole, and a single pipe inserted into the outer injection pipe and slid up and down or An injection inner pipe (5 ... injection inner pipe) having a plurality of injection liquid feeding pipes (11 ... injection liquid feeding pipe);
The outer tube for injection is provided with a plurality of outer tube outlets (6... Outer tube outlet 2) in the tube axis direction and a predetermined length covering the outer periphery of the outer tube in a circular cross section in the tube axis direction. One or a plurality of long elastic coating films having a surface discharge portion (7... Surface discharge portion) which covers the outlet and is open when pressurized in which circumferential slits are distributed and closed when not pressurized. (8: a long elastic coating film) and an outer tube discharge port (19: inside and outside of a bag packer) having a check valve (20: a check valve inside a bag packer) provided at a position different from the long elastic coating film The long elastic coating film is composed of a bag packer (18: bag packer) covering the discharge port of the pipe, and the long elastic coating film is closed at both ends of a predetermined length by a fixing material (9: fixing material). Forming inside
The injection inner pipe (13) has an inner pipe discharge port (12 ... inner pipe discharge port) sandwiched between a plurality of inner pipe packers (10 ... inner pipe packers) that expand and contract by fluid pressure. … Inner tube injection section)
When injecting the infusion liquid, after injecting the consolidated material into the bag packer from the outlet of the bag outer tube and swelling around the injection tube, the inner tube injection part is located at the outer tube outlet of the injection outer tube, Inflating the inner tube packer to discharge an injection material into the long elastic coating film (14... Inside the long elastic coating film) to swell the long elastic coating film with surface pressure. Wherein the seal grout is cleaved over a predetermined length, and an injection liquid is injected into the ground from the surface discharge portion.

In the above, the material of the bag packer may be a cloth packer or a rubber packer which becomes cylindrical when expanded. Alternatively, they may be used in layers. Of these, when the cloth packer presses the consolidated material, the size of the diameter is limited to the size of the cylinder as long as the cloth has strength not to break. Therefore, if it is set to a diameter larger than the drill hole diameter and installed in the ground, the cloth packer not only closes the drill hole wall but also becomes larger and compresses the periphery of the drill hole wall to form an underground packer. I do.
In addition, the cloth packer presses the solidification material and leaches a part of the solidification material from the seam of the thread to solidify the surrounding soil, forming an underground packer substantially larger than the size of the bag cylinder. Prevents the infusate from escaping upward and allows it to penetrate horizontally to form a large compact.
The cloth material of the bag packer includes geotextiles such as geowoven (woven fabric and woven fabric), geononwoven (nonwoven fabric), and geonit (knitted fabric). The size and strength of the seam of the cloth material used for the bag packer can be confirmed by injecting the suspension into the bag (usually about 1 MPa) and seeping out the suspension. In a test of the present inventor in actual injection, a bulging packer having a diameter of 20 cm was formed in a hole drilled with a calcium silicate seal grout having a diameter of 10 cm, and a solid component having a diameter of approximately 30 cm was formed due to a leaching component of a suspension around the packer. A good underground packer was formed.

  On the other hand, the rubber packer unequally swells when the consolidated material is press-fitted, and is liable to be partially damaged. Therefore, by overlapping the outside with a cloth packer, the size of the diameter of the packer can be controlled. The position of the bag packer may be above or below the section of the coating film, or above or below the section of the coating film, depending on the ground conditions and the purpose of the injection, and may be one or more, or one at the top.

  In any case, the bag packer not only prevents the infusion liquid from flowing out in the vertical direction of the outer tube together with the seal grout, but also forms a consolidation diameter larger than the drilling diameter and densifies the surrounding soil, Both the primary injection and the secondary injection prevent the outflow in the vertical direction, and the secondary injection liquid can permeate the soil particles over a wide range substantially horizontally in a predetermined injection stage. In addition, one or an arbitrary number of outlets 1 for the outer tube of the bag are provided at the position other than the bag and the elastic coating film on the outer tube to which the bag is attached, so that the packing effect in the vertical direction of the bag and the primary injection material can be obtained. By using together the effect of preventing the deviation from the planned injection range from the coarse soil layer by the above, the permeable secondary injection material can surely permeate between the soil particles into the predetermined injection region.

  Further, the bag packer may be divided, and the outer pipe discharge port 1 may be provided between the upper and lower bag packers to perform the primary injection. The outer tube discharge port 1 may be limited to this position (FIG. 13 (c)). In particular, when silica grout (FIGS. 18 and 19) in a non-alkali region to be described later is secondarily injected within the limit speed shown in FIG. 24, the injection amount set in Table 7 (a) is set in Table 7 (b) or claim 1. If the injection is performed with the formulation set in ~ 4, the solidified body corresponding to the predetermined injection amount at a low pressure (Fig. 23 (b)) will be applied to the ground surface in the permeation gelation behavior shown in Figs. The solidification between soil particles can be reliably performed without deviating to a coarse layer. The effect of this primary injection is the same in claim 1.

(Soil injection device 03) Figures 1 to 21
A ground injection device (A) provided with an injection pipe for injecting an injection material into the ground around the drilled hole by being installed in a drilled hole (2 ... drilled hole) formed in the ground by the ground injection devices 01 and 02. ... injection tube device)
The injection pipe is an outer injection pipe (4 ... outer injection pipe) fixed in a seal grout (3 ... seal grout) filled in a drilled hole, and a single pipe inserted into the outer injection pipe and slid up and down or An injection inner pipe (5 ... injection inner pipe) having a plurality of injection liquid feeding pipes (11 ... injection liquid feeding pipe);
The outer tube of the injection tube has an outer tube outlet 1 (16 ... outer tube outlet 1) covered with a check valve (15 ... outer tube outlet 1 check valve) made of an elastic sleeve and an elastic coating film (8 ... an outer tube discharge port 2 (6 ... outer tube discharge port 2) covered with an outer tube discharge port 2 (6 ... outer tube discharge port 2). A surface discharge unit (7: surface discharge unit) which covers the injectate outer tube discharge port in the axial direction of the outer tube on the outer circumference of the outer tube, and which is open when pressurized in which circumferential slits are distributed and closed when not pressurized. ) Comprising one or a plurality of elastic coating films (8 ... elastic peritoneal membranes) covering a predetermined length in the tube axis direction in a circular cross-section having a predetermined length at both ends. The inside of the elastic coating film closed by the fixing material (9 ... fixing material)
The injection inner pipe (13) has an inner pipe discharge port (12 ... inner pipe discharge port) sandwiched between a plurality of inner pipe packers (10 ... inner pipe packers) that expand and contract by fluid pressure. … Inner tube injection section)
When injecting the injection liquid from the outer tube outlet 2, the inner tube inlet is located at the outer tube outlet of the outer tube to inflate the inner tube packer to expand the inside of the long elastic coating film (14). ... the injection material is pressed into the long elastic coating film), and the long elastic coating film swells due to surface pressure, thereby splitting the seal grout over a predetermined length and simultaneously injecting the injection liquid from the surface discharge portion. A ground injection device for injecting into the ground through splitting of the seal grout.

From the outer tube outlet 1, prior to the secondary injection from the outer tube outlet in the coating film, perform a primary injection, and inject a coarse soil layer of a different soil layer or a soil layer that easily deviates in advance. Homogenize the ground to be injected.
For example, if the ground is made up soil layer of 10 ⁰ ~10 ^-4 cm / sec in hydraulic conductivity, the primary infusion, the primary injection can ^{penetrate, 10 0, 10 -2 cm /} sec soil layer of the order of To the order of 10 ⁻³ cm / sec to 10 ⁻⁴ cm / sec to homogenize the ground. Then, if a non-alkali silica grout having a long gelation time and good permeability is injected, the injection amount set at the injection interval in Table 7 (a) can be adjusted within the limit speed in FIG. If the injection is performed with the formulation set in the items 19 to 22, the predetermined injection amount permeates a large permeation range by the permeation behavior of FIGS. 14 to 16, 17, and 19, and the injection liquid almost moves from the predetermined injection region as it is. It solidifies in a predetermined range with the lapse of gelation time. Also, in FIGS. 1, 2 and 3, the outer tube discharge port 1 does not have to be a case where primary injection is performed from the outer tube discharge port 2 from the long elastic coating film.

  In addition, the outer pipe discharge port 1 is installed only in the portion near the ground surface of the injection outer pipe, and the secondary injection from the outer pipe discharge port 2 is performed by previously injecting the suspension or the primary injection liquid of instantaneous grout. It is also possible to prevent the material from deviating from the ground surface. The number of the long elastic coating films provided on the outer tube for injection may be only one or plural at intervals depending on the ground conditions and the purpose of injection. For example, an outer pipe discharge port 1 may be provided at an uppermost part of the outer injection pipe, and an outer pipe discharge port 1 may be provided at an arbitrary interval below the outer pipe. Also, an arbitrary number of outer injection tubes 1 may be provided, and a coating film may be provided at one location below. For example, when a viscous soil layer is present, pulsation injection of suspension injection or instantaneous injection from the outer pipe discharge port 1 is performed, and in a soil layer composed of a sand layer and a plurality of soil layers, columnar penetration from the coating film is preferable. .

(Soil injection device 04) Figures 2 and 3
In the ground injection apparatus 01, 02, 03, the injection liquid discharged from the inner pipe injection section pressurizes the inside of the elastic coating, swells the elastic coating film at the surface pressure, splits the seal grout over a predetermined length, and breaks the surface. A ground injection device wherein the ground is injected from a discharge part through a split of the seal grout.

  In the above, the upper and lower sides of the elastic coating film are caulked with a fixing material. The position is formed by crimping the upper and lower ends of the long coating film to form the inside of the long coating film by pressurizing the infusate and swelling the long coating film to form a long coating film with seal grout. Can be split over the length of Further, by dividing the long coating film into several pieces and caulking, an arbitrary number of unit lengths of the coating film can be set. In the case where the end portion is closed by the bag packer or the outer tube discharge port 1, it is needless to say that the crimping portion is not required to be provided as the crimping portion.

(Soil injection device 05) Figs. 2 (c) to (e), (c ') to (e'), Figs. 4, 7, 12, and 13
In the ground injection apparatus 01 to 04, the outer pipe discharge port is located between the upper and lower packers of the inner pipe injection section in the section of the elastic coating film, and the slit of the surface discharge section has one slit. Ground injection characterized by having a length in the direction of Mcm, a width of 1 mm, and a total area smaller than the total area of the inner pipe discharge ports in the section of the elastic coating film, assuming that N pieces are distributed. apparatus.

  In the above, the section of the elastic coating refers to a section which is crimped up and down with a bonding agent such as an adhesive or a metal ring. Also, in FIGS. 1 and 2, the inside of the long elastic coating film 14 of the long elastic coating film 8 is expressed with a space for explanation, but actually, the elastic film of the long elastic coating film 8 Closely adhered. Alternatively, a water permeable space holding material 25 may be provided in the long elastic coating film (FIGS. 2 (c) to 2 (e)). The outer tube discharge port may be provided with a band-shaped elastic check valve 17 'on the surface. In this case, the check valve may be open at both upper and lower ends, or may be swaged up and down so as to make a cut on the circumference at the center so that the injection liquid is jetted. In this case, the injected injection liquid penetrates into the entire length of the coating film through the water-permeable space holding material, rapidly pressurizes the inside of the elastic coating, swells out the entire length of the long elastic coating film by surface pressure, and seal grout. Split.

  The slit 7 of the surface discharge part 7 is linearly closed in a tangential direction of the circumference of the outer tube. If the total surface area of the N slits distributed in the covering section is smaller than the total area of the discharge ports 12 of the inner pipe in that section, the pressure of the infusate flowing into the covering initially causes the peritoneum to seal grout. To cause the seal grout to split over the entire length of the section at the surface pressure. In the process of bulging, the slits become larger, and the injection liquid penetrates into the ground throughout the section through the split.

The slit has a length Mcm in the circumferential tangential direction of the tube axis, usually 1 to 3 cm, and N surface discharge portions are distributed.If the width when opened is converted to 1 mm, the total surface area of the slit at the time of opening is 0.1. MN / cm ² . Assuming that the cross-sectional area of one of the inner tube discharge ports 12 is acm ² and b, the relation may be 0.1 MN (cm ³ / cm ² ) ≦ ab. In the following drawings, the water permeable space holding material is omitted, but if there is no space holding material, the outer pipe diameter will be small, so the drilling diameter will be small, and the existing building will be curved below the ground. This has the advantage that drilling is easier.

(Soil injection device 06) Figs. 3 (f) to (h), Fig. 5, Fig. 6, Fig. 8, Fig. 9, Fig. 11
In the ground injection devices 02 and 03, the injection liquid discharged from the outer pipe discharge port check valve is press-fitted along the outer pipe surface over the entire length of the long elastic coating film, and the coating film is applied by surface pressure. A seal grout surrounding the outer periphery of the long elastic coating film by swelling by pressing, causing a predetermined length of splitting of the coating section, and injecting liquid being injected from the split into the surrounding ground. Infusion device.

(Soil injection device 07) Figs. 3 (f) to (h), Fig. 5, Fig. 6, Fig. 8, Fig. 9, Fig. 11
In the ground injection devices 03 and 06, the outer pipe discharge port 2 is provided with a check valve (17... Outer pipe discharge port check valve) composed of a band-shaped elastic sleeve whose upper and lower ends are opened. Is injected into the elongated elastic coating film from above and below the strip-shaped elastic sleeve from the outer tube discharge port along the axial direction of the outer tube, and the surface pressure of the elongated elastic coating film is increased. Wherein the seal grout is split over a predetermined length, and the ground is injected from the surface discharge portion through the split of the seal grout.

  In the above description, the water permeable space holding material 25 may be provided in the elastic coating film as in FIGS. 2 (c ′), (d ′), and (e ′). As a result, the inside of the elastic coating film is rapidly pressed, and the seal grout is split by the surface pressure.

(Soil injection device 08) (Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15)
A ground injection device characterized in that, in the ground injection devices 03 and 07, either the outer pipe discharge port 1 or the outer pipe discharge port 2 is set as a discharge port of a primary injection material.

The primary injectable material may be injected from the outer tube outlet 1 or may be injected from any portion of the outer tube outlet 2 without the outer tube outlet 1. 11, 12, 13, without the outer tube ejection port 1, from L _1-1 ... L _4-1 by injecting the primary infusion material L _{1 to 2} ... L _4-2 from the secondary grout May be injected, or in FIG. 14 (a), the primary injection material may be primarily injected from the outer injection tube discharge port 1 located in the seal grout, and then the secondary injection material may be injected in accordance with the primary injection region. You may. Further, in FIG. 14 (b), after injecting the consolidated material into the bag packer of the outer pipe of the injection pipe located in the seal grout, the primary injection material is injected from the outlet 1 of the outer pipe of the injection pipe, and then the secondary injection material is injected. The injection material can be injected from the injection pipe discharge port 2, and the secondary injection can be performed in the region where the primary injection has been performed.

(Soil injection device 09) Fig. 4 (b), Fig. 6, Fig. 7 (b), Fig. 9, Fig. 11, Fig. 14, Fig. 15
In the ground injection device of the ground injection devices 01 to 08, the injection inner pipe has a plurality of injection liquid feed pipes (11A, 11B... A plurality of inner tube injection portions sandwiched by inner tube packers, each of which discharges an injection material into a plurality of long elastic coating films (14 ... in the long elastic coating films). Wherein the seal grout is split from the plurality of long elastic coating films simultaneously or selectively over a predetermined length and injected into the ground. (See (0046) below)

(Soil injection device 10) FIGS. 1 to 5, FIG. 11, FIG. 12, FIG. 13, FIG. 14, and FIG.
In the ground injection device 03, the injection outer pipe is provided with a check valve (15... Opposite to the outer pipe discharge port 1) composed of an outer pipe discharge port provided at a position different from the long elastic coating film and a stretchable sleeve covering the discharge pipe. A ground injection device having one or more outer pipe primary injection material discharge ports (16... Outer pipe discharge port 1) provided with a stop valve).

(Soil injection method 11) Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15
Using the ground injection devices 01 to 10, the injection inner tube inserted into the injection outer tube fixed in the seal grout is slid to discharge the injection liquid into the long elastic coating film, and from the surface discharge portion. A ground injection method, comprising swelling the long elastic coating film at a surface pressure to split the seal grout over a predetermined length and injecting an injection liquid into the ground.

(Soil injection method 12) (Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15)
In the ground injection method 11, a secondary injection material is injected into a region into which the primary injection material has been injected.

(Soil injection method 13) (Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15)
Ground injection method 11, 12 ground injection method,
After placing the outer injection pipe in the seal grout in the drilled hole, inject the primary injection material through the inner injection pipe, fill the coarse layer or the easily deviating layer, and then set the injection liquid delivery pipe line. Slide the inner injection tube having one or more inner injection tubes into the outer injection tube to position the inner tube injection portion in the section of the one or more long elastic coating films, and supply the secondary injection material from the injection inner tube. It is characterized in that the seal grout surrounding the coating film from the surface discharge portion is split into a predetermined length and injected into the ground by discharging simultaneously or selectively into the long elastic peritoneum of one section or a plurality of sections. Ground injection method.

(Soil injection method 14) (Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15)
A ground injection method according to any one of the ground injection methods 11 to 13, wherein a secondary injection is superimposed and injected into a region where the primary injection has been performed.

(Soil injection method 15) (Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15)
In the ground injection method of the ground injection method 11 to 14, the plurality of inner pipe injection portions are positioned so as to discharge different injection materials into different long elastic coating films, respectively, and are simultaneously or selectively injected into the ground. Ground injection method.

(Soil injection method 16)
In the ground injection method of the ground injection method 11 to 15, any one or both of the seal grout and the primary injection material is the following consolidated material, and the strength of the consolidated body is 10 kg / cm2 or less in uniaxial strength. Ground grouting method to be either grout. See (0082) to (0105) below.
(1) A suspension grout containing calcium aluminate as an active ingredient.
(2) Grout containing a polymer thickener as an active ingredient.
(3) Suspended grout containing clay as an active ingredient.
(4) Suspended grout containing cement / bentonite as an active ingredient.

(Soil injection method 17)
In the ground injection method of ground injection methods 11 to 16, the primary injection material grout is a suspension type grout or a solution type grout having a short gelation time. See (0108) to (0121) below.

(Soil injection method 18)
In the soil injection method 11 to 17, the injection material injected from the long elastic peritoneum is a solution-type grout, a suspension-type grout, or an injection material having better permeability than the primary injection material. See (0108) to (0121) below.

(Claim 1)
A ground pouring method that satisfies the following conditions in a ground pouring method for improving a ground by pouring a solution grout into the ground. See (0108) to (0121) below.
1) Set the silica concentration to obtain the required strength at a predetermined density using the target soil.
2) Using a predetermined silica concentration, prepare a silica grout mixture having a gelation time (GT ₀ ) corresponding to the pH or additive.
3) Mix the mixture with the soil at the site and measure the gelation time (GT _S0 ) in the soil.
4) Set the amount of soil to be consolidated at the unit stage based on the assumed injection hole interval, injection method, and one injection stage length.
5) Set the injection amount based on the amount of soil to be consolidated at the unit stage, and set the injection time (H) per unit stage from the injection speed within the permeation limit.
6) Depending on the ground condition, injection hole interval, and injection amount per unit stage,
Formulation is set up based on the gel time (GT ₀ ) and silica concentration of the infusate satisfying GT ₀ > H ≧ GT _S0 or GT ₀ > GT _S0 ≧ H.

(Claim 2)
In the ground injection method for improving the ground by injecting the solution type grout into the ground, the gel time of the injected liquid is GT ₀ , the gel time of the mixed liquid and the injected liquid is the underground gel time, GT _S0 , and the injection time per stage is H Then, these values are set in the following ranges, and the ground injection method reduces the deviation of the injected material outside the injection range. See (0108) to (0121) below.
(1) The injection speed should be within the limit permeation injection speed.
(2) Injection hole spacing or consolidation diameter L = 1.0-3.0m
(3) Injection rate per minute q = 1 to 30 L / min.
(4) 1 stage length: 0.33m ~ 3.0m
(5) Injection time per stage H: 4.4 to 10,000 minutes However, the injection time (H) can be shortened in consideration of workability at the site and shortening of the latter period.
(6) Air gelation time GT ₀ : 10 minutes to 10,000 minutes (7) Air pH (pH ₀ ): 1 to 10
(8) Silica concentration: 0.4 to 40% (% by weight)
(9) Soil gel time GT _S0 : 10 minutes to 3000 minutes Here, within the critical penetration rate refers to a penetration rate lower than the splitting / penetration rate.

(Claim 3)
3. The soil injection method according to claim 1, wherein the solution type grout is injected into the ground to improve the ground. See (0108) to (0121) below.
Injection hole interval: 1m-3m
Soil gel time (GT _S0 ) = 10-3000 minutes Injection rate (discharge rate per minute) = 1-30 l / min
However, the injection speed is within the limit penetration injection speed.
Injection volume per stage = 132l to 10,800l
Injection time per stage (H) = 4.4 minutes to 10,800 minutes β = H / GT _S0 = 10800/10 to 4.4 / 3000 = 1080 to 0.001, preferably 1080 to 1

(Claim 4)
The method for injecting ground into the ground according to any one of claims 1 to 3, wherein the injection is columnar infiltration and the following conditions are satisfied. See (0108) to (0121) below.
132l to 10,800l injection volume per stage
Injection speed 10l-30l / min
Injection time per stage 4.4 minutes to 1080 minutes Soil gelation time (GT _S0 ) = 10 to 3000 minutes β = H / GT ₀ = 1080/10 to 4.4 / 3000 = 108 to 0.001, preferably β = 108 to 1

(Claim 5)
In the ground injection method according to any one of claims 1 to 4, after injecting the primary injection material, prior to injecting the secondary injection material, press-fitting water or the injection material to split the seal grout, and between the soil particles of the ground. A ground injection method characterized by injection at an injection speed within a limit injection pressure.

(Claim 6)
6. The ground injection method according to claim 5, wherein after the water or the primary injection material is injected, the secondary injection material is subsequently injected at an injection speed within a limit injection pressure.

  In the present invention, the permeation injection is performed by splitting the seal grout and then injecting at an injection speed in the permeation and splitting injection region in FIG. 18, preferably within the range of the limit injection speed (curve D). It is necessary to increase the pressure (curve (a)). The seal grout may be split by pumping water, or may be split with a low-viscosity silica grout having a long gelation time to prevent dilution of the injection liquid. After splitting at the curve (a), it is possible to subsequently switch to the curve (D) and to inject the permeable injection material.

(Claim 7)
In Claims 1 to 6, the pH of the silica injection solution is 1 to 10, and one or more of colloidal silica or water glass and one or more of an acid or a salt as a reactant. When the silica injection liquid is composed of colloid, water glass and acid, the ratio of the silica concentration caused by the silica colloid to the silica concentration caused by the water glass is 100: 0 to 0: 100, and the silica concentration Is a silica grout selected from a composition of 0.4 to 40 wt%, a molar ratio of silica of 2.0 to 100, and a gelling time of 10,000 minutes from instantaneous setting. (Figures 12 and 13)

(Claim 8)
8. The ground injection method according to claim 7, wherein the silica injection liquid is injected into the ground by point injection, multipoint injection, columnar injection, simultaneous injection of multiple points, simultaneous injection of multiple stages, or selective injection. (Fig. 14, Fig. 15, Table 7)

  In FIG. 15 (c), the outer tube discharge port 1 is used for point injection, the injection from the long coating film 8 is used for columnar injection, and the simultaneous injection or the selective injection from a plurality of inner tubes to a plurality of injection stages is performed. This corresponds to stage simultaneous injection or selective injection. Simultaneous injection or selective injection from the outer tube outlet 1 or the outer tube outlet 2 can be performed by a collective control system using a plurality of injection pumps.

  11. The ground injection method according to the ground injection method 11, wherein the filling of the filler into the bag packer is performed after filling the seal grout in the drilled hole or during the seal grout filling step.

(A) is a front view of the outer injection tube, and (B) is a cross-sectional view of the injection tube. (C), (d), (e), (c '), (d') and (e ') show that the injection liquid discharged from the outer tube discharge port swells the long coated surface and splits the seal grout. FIG. 4 is a side view showing that the rubber is injected into the ground through the split. (F), (g), and (h) are injection liquids discharged from the outer pipe discharge port of another type, the injection liquid swells the long coated surface, splits the seal grout, and is injected into the ground through the split. It is a side view which shows that it is performed. (B) after injected from the inner tube 5 in L ₁ having a single infusate flow path of the injection method of Figure 2 (c) to (e), to be injected pulling the inner tube to L ₂ sectional view showing, indicating the (b) be likewise injected from the flow path 11A to L ₁ from the injection inner tube with two infusate flow path, is co-injected or selectively injected from the channel 11B to the L ₂ It is sectional drawing. FIG. 4 is a cross-sectional view showing that L is injected into L from an injection inner tube having one injection flow channel by the injection method of FIGS. Injected similarly from the flow path 11A from the injection inner tube with two injection channels of the L _2, it is a sectional view showing that the co-injection, or selectively injected from the channel 11B to L _1. 5 (a) and 5 (b) are cross-sectional views of an injection tube in which a bag packer 18 is provided on the outer tube of the injection method of FIG. FIG. 6 is a cross-sectional view of an injection tube in which a bag packer 18 is provided on the outer tube of the injection method of FIG. FIG. 7 is a cross-sectional view of an injection tube in which a bag packer 18 is provided on the outer tube of the injection method of FIG. FIG. 7 is a cross-sectional view of an injection tube using a bag packer (Patent Document 3). (A) is a side view of the injection tube structure shown in FIG. 4 (B), which has a discharge port for the primary injection material and an elastic coating film on the outer tube, and (B) shows a bag packer 18 in (A). FIG. (A) is a side view of the injection pipe structure of FIG. 6 having a discharge port of the primary injection material and an elastic coating film on the outer pipe, and (B) is provided with a bag packer 18 in (A). It is a side view of an injection pipe. FIG. 6 is a side view in a case where an outer tube discharge port 1 is provided between upper and lower bag packers to perform primary injection. (A) is a cross-sectional view showing a construction procedure when using the injection pipes of FIGS. 11 (A) and 12 (A), and (B) is a case where the injection pipes of FIGS. 11 (B) and 12 (B) are used. It is sectional drawing which shows the construction procedure. FIG. 4 is a cross-sectional view of an injection system for performing simultaneous injection or selective injection from a plurality of injection tubes using an injection tube device having a long elastic coating film. It is a graph of the gel time of the seal grout which consists of calcium aluminate. It is a graph of the uniaxial compressive strength of grout which consists of calcium aluminate. It is a graph of pH and gel time of the silica solution of non-alkaline silica grout. It is a graph which shows the relationship of pH of non-alkaline silica grout, gel time, and silica concentration (in a figure). It is a graph which shows the example of the gel time of a non-alkaline silica grout homogel and a sand gel. 5 is a graph showing examples of pH (PH ₀ ), aerial gel time (GT ₀ ), and soil gel time (GT _S0 ) of non-alkali silica grout. 4 is a graph showing the relationship between the mixing ratio of CB lumps in a silica solution and the gel time (minutes) when CB lumps are mixed in a silica solution having a pH of 2. It is a graph of the estimation calculation of the spherical penetration radius (Maag's equation) and the estimation calculation of the columnar penetration radius (Theim's equation). It is a graph which shows the example of a critical osmosis injection speed. It is explanatory drawing of the behavior of the infiltration consolidated soil in the soil of a solution type non-alkali silica grout.

  In addition to the description of the means for solving the problems, the features of the present invention will be described below with reference to the drawings.

(1) The sealing grout is split into predetermined lengths by the surface pressure caused by the swelling of the long elastic coating film, and the injection liquid is injected.
As shown in FIGS. 1 to 6, the injection outer tube covers an outer tube outlet (6... Outer tube outlet) and an outer tube outlet on the outer periphery of the outer tube in the tube axis direction. One or a plurality of long elastic coating films (8: long elastic peritoneal membrane) that cover a predetermined length in a circular cross section having a large number of surface discharge portions (7: surface discharge portions). The long elastic coating film is fixed at both ends of a predetermined length to the injection outer tube with a fixing material (9... Fixing material) to form the inside of the long elastic coating, and the surface discharge portion is formed of the elastic material of the long elastic coating film. Opens when pressurized and closes when not pressurized.

  In the present invention, the surface discharge portion is a tangential lateral slit having a circular cross section of the outer injection tube. Since the lateral slit does not lose the tension in the circumferential tangential direction of the elastic coating film, the liquid injected from the outer tube discharge port can swell into the seal grout due to the surface pressure of the entire coating film by the following method To On the other hand, in the case of the longitudinal slit, the tensile force in the tangential direction is reduced, and it becomes difficult to swell by the surface pressure.

FIGS. 2 (c), (d), (e), FIGS. 4 (a) and 4 (b) are explanatory diagrams relating to the ground injection devices 04 and 05.
A plurality of slits in the tangential direction of the circumference of the circular outer tube are distributed at a plurality of locations on the surface discharge portion of the long elastic coating film, and the slit is in close contact with the outer tube by the tension. Therefore, even if the slit is opened by pressurizing with the injection liquid from inside, the tension in the tangential direction hardly decreases. And since both ends in the axial direction of the coating film are fixed to the outer tube, the injection liquid discharged into the coating film from the injection inner tube through the outer tube discharge port, the slit length Mcm of the surface discharge portion, Assuming a width of 1 mm and N pieces, if the total area is smaller than the total area of the outer tube discharge port, the peritoneum first comes into contact pressure on the seal grout side and expands on the outer seal grout. Put out. As a result, many cracks occur in the entire length L of the seal grout due to the surface pressure of the coating film, and cracks continuously occur not only in the horizontal direction but also in the vertical direction to cause splitting of the coating section (L).

  Because the slit has almost no width at first, the injection liquid discharged from the outer tube first pressurizes the inside of the elastic coating film, and then the slit that increases in pressure starts to open. It is. At first, the opening width is increased from zero to 1 mm or more, and the injected liquid penetrates into the split caused by the surface pressure and penetrates the surrounding ground. If the total area of the slits in the surface discharge part is equal to or larger than the outer tube discharge port, the seal grout is more broken by the jet pressure from the outer tube discharge part than by the surface pressure of the coating film. The splitting is more localized than splitting due to surface pressure.

The following is a description of FIGS. 3 (f), (g), (h), FIGS. 5 and 6.
In FIGS. 3 (f), (g) and (h), the outer tube discharge port 6 is a check valve (17: outer tube discharge port check valve) formed of a band-shaped elastic sleeve having upper and lower ends opened. The injection liquid discharged from the outer pipe discharge port check valve is ejected from the telescopic sleeve (17) along the outer pipe surface as shown by the arrow, so that the injection liquid is injected into the elongated elastic coating film ( 14) The entire section (L) of the seal grout is press-fitted over the entire length (L) and pressurizes the inside of the coating film (14) to swell as a surface into the seal grout layer (3). A large number of splits occur in the vertical direction as well as in the horizontal direction, which causes a predetermined length of splitting of the covered section (L), from which the injection liquid is injected into the surrounding ground Will do.

  As a result, even if the outside of the seal grout is affected by the hardness and softness of the soil and the primary injection material, and even if the covering section is long, the seal grout can be split by the surface pressure of the peritoneal membrane over the entire length of the predetermined section. Column penetration of a given length became possible.

  Also, as shown in FIG. 7, FIG. 9, FIG. 11, FIG. 12, and FIG. 13, the injection liquid according to the soil layer is injected from the inside of the coating film by caulking with a fixing material according to the soil layer. can do.

(2) Since the injection pipe is installed in the seal grout, and since the outer pipe discharge port in the long elastic coating film is covered with a stretchable sleeve, the outside of the seal grout is removed from the surface discharge part. The liquid injected into the outer tube or the liquid injected from a nearby injection tube can be prevented from flowing back into the outer tube discharge port. Further, it is possible to repeatedly inject the injection liquid from the surface discharge port. Also, even in the case of a suspension, the outer tube outlet is not closed. Therefore, in a complicated soil layer, prior to the secondary injection, the primary injection is performed to prevent the soil layer from deviating to the coarse soil layer and the ground surface, and the secondary injection allows a predetermined range of interpenetration between soil particles.

(3) Fig. 4 (b) and Fig. 6 show that the seal grout can be simultaneously or selectively spread over a predetermined length from a plurality of elastic coating membranes by using an injection inner pipe having a plurality of liquid feed pipes (11A, 11B). It can be split and injected into the ground (ground injection method 11).
For this reason, a plurality of columnar injections can be performed at the same time, so that a low discharge rate and a low pressure per unit stage can be used as a whole, and a large discharge rate can be achieved at a low pressure and a rapid penetration injection can be performed at a low pressure. Now you can get great economic benefits. 4 and 7 show the packer fluid flow path 21, but are omitted in other figures. The injection inner pipe may be a parallel pipe having a plurality of flow paths, a double pipe, or a triple pipe including a packer flow path.

(4) The ground is usually formed with different soils in layers. On the other hand, in order to surely improve the ground, a solution-type injection material with a long gelation time and excellent permeability must be infiltrated and injected between the soil particles. No. Injectable material having good permeability tends to deviate to a rough layer or the ground surface in a heterogeneous ground, and as a result, penetration between soil particles into a fine layer is hindered, and it becomes difficult to infiltrate a wide range of soil particles. In the present invention, prior to injecting the injection liquid having good permeability, the injection material having low permeability such as suspension grout or flash-setting grout is primarily injected to homogenize the ground to obtain the injection material having good permeability. It is possible to improve the ground extensively over the entire target ground by suppressing the deviation from the injection range by reliably performing the compound injection by the next injection.

1) Since the outer tube of the injection outer tube is closely attached to the outer tube discharge port with a long elastic coating film, the primary injection material can be injected from the outer tube discharge port 2 through the surface discharge portion of the elastic coating film, or the elastic coating can be performed. It can be injected into the ground from the outer pipe primary injection material discharge port 1 located other than the covering film. The primary grout injected into the ground by the seal grout and the elastic coating film can repeatedly inject the secondary grout any number of times without closing the secondary grout discharge port. (Fig. 11 (a), Fig. 12 (a))

2) For the primary injection, slide up and down the injection inner pipe from the outer injection pipe to inject over the coarse soil layer or the entire injected soil layer, and then inject the injection material with good permeability through the injection inner pipe. be able to. The primary injection can be performed from the elastic coating film through the outer tube outlet 2.

3) Also, the primary injection material is injected from the outer tube primary injection material discharge port 16 provided at a position different from the long elastic coating film 8 through the injection inner tube, and then the secondary injection is performed from the long elastic peritoneum 8. Material can be injected. (Fig. 1 (a) and Figs. 4 to 15)

4) Also, using an injection pipe having a plurality of inner pipe injection parts, the plurality of inner pipe injection parts are positioned so as to discharge the primary injection material and the secondary injection material respectively into different long elastic coating films. At least at the same time, the injection inner pipe can be slid into the injection outer pipe so as to be overlapped simultaneously or selectively or overlapped, and injected into the ground (Fig. 4 (b), Fig. 6, Fig. 7 (b), Fig. 9, Figures 11, 14, and 15).

  When the primary injection material is injected from the long elastic coating film, the outer tube primary injection material discharge port may not be provided. Further, the outer pipe primary injection material may be located only in the uppermost portion or in the coarse soil layer which is likely to deviate depending on the ground conditions. Further, the long elastic coating film 8 may be provided only at the uppermost portion or at a position that requires long permeation depending on the ground conditions.

  Next, a ground injection apparatus and a ground injection method in which a bag packer is provided in the above-described injection pipe will be described. The invention of Patent Document 3 inserts an injection pipe provided with a plurality of bag packers at intervals in a hole in the ground, and injects an injection material through a space between a hole wall and an injection pipe between the bag packers. The present invention relates to a soil injection method and an injection pipe device for injecting into a ground, and in particular, to form a dense underground packer in which an injection material is hardly penetrated into a ground region around the bag packer, so that the injection material can be horizontally injected. The present invention relates to a ground injection method and an injection pipe device that allow a hole to penetrate more widely into a layer and make a drilling interval (injection hole interval) wider to reduce the number of drilling holes. This method forms a columnar compact having a large pore diameter in homogeneous ground, and achieves an extremely excellent improvement effect. However, when the ground is uneven, the injected liquid may deviate to a rough layer or the ground surface.

  When the ground to be injected is laminating, the hydraulic conductivity is usually larger in the horizontal direction than in the vertical direction. Conventionally, when injecting an injectable material into such ground and consolidating the ground, a plurality of bags forming a bag packer are attached at intervals to an injection pipe tube wall, and the inside and the top and bottom of the bag are attached. Using an injection pipe device provided with a discharge port opening between adjacent bags, insert this injection pipe device into a drilled hole provided in the ground, and then from the discharge port opening inside the bag. This is a technique in which a bag is filled with a curable suspension and inflated to form a bag packer, and an injection material is injected from a discharge port opened between vertically adjacent bags to consolidate the ground. .

  In this case, according to the above-described known technique, a gap formed between the injection pipe and the drilled wall is blocked by vertically adjacent bag packers to form an independent space between these bag packers. The injection material is injected into the ground through the through hole. This method ensures that when the ground is relatively homogeneous, it penetrates in a columnar manner and forms a large consolidated diameter. However, when the ground is composed of soil layers with different permeability, and when the injection stage length is long, the injection liquid tends to concentrate on the soil layer with good permeability, so the injection stage length must be shortened. No.

  In the present invention, a hole is filled with seal grout, the injection pipe is buried, a bag body is provided in the injection pipe method, and a primary injection and a secondary injection are made possible. Even under the condition, the interval between the injection holes is widened, the injection length per stage is widened, and the ground improvement having a predetermined improvement effect uniformly without deviating from the injection target is enabled.

  The present invention has solved the above-mentioned problem by attaching a bag packer to the above-mentioned injection pipe installed in a seal grout. FIGS. 7, 8, 9, 11 (b), 12 (b), 14 (b)

(A) The bag packer of the outer tube restrains the axial direction of the long elastic coating film with a diameter larger than the hole diameter, and at the same time, the density of the surrounding soil is increased. Therefore, the elastic coating film swells in the lateral direction and splits the seal grout by surface pressure, and the injected liquid permeates laterally without going to the ground surface. Accordingly, a large-diameter solid body is formed with a large interval between the injection holes.

(B) Large diameter permeation injection is possible by lengthening the elastic coating film or increasing the number of sections of the unit coating film. Fig. 11 (b), Fig. 12 (b)
(C) Departure from the injection area even if the section of the coating film is long because the ground can be homogenized by the primary injection from the outer pipe primary injection material discharge hole or the elastic coating film without deviating to the ground by primary injection. Can be prevented. For this reason, permeation between soil particles by secondary injection is possible. Fig. 11 (b), Fig. 12 (b)

(D) Since the bag packer with a hard upper part and the underground packer with high density are formed, the length of the long elastic coating film is increased, and the surface of the elastic coating film is formed using a low-strength seal grout. The pressure can easily split the seal grout. FIGS. 7, 8, 9, 11 (b), 12 (b), 14 (b)

(5) The seal grout according to the present invention protects the hole and prevents the infused liquid from entering the elastic coating film from another injection pipe or another injection stage. In order to make the seal grout easily split over the entire length by a swelling of the covering film when the injection material is injected from the long elastic peritoneum, the seal grout is made of one of the following materials. using 1 MN / m ² or less in a uniaxial strength, further preferably a low intensity of 0.5 mN / m ² or less. (Soil injection method 12).

1) Suspended grout containing calcium aluminate as an active ingredient.
2) Grout containing a high-molecular polymer as an active ingredient.
3) Suspended grout containing clay as an active ingredient.
4) Suspended grout containing cement and bentonite as active ingredients.

  Cement grout has high alkali and high strength with a pH of 13 or more, and it is difficult to cause a predetermined length of splitting of the seal grout even with the surface pressure of the elastic coating film. Further, a high alkali easily deteriorates the solution-type silica grout of the secondary injection material. For this reason, the seal grout used in the present invention has a low alkali of pH 12 or less and a uniaxial compressive strength of 10 kg / cm 2 or less, preferably 5 kg / cm 2 or less. An injection material having these characteristics is excellent not only as a seal grout but also as a primary injection material. The reason for this is that, since it is low in alkali, not only the silica grout is prevented from deteriorating in combination with the solution-type silica grout, but also the elastic coating film easily splits the seal grout over its entire length with a surface pressure.

Among the above grouts, examples of seal grout containing calcium aluminate as a main component are shown below.
The suspension-type ground consolidating material containing calcium aluminate as a main component has a capability of consolidating by a hydration reaction, and is a calcium aluminate (12CaO · 7Al ₂ O) usually used as a quick setting material for cement. _{3, CaO · 2Al 2 O 3} , calcium halo aluminate 3CaO · _Al 2 _{O 3,} etc., or further these and a halogen element and a solid solution, for example, suspension composed mainly of 11CaO _· 7Al ₂ O 3 _· CaF, etc.) It means a turbid ground consolidation material, and further includes a material obtained by mixing or melting such a calcium aluminate with an inorganic sulfate such as gypsum or sodium sulfate. Calcium aluminate and slag may be the main components. The binder has a pH of about 10.8 or less, has relatively low strength, and tends to split.

A test example of a seal grout containing calcium aluminate as a main component suitable for the seal grout according to the present method will be described below. The gel time can be reduced by reducing the amount of water in Table 2.
(1) Composition Table-1
(2) Formulation example Table-2
(3) Gel time Figure 16
(4) Compressive strength Fig.-17

Next, examples of grout containing a high-molecular polymer as an active ingredient will be described.
The high-molecular polymer as the seal grout used in the present invention must be a material for stabilizing the drilled wall.

  The high-molecular polymer does not adversely affect the consolidation property and consolidation strength of the obtained injection material, and is, for example, an organic high-molecular-weight polymer, specifically, for example, a polysaccharide or a derivative thereof, Natural gums, water-soluble synthetic high molecular substances and the like can be mentioned.

  Examples of the polysaccharide or a derivative thereof include alkali metal salts such as sodium carboxylmethylcellulose (cmc), hydroxyethylcellulose, sodium starch glycolate, sodium starch phosphate, sodium alginate, propylene glycol alginate, and sodium caseinate. Examples of the class include gum arabic, alginic acid, casein, guar gum, gluten, roasted bean gum, and the like, and examples of the water-soluble synthetic polymer include polyvinyl alcohol and sodium polyacrylate.

  Since such a polymer has a high viscosity by adjusting its concentration, it can be used as a seal grout by itself, but it can be mixed with a silica compound, bentonite, cement, or the like to impart plasticity and provide an arbitrary consolidation time or Strength and pH value can be obtained. Table 3 shows examples of high-molecular polymers.

These can be used as seal grout as a stabilizing solution for drilling walls as a high-viscosity solution, but by mixing with bentonite, it becomes a stable solution for drilling walls with high viscosity using low-concentration polymer. It can be used as seal grout.
Of course, it may be used by mixing with bentonite, a cement solution or a silica solution.

  By mixing a polymer with a silica compound, a seal grout having a predetermined viscosity, gelation time and strength can be produced. Table 4 shows examples of the solution-type silica compound. Table 5 shows an example in which a high-molecular polymer and a silica compound are mixed. The concentration of the polymer or silica compound is determined in such an amount that the resulting injection material exhibits a viscosity of 2 to 40 cps, preferably 2 to 20 cps. Specifically, the amount of the high-molecular polymer is preferably in the range of 0.1 to 5% by weight in the injection compounding liquid.

  Table 5 shows examples of the viscosity of the silica compound to which the high-molecular polymer is added.

  An arbitrary gel time can be obtained by adding an additive such as an acid or a salt thereto.

The additives are shown below, but the invention is not limited thereto.
Hydrochloric acid HCl 35% Reagent 1st grade Aluminum chloride AlCl3.6H2O Reagent 1st grade Magnesium chloride MgCl2 6H2O Reagent 1st grade Potassium chloride KCl Reagent 1st grade No.3 Water glass manufactured by Asahi Denka Kogyo Co., Ltd.

  Table 6 shows examples of the gel time of the viscosity when the additive is added.

  Table 6 is an example of a long gel time. The gel time can be reduced to several minutes by increasing the concentration of the high molecular polymer or the salt, or by increasing the silica concentration. Further, by adding calcium silicate or bentonite thereto, the gel time, viscosity and plasticity can be arbitrarily adjusted according to the ground conditions, drilling conditions and construction conditions.

The injection material containing clay as an active ingredient flows into the drilled hole as a plastic grout and is filled.However, after filling, it becomes a gelled state and no fluidity occurs, suppressing the fluidity and dilution by groundwater and stabilizing the pore wall. I do. Thereafter, the injection liquid is injected into the long coating from the inner tube, and the coating film surface presses the seal grout. If the applied pressure exceeds the shearing force of the plastic gel, the gel becomes fluid or mixed with the silica compound. If the strength of the solidified product exceeds the strength, the swelling of the long elastic coating film is facilitated, and along with the injection of the injection liquid, the entire length of the predetermined section is split so that the injection liquid penetrates into the ground. Can be. It should be noted that a kaolin-based clay having a lower pH and a nearly neutral seal grout can be obtained as compared with bentonite as the clay.
For other seal grouts, cement and bentonite can be reduced in strength and pH by increasing their concentration and the ratio of bentonite to cement, and in the case of clay, the clay concentration can be increased or decreased and the clay can be changed depending on the type of clay. The strength, pH and plasticity of the gel can be adjusted, but details are omitted here.

In the above, the filling of the packing material into the bag packer is performed after the filling of the seal grout in the drilled hole or when the compaction strength of the seal grout is large, the bag packer is completely expanded and then the bag packer is greatly expanded. Since it is difficult to perform the sealing grouting, the sealing grouting can be performed during the filling process.
Similarly, the filling of the holes in the seal grout can be performed by any of the following procedures.
1) The injection pipe is provided in a seal grout filled in a drill hole, and the seal grout is used after the injection pipe is installed in the drill hole, or further injects a bag packer with a solidifying material. After swelling, the hole is filled from the injection tube into the hole.
2) Using an injection pipe device having at least one bag body forming a bag packer on the injection pipe pipe wall during drilling and a discharge port for injecting the injection liquid into the ground on the pipe wall below the bag body ( 1) a step of forming a bag packer by filling a bag with a curable suspension and inflating the bag; (2) a step of filling a seal grout in a bore; and (3) a discharge port provided below the bag. In the step of breaking the seal grout from the outlet and injecting the injection liquid into the ground, the seal grout is filled with the curable suspension in the bag body and then filled or cut into the hole from the injection pipe. The filling of the seal grout into the hole and the filling material into the bag packer are continuously performed from the injection pipe.
3) Suspended grout shall be used for the seal grout, and the primary suspended grout will be injected into the ground while filling the grout with the seal grout.

  The injection method using the injection device of the present invention is excellent in durability, and penetrates widely between soil particles with a long gelation time, and penetrates a wide range, and hardly deviates outside a predetermined injection region or the ground surface. It is required to have characteristics. In addition, it is necessary that the behavior leading to gelation is compatible with the injection by the injection device.

  As such an injection material, an organic water glass or silica grout in a middle to acidic region (non-alkali silica grout) is desirable as a solution type injection material. As the suspension grout, a cement grout, a cement bentonite grout, and a slag grout are preferable.

  Examples of the non-alkali silica grout include an acid-neutral water glass grout (silica sol grout) obtained by removing the alkali of water glass with an acid, and a colloidal silica obtained by further increasing the particle size of active silica deionized by subjecting the water glass to ion exchange treatment. And non-alkali silica and metal silica made of a composite silica obtained by mixing colloidal silica, water glass and an acid. In addition, since grout exhibiting plasticity is obtained by adding a non-alkali silica solution, cement or slag, and a carbonate (baking soda, sodium carbonate), it can be used as a seal grout.

The relationship between the pH of non-alkali silica grout, the gelation time, and the silica concentration is shown in FIGS.
From FIG. 19, it can be seen that the non-alkali silica can have a long gelation time up to 10,000 minutes, and FIG. 19 shows that even if the injection solution is diluted with groundwater, it gels and maintains its consolidation. In addition, as shown in Fig. 19, when the non-alkali silica is injected into the ground near neutral pH, the pH shifts to the neutral direction even in acidic silica grout with a long gelation time, and the gelation time is shortened and gelation occurs. (Figs. 20 and 21).

FIGS. 20 and 21 show the relationship between the aerial gel time (GT ₀ ) of the non-alkali silica grout that has reached the purpose of injection, the aerial pH (PH ₀ ) of the infusate, and the gel time GT _{S0 in} the soil on the actual ground.
The soil gel time (GT _S0 ) refers to a mixture of the soil and the injection fluid from the ground to be injected or the pH of a sample in which the injection fluid has penetrated the soil. When the pH of the ground and PH _S, in the vicinity PH _S = 5 to 8.

According to the study of the present inventor, even if the soil gel time (GT ₀ ) is shorter than the injection time (H ₀ ) required for wide-area infiltration, as shown in FIG. It was found that the infiltration and consolidation region expanded while exceeding the skin of No. 3 to form a consolidated body having an injected soil amount corresponding to a predetermined injected amount. FIG. 22 shows an example of shortening the gelation time when cement / bentonite is used as the primary injection and non-alkali silica grout is injected as a secondary injection. When the amount of the primary injection is large in the ground, the gelation time of the secondary injection is shortened, so that the deviation of the secondary injection material out of the injection region is reduced. However, a compact corresponding to a predetermined injection amount is formed by the behavior shown in FIG. In this example, the injection liquid with a gel time of 205 minutes is reduced to almost 10 minutes by the influence of cement bentonite.

  Next, the method of the present invention for forming a large consolidation diameter using a wide injection interval without departing from a predetermined range will be described how to mix an injection solution using the apparatus of the present invention. Using a non-alkaline silica grout with a long air gelation time (GT0) and a low injection rate (q (L / min)), injecting time (H) over a wide range of injection amount to prevent deviation from the injection range It was found that the solidification occurred while reducing the amount.

In this case, assuming that GT ₀ ≧ H ≧ G _S0 , it was found that as shown in FIG. 25, the pH permeated over the infused solution that was about to gel to the ground on the neutral side. In this case, as the pH of the non-alkaline injection solution increases, the injection solution begins to gel, and then the injection solution with a low pH climbs over it, consolidating while repeating the increase in pH and gelation. By making use of the behavior of expanding the region, the injection hole is widened, and even if the injection range is widened, it is possible to solidify a predetermined region.

In order to infiltrate between soil particles, injection must be performed at an injection speed q (L / min) lower than the limit of the split injection region as shown in FIG. If a point injection is used, a high injection pressure is required to increase the penetration radius as shown in FIG. However, if columnar permeation is used as in the present invention, as shown in FIG. 23 (b), it can be seen that permeation can be performed at a low pressure even if the height of the columnar permeation source is increased and the injection speed is increased under the same conditions.
In addition, although the amount of soil received in Table 7 is actually a cylinder, it was calculated as a prism for convenience.

  An injection liquid for forming a solidified body corresponding to a predetermined injection amount without deviating outside a predetermined range even at a large injection hole interval after consolidating the injection ground by homogenizing the ground by the above method. Must apply the prescription. The procedure for that is described below (Table 7).

1) Set the silica concentration to obtain the required strength at a predetermined density using the target soil.
This is because the strength of the sand gel formed by silica grout in the non-alkali region is almost determined by the silica concentration.
2) Using a predetermined silica concentration, prepare a silica grout mixture having a gelation time (GT ₀ ) corresponding to the pH or additive.
3) Mix the solution with the soil in situ and measure the gelation time in soil (GT _S0 ).
4) Set the amount of consolidated soil per unit stage based on the assumed injection hole interval, injection method, and one injection stage length. (Table 7 (a))
5) Calculate the predetermined injection amount from the amount of consolidated soil in the unit stage, and set the injection time (H) per unit stage from the injection speed within the permeation limit. (Table 7 (a))
6) Depending on the ground conditions,
GT ₀ > H ≧ GT _S0 or GT ₀ > GT _S0 ≧ H
A formulation is set that consists of the gel time (GT ₀ ) of the injection solution and the silica concentration (Table 7 (b)).
The injection hole interval, injection method (point injection, columnar injection, simultaneous injection of multiple stages or selective injection), unit stage length, and discharge amount per minute are set so as to satisfy the above conditions.

Table 7 (a) shows the relationship between the injection hole interval, one stage length, the discharge amount per minute q (L / min), and the injection time H. 18 and FIG. 19 and Table 7 (a) show that in the present invention, a long injection time with a long discharge time and a long gelling time with a wide injection hole interval is used to reduce the deviation from a predetermined region and to infiltrate into soil particles. Assuming that β = H / GT _S0 including the case of primary injection, the formulation of the injection solution should be set within the range of β = 1080 to 0.001 (0085), more preferably β = 108 to 1. understood.
However, GT ₀ = 10000 minutes to 10 minutes (0085), GT ₀ ≧ H ≧ GTs ₀
As described above, the present invention makes it possible to improve the ground in which it is difficult to deviate to the ground surface or a coarse soil layer under the ground conditions of a complicated soil layer, but the injection liquid deviates outside the predetermined injection region even if the injection hole interval is further increased. Thus, it is possible to form a consolidated body corresponding to a predetermined injection amount without the need.

Specific examples are shown below.
Injection hole interval: 1m to 3m (Table 7 (a))
Soil gelation time (GT _S0 ) = 10-3000 minutes (Figure 21)
Injection speed (discharge rate per minute) = 1 to 30 l / min (Table 7 (a))
However, the injection speed is within the limit penetration injection speed. (Figures 12 and 13)
Injection volume per stage = 132 l to 10,800 l (Table 7 (a))
Injection time per stage (H) = 4.4 minutes to 10,800 minutes (Table 7 (a))
β = H / GT _S0 = 10800 / 10-4.4 / 3000 = 1080-0.001, preferably 1080-1
The above is a case including the point injection.In the case of the multi-point simultaneous injection or the multi-stage simultaneous injection, the injection amount of one stage in Table 7 is divided by the number of the simultaneous stages. Become smaller. Therefore, β also decreases.

Further, from Table 7 (a), if the discharge speed per minute is 1 to 25 L / min limited to the point injection, H = 5.28 to 10,800 minutes, which can be similarly calculated.
If limited to columnar penetration,
Injection volume per stage 132l to 10,800l (Table 7 (a))
Injection speed 10l-30l / min (Table 7 (a))
4.4 minutes to 1080 minutes of injection time per stage (Table 7 (a))
Soil gelation time (GT _S0 ) = 10-3000 minutes (Figure 21)
β = H / GT ₀ = 1080/10 to 4.4 / 3000 = 108 to 0.001, preferably β = 108 to 1.
In the above, it is preferable to set H = GT _S0 when H ≧ G _S0 (FIG. 25) when it is considered that the infusate does not easily deviate from the injection target, and the minimum value of H = H / GT _S0 is 1. Β = 1080-1 when the point injection is included, and β = 108-1 when the column injection is limited.

An injection design consisting of the formulation of the injection solution satisfying the above conditions, the injection hole interval, the unit stage, the injection amount per minute, and the injection time H per stage may be performed. Also, from FIG. 21, in the case of the combined injection of the primary injection and the secondary injection, the gel time in the soil may be generally expected to be about 10 minutes.
A specific example is shown in Table 7 (b).

  INDUSTRIAL APPLICABILITY The present invention is mainly suitable for improving the water stoppage of the ground, increasing the strength, and preventing liquefaction, and can inject a large amount of the injected material into the ground around the hole wall in a wide range and uniformly at a low pressure. INDUSTRIAL APPLICABILITY The present invention has a large consolidation diameter even in an inhomogeneous ground, reduces deviation to a range other than a predetermined range, and can reliably and economically improve the ground.

A… Injection tube device
1… ground
2 ... Drilling
3 ... Seal grout
4 ... Injection outer tube
5… Injection tube
6… Outer tube outlet 2
7 ... Surface discharge section 7 '... Slit
8… Long elastic peritoneum
9… Fixing material, crimping fitting
10… Inner pipe packer
11,11A, 11B… Injection liquid feed line
11 '… Injected liquid feed line check valve
12… Inner pipe outlet
13 ... Injection part of inner tube
14 ... Long elastic coating film
15… Outer pipe discharge port 1 check valve
16… Outer tube outlet 1
17… Outer pipe outlet check valve (elastic sleeve)
18… Packer
19… Discharge port of inner and outer pipe of bag packer
20… Check valve inside bag packer
21… Packer fluid flow path
22 ... Packer fluid discharge port
23… Seal grout splitting
24… space

(Claim 1)
A ground injection method in which a solution-type silica injection liquid is injected into the ground through an injection pipe to improve the ground. See (0108) to (0121) below.
1) Set the silica concentration of the silica injection liquid to obtain the required strength at a predetermined density using the target soil.
2) Using a predetermined silica concentration, prepare a silica injection solution having a gelation time (GT ₀ ) corresponding to the pH or the additive.
3) Mix the silica injection solution with the soil in situ and measure the gelation time (GT _S0 ) in the soil.
4) Set the amount of soil to be consolidated at the unit stage based on the assumed injection hole interval, injection method, and one injection stage length.
5) Set the injection amount based on the amount of soil to be consolidated at the unit stage, and set the injection time (H) per unit stage from the injection speed within the permeation limit.
6) Depending on the ground condition, injection hole interval, and injection amount per unit stage,
Formulation is set up based on the gelation time (GT ₀ ) and silica concentration of the silica injection liquid that satisfies GT ₀ > H ≧ GT _S0 or GT ₀ > GT _S0 ≧ H.

(Claim 2)
In the ground injection method in which the solution-type silica injection liquid is injected into the ground through an injection pipe to improve the ground, the gelation time of the silica injection liquid is GT ₀ , and the gelation time obtained by mixing the injection liquid and the in- situ soil is underground gelation . When the time GT _S0 and the injection time per stage are H, these values are set in the following ranges to reduce the deviation of the silica injection liquid out of the injection range. See (0108) to (0121) below.
(1) The injection speed should be within the limit permeation injection speed.
(2) Injection hole spacing or consolidation diameter L = 1.0-3.0m
(3) Injection rate per minute q = 1 l to 30 l / min, provided that it is within the limit permeation injection rate.
(4) 1 stage length: 0.33m ~ 3.0m
(5) Injection time per stage H: 4.4 minutes to 10,000 minutes However, the injection time (H) can be reduced in consideration of workability at the site and shortening of the latter period.
(6) Gel time of injection solution GT ₀ : 10 minutes to 10,000 minutes (7) pH of injection solution (pH ₀ ): 1 to 10
(8) Silica concentration: 0.4 % to 40% (% by weight)
(9) Soil gelation time GT _S0 : 10 minutes to 3000 minutes Here, within the critical penetration rate refers to a penetration rate lower than the splitting / penetration rate.

(Claims 3 and 4 )
3. The soil injection method according to claim 1 or 2, wherein the solution-type silica injection liquid is injected into the ground to improve the ground. See (0108) to (0121) below.
Injection hole interval: 1m-3m
Soil gel time (GT _S0 ) = 10 minutes to 3000 minutes Injection rate (discharge rate per minute) = 1 l to 30 l / min
However, the injection speed is within the limit penetration injection speed.
Injection volume per stage = 132l to 10,800l
Injection time per stage (H) = 4.4 minutes to 10,800 minutes β = H / GT _S0 = 10800/10 to 4.4 / 3000 = 1080 to 0.001, preferably 1080 to 1

(Claims 5 and 6 )
The ground injection method according to any one of claims 1 to 4 , which is a columnar infiltration injection and satisfies the following conditions. See (0108) to (0121) below.
132l to 10,800l injection volume per stage
Injection speed 10l-30l / min
Injection time 4.4 min ～1080 minutes soil gelation time per stage (GT _S0) = 10 min 3000 min _{β = H / GT 0 = 1080} / 10~4.4 / 3000 = 108~0.001, preferably beta = 108 ~ 1

(Claim 7)
In Claims 1 to 6, the pH of the silica injection solution is 1 to 10, and one or more of colloidal silica or water glass and one or more of an acid or a salt as a reactant. When the silica injection liquid is composed of colloid, water glass and acid, the ratio of the silica concentration caused by the silica colloid to the silica concentration caused by the water glass is 100: 0 to 0: 100, and the silica concentration Is a silica grout selected from a composition of 0.4 % to 40% by weight, a molar ratio of silica of 2.0 to 100, and a gelling time of the injection liquid of 10,000 minutes from instantaneous setting. (Figures 12 and 13)

(Claim 8)
The ground injection method according to claim 1 , wherein the silica injection liquid is injected into the ground by point injection, multi-point injection, columnar injection, multi-point simultaneous injection, or multi-stage simultaneous injection or selective injection. . (Fig. 14, Fig. 15, Table 7)

Table 7 (a) shows the relationship between the injection hole interval, one stage length, the discharge amount per minute q (L / min), and the injection time H. 18 and FIG. 19 and Table 7 (a) show that in the present invention, a long injection time with a long discharge time and a long gelling time with a wide injection hole interval is used to reduce the deviation from a predetermined region and to infiltrate into soil particles. If also the β = H / GT _S0 including the case of primary infusion in, β = 1080~ 0.001, preferably in the al found that may be set formulation of the infusate in the range of beta = 108 to 1 Was.
However, GT ₀ = 10000 minutes to 10 minutes (0085), GT ₀ ≧ H ≧ GTs ₀
As described above, the present invention makes it possible to improve the ground in which it is difficult to deviate to the ground surface or a coarse soil layer under the ground conditions of a complicated soil layer, but the injection liquid deviates outside the predetermined injection region even if the injection hole interval is further increased. Thus, it is possible to form a consolidated body corresponding to a predetermined injection amount without the need.

Further, from Table 7 (a), if the discharge speed per minute is 1 to 25 L / min limited to the point injection, H = 5.28 to 10,800 minutes, which can be similarly calculated.
If limited to columnar penetration,
Injection volume per stage 132l to 10,800l (Table 7 (a))
Injection speed 10l-30l / min (Table 7 (a))
4.4 minutes to 1080 minutes of injection time per stage (Table 7 (a))
Soil gelation time (GT _S0 ) = 10-3000 minutes (Figure 21)
β = H / GT ₀ = 1080/10 to 4.4 / 3000 = 108 to 0.001, preferably β = 108 to 1.
In the above, it is preferable to set H = GT _{S0 in} the case of H ≧ G _S0 (FIG. 25) if it is considered that the infusate is unlikely to deviate from the injection target, and the minimum value of β = H / GT _S0 is 1. Β = 1080-1 when the point injection is included, and β = 108-1 when the column injection is limited.

Claims (13)

In the ground injection method for injecting a solution grout into the ground to improve the ground, the gel time of the injection liquid is GT ₀ , the gel time of the mixture of the injection liquid and the underground gel time GT _S0 , and the injection time per stage is H And the ground injection method that satisfies the following conditions.
1) Set the silica concentration to obtain the required strength at a predetermined density using the target soil.
2) Using a predetermined silica concentration, prepare a silica grout formulation having a gelation time (GT ₀ ) corresponding to the pH or additive.
3) Mix the mixture with the soil at the site and measure the gelation time (GT _S0 ) in the soil.
4) Set the amount of soil to be consolidated at the unit stage based on the assumed injection hole interval, injection method, and one injection stage length.
5) Set the injection amount based on the amount of soil to be consolidated at the unit stage, and set the injection time (H) per unit stage from the injection speed within the permeation limit.
6) Depending on the ground condition, injection hole interval, and injection amount per unit stage,
GT ₀ > H ≧ GTs ₀ or GT ₀ > GT _S0 ≧ H
A formulation is set up that consists of the gel time (GT ₀ ) of the injection solution and the silica concentration. In the ground injection method for injecting a solution grout into the ground to improve the ground, the gel time of the injection liquid is GT ₀ , the gel time of the mixture of the injection liquid and the underground gel time GT _S0 , and the injection time per stage is H And setting these values in the following range to reduce the deviation of the injected material outside the injection range.
(1) The injection speed should be within the limit permeation injection speed.
(2) Injection hole spacing or consolidation diameter L = 1.0 to 3.0 m
(3) Injection rate per minute q = 1 to 30 l / min.
(4) 1 stage length: 0.33m ~ 3.0m
(5) Injection time per stage H 4.4 to 10,000 minutes However, the injection time (H) can be shortened in consideration of workability at the site and shortening of the latter period.
(6) Air gelation time GT ₀ : 10 minutes to 10,000 minutes (7) Air pH (pH ₀ ): 1 to 10
(8) Silica concentration: 0.4 to 40% (% by weight)
(9) Soil gel time GT _S0 : 10 minutes to 3000 minutes Here, within the critical penetration rate refers to a penetration rate lower than the splitting / penetration rate. 3. The ground injection method according to claim 1, wherein the solution-type grout is injected into the ground to improve the ground. 3.
Injection hole spacing 1m-3m
Soil gel time (GT _S0 ) = 10-3000 minutes Injection rate (discharge rate per minute) = 1-30 l / min
However, the injection speed shall be within the limit permeation injection speed.
Injection volume per stage = 132l to 10,800l
Injection time per stage (H) = 4.4 minutes to 10,800 minutes β = H / GT _S0 = 10800/10 to 4.4 / 3000 = 1080 to 0.001, preferably 1080 to 1 The columnar infiltration method according to any one of claims 1 to 3, wherein the ground injection method satisfies the following conditions.
132l to 10,800l injection volume per stage
Injection speed 10l-30l / min
Injection time per stage 4.4 minutes to 1080 minutes Soil gelation time (GT _S0 ) = 10 to 3000 minutes β = H / GT ₀ = 1080/10 to 4.4 / 3000 = 108 to 0.001, preferably β = 108 to 1   In the ground injection method according to any one of claims 1 to 4, after injecting the primary injecting material, prior to injecting the secondary injecting material, water or the injecting material was press-fitted to split the seal grout. In the above, the ground injection method is characterized by injecting at a critical permeation injection speed of the ground.   6. The ground injection method according to claim 5, wherein after the water or the primary injection material is injected, the secondary injection material is subsequently injected at an injection speed within the limit penetration injection speed.   The method according to any one of claims 1 to 6, wherein the injection liquid has a pH of 1 to 10, and contains one or more of silica colloid or water glass and an acid as a reactant. Alternatively, when one or more kinds of salts are used as an active ingredient, and the injection solution is composed of colloid, water glass and acid, the ratio of the silica concentration caused by the silica colloid to the silica concentration caused by water glass is 100: A ground injection method characterized by being a silica grout selected from a composition of 0 to 0: 100, a silica concentration of 0.4 to 40 wt%, a molar ratio of silica of 2.0 to 100, and a gelation time of 10,000 minutes from instantaneous setting.   8. The ground injection method according to claim 7, wherein the injection liquid is injected into the ground by point injection, multipoint injection, columnar injection, multipoint simultaneous injection, multistage simultaneous injection, or selective injection. Injection method.   The ground injection method according to any one of claims 1 to 8, wherein the injection pipe is provided in a seal grout filled in a drill hole, and the seal grout is disposed in the seal grout in the drill hole. A ground injection method characterized by being filled after filling or further swelling a bag packer by injecting a consolidating material into the borehole from the injection pipe.   The soil injection method according to any one of claims 1 to 9, wherein at least one bag body forming a bag packer on an injection pipe tube wall during drilling and a ground on a pipe wall below the bag body. (1) Filling the bag with the curable suspension and inflating it to form a bag packer using an injection pipe device having a discharge port for injecting the injection liquid, and (2) forming a seal grout in the bore hole. In the filling step and (3) the step of breaking the seal grout from the discharge port provided below the bag and injecting the injection liquid into the ground, the seal grout fills the bag with the curable suspension. Or filling the inside of the borehole with the injection pipe or filling the borehole with the seal grout and the filling material in the bag packer continuously from the injection pipe. Injection method.   The ground grouting method according to any one of claims 1 to 10, wherein the seal grout uses a suspendable consolidated material, and the grouting of the drilled wall is performed by injecting the suspended primary grout into the ground. A ground injection method characterized by performing filling without filling.   The ground injection method according to any one of claims 1 to 11, wherein the bag packer provided in the injection pipe is made of a cloth in which a part of the component of the caking suspension is leached from the cloth. Ground injection method characterized by the following.   13. The soil injection method according to claim 12, wherein a part of the component of the solidifying suspension leached from the cloth of the bag packer is leached and solidified, and an underground packer larger than the expanded bag packer is formed. A ground injection method characterized by forming.