JP6672016B2 - Ground improvement method under the existing structure - Google Patents

Description

  The present invention provides a solidification improvement body in the ground immediately below an existing structure such as a building or a structure to improve the ground to a solid ground that can stably support the existing structure on the upper side of the existing structure. It relates to a ground improvement method.

  Conventionally, as a ground improvement method for improving the ground, as shown in FIG. 22, a construction machine inserts a pipe rod 32 provided with a head 33 to a predetermined depth in the ground, and after insertion, rotates the pipe rod 32. At the same time, a hardening material such as cement milk is injected at high speed and high pressure from the injection nozzle 34 of the head 33. Then, the ground is cut with the injection energy of the hardening material, and the hardened material injected and the ground are mixed and stirred. By pulling the pipe rod 32 upward while rotating, the vertical solidification is formed in the ground. There is known a structure in which an improved body Tc is formed to improve the ground.

  In this ground improvement method, a vertical columnar consolidation improvement body Tc is formed in the ground immediately below the existing structure K such as a building or a structure, so that the upper existing structure K can be stably supported. And the ground may be improved. This is achieved by inserting the pipe rod 32 very close to the existing structure K and injecting the hardening material from the injection nozzle 34 of the head 33 as shown in FIG. By forming a part of the vertical columnar consolidation improvement body Tc and performing a plurality of this along the existing structure K, the ground immediately below the existing structure K is improved to a solid ground.

  In the conventional method for improving the ground immediately below the existing structure K, when the ground immediately below the existing structure K is improved, a consolidated improvement body Tc is formed in the ground immediately below the existing structure K. As shown by hatching in FIG. 23, the solidification improved body Tc is formed in the ground other than immediately below the existing structure K, that is, the ground in unnecessary places other than the ground immediately below the existing structure K is also improved. Therefore, a large amount of hardening material such as cement milk is used. As a result, there is a possibility that the construction cost of the ground improvement work will increase significantly or the construction period will be prolonged.

  In addition, since the vertical columnar consolidated improvement body Tc is formed in the ground immediately below the existing structure K, the ground strength is significantly reduced until the consolidated improvement body Tc is solidified. When the consolidated improvement body Tc is formed in the ground immediately below the existing structure K, there is a possibility that the existing structure K such as an upper building or a structure partially displaces, such as a subsidence. .

  Therefore, the present invention has been made in view of such a problem, and an object of the present invention is to improve a ground immediately below an existing structure, and to improve a ground immediately below the existing structure, a plurality of walls arranged in parallel from both left and right sides. An existing structure that eliminates the need to improve the ground in unnecessary places other than immediately below the existing structure by creating a solidified improvement body, reduces the cost of ground improvement work, and shortens the construction period It is to provide a ground improvement method directly below.

The first invention is an existing structure that improves the ground to a solid ground that can stably support the existing structure on the upper side by forming a consolidated improvement body in the ground immediately below the existing structure such as a building or a structure. This is a ground improvement method immediately below, in which a construction machine inserts a pipe rod to a predetermined depth in the ground, and after insertion, injects a hardening material in a lateral direction from an injection nozzle provided on the pipe rod to inject the hardening material. By pulling out the pipe rod and performing upward , a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is opposite to one of the left and right sides of the existing structure and the opposite. By performing from the left and right sides with the left and right other sides, a plurality of wall-shaped consolidation improvement bodies are arranged in parallel so as to face left and right in the ground on each of the left and right sides directly below the existing structure, and at the same time, directly under the existing structure Parallel in the ground on each side In a plurality of wall-shaped consolidation improvement bodies, a predetermined gap is provided between adjacent consolidation improvement bodies, and the plurality of consolidation improvement bodies formed in the ground on one of the left and right sides immediately below the existing structure. This is a ground improvement method immediately below an existing structure in which a body and a plurality of consolidated improvement bodies formed in the ground on the other side are arranged so as to be shifted laterally from each other .

The second invention relates to an existing structure for improving the ground to a solid ground capable of stably supporting the existing structure on the upper side by forming a consolidated improvement body in the ground immediately below the existing structure such as a building or a structure. This is a ground improvement method immediately below, in which a construction machine inserts a pipe rod to a predetermined depth in the ground, and after insertion, injects a hardening material in a lateral direction from an injection nozzle provided on the pipe rod to inject the hardening material. By pulling out the pipe rod and performing upward, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is opposite to one of the left and right sides of the existing structure and the opposite. By performing from the left and right sides with the left and right other sides, a plurality of wall-shaped consolidation improvement bodies are arranged in parallel so as to face left and right in the ground on each of the left and right sides directly below the existing structure, and at the same time, directly under the existing structure Parallel in the ground on each side In a plurality of wall-shaped consolidation improvement bodies, a gap is provided between adjacent consolidation improvement bodies, and after a curing period of the consolidation improvement body formed with an interval, a pipe rod is provided in each of the gaps. The hardening material is sprayed from the spray nozzle provided at the site to form a wall-shaped consolidation improvement body, so that the consolidation improvement body is formed in all the ground immediately below the existing structure The ground improvement immediately below the existing structure Is the way.

The third invention is an existing structure for improving a ground to a solid ground capable of stably supporting an existing structure on an upper side by forming a consolidated improvement body in the ground immediately below the existing structure such as a building or a structure. This is a ground improvement method immediately below, in which a construction machine inserts a pipe rod to a predetermined depth in the ground, and after insertion, injects a hardening material in a lateral direction from an injection nozzle provided on the pipe rod to inject the hardening material. By pulling out the pipe rod and performing upward, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is opposite to one of the left and right sides of the existing structure and the opposite. By performing from the left and right sides with the left and right other sides, a plurality of wall-shaped consolidation improvement bodies are arranged in parallel so as to face left and right in the ground on each of the left and right sides directly under the existing structure, and Construction machines that produce compacted This is a small-sized construction machine, which performs dynamic observations around the solidified body to be formed in the ground on each of the left and right sides immediately below the existing structure, and based on the results of the dynamic observation, creates the next position where the solidified body is formed. Obtain the target position, move the self-propelled small construction machine to the found creation target position, and create a wall-like consolidated improvement body with the self-propelled small construction machine at the creation target position Ground improvement just under the existing structure Is the way.

According to a fourth aspect of the present invention, there is provided the third aspect of the invention, further comprising arithmetic processing means for storing formation target position calculation data for obtaining a formation target position which is a position at which the next consolidated improvement body is formed. This is a ground improvement method immediately below an existing structure which is obtained by automatically calculating a construction target position based on target position calculation data .

The fifth invention is an existing structure for improving the ground to a solid ground capable of stably supporting the existing structure on the upper side by forming a consolidated improvement body in the ground immediately below the existing structure such as a building or a structure. This is a ground improvement method immediately below, in which a construction machine inserts a pipe rod to a predetermined depth in the ground, and after insertion, injects a hardening material in a lateral direction from an injection nozzle provided on the pipe rod to inject the hardening material. By pulling out the pipe rod and performing upward, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is opposite to one of the left and right sides of the existing structure and the opposite. By performing it from the left and right sides with the left and right other sides, a plurality of wall-shaped consolidation improvement bodies are arranged in parallel so as to face left and right in the ground on each of the left and right sides immediately below the existing structure, and the left and right sides of the existing structure If uneven settlement occurs in By constructing a plurality of consolidated compacts intensively in the ground on one of the left and right sides immediately below the existing structure where the amount of subsidence of the structure is small, and constructing a plurality of consolidated compacts intensively in the ground, This is a ground improvement method immediately below an existing structure in which one of the left and right sides of the existing structure is lowered to a predetermined depth .

According to a sixth aspect of the present invention, in the fifth aspect, when a plurality of consolidated improvement bodies are intensively formed in the ground on one of the right and left sides immediately below the existing structure, dynamics around the consolidated improvement body formed in the ground This is a ground improvement method underneath an existing structure in which an observation is made and a consolidation improvement body is created in the ground based on the results of dynamic observation .

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, when forming a wall-shaped consolidated improvement body in the ground, the pipe rod inserted into the ground is swung about its axis. This is a ground improvement method immediately below an existing structure in which a hardening material is horizontally injected from an injection nozzle while the injection nozzle is being sprayed .

  According to the present invention, the formation of a wall-shaped consolidation improvement body in the ground is performed from the left and right sides of the left and right one sides of the existing structure and the opposite left and right sides, and the left and right sides immediately below the existing structure are formed. A solid ground that can stably support the ground immediately below the existing structure by forming a plurality of wall-shaped consolidation improvement bodies in parallel so that they face each other on both sides of the ground Can be improved to In addition, when improving the ground immediately below the existing structure, most of the wall-shaped consolidated improvement body is formed in the ground immediately below the existing structure. There is no development. Thus, by improving the ground only in the necessary places, it is possible to eliminate the use of a large amount of hardening material, to reduce the cost of the ground improvement work, and to greatly shorten the work period.

  Further, when forming a plurality of consolidated improvement bodies in the ground on each of the right and left sides immediately below the existing structure, the plurality of consolidated improvement bodies are arranged in parallel with a predetermined gap therebetween. The ground is always left on both sides of the solidified body, and the ground remaining on both sides of the solidified body does not significantly lower the ground strength. Thereby, the structural displacement of the existing structure such that the existing structure on the upper part partially sinks hardly occurs, and the consolidated improvement body can be formed extremely well.

  A plurality of wall-shaped consolidation improvement bodies are formed side by side in parallel in the ground on each of the left and right sides immediately below the existing structure, and after the curing period of the formed consolidation improvement bodies, a pipe is inserted into each gap. By injecting the hardening material from the injection nozzle provided on the rod and forming a wall-shaped consolidated improvement body here, it is possible to form a solidified improved body without gaps in all the ground immediately below the existing structure, The ground immediately below the existing structure can be improved to a stronger ground. As a result, even if the existing structure is a heavy structure or building, the existing structure can be stably supported, and a part of the existing structure sinks and the existing structure tilts or its Partial breakage can be reliably prevented.

  An arithmetic processing means for storing development target position calculation data for obtaining the development target position is provided. The arithmetic processing means automatically calculates and obtains the development target position from the development target position calculation data, so that the optimum fixed position is always obtained. It is possible to determine the order of forming the sintering improver and inform the operator of the order. This makes it possible to easily and satisfactorily perform the ground improvement work for forming the consolidated improved body to improve the solid ground, thereby improving the work efficiency.

  If unequal settlement occurs on the left and right of the existing structure, a plurality of consolidation improvement bodies are intensively formed in the ground on one of the left and right sides immediately below the existing structure, where the amount of settlement of the existing structure is small, and By forming the sinter improvement body intensively in the ground, the left and right one sides of the existing structure are settled to a predetermined depth, whereby the left and right inclination of the existing structure can be corrected. As a result, the existing structure tilted due to uneven settlement can be returned to a normal state.

It is explanatory drawing of the apparatus used in the ground improvement method immediately under the existing structure of this invention. It is a front view of the head provided in the front-end | tip of a pipe rod. It is a bottom view of the head provided in the front-end | tip of a pipe rod. It is a bottom view of another head provided in the tip of a tube rod. (A) It is a process figure of creation of a consolidation improvement object. (B) It is a process drawing of creation of a solidification improvement object. (C) It is a process drawing of creation of a consolidation improvement object. (D) It is a process drawing of creation of a consolidation improvement object. (E) It is a process drawing of creation of a consolidation improvement object. (F) It is a process drawing of creation of a consolidation improvement object. It is explanatory drawing of the wall-shaped consolidation improvement body formed in the ground. It is explanatory drawing of another wall-shaped consolidation improvement body formed in the ground. (D) It is a process drawing of creation of another consolidation improvement object. (E) It is a process drawing of creation of another consolidation improvement object. (F) It is a process drawing of creation of another consolidation improvement object. It is explanatory drawing which shows the example which injects a hardening | curing material while rocking a pipe rod, and produces a consolidation improvement body. It is the explanatory view which looked at a plurality of consolidation improvement bodies formed in the ground by the ground improvement method under the existing structure of the present invention from the front. It is the explanatory view which looked at a plurality of consolidation improvement bodies formed in the ground by the ground improvement method just under the existing structure of the present invention from the upper surface. It is explanatory drawing which looked at several consolidation improvement bodies formed in the ground in the ground improvement method immediately under the existing structure of this invention from diagonally. It is the expansion explanatory drawing which looked at another several consolidation improvement bodies formed in the ground from the upper surface. It is explanatory drawing which looked at another several consolidation improvement bodies formed in the ground from the upper surface. It is explanatory drawing which shows the formation order at the time of constructing several consolidated improvement bodies in the ground improvement method immediately under the existing structure of this invention. It is the explanatory view which looked at a plurality of consolidation improvement bodies formed in ground in another embodiment of the ground improvement method under the existing structure of the present invention from the upper surface. (A) It is explanatory drawing of the uneven settlement of the existing structure. (B) It is explanatory drawing of the unequal settlement of the existing structure. It is explanatory drawing which shows one process of another embodiment of the ground improvement method just under the existing structure of this invention. It is explanatory drawing which shows one process of another embodiment of the ground improvement method just under the existing structure of this invention. It is explanatory drawing which shows one process of another embodiment of the ground improvement method just under the existing structure of this invention. It is explanatory drawing of the ground improvement method of improving the conventional ground. It is the explanatory view which looked at the solidification improvement object formed in the ground just under the existing existing structure from the upper surface.

An embodiment of the ground improvement method immediately below an existing structure according to the present invention will be described.
The device used in the ground improvement method immediately below the existing structure will be described. As shown in FIG. 1, a construction machine for inserting or removing the pipe rod 2 to a predetermined depth in the ground is provided. It is a self-propelled small construction machine 1 such as a simple small pile driver. However, the construction machine is not limited to the self-propelled small construction machine 1, but may be a boring machine or another large construction machine according to the scale of improvement such as the construction depth of ground improvement.

  In this self-propelled small construction machine 1, a mast 3 is erected, and the pipe rod 2 is attached vertically along the mast 3, and the pipe rod 2 is placed on the top of the mast 3 in the ground. And a rotating device 5 for rotating the tube rod 2 are provided respectively. The pipe rod 2 is a hollow steel pipe through which a hardening material, compressed air, or the like passes, and has a head 6 provided with an injection nozzle 24 at a lower end thereof.

  Further, peripheral equipment of the self-propelled small construction machine 1 is a facility for supplying a hardening material or compressed air to the pipe rod 2 attached to the self-propelled small construction machine 1. The hardener is cement milk. However, the hardening material is not limited to this, and may be a mixture of cement milk with various additives or the like. The equipment for supplying the compressed air is the compressor 11, and supplies the compressed air from the compressor 11 to the pipe rod 2 via the flow meter 12. In addition, a mixing device 13 for supplying cement milk is provided. In the mixing device 13, a cement raw material flows in from a cement silo 114, and water flows in from a water tank 15 having a submersible pump 16. Generate Then, the produced cement milk is supplied via a flow meter 17 to a hardening material supply device 18 having a high-pressure pump 19, and the hardening material supply device 18 supplies the cement milk to the pipe rod 2. Although not shown, each device has a generator.

  On the other hand, the head provided at the distal end which is the lower end of the tube rod has a plurality of bits 21 attached to the distal end side as shown in FIGS. 2 and 3, and has horizontal wings 22 protruding laterally on both left and right sides. A bit 23 is also attached to the lower part of the horizontal wing 22. Further, the horizontal wing 22 is provided with injection nozzles 24 communicating with the inside of the pipe rod 2 in the lateral direction, and the injection nozzles 24 are arranged on the left and right sides of the horizontal wing 22, for example, two in a row. The two injection nozzles 24 are directed in the same direction, and inject the cement milk, which is a hardening material, from the two injection nozzles 24 in a state parallel to the horizontal direction. The number of the injection nozzles 24 is not limited to two arranged side by side, but may be one or three or more. Moreover, although a plurality of them are arranged side by side, a plurality of them may be arranged vertically and further, and a plurality of them may be arranged both vertically and horizontally. When a plurality of injection nozzles 24 are arranged vertically, the injection nozzles 24 are provided directly on the head 6 without the horizontal blades 22.

  The injection nozzle 24 provided in the head 6 directs two or more injection nozzles 24 in the same direction, from which the cement milk is injected in a state parallel to the horizontal direction. Thus, three injection nozzles 24 are arranged side by side in the longitudinal direction (lateral direction) of the horizontal blade, and the three injection nozzles 24 direct the centrally located injection nozzle 24 straight forward and The injection nozzles 24 located on both the left and right sides are slightly shifted toward the center side, and are directed forward so that the cross-injection in which the cement milk injected from the three injection nozzles 24 intersects at one point where the cement milk has been injected. good.

  In the above-described apparatus, the head 6 is provided at the distal end, which is the lower end of the tube rod 2, and the jet nozzle 24 is provided in the head 6. However, the head 6 may not be provided, and the structure of the tube rod 2 alone may be used. In this case, the injection nozzle 24 is provided directly on the pipe rod 2.

  Next, a method for improving the ground immediately below an existing structure using the apparatus having such a configuration will be described.

  First, as a method of forming the consolidated improvement body T in the ground, a self-propelled small construction machine 1 as a construction machine is installed at a predetermined position, and as shown in FIG. If the pipe rod 2 attached to the construction machine 1 is rotated, it is inserted into the ground. At this time, as shown in FIG. 5 (b), the ground is excavated by the head 6 provided on the pipe rod 2, but in order to assist the insertion of the pipe rod 2, compressed air or Perform while spraying water or the like. Then, as shown in FIG. 5C, after inserting the tube rod 2 to a predetermined depth, the rotation of the tube rod 2 and the head 6 is stopped. Then, cement milk, which is a hardening material, is injected into the ground from the injection nozzle 24 of the head 6 at a high speed and a high pressure in a lateral direction, and the ground is cut with the injection energy of the cement milk to mix and agitate the injected cement milk and the ground. This is performed upward while pulling out the pipe rod 2, thereby forming a wall-shaped consolidated improvement body T in the ground.

  Specifically, after inserting the pipe rod 2 to a predetermined depth, the injection rod 24 of the head 6 provided on the pipe rod 2 is turned sideways as shown in FIG. With the cement milk and compressed air supplied to the tube rod 2 in a stopped state or while the tube rod 2 is rocking about its axis, the cement milk is injected into the ground at high speed and high pressure from the injection nozzle 24 of the head. The cement milk is injected linearly, and the injection of the cement milk is performed, for example, for several tens of seconds, and the ground is cut and mixed with the injection energy of the cement milk to mix and agitate the injected cement milk to improve the consolidation in the ground. Create the first stage of T. When the pipe rod 2 is rocked, the rocking angle is about 4 to 15 degrees.

  Then, the pipe rod 2 is pulled out several centimeters to several tens centimeters and moved upward. As shown in FIG. 6 (e), the cement milk is injected into the ground from the injection nozzle 24 of the head 6 at the position moved upward. It is jetted linearly at high speed and high pressure to form the second stage of the consolidated improved body T as in the first stage. Further, this is repeated to form the third, fourth, and fifth stages of the consolidated improved body T in this order, and as shown in FIG. Create. By injecting the cement milk while sequentially pulling out the pipe rod 2 and moving upward in this way, the consolidated improved body T is formed stepwise upward.

  Thereby, when the cement milk is injected from the injection nozzle 24 into the ground when the pipe rod 2 is stopped without rotating, as shown in FIG. A consolidated improvement body T is formed, and such a wall-shaped consolidated improvement body T is formed in the ground to improve the ground. Also, when the cement milk is injected from the injection nozzle 24 into the ground while swinging the pipe rod 2 around the axis thereof, as shown in FIG. Is formed, and such a wall-shaped consolidated improvement body T is formed in the ground to improve the ground. Then, after forming the wall-shaped consolidated improvement body T in the ground, the self-propelled small-sized construction machine 1 pulls out the pipe rod 2 from the ground, and the work here is completed.

  Regarding the formation of the wall-shaped consolidation improvement body T in the ground, the injection of the cement milk into the ground was stopped for several centimeters after the pipe rod 2 was stopped without moving upward. By pulling out several tens of centimeters from and moving upward, and then jetting in a stopped state again, the consolidated improved body T is formed stepwise upward, as shown in FIG. 9 (d). As shown in (e) and (f), the cement milk is injected into the ground while moving upward at a low speed without stopping the pipe rod 2, thereby continuously continuously upward. The consolidation improved body T may be formed. At this time, the cement milk is injected from the injection nozzle 24 into the ground while the pipe rod 2 is stopped without rotating or while the pipe rod 2 swings around its axis.

  In the case where the cement milk is injected from the injection nozzle 24 into the ground while swinging the pipe rod 2 about its axis (for example, the swing angle is about 4 to 15 degrees), the above-described injection is performed. If three nozzles 24 are arranged side by side and a cross-injection (shown in FIG. 4) in which the cement milk injected from the three injection nozzles 24 intersects at a single point where the cement milk is injected is used, FIG. As shown in FIG. 10, it is possible to form a very good solidified improved body T having a rectangular shape in plan view in the ground.

  Then, the wall-shaped consolidated improvement body T formed in the ground by such a method is formed in the ground immediately below the existing structure. This is because the formation of the wall-shaped consolidation improvement body T is performed from the left and right sides of the left and right one side of the existing structure and the opposite left and right other sides, so that the ground on each of the right and left sides immediately below the existing structure is formed. A plurality of wall-shaped consolidation improvement bodies T are formed side by side in parallel so as to face each other. The existing structure is a structure such as a box culvert B used as an underground passage, a waterway, a storage tank, and an underground conduit for a communication line. However, the present invention is not limited to this, and may be another structure such as a storage tank, or another structure such as a house or a warehouse.

  More specifically, as shown in FIGS. 11, 12, and 13, on one of the left and right sides of the existing box culvert B, a plurality of compacted improvement bodies T are arranged in parallel in the ground immediately below the box culvert B. And build it up. Note that the left and right here are the left and right width directions of the box culvert B in a direction orthogonal to the longitudinal direction that is the length direction of the box culvert B. Then, at this time, a gap is provided between adjacent consolidated improvement bodies T. This gap is a predetermined gap and has substantially the same size as the width of the consolidated improvement body T to be formed. The length in the longitudinal direction of the consolidated improvement body T (the distance that the cement milk injected from the injection nozzle 24 reaches) is substantially half the width of the left and right sides of the box culvert B, and is one of the left and right sides of the box culvert B. It is the length that reaches from the side to the left and right middle part. Then, a plurality of consolidated compacts T arranged in parallel with a predetermined gap are formed over the entire left or right side of the box culvert B.

  Also, on the left and right other sides opposite to the left and right one sides of the box culvert B, a plurality of consolidated improvement bodies are formed so as to face the plurality of consolidated improvement bodies T formed on the left and right one sides in the ground immediately below the box culvert B. T is arranged in parallel and formed. Also, at this time, a predetermined gap is left between the adjacent consolidated improvement bodies T, and the plurality of consolidated improvement bodies T formed on the left and right sides are also replaced with the plurality of consolidated improvement bodies formed on the left and right sides. It is similar to the body T. Then, the plurality of consolidated consolidation bodies T arranged in parallel with a predetermined gap are formed over the entire left and right sides of the box culvert B.

  Then, a plurality of consolidated improvement bodies T formed in the ground on one of the left and right sides immediately below the box culvert B and a plurality of consolidated improvement bodies T formed in the ground on the other side of the left and right sides are mutually horizontal (in FIG. 12). In the vertical direction). Thereby, in the ground immediately below the box culvert B, a plurality of consolidated improvement bodies T arranged in parallel with a predetermined gap formed on one side on the left and right and parallel with a predetermined gap formed on the other side on the left and right sides Are formed so that the plurality of consolidated consolidation improved bodies T arranged side by side are shifted from each other and do not overlap.

  The plurality of consolidated improvement bodies T formed in the ground on one of the left and right sides directly below the box culvert B and the plurality of consolidated improvement bodies T formed in the ground on the other side of the left and right sides are placed side by side with each other. Although they are shifted so as not to overlap, they may be slightly overlapped as shown in FIG.

  Further, in the plurality of consolidated improvement bodies T formed in the ground on one of the right and left sides or the other side on the right and left sides immediately below the box culvert B, the gaps between the adjacent consolidated improvement bodies T are all predetermined as described above. Although the gap is substantially the same as the gap, the gap is not limited to this. For example, as shown in FIG. 15, the gap is narrowed in a plurality of consolidated improvement bodies T formed at the center of the box culvert B. In addition, the gaps between the adjacent consolidated improvement bodies T may be increased as necessary, such as to increase the gap between the plurality of consolidated improvement bodies T formed away from the center of the box culvert B. You may make it different.

  As described above, the formation of the wall-shaped consolidated improvement body T in the ground is performed from the left and right sides of the left and right sides of the existing box culvert B and the opposite side, and the box culvert is formed. By arranging a plurality of wall-shaped consolidation improvement bodies T in parallel so as to face left and right in the ground on each of the right and left sides directly below B, the ground immediately below the box culvert B and the upper box culvert B in a stable manner. It can be improved to a solid ground that can be supported. Further, at this time, the plurality of consolidated improvement bodies T formed in the ground on one of the left and right sides immediately below the box culvert B and the plurality of consolidated improvement bodies T formed in the ground on the other side of the left and right sides are shifted laterally from each other. In this case, there is no other consolidated improvement body T around the periphery including the tip of the consolidated improvement body T to be formed, and the ground always exists. Thus, for example, when forming the consolidated improved body T on one of the right and left sides, the consolidated improved body T formed on the other side is not adversely affected or hindered, and the consolidated improved body T is formed. It can be formed well.

  Moreover, when the ground immediately below the box culvert B, which is an existing structure, is improved, most of the wall-like consolidated improvement body T is formed in the ground immediately below the box culvert B. The compacted body T is not formed. By improving the ground only in the necessary places and eliminating the need to improve the ground in unnecessary places, this eliminates the use of a large amount of hardened material such as cement milk and reduces the cost of ground improvement work. And the construction period can be greatly reduced.

  Further, when forming a plurality of consolidated improvement bodies T in the ground on each of the left and right sides immediately below the existing structure, the box culvert B, the plurality of consolidated improvement bodies T are arranged in parallel with a predetermined gap therebetween. Therefore, the ground is always left on both sides of each consolidated improvement body T, and the ground remaining on both sides of the consolidated improvement body T does not significantly lower the ground strength. Thereby, the displacement of the structure of the box culvert B such that the upper box culvert B partially sinks hardly occurs, and the consolidated improved body T can be formed extremely well.

  Next, in the ground improvement method immediately below the existing structure, a plurality of wall-shaped consolidation improvement bodies T are arranged in parallel in the left and right sides of the ground immediately below the existing structure, the box culvert B, so as to face each other. The order in which they are created will be described.

  FIG. 16 shows the order of forming the consolidated improved body T. The numbers circled in FIG. 16 indicate the order.

  First, a consolidated improvement body T is formed in order on both left and right corners of the existing box culvert B, and then the consolidated improvement body T is sequentially formed on both left and right corners of the box culvert B. That is, the consolidated improved body T is sequentially formed at the four corners on the left and right sides and the left and right other sides of the box culvert B. Then, a consolidated improved body T is formed at a central position on one of the left and right sides of the box culvert B, and thereafter, a consolidated improved body T is formed at a position near the center on the other of the left and right sides of the box culvert B. Then, a consolidated improvement body T is formed at each of two places on the left and right sides of the box culvert B that do not approach each other, and thereafter, a consolidated improvement body T is formed at a position near the center of the other side of the box culvert B, and And the consolidation improved body T is formed at other positions. In this way, by forming the next consolidated improved body T at a position as far as possible from the previously formed position on one of the left and right sides and the other side on the left and right sides of the box culvert B, the uncured solidified body during curing is formed. A new consolidated improved body T is not formed near the sintered improved body T. The formation of the consolidated improved body T varies depending on the size of the consolidated improved body T to be formed, but is usually about 4 to 6 per day. In addition, a curing period of about 1 day to about 3 days is required as a curing period until the formed consolidated improved body T is solidified and has sufficient strength.

  Further, when the compacted improvement body T is formed in the order described above, since the construction machine is the self-propelled small-sized construction machine 1, the position where the next consolidated improvement body T is formed is a distant position. However, the self-propelled small-sized construction machine 1 can be easily and quickly moved from the position where the previous consolidated improved body T is formed to the position where the next consolidated improved body T is formed. When the construction machine is a large-sized construction machine such as a boring machine, it takes a lot of time to move the machine alone. Although the consolidated improved body T was formed, that is, a new consolidated improved body T was sometimes formed near the consolidated improved body T during curing, but the construction machine was the self-propelled small construction machine 1. This makes it possible to move the self-propelled small construction machine 1 easily and in a short time, so that a new consolidated improved body T is not formed near the consolidated improved body T during curing. The compacted body T can be quickly formed at the position where the next compacted body T is to be formed, and the ground improvement work can be performed efficiently.

  In addition, in the order of forming the consolidated improvement body T, a dynamic observation around the consolidated improvement body T formed immediately below the existing structure, the box culvert B, is performed. A formation target position which is a position at which the consolidated improved body T is formed may be obtained, and the wall-shaped consolidated improved body T may be formed at the obtained formation target position.

  As described above, basically, as described above, the next consolidated improvement body T is formed at a position as far away from the previously formed position as possible, so that a new consolidated improvement body T during curing is newly formed. The formation of a compacted improved body T is prevented, and at the same time, the dynamics around the consolidated improved body T to be formed are observed. This dynamic observation means that the behavior of the structure is grasped by measuring the displacement of the existing structure by the inclinometer, the amount of settlement of the existing structure by the squat meter, and the amount of settlement of the ground surface by the squat meter, The behavior of the ground is grasped by measuring the displacement in the ground by an underground displacement meter having a plurality of inclinometers and the amount of settlement of each layer by a stratified subsidence meter having a plurality of strain sensors.

  Then, the behavior of the structure and the behavior of the ground are grasped by the dynamic observation, and based on the result of the dynamic observation, a formation target position, which is a position at which the consolidated improved body T is to be formed next, is obtained. As a method of obtaining this, when a large change appears in the behavior of the structure and the behavior of the ground grasped by dynamic observation, for example, in a distant range where the large change does not affect, the self-propelled small construction machine 1 Is determined as a formation target position which is a position at which the consolidated improved body T is formed next. However, in the case of performing ground improvement work using multiple self-propelled small construction machines 1, in consideration of the overall work efficiency, the self-propelled small Even in a place where the construction machine 1 moves a long distance, this may be determined as a formation target position which is a position where the consolidated improved body T is formed next.

  In addition, on the basis of the dynamic observation, the behavior of the structure and the behavior of the ground are grasped, and based on the result of the dynamic observation, a field engineer is required to obtain a formation target position, which is a position where the next consolidated improvement body T is to be formed. It is possible to determine the development target position by making a judgment based on the results of dynamic observation from the experience up to that time, but it is provided with an arithmetic processing means which is a computer such as a personal computer. The position is automatically calculated and obtained.

  This is because, in the arithmetic processing means, formation target position calculation data for obtaining a formation target position, which is a position where the next consolidated improvement body T is formed, is stored in advance. The data and various data from the past ground improvement work are combined to determine the optimum land formation target position in accordance with the behavior of the structure and the behavior of the ground as a result of dynamic observation. .

  Then, the arithmetic processing means automatically calculates and obtains a formation target position which is a position at which the consolidated improved body T is to be formed next, based on the development target position calculation data stored in advance. The creation target position is displayed on a display provided in the self-propelled small construction machine 1. Then, the operator operating the self-propelled small-sized construction machine 1 looks at the creation target position displayed on this display, and based on this, the self-propelled small-sized construction machine 1 is moved, and after the movement, the next consolidated consolidation improved body T is formed. The display may not be provided in the self-propelled small construction machine 1 but may be provided separately or in another place.

  In this way, dynamic observation around the solidified improved body T formed immediately below the existing structure, the box culvert B, is performed, and based on the result of the dynamic observation, the arithmetic processing means uses the development target position calculation data, By automatically calculating and obtaining a formation target position which is a position for forming the consolidated improved body T, and displaying this on a display, it is always possible to inform an operator of an optimum order of forming the consolidated improved body T. Can be. This makes it possible to easily and satisfactorily perform the ground improvement work of forming the consolidated improved body T and improving the solidified ground, thereby improving the work efficiency.

  In addition, by observing the dynamics around the consolidation improvement body T formed just below the box culvert B, it is possible to always grasp the behavior of the structure and the behavior of the ground. Accidents and the like can be avoided by detecting and changing the position at which the consolidated improved body T is formed next based on the result of the dynamic observation.

  Next, another embodiment of the ground improvement method immediately below the existing structure will be described. In this embodiment, the existing structure is the box culvert B as the existing structure. However, this is the case of the heavy construction C which is heavier than the box culvert B.

  In the case of the heavy construction C as an existing structure, it is necessary to improve the structure to a stronger ground that can stably support the upper heavy construction C. Therefore, in such a case, the ground is improved by the following method.

  First, as in the above-described embodiment, on one of the left and right sides of the existing heavy structure C, a plurality of consolidated improvement bodies T are formed in parallel in the ground immediately below the heavy structure C with a predetermined gap therebetween. At the same time, on the left and right sides opposite to the left and right one sides of the weight building C, by forming a plurality of consolidated improvement bodies T in parallel in the ground immediately below the weight building C with a predetermined gap therebetween, A plurality of wall-shaped consolidation improvement bodies T are formed in parallel on the right and left sides of the ground immediately below the heavy construction C so as to face each other. This is similar to that shown in FIG.

  Then, a plurality of wall-like consolidated improvement bodies T are formed side by side in parallel in the ground on each of the right and left sides immediately below the heavy construction C, and the formed consolidated improvement bodies T are solidified to have sufficient strength. That is, after the curing period of the consolidation improved body T has elapsed, cement milk is laterally injected into the respective gaps from the injection nozzle 24 provided on the pipe rod 2 in the same manner as described above, and this is upward. As a result, the wall-shaped consolidated improvement body T is formed here, and the solidified improved body T is formed in all the gaps, as shown in FIG. A plurality of wall-shaped consolidation improvement bodies T are formed side by side in the ground on both sides in parallel without leaving a gap, that is, the consolidation improvement bodies T are provided in all the ground immediately below the heavy construction C without any gaps. Create

  As described above, by forming the consolidated improvement body T without any gap in all the ground immediately below the existing heavy building C, the ground immediately below the heavy building C can be improved to a stronger ground. Thus, even if the existing structure is a heavy weight building C, the heavy building C can be stably supported, and a part of the heavy building C sinks and the heavy building C tilts or one of the two. It is possible to reliably prevent the part from being damaged.

  Further, another embodiment of the ground improvement method immediately below the existing structure of the present invention will be described. In this embodiment, this is performed when the existing structure is a building R such as a house or a warehouse, and uneven settlement occurs on the left and right of the building R as the existing structure. However, the existing structure is not limited to this, and may be another structure or the like. The construction machine is the self-propelled small construction machine 1, but is not limited to this, and may be a boring machine or another large construction machine.

  The unequal settlement of the building R, which is an existing structure, means that the ground surface is unevenly sunk and the building R is tilted. There are various causes. For example, as shown in FIG. If the soft layer S in the ground has a different thickness, the thicker the soft layer S, the larger the amount of settlement, and the unevenness of the ground surface causes the building R to tilt. Also, as shown in FIG. 18 (b), if the building R built on the soft ground is a building R with an uneven weight balance, the sinking amount of the heavy portion of the building R becomes large, whereby Since the ground surface sinks unevenly, the building R is inclined.

  Then, when such unequal settlement occurs on the left and right of the building R, as shown in FIG. 19, a plurality of consolidated improvement bodies T are placed in the ground on one of the left and right sides immediately below the building R where the settlement amount of the building R is small. Arrange in parallel and concentrate. When the plurality of consolidated improvement bodies T are formed intensively, the plurality of consolidated improvement bodies T are formed in the ground while leaving a gap between adjacent consolidated improvement bodies T or without any gap. I do. When an interval is provided between the consolidation improvement bodies T, the interval may be the above-mentioned predetermined interval or the interval may be narrow.

  A plurality of consolidated improvement bodies T formed in the ground by arranging a plurality of consolidated improvement bodies T in parallel in the ground on one of the left and right sides immediately below the building R where the settlement amount of the building R is small, thereby forming a plurality of consolidated improvement bodies T in the ground. By setting the ground strength to a reduced state, that is, temporarily setting the ground to a loosened state until is hardened, one of the left and right sides of the building R can be subsided.

  At this time, similar to the dynamic observation performed in the above-described embodiment, the dynamic observation around the consolidated improvement body T formed in the ground is performed, and the consolidated improved body T is embedded in the ground based on the result of the dynamic observation. Create. This is because, when constructing the consolidated improvement body T in the ground on one of the right and left sides immediately below the building R, dynamic observation is performed to determine the settlement amount of the building R, and based on this, as shown in FIG. In this building R, a consolidated improvement body T is formed in the ground on one of the left and right sides immediately below the building R until a predetermined depth at which the amount of settlement on one of the left and right sides is equal to the amount of settlement on the other side. Then, one of the left and right sides of the building R is settled.

  Then, when one of the left and right sides of the building R is lowered to a predetermined depth, the work of forming the consolidated improved body T is temporarily stopped. Then, after the plurality of consolidated improvement bodies T formed intensively in the ground on the left and right sides immediately below the building R have hardened and have sufficient strength, as shown in FIG. On the other side, which is opposite, on the other side, a plurality of consolidated improvement bodies T are formed in the ground immediately below the building R as in the above-described embodiment.

  In this way, the plurality of consolidated improvement bodies T are intensively formed in the ground on one of the left and right sides immediately below the building R where the settlement amount of the building R is small, and the left and right one sides of the building R are sunk to a predetermined depth. Thereby, the inclination of the building R on the left and right can be corrected, whereby the building R inclined by uneven settlement can be returned to a normal state. In addition, along with this, it is possible to improve the structure to a strong ground that can stably support the upper building R.

  DESCRIPTION OF SYMBOLS 1 ... Self-propelled small construction machine, 2 ... Tube rod, 3 ... Mast, 4 ... Elevating device, 5 ... Rotating device, 6 ... Head, 11 ... Compressor, 12 ... Flow meter, 13 ... Mixing device, 14 ... Cement silo , 15 ... water tank, 16 ... submersible pump, 17 ... flow meter, 18 ... hardening material supply device, 19 ... high pressure pump, 21 ... bit, 22 ... horizontal blade, 23 ... bit, 24 ... injection nozzle, 32 ... pipe rod, 33: head, 34: injection nozzle

Claims (7)

A ground improvement method under the existing structure, in which a consolidated improvement body is created in the ground immediately below the existing structure such as a building or a building to improve the ground to a solid ground that can stably support the existing structure above So,
Insert the pipe rod to a predetermined depth in the ground with the construction machine, and after inserting, inject the hardening material in the horizontal direction from the injection nozzle provided on the pipe rod, and eject the hardening material upward while pulling out the pipe rod. By performing, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is performed from the left and right sides of the left and right one sides of the existing structure and the opposite left and right sides. By constructing a plurality of wall-shaped consolidation improvement bodies in parallel so as to face left and right in the ground on each of the left and right sides immediately below the existing structure,
In a plurality of wall-shaped consolidation improvement bodies formed in parallel in the ground on each of the left and right sides immediately below the existing structure, a predetermined gap is provided between adjacent consolidation improvement bodies, Immediately below the existing structure, wherein a plurality of consolidated improvement bodies formed in the ground on one side and a plurality of consolidated improvement bodies formed in the ground on the left and right sides are arranged so as to be laterally offset from each other. Ground improvement method. A ground improvement method under the existing structure, in which a consolidated improvement body is created in the ground immediately below the existing structure such as a building or a building to improve the ground to a solid ground that can stably support the existing structure above So,
Insert the pipe rod to a predetermined depth in the ground with the construction machine, and after inserting, inject the hardening material in the horizontal direction from the injection nozzle provided on the pipe rod, and eject the hardening material upward while pulling out the pipe rod. By performing, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is performed from the left and right sides of the left and right one sides of the existing structure and the opposite left and right sides. By constructing a plurality of wall-shaped consolidation improvement bodies in parallel so as to face left and right in the ground on each of the left and right sides immediately below the existing structure,
In a plurality of wall-shaped consolidation improvement bodies that are formed in parallel in the ground on each of the left and right sides immediately below the existing structure , a consolidation improvement that is formed with an interval between adjacent consolidation improvement bodies and with an interval After the aging period of the body, the hardening material is sprayed from the spray nozzles provided on the pipe rods into each gap to form a wall-shaped consolidated improvement body, which solidifies in all the ground immediately below the existing structure. A ground improvement method immediately below an existing structure, comprising forming a knot improving body. A ground improvement method under the existing structure, in which a consolidated improvement body is created in the ground immediately below the existing structure such as a building or a building to improve the ground to a solid ground that can stably support the existing structure above So,
Insert the pipe rod to a predetermined depth in the ground with the construction machine, and after inserting, inject the hardening material in the horizontal direction from the injection nozzle provided on the pipe rod, and eject the hardening material upward while pulling out the pipe rod. By performing, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is performed from the left and right sides of the left and right one sides of the existing structure and the opposite left and right sides. By constructing a plurality of wall-shaped consolidation improvement bodies in parallel so as to face left and right in the ground on each of the left and right sides immediately below the existing structure,
Construction machinery to construct a consolidated improvement of wall-like in soil, the self-propelled and compact construction machine performs kinetics observed near caking improved body Construction on both left and right sides of each in the ground just below the existing structures Then, based on the results of the dynamic observation, the target formation position for the next formation of the consolidated improvement body is found, and the self-propelled small-sized construction machine is moved to the found formation target position, and the self-propelled small-sized construction is performed at the formation target position A ground improvement method immediately below an existing structure, comprising forming a wall-shaped consolidation improvement body with a machine. Next, there is provided processing means for storing formation target position calculation data for obtaining a formation target position which is a position for forming a consolidated improvement body, and the formation target position is automatically determined by the formation target position calculation data in the calculation processing means. The method for improving the ground immediately below an existing structure according to claim 3, wherein the method is obtained by calculation. A ground improvement method under the existing structure, in which a consolidated improvement body is created in the ground immediately below the existing structure such as a building or a building to improve the ground to a solid ground that can stably support the existing structure above So,
Insert the pipe rod to a predetermined depth in the ground with the construction machine, and after inserting, inject the hardening material in the horizontal direction from the injection nozzle provided on the pipe rod, and eject the hardening material upward while pulling out the pipe rod. By performing, a wall-shaped consolidated improvement body is formed in the ground, and the formation of the wall-shaped consolidated improvement body is performed from the left and right sides of the left and right one sides of the existing structure and the opposite left and right sides. By constructing a plurality of wall-shaped consolidation improvement bodies in parallel so as to face left and right in the ground on each of the left and right sides immediately below the existing structure,
When unequal settlement occurs on the left and right of the existing structure, a plurality of consolidation improvement bodies are intensively created in the ground on one of the left and right sides immediately below the existing structure where the amount of settlement of the existing structure is small, and multiple consolidation A method of improving the ground immediately below an existing structure, wherein the left and right sides of the existing structure are sunk to a predetermined depth by intensively forming the improved body in the ground. When constructing multiple consolidated compacts intensively in the ground on one of the left and right sides immediately below the existing structure, make dynamic observations around the consolidated compacts that are formed in the ground, and perform ground observation based on the results of the dynamic observation. The ground improvement method immediately below an existing structure according to claim 5 , wherein a solidification improvement body is formed therein. When Construction caking improvement of wall-like in soil, claims, characterized in that injecting the hardening material laterally tubes rods inserted into the ground from the injection nozzle while swinging about its axis Item 7. The ground improvement method immediately below an existing structure according to any one of Items 1 to 6 .

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