KR101542078B1

KR101542078B1 - Soil retaining wall structure and Method for constructinging the same

Info

Publication number: KR101542078B1
Application number: KR1020140116937A
Authority: KR
Inventors: 황운식
Original assignee: 유구이앤씨(주); 황운식
Priority date: 2014-09-03
Filing date: 2014-09-03
Publication date: 2015-08-06
Also published as: JP6481840B2; WO2016036080A2; SG11201701234WA; JP2017530274A; WO2016036080A3

Abstract

The present invention relates to a construction method of an environmentally friendly retaining wall, and a retaining wall manufactured thereof. According to the present invention, the construction method of the retaining wall comprises: (a) a steel installation step of excavating the ground along a border line of an area where a building is to be built to form a plurality of drilling holes to be spaced from each other, and inserting a steel material into the drilling hole; (b) a wall forming step of forming a continuous cement wall on a rear side of the area where the steel material is disposed, and injecting a cement stabilizer in one process among the drawing processes after an excavation equipment is inserted into the ground by a planned depth to be mixed with the soil of the excavated ground in order to enable the cement stabilizer to be hardened to form the continuous cement wall; and (c) a wale installation step of installing a wale mutually connecting the steel materials.

Description

Soil retaining wall structure and method for constructing same

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to an earth retaining wall or a water wall, which is installed on a excavation surface in order to prevent collapsing of excavated ground or inflow of ground water for foundation construction of a building structure, and a construction method for making the earth retaining wall.

In order to perform the foundation work of the building structure, the ground is excavated. In order to prevent the excavation surface from collapsing, it is common to install the earth retaining wall. The retaining wall also serves as a water wall to prevent groundwater from entering.

The structure of the earth retaining wall has been developed in various forms from the past, and various construction methods have been proposed according to the structure of the earth retaining wall. For example, a method of using a sheet pile is presented. However, the sheet pile can be applied to weathered rocks that have been subjected to soil and weathering for a long period of time, but they can not be applied to soft rocks or light rocks. In order to solve such a problem, as shown in FIG. 1, a method of inserting an H-shaped file up to a rock layer first and then installing a sheet file on the back side has been used. The sheet file method is described in more detail. The H-shaped file is integrally formed by hanging a wale on the front surface of the H-shaped file. Although not shown in the drawings, a strut and an anchor for interconnecting wale- do.

Recently, a method of using a cement wall (soot cement or concrete wall) instead of a sheet file has been used. In the method using the cement wall, a perforation hole is formed up to the rock layer using an auger screw. Perforated holes are formed continuously along the boundary of the area where foundation work is required. After the cement (grout material) is injected into the perforation hole and the cement is cured after inserting the H-shaped pile, a continuous cement wall containing the H-shaped pile is formed. This cement continuous wall performs retaining and order functions.

However, the conventional method shows limited applicability in retaining walls and columns, and as a hypothetical case, when the structure is to be removed at the completion of foundation work, the weakness is exposed.

In other words, the conventional method is limited to the soft clay layer, and it is difficult to apply the method to segregation and leaching of the material in the soil, the river near the river, and the coast where the permeability coefficient is high. It is difficult to secure durability (strength and degree). In addition, since the H-shaped file is manufactured at a predetermined height as an off-the-shelf product, a plurality of H-shaped files must be connected in series when the hole is deep. However, since a separate steel material is added to the outer surface of the H-shaped file in order to interconnect the H-shaped files, the middle portion of the H-shaped file is formed so as to protrude as a whole. This protruding portion acts as a jaw, making it difficult to draw out the H-shaped pile from the subsequently cured cement wall. There is no problem if the earth retaining wall is installed as a permanent facility, but as a hypothetical case, there arises a problem that demolition is not easy in case of demolishing in the future. This makes it difficult to reuse H-type files.

On the other hand, environmental problems are another issue when using existing cement. Cement is strongly alkaline and often contains heavy metals, and cement meets with groundwater and releases harmful components. Hazardous ingredients affect the surrounding water and ecosystem as they move along the groundwater, and measures are needed.

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the above-mentioned problems, and has an object of providing a steel sheet having a wide range of applicability regardless of the soil and having improved durability such as strength, water- It is an object of the present invention to provide an environment-friendly earth retaining wall and a method of constructing the earth retaining wall which are advantageous for heavy metal contamination and pollution prevention by renewing the composition of the grout material.

According to another aspect of the present invention, there is provided a method of constructing a retaining wall, comprising: drilling a ground along a boundary line of an area where a building is to be constructed to form a plurality of perforations spaced apart from each other; step; (b) forming a cement continuous wall behind the region in which the steel material is disposed, injecting the cement stabilizer into the soil at a depth of the design depth, Forming a cement continuous wall by curing the cementitious material; And (c) a welt installation step of installing a welt that interconnects the steel materials.

In the present invention, when the cement stabilizer and the gypsum are mixed, a heavy metal adsorbent is injected together with the cement stabilizer. When mixing the cement stabilizer and the gypsum, compressed air is injected, and the heavy metal adsorbent is injected by the compressed air.

Particularly, the heavy metal adsorbent is prepared by adding a plurality of monomers having one to three acid functional groups to a resin obtained by copolymerizing a plurality of alkyl methacrylates containing C4 to C8 carbon and 2-dimethylaminoethyl methacrylate to obtain 2 The polymer material formed by the emulsion polymerization reaction is mixed with a chelating resin containing a carboxyl metal group.

Meanwhile, an embodiment of the present invention may include a process of grooving between a wale band and a cement continuous wall. The groove filling process includes a connecting part connected to the wale band on the entire upper surface of the upper part, a rear part of which is inclined so that the lower part has a larger cross-sectional area than the upper part, Wherein the front surface of the first block is inclined with respect to the inclination of the rear surface of the first block so that the upper portion has a wider cross section than that of the lower portion and the back surface is formed corresponding to the outer shape of the cement continuous wall, And the second block is inserted between the first block and the cement continuous wall.

When the interval between the wale band and the cement continuous wall is wide, both the front surface and the back surface are formed between the first block and the second block so as to correspond to the inclination of the back surface of the first block, At least one connection block may be provided.

Also, in the present invention, a variety of fillers such as concrete, steel, wood, and plastic may be used for the groove filling process. In the present invention, a unique structure of the support can be used when performing the grooving through concrete spotting. That is, the support base includes a mounting portion detachably installed on the wale band, and a support bar hingably coupled to the mounting portion and disposed horizontally below the space between the wale band and the cement continuous wall when rotated in one direction have.

In order to improve the durability of the cement wall, a reinforcing material such as carbon fiber, steel fiber, and geotextile can be mixed and used.

The present invention provides a earth retaining wall having a structure capable of reliably holding a earth pressure acting on an excavation surface, and a method of constructing the earth retaining wall.

In addition, the present invention provides a retaining wall which can be easily removed and reused, and a construction method thereof. Specifically, the H-shaped file is separately installed without being inserted into the cement continuous wall, and this advantage is manifested by using a plurality of blocks as the filler.

Also, in the present invention, heavy metal adsorbent is used together with cement stabilizer as a material for forming a cement continuous wall, thereby causing no environmental problems such as disturbance of surrounding water and ecosystem due to leaching of heavy metal according to groundwater inflow, There is an advantage that the generated slime can be recycled.

In addition, the present invention is advantageous in that it can be applied in a place where it is difficult to construct, for example, in a river side or a coastal area where the coefficient of permeability is high, and has wide applicability and durability. Particularly, the earth retaining wall according to the present invention has salt resistance property due to the characteristics of the cement stabilizer, and thus it has an effect of preventing the salting when applied to the coast.

1 is a schematic perspective view for explaining a conventional method of constructing an earth retaining wall.
2 is a schematic flow chart of a method of constructing an earth retaining wall according to an embodiment of the present invention.
3 is a schematic perspective view of the earth retaining wall made by the construction method shown in FIG.
FIGS. 4 and 5 illustrate two methods for performing the wall forming step. FIG. 4 is a view for explaining a penetration spraying method, and FIG. 5 is a view for explaining a drawing spraying method.
6 is a schematic view of a heavy metal adsorbent injection tube.
7 is a schematic perspective view of a first block, a second block, and a connection block used in the present invention.
Figs. 8 and 9 show the states when the blocks are grooved between the wale band and the cement continuous wall. Fig. 8 is a line aa in Fig. 7, and Fig. 9 is a sectional view taken along the line bb in Fig.
10 is a schematic perspective view showing the structure of a support used in an embodiment of the present invention.
11 is a schematic cross-sectional view of the cc line in Fig.
12 is a table showing the criteria for testing a mixture of a cement stabilizer and a heavy metal adsorbent used in the present invention.
Fig. 13 is a mixture chart of a mixture sample and a comparative sample in which a cement stabilizer and a heavy metal adsorbent are mixed in the present invention.
FIG. 14 and FIG. 15 are experimental results using the formulation table of FIG. 13, FIG. 14 is a table showing the results, and FIG. 15 is a photograph showing the rate of volume change.
Fig. 16 is a table showing the mixture of the cement stabilizer, the heavy metal adsorbent and the gypsum used in the present invention and the comparative sample.
17 and 18 are experimental results using the formulation table of FIG. 16. FIG. 17 is a table showing the results, and FIG. 18 is a photograph showing the rate of volume change.
FIG. 19 is a photograph showing the result of water-jet separation test for a cement stabilizer to which a heavy metal adsorbent is added according to the present invention.

The method of constructing the earth retaining wall according to the present invention has two advantages.

The first advantage is attributed to the fact that the retaining walls are hypothetical. In other words, it is necessary to dismantle the temporary retaining wall after the construction such as the foundation work is performed. In this construction method, there is an advantage that the material such as the H type pile and the fill material can be easily separated. In the conventional construction method, a method of installing a steel material inside a cement wall is adopted. However, in the present invention, this advantage is obtained in that a steel material and a cement wall are separated from each other and a prefabricated filler material is used.

A second advantage is that the present invention is environmentally friendly. When the cement continuous wall is used in the method of constructing the earth retaining wall, there is a problem that the surrounding water system and the ecosystem are disturbed due to the harmful components in the cement. In the present invention, by using the unique and environmentally friendly cement, , It is possible to reinforce the rigidity of the cement continuous wall.

The first advantage of the above advantages is that the ease of construction and demolition is due to the structural aspect of the retaining wall. First, the structure and construction method of the retaining wall are explained. The second advantage is the structural stiffness of the cement continuous wall The environmental friendliness is due to the material properties of the cement, which will be described later.

The method of constructing the earth retaining wall according to one embodiment of the present invention and the structure of the earth retaining wall made by this construction method will be described with reference to the accompanying drawings.

FIG. 2 is a schematic flow chart of a method of constructing an earth retaining wall according to an embodiment of the present invention, and FIG. 3 is a schematic perspective view of a earth retaining wall made by the construction method shown in FIG.

Referring to FIGS. 2 and 3, the method of constructing the earth retaining wall according to an exemplary embodiment of the present invention includes a steel installation step M10, a wall forming step M20, and a wale installation step M30.

In the steel installation step M10, the ground is excavated at regular intervals to form a plurality of perforation holes h in the same manner as the conventional method of constructing the earth retaining wall. For example, a perforation hole h is formed at regular intervals along a boundary line of a square area having a length of 30 m and a length of 30 m. Then, a steel material such as an H-shaped pile 10 is inserted into the hole h. The depth at which the H-shaped pile 10 is inserted extends to the rock layer r through the soil layer. When the steel is inserted into the rock layer, the bearing capacity against the surrounding earth pressure can be increased. However, depending on the ground conditions and construction conditions, steel may be applied only to the soil layer. When the depth of the perforation hole (h) is deep, a plurality of steel materials can be connected and installed. Since the steel is manufactured to a certain standard as a ready-made product, it is necessary to connect a plurality of steel materials. Taking the H-shaped file as an example, two steel materials are arranged in series, and the outer surfaces of the two steel materials are covered with a connecting plate (not shown).

In the past, H type files were inserted before the cement was cemented with multiple H type files. When the cement is cured and the H type file is taken out from the cement continuous wall at the completion of the foundation work, It is very difficult to take out the H-shaped file by acting as a latching jaw.

However, the present invention solves the above-mentioned problem by separately installing the H-shaped file in the cement wall instead of inserting the H-shaped file into the cement wall. However, if the cement wall and H-file are separately constructed, the construction may become more complicated. However, such disadvantages are compensated for by increasing the stiffness of the earth retaining walls and the bearing capacity by adopting the construction method of the present invention. The most basic and important function of earth retaining walls is resistance to earth pressure. If the H-shaped file and the cement wall are provided in the same manner as in the present invention, there is an advantage that the resistance against earth pressure is improved.

As described above, after the steel material such as the H-shaped file 10 is installed, the wall forming step M20 is performed. The wall 20 is continuously formed on the rear side of the H-shaped pile 10 to prevent the groundwater from flowing into the area where foundation work is performed and to withstand the earth pressure.

In the wall forming step (M20), excavation and mixing equipment such as Auger screw is used. A rod auger screw s is shown in Fig. The auger screw (s) has various shapes according to the number of axes from one axis to four axes, and in the present invention, the auger screw can be selected according to the condition of the wall. The axes of the auger screw (s) are able to penetrate the ground while rotating. In addition, the shaft is formed in a hollow shape. When the cement stabilizer and heavy metal adsorbent are supplied through the shaft, the cement stabilizer is injected into the ground through the lower end of the shaft. In each axis, a plurality of blades are formed in the lateral direction so that the cement stabilizer and excavated soil can be agitated with each other.

More specifically, the wall forming step M20 is performed in the order of intrusion, mixing, drawing, and curing. As shown from the first to the third figure in Fig. 4, the auger (s) penetrates the ground (g) to the design depth. When the Auger screw (s) is penetrated to the design depth, the Auger screw is pulled out.

The mixing depends on the intrusion-type ejection or ejection-ejection type. That is, as shown in FIG. 4, when the intrusion-blowing type is adopted, the cement stabilizer and the heavy metal adsorbent are injected together and mixed in the process of penetrating the auger screw (s) into the ground. However, as shown in FIG. 5, when the pull-out method is adopted, the cement stabilizer is injected while drawing the auger screw (s) and mixed with the gravel. Of course, both cement stabilizer and heavy metal adsorbent can be injected during the penetration and drawing process to stir the excavated soil

In the present invention, a heavy metal adsorbent is supplied together with a cement stabilizer to form a cement wall body 20. The cement stabilizer is introduced into the inner injection path of the auger screw shaft by a supply pipe (not shown). In the case of heavy metal adsorbent, the cement stabilizer is transferred to the inner injection path of the auger screw shaft through a separate injection pipe as shown in FIG. Particularly, in the present invention, an air supply pipe capable of supplying high-pressure compressed air to the injection pipe for supplying the heavy metal adsorbent is attached.

A heavy metal adsorbent is fed into the injection tube and blows high pressure compressed air so that the heavy metal adsorbent is entrained into the inside (upper end or lower end) of the rod (shaft) by compressed air. In particular, in this embodiment, the heavy metal adsorbent injection pipe is connected to the lower end of the rod, and the compressed air is ejected at a pressure of 5 to 15 kgf / cm ² . The heavy metal adsorbent injection pipe is provided with a check valve to prevent the heavy metal adsorbent from flowing backward.

The heavy metal adsorbent, the cement stabilizer and the excavated soil are stirred together in the ground to form a slime. The compressed air provides an air bubble to improve the mixing performance of the cement stabilizer, heavy metal adsorbent and excavated soil.

In one embodiment of the present invention, reinforcing fibers such as carbon fiber or steel fiber are mixed with the cement stabilizer to improve the strength (particularly tensile strength) of the cement wall to reduce cracks.

When the drawing of the auger screw is completed, the slurry is mixed with the cement stabilizer and soil. In this state, the slime cures when a certain period of time is elapsed to form the cement continuous wall body 20.

As described above, after reinforcing the ground by forming the steel material 10 and the cement continuous wall 20 along the boundary of the area where the structure is to be built, the inside of the boundary area, that is, the area surrounded by the cement continuous wall 20 Excavation. When the inside of the boundary area is excavated, one side of the H-shaped file 10 and the cement continuous wall 20 is exposed to the outside, as shown in Fig. Then, in the process of downwardly digging down the inside of the boundary region, a wale installation step M30 is performed in which a wale band 30 is installed on the front side of the H-shaped files 10. The wale band 30 horizontally arranges the H-shaped steel material so that the H-shaped piles 10 installed vertically are constrained to be integrally formed. The plurality of H-shaped piles (10) by the wale can withstand the earth pressure of the excavation section by acting as one whole. Further, a strut (not shown) or a jack (not shown) for interconnecting the wales installed on the excavation face facing each other can be installed.

As described above, after the main structure of the earth retaining wall is completed, the grooving step M40 is performed. The groove filling is to fill the space between the wale 30 and the cement continuous wall 20 with a filling material to reinforce the bearing capacity and rigidity of the earth retaining wall.

In an embodiment of the present invention, the block is used as a filling material to facilitate the installation and removal of the earth retaining wall. The blocks used in the present invention are shown in Figs. FIG. 7 is a schematic perspective view of a first block, a second block and a connecting block used in the present invention, and FIGS. 8 and 9 show states when the blocks are slotted between a wale band and a cement continuous wall, 8 is aa line in Fig. 7, and Fig. 9 is a sectional view taken along the line bb in Fig.

Referring to FIGS. 7 to 9, the first block 41 is a portion supported by the wristband 30 and is formed in the shape of a hexahedron as a whole. More specifically, the front surface 411 facing the wristband 30 is formed vertically in the first block 41, but the back surface 412 facing the cement continuous wall body 20 is formed obliquely, Is formed to be narrower than the lower portion.

In the upper portion of the first block 41, a hooking portion 413 is provided which can be inserted on one side 31 of the H-shaped file used as a welt. The width of the insertion groove 414 of the hook portion 413 is substantially equal to the thickness of the wristband 30 so that the first block 41 can be vertically arranged and stably supported on the wristband 30.

The second block 42 is interposed between the first block 41 and the cement continuous wall 20 so that the first block 41 and the second block 42 are connected to the wale 30 and the cement continuous wall 20 ) Is filled. However, if the interval between the wale 30 and the cement continuous wall 20 is wide, as shown in Fig. 7, a connecting block 43 is provided between the first block 41 and the second block 42 It may be intervening.

The front surface 421 of the second block 42 is curved so as to correspond to the outer surface shape of the cement continuous wall 20 and the back surface 422 is formed on the front surface of the first block 41 or on the front surface of the connecting block 43, (I.e., a case where the light emitting diode is interposed). Accordingly, the second block 42 is formed so that the cross-sectional area of the upper portion is larger than that of the lower portion, as opposed to the first block 41.

The front surface 431 of the connection block 43 is in close contact with the first block 41 and the rear surface 432 is in close contact with the second block 42. The front surface 431 and the rear surface 432 of the connecting block 43 are both inclined.

When the first block 41 and the second block 42 are filled with the space between the wale 30 and the cement continuous wall 20 without the connecting block 43, When the second block 42 is inserted between the first block 41 and the cement continuous wall 20 in a state in which the first block 41 is hooked on and supported by the first block 41, And the second block 41 is not detached downward because it is supported on the back surface 412.

The same applies to the case where the connecting block 43 is interposed. The connecting block 43 and the second block 42 are also supported on the inclined rear surface so that the connecting block 43 and the second block 42 are separated downward And can be installed between the wale band 30 and the cement continuous wall 20.

Here, the important point is the angle of the inclined surface formed in the block. The slower the angle of the slope, the better the blocks can be supported. However, if the inclination is gentle, the basic function of the grooved material for transmitting the earth pressure acting on the cement continuous wall 20 to the H-shaped pile 10 integrated by the wale band 30 can be neglected. That is, the earth pressure on the excavation surface acts in the horizontal direction. Since the second block 42 or the connection block 43 is supported on the inclined surface, the earth pressure can not be fully transmitted to the wale 30, Rather, the second block 42 or the connecting block 43 may be deviated upwardly along the inclined surface due to the earth pressure.

That is, the inclined surface of the block should be formed gently in terms of preventing the block from being detached downward, but it has a kind of inconsistency that must be formed abruptly in order to be faithful to the basic function as the filler material. In order to solve both of these functions, the present invention forms an inclined surface in a range of about 70 to 90 degrees.

In addition, although the blocks can be stably supported even if the inclination is formed in the above-mentioned range, in order to further improve the support force between the blocks, the support portion and the fitting portion are formed at the lower portion of the blocks in the embodiment of the present invention.

The main block 415 is formed on the lower portion of the first block 41 so as to protrude from the rear surface 412 and the main block 415 is provided below the front surface 421 of the second block 42. Accordingly, A main fitting portion 423 is formed concavely so that the main fitting portion 423 can be inserted. The second block 42 can be more stably supported by the first block 41 by fitting the main receiving portion 415 into the main fitting portion 423. [

The same is true when the connecting block 43 is interposed. In the example where the connection block 43 is interposed, a fitting portion 433 for fitting the main support portion 415 of the first block 41 is formed on the front surface 431 of the connection block 43, The back 432 of the block 43 may be formed with a receiving portion 434 inserted into the main fitting portion 423 of the second block 42. [ Also, even when a plurality of connecting blocks are interposed, the receiving portion and the fitting portion may be provided in the connecting blocks, and the first and second blocks may be continuously filled with the connecting block.

The configuration of the receiving portion and the fitting portion as described above is for making a stable supporting structure between the first block and the second block or between the first block, the connecting block and the second block. This support structure can be equally applied between adjacent first blocks, between second blocks, and between connection blocks. That is, when carrying out the groove filling in the present invention, the first blocks are continuously arranged along the longitudinal direction of the band, and likewise, the second blocks are arranged continuously. Accordingly, auxiliary supporting portions 416, 424, and 435 are formed at the bottom of the blocks to protrude from one side surface. Corresponding to the auxiliary supporting portions 416, 424, 435, the auxiliary fitting portions 417, 425, 436 are concavely formed on the other side of the blocks. The auxiliary supporting part and the auxiliary fitting part stabilize the mutually supporting blocks mutually adjacent along the longitudinal direction.

Up to this point, we have discussed how to use blocks when performing homing. In the present invention, the filling method is not limited to the use of the blocks, and a method of installing a filling material such as cement or concrete may be employed as in the conventional method. However, the present invention is characterized in that a unique support structure as shown in Fig. 10 is used for the convenience of construction even when a filling material is laid.

Fig. 10 is a schematic perspective view showing the configuration of a support used in an embodiment of the present invention, and Fig. 11 is a schematic cross-sectional view taken along line c-c of Fig.

Referring to Fig. 10, the support base 50 has a mounting portion 51 disposed along a vertical direction. At the upper portion of the mounting portion 51, a hooking portion 511 is formed which can be hooked to the side plate 32 of the wristband 30. [ The support portion 50 can be easily installed and separated in the wale 30 because the hook portion 511 is simply attached to the side plate 32 of the wale 30. In addition, a brace 52 is coupled to the hook portion 511. The braces 52 are arranged in the horizontal direction and are provided between the hooks 511 and one side 31 of the band.

The brace 52 is made of a stretchable structure which can be reduced in length. For example, as shown in FIGS. 10 and 11, the brace 52 includes a hollow fixed base 521 and a movable base 522 that can be introduced and withdrawn into and out of the fixed base 521. The movable base 522 is supported by a spring 53 or a screw. The compressed spring 53 presses the hook portion 511 toward the side plate 32 of the wristband 30 by the elastic restoring force. Therefore, the mounting portion 51 can be brought into close contact with the side plate 32 of the wristband 30 to be more stably supported.

A support bar 54 is hingably coupled to the mounting portion 51 by a pivot pin 541. The supporting bar 54 is horizontally disposed under the wale 30 and the cement continuous wall 20 at the time of rotation to one side. In order to fix the support bar 54, one end is coupled to the support bar 54 and the other end has a link 55 to be coupled to the mount 54. Particularly, since the connecting rod 55 is detachably connected to the mounting portion 54 by a screw 551 or a bolt, the screw 551 can be removed when the supporting bar 54 is rotated. The connecting rod 55 is also made of a fixing base (not shown), a moving base (not shown) and a spring (not shown) in the same manner as the bracing 52 described above, and the connecting rod 55 elastically presses the supporting bar 54 can do. That is, it is possible to assist the support bar 54 to be horizontally disposed in the lower space between the wale 30 and the cement continuous wall 20.

After a plurality of supports 50 having the above-described structure are simply mounted on the wale 30, a support plate is provided on a plurality of support bases 50, a plastic is applied, . In addition, wire meshes and reinforcements can be used in parallel when necessary in the field installation. Conventionally, a lot of time and efforts are required to install and separate the formwork in each district. However, in the present invention, the support stand 50 can be installed and removed very simply, Can be easily carried out.

As described above, according to the present invention, since the H-shaped file is separately installed without being installed in the cement continuous wall, it is not only easy to separate and reuse the H-shaped file later, but also the H- Since the excavation surface is supported, the excavation surface can be effectively prevented from collapsing due to the earth pressure. In addition, in the present invention, the use of a block or a support enables the homemade process to be carried out very simply. Particularly, when the block is used, the homemade material can be easily removed at the completion of the construction.

Hereinafter, a cement continuous wall which serves as another advantage of the present invention will be described. The present invention is characterized in that a cement stabilizer and a heavy metal adsorbent having a unique composition are used as the material of the cement continuous wall for increasing the environment friendliness and strength.

In the present invention, the cement stabilizer is mixed in the range of 15 to 35 parts by weight based on 100 parts by weight of the excavated soil, and the heavy metal adsorbent is mixed in the range of 0.01 to 10 parts by weight based on 100 parts by weight of the cement stabilizer. And water is mixed in the range of 50 to 200 parts by weight when the weight of the total powder is taken as 100. [

The cement stabilizer may be composed of cement alone or may optionally include a pozzolanic mixed material, a tributary admixture and a shrinkage reducing material. In this embodiment, a form including a wettable admixture and a shrinkage reducing agent is used.

The cement may be any one of Portland cement, slag cement and pozzolan cement, or a mixture thereof. Fly ash or slag powder can be added as a mixed material to improve the pozzolanic reaction of cement. When all of the fly ash slag powder is used, the cement is blended in a proportion of 40 to 80% by weight of the total powder, the fly ash in an amount of 5 to 20% by weight of the total powder, and the slag powder in a proportion of 10 to 40% . The mixed material for improving the pozzolanic reaction has the effect of reducing the specific gravity of the cementitious material so as to fill and reinforce the large volume cavity with the same weight and to reduce the bleeding of the cementitious material in the uncured state. It has the effect of improving chemical resistance and durability and increasing long-term strength.

The quick-setting admixture may be calcium aluminate powder, calcium sulphoaluminate powder, alumina cement, or the like, which is produced using bauxite as a raw material.

Cement reacts with water to hydrate to form calcium silicate hydrate (CSH) and calcium hydroxide (Ca (OH) ₂ ) hydrate. When calcium salt such as calcium aluminate or calcium sulfur aluminate is mixed with sulfate powder, Ettringite (3CaOAl ₂ O ₃ 3CaSO ₄ 32H ₂ O) is abruptly formed. Etrinsite improves the reaction with heavy metal adsorbents to reduce volume changes in the mixture, increase viscosity and prevent the generation of bleeding water.

In the present embodiment, the mixing amount of the feedable admixture is 1 to 10% by weight of the total amount of the powder. It is preferable that the amount of the additive admixture increases proportionally as the water powder ratio of the cement stabilizer increases. This is because the quick-setting admixture exhibits an effect of reducing the free water of the grout material (cement stabilizer + water) by bonding with water in a large amount during the process of forming the ettringite.

In the present embodiment, a shrinkage reducing material is added to the cement stabilizer. As the shrinkage reducing material in this embodiment, any one of α-type hemihydrate gypsum (CaSO ₄ · 1 / 2H ₂ O type α) and anhydrous gypsum (CaSO ₄ ) or a mixture thereof is used. The α-type semi-gypsum and anhydrous gypsum have a powder range of 200 to 600 m ² / kg And the mixing amount is 0.5 to 5% by weight of the total powder amount.

In the present invention, heavy metal adsorbent is injected together with a cement stabilizer to adsorb and immobilize heavy metals (Cr ⁶⁺ , Pb, Cd and Hg) generated from the cement to prevent the heavy metal from leaching out from the cement stabilizer do.

In addition, heavy metal adsorbents are supplied with the cement stabilizer to increase the viscosity of the mixture, thereby preventing the mixture from being lost by the groundwater, and inducing no change in the volume of the mixture.

As described above, the application of the air bubbled heavy metal adsorbent improves the mixing performance between the excavated soil and the cement stabilizer, and weakens the adhesion between the cement stabilizer and the excavated soil, thereby facilitating excavation and drawing of the auger do. This method will be very useful for overcoming the limitation that is applied only to the coast where the sand is mainly composed, not the general soil, by forming the pile by stirring the cement stabilizer and the soil.

The heavy metal adsorbent used in the present invention is a resin in which two or more alkyl methacrylates containing C4 to C8 carbon and 2-dimethylaminoethyl methacrylate as main components are copolymerized with one to three acid functional groups The polymer is prepared by a secondary emulsion polymerization (reaction at 80 ° C for 8 hours) with two or more monomers having a carboxyl group, and then mixed with a chelating resin containing a carboxyl methyl group and other chelating resins. The monomer may be at least two of butyl acrylate, stadiene, ethyl acrylate, methyl methacrylate, acrylic acid, and methacrylic acid.

This heavy metal adsorbent can be prepared as a liquid or powder, has a property of adsorbing heavy metals such as Cr ^6+, and shows a strong thickening effect on a liquid phase having an alkali component.

In the present invention, since the heavy metal adsorbent is used to prevent the heavy metal from leaching out from the cement stabilizer, the slime discharged from the construction process (soil + cement stabilizer + heavy metal adsorbent) can be utilized as a landfill. For example, road construction around the construction site can be recycled as the soil that forms the frostbite layer.

Hereinafter, performance tests on the cement stabilizer and heavy metal adsorbent used in the present invention were performed. The experimental criteria were applied to the criteria shown in the table of FIG.

In the table of FIG. 13, the compounding ratios of Examples 1 to 4 in which the compounding ratio of the cement stabilizer and the heavy metal adsorbent used in the present invention are different are shown, and the compounding ratios are shown for two examples using only general cement.

Experiments were conducted on the mixture of the cement stabilizer and the heavy metal adsorbent used in the present invention. In this experiment, the soil was not mixed and the mixing ratios were mixed according to the table in Fig. The results are shown in the table of Fig. 14 and the photograph of Fig.

First, referring to the photograph of FIG. 15, it can be seen that a significant difference occurs in the amount of shrinkage when cement stabilizers added with a heavy metal adsorbent are used in the case of using general cement (left side) and according to the present invention. Referring to the table of FIG. 14, the volumetric change rates of Comparative Examples 1 and 2 were 55% and 38%, respectively, whereas in Examples 1 to 4 of the present invention, the volumetric change was almost 2%.

14, when the heavy metal adsorbent is not used in Comparative Examples 1 and 2 as described above, the bleeding rate (the same as the rate of volume change) is very large, and the elution amount of Cr ⁶⁺ Was 8.6 ppm and 8.8 ppm, respectively, and turbidity was high. On the other hand, in Examples 1 to 4 using a heavy metal adsorbent, the turbidity was very low and no Cr ⁶⁺ was detected.

In Comparative Examples 1 and 2, the volume shrinkage was too large and the sample for strength could not be formed. In Examples 1 to 4, however, the volume shrinkage was very small and the strength sample could be formed. In all cases, similar results were obtained.

Meanwhile, the mixture of the cement stabilizer and the heavy metal adsorbent used in the present invention was mixed with gypsum to conduct experiments. In the table of Fig. 16, the compounding ratio shown in Fig. 13 is shown in the form mixed with excavated soil.

In this experiment, in the form of mixed soil, the blending ratio of each material was blended according to the table of FIG. The results are shown in the table of Fig. 17 and the photograph of Fig.

First, referring to the photograph of FIG. 18, it can be seen that the difference in shrinkage occurs when the cement stabilizer added with a heavy metal adsorbent is used according to the present invention (left side) using general cement. Compared with the untreated mixed soil, the rate of volume change was smaller when using ordinary cement than the untreated mixed soil. However, the rate of volume change was higher than that of the present invention using heavy metal adsorbent.

Referring to the table of FIG. 17, the volume change rates of Comparative Examples 1 and 2 were 9% and 5%, respectively, whereas Examples 1 to 4 of the present invention showed no volume change.

Elution of hexavalent chromium was confirmed at the concentration of 2.6 and 1.05 ppm in the comparative example but not in the example according to the present invention. The turbidity was also high in the comparative example, but it was confirmed that the turbidity was low in the embodiment according to the present invention. Compression strength was comparable to that of the comparative example.

Meanwhile, FIG. 19 is a photograph showing the result of water-jet separation test for the cement stabilizer (right side) and general cement (left side) used in the present invention. The general cement stabilizer has a very high fluidity so that it is instantly loosened when it is added to water to pollute the surroundings and lose its character as a stabilizer. However, in the case of a cement stabilizer added with a heavy metal adsorbent used in the present invention, . That is, the cement stabilizer used in the present invention does not contaminate the surrounding environment and shows that the durability and water repellency can be maintained as the cement stabilizer is cured.

As shown in the above experiments, in the present invention, heavy metal adsorbent mixed with cement stabilizer hardly causes heavy metal leaching, and since the fluidity of the cement stabilizer itself is small, there is no possibility of leakage along the groundwater around the cement stabilizer. And no contamination by the water was found.

In addition, by pressurizing the heavy metal adsorbent with compressed air, bubbles are mixed in the mixture to increase the mixing ratio of the cement stabilizer, the heavy metal adsorbent and the gypsum, and the adhesive force of the mixture becomes small, thereby facilitating the penetration and drawing of the auger.

In addition, after the completion of the construction, the viscosity of the mixed soil is increased, and the mixture is not lost by the ground water or the volume is not reduced, which is advantageous in that durability and strength are guaranteed.

INDUSTRIAL APPLICABILITY As described above, in the present invention, by using a heavy metal adsorbent together with a cement stabilizer as a material for forming a cement continuous wall, the heavy metal is fixed and does not leak to the outside, adversely affecting the environment and the stiffness of the cement continuous wall is also increased There is an advantage.

In the present invention, the terms cement, mortar, and concrete are used together, including cement itself, mortar mixed with cement and sand, or concrete containing a coarse aggregate in mortar. Or mixing soil and aggregate (coarse aggregate and / or fine aggregate) with cement when mixing cement with excavated soil in the field. For example, in the context of the present invention, the term cement refers to a mixture of cement and soil, or a mixture of cement, sand, and soil (which may include aggregate).

In the meantime, although the reference numeral 53 is represented by a spring in the present invention, the length can be adjusted in such a manner that the screw is loosened in addition to the spring. This is equally applicable to the linkage indicated by reference numeral 55.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation and that those skilled in the art will recognize that various modifications and equivalent arrangements may be made therein. It will be possible. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

10 ... H-shaped file (steel) 20 ... cement continuous wall
30 ... wale 41 ... first block
42 ... second block 43 ... connection block
50 ... support

Claims

(a) a steel material installation step of excavating the ground along the boundary line of the area where the building is to be constructed, forming a plurality of perforation holes so as to be spaced apart from each other, and penetrating the perforation hole with the steel material;
(b) forming a cement continuous wall behind the region in which the steel material is disposed, injecting the cement stabilizer into the soil at a depth of the design depth, Forming a cement continuous wall by curing the cementitious material; And
(c) a welt installation step of installing a welt for interconnecting the steel materials,
When the cement stabilizer and the gypsum are mixed, a heavy metal adsorbent is injected together with the cement stabilizer,
The heavy metal adsorbent may be,
A plurality of monomers having one to three acid functional groups are added to a resin obtained by copolymerizing a plurality of alkyl methacrylates containing C4 to C8 carbon atoms and 2-dimethylaminoethyl methacrylate to form a second emulsion polymerization reaction Wherein the polymer material is a mixture of a polymer material and a chelating resin containing a carboxyl metal group.

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The method according to claim 1,
Wherein the compressed air is injected when the cement stabilizer and the gypsum are mixed, and the heavy metal adsorbent is injected by the compressed air.

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The method according to claim 1,
The cement stabilizer is compounded in a range of 15 to 35 parts by weight based on 100 parts by weight of the excavated soil,
Wherein the heavy metal adsorbent is compounded in a range of 0.01 to 10 parts by weight based on 100 parts by weight of the cement stabilizer.

The method according to claim 1,
Wherein the cement stabilizer further comprises a reinforcing material including at least one of carbon fiber, steel fiber, and geosynthetic fiber.

The method according to claim 1,
A first block provided in a space between a back surface of the belt and a front surface of the cement continuous wall is formed with a connecting portion which can be connected to the wale band on the entire upper surface of the upper portion, In addition,
And a second block formed to correspond to an outer surface shape of the cement continuous wall and being in close contact with the cement continuous wall, wherein the second block is formed to have an inclined front surface corresponding to the inclination of the back surface of the first block, Inserting between the first block and the cement continuous wall.
Further comprising grooving a space between the cement continuous wall and the wale band.

8. The method of claim 7,
At least one connection block is formed between the first block and the second block such that both the front and back surfaces of the first and second blocks correspond to the inclination of the back surface of the first block and are inserted between the first block and the second block,
Wherein the connecting block is inserted between the second block and the cement continuous wall.

8. The method of claim 7,
Wherein the connecting portion of the first block is a hook portion into which the belt is inserted so that the first block can be supported by being suspended from the wale.

8. The method of claim 7,
A main receiving portion formed to protrude from a back surface of the first block is formed in a lower portion of the first block and a main fitting portion into which a main receiving portion of the first block is inserted is formed on a lower front surface of the second block And the second block is supported on the first block.

8. The method of claim 7,
The first block is continuously installed along the longitudinal direction of the band,
Wherein an auxiliary support portion formed to protrude from a side surface of the first block is formed on the lower surface of the first block and an auxiliary fitting portion into which the auxiliary support portion of the first block adjacent to the first block is inserted is formed on the lower surface of the first block, Wherein the first blocks disposed successively are interconnected.

The method according to claim 1,
A supporting member is mounted on a lower side of a space between the wale band and the cement continuous wall, a supporting plate is placed on the supporting frame, and a filling material is placed on the supporting plate to perform a groove filling operation between the wale band and the cement continuous wall,
Wherein the supporting bar comprises a mounting part detachably installed on the wale band and a supporting bar hingably coupled to the mounting part and horizontally disposed below the space between the wale band and the cement continuous wall when rotated in one direction. Wall construction method.

13. The method of claim 12,
And a connecting rod that is elastically compressible and stretchable between the supporting bar and the mounting portion and elastically presses the supporting bar to the lower side of the space between the wale band and the cement continuous wall is installed.

13. The method of claim 12,
The mounting portion is vertically disposed,
And a hook portion is formed on an upper end of the mounting portion so as to be able to be hooked on the wale band.

15. The method of claim 14,
The hooks are provided with resiliently compressible and stretchable braces,
Wherein the brace is supported between the hook and one side of the strap so that the brace elastically presses the strap to the other side of the strap.

The earth retaining wall is made by the construction method according to any one of claims 1, 3, and 5 to 15.