JP7146432B2 - Dynamic injection device and dynamic injection method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a dynamic grouting device and a dynamic grouting method for injecting a grout material (chemical solution) into soft ground consisting of a sandy soil layer and a buried soil layer.

As a method of injecting a chemical solution called grout material into the ground during ground improvement, for example, static injection of statically injecting a chemical solution into the ground at a low pressure so that the chemical solution penetrates into the ground. There is dynamic injection in which the injection pressure or injection speed when injecting the chemical solution into the ground is set at a specific frequency, or pulsating pressures with several frequencies are superimposed to inject the chemical solution into the ground.

For example, dynamic injection is disclosed in Patent Documents 1 to 3. In Patent Document 1, for example, when injecting a cement or bentonite-based chemical solution into a cracked bedrock, a pulsating pressure having a specific frequency selected from a frequency range of 5 to 30 Hz is superimposed on the injection pressure, Exciting the constituent particles of the drug to improve permeability is disclosed. In addition, Patent Document 2 describes grouting in which a chemical solution is injected into a fissured bedrock and a sandy ground that is uniform in the vertical and horizontal directions. It discloses applying pulsating pressure by waves in a superimposed manner to excite constituent particles of the chemical solution to improve permeability. Furthermore, in Patent Document 3, the injection speed is increased or decreased in a cycle of 7 to 15 seconds, and the maximum and minimum values of the injection pressure are increased each time the injection speed is repeated. It is disclosed to efficiently infiltrate the chemical solution into the target range by suppressing the occurrence of cleft injection in which the chemical solution is injected.

In recent years, in addition to dynamic injection, the process of interrupting the injection of the liquid medicine for a predetermined time and then injecting the liquid medicine again is repeated to dissipate the injection pressure generated when injecting the liquid medicine and suppress the occurrence of cleft injection. An inching injection method has also been devised (see Patent Document 4).

Japanese Patent No. 3096244 Japanese Patent No. 5089430 Japanese Patent No. 3757400 JP 2015-25293 A

The above-mentioned Patent Document 1 has a hydraulic servo actuator and a positive displacement pump (for example, a piston pump) driven by the hydraulic servo actuator, and generates a pulsating pressure that changes the pressure by applying a secondary high frequency from an oscillator to the chemical liquid. I am using part. Such a pulsating pressure generating unit requires a large-scale apparatus and requires readjustment of a skilled servo unit in controlling the amplitude of the pulsating pressure. Further, Patent Document 2 uses a secondary high-frequency generator having a rotating disk provided with a plurality of transmission holes at predetermined angular intervals and a motor for rotating the rotating disk, as a device for applying high frequency to the injection pressure of the chemical solution. ing. The secondary high-frequency generator disclosed in Patent Document 2 has the advantage of being simpler than the pulsating pressure generator disclosed in Patent Document 1. However, when using the secondary high-frequency generator disclosed in Patent Document 2, the opening degree of the regulating valve installed in the bypass provided in the flow path of the chemical liquid is adjusted, and the pressure amplitude and flow rate amplitude are excessive. We need to prevent it from growing. Furthermore, the grouting method disclosed in Patent Document 1 and Patent Document 2 assumes the case of injecting a chemical solution into cracked rock, and is intended for soft ground consisting of a sandy soil layer and a buried soil layer. When this is done, the chemical solution is likely to diffuse, making it difficult to create a substantially spherical improved body in the ground.

In addition, in Patent Documents 3 and 4, the occurrence of splitting injection can be suppressed and the chemical solution can be penetrated into the target penetration range. When performing ground improvement using

In order to solve the above-described problems, the dynamic injection device of the present invention includes a delivery means for delivering the chemical solution in a state in which pulsation is added to the delivery speed or delivery pressure of the chemical solution for improving the ground, and the delivery means a switching member that repeats injection and interruption of the chemical solution to each of the plurality of positions of the ground by switching the flow path of the sent chemical solution a plurality of times, and the chemical solution is mixed by It contains a first chemical solution and a second chemical solution that serve as a grout material, and the delivery means is connected to a first flow channel for delivering the first chemical solution and a second channel for delivering the second chemical solution, and the first A pulsation is added to the delivery speed or delivery pressure of each of the chemical solution and the second chemical solution, and the first chemical solution is alternately delivered to the first flow path and the second chemical solution is delivered to the second flow path, respectively. and the flow path is a flow path formed by joining the first flow path and the second flow path .

Also, an air chamber provided corresponding to each of the first flow path and the second flow path and preventing addition of the pulsation to the delivery speed or delivery pressure of the first chemical solution or the second chemical solution ; and disabling means for disabling actuation of the air chamber.

In this case, the disabling means is provided corresponding to each of the first flow path and the second flow path, and prevents addition of pulsation to the delivery speed or delivery pressure of the first chemical solution or the second chemical solution. Preferably, it is a valve that opens and closes the flow path between the air chamber and the air chamber.

Further, the switching member includes a main body having an inlet into which the chemical solution is sent, and a plurality of delivery ports provided corresponding to the plurality of injection positions for delivering the chemical solution flowing in from the inlet. a feed passage disposed inside the main body and communicating with the feed port; and a feed passage communicating with any one of the plurality of delivery ports to deliver the fed chemical solution to one of the plurality of delivery ports. and a ball valve having a chemical liquid flow path consisting of a path.

In this case, the ball valve communicates with the chemical solution flow path, and communicates with the delivery port through which the chemical solution is sent out when the ball valve rotates in one direction, so that the chemical solution is sent into the chemical solution channel. It is preferable to have a relief channel that reduces the pressure applied to the chemical solution.

The chemical is characterized by being a non-Newtonian liquid chemical.

In addition, the delivery means is characterized by delivering the chemical solution that becomes the non-Newtonian grout material .

According to the present invention, a chemical solution can be effectively injected into a wide range of soft ground such as a sandy soil layer and a buried soil layer, and a good improved body can be created in the soft ground. can.

It is a figure which shows an example of a structure of the construction system of this embodiment. (a) is a front view of an infusion pump, and (b) is a right side view of the infusion pump. (a) is a cross-sectional view of the A liquid delivery part when the A liquid is delivered, (b) is a cross-sectional view of the B liquid delivery part when the A liquid is delivered in the A liquid delivery part, (c) is stored in the air chamber FIG. 4D is a cross-sectional view of the liquid A delivery section when delivering the liquid A stored in the air chamber, and a cross-sectional view of the liquid B delivery section when delivering the liquid A stored in the air chamber. It is a schematic diagram of a switching valve. FIG. 4 is a perspective view showing the structure of a ball valve of the switching valve; FIG. 10 is a cross-sectional view showing the operation of the ball valve when switching the flow path for delivering the grout material; It is a perspective view which shows an example of a structure of the injection pipe used for the construction system of this invention. FIG. 10 is a diagram showing flow rate variation in dynamic injection of the present invention; It is a schematic diagram which shows the position which performed the injection|pouring test of a grout material. It is a figure which shows the structure of the ground which performed the injection|pouring test of a grout material. FIG. 4 is a diagram showing the flow up to injecting grout material using the dynamic injection of the present invention; (a) A diagram showing pressure change of the grout material in the first packer when dynamic injection is performed, (b) A diagram showing pressure change of the grout material in the second packer when dynamic injection is performed. FIG. 5 is a diagram showing changes in pressure of grout material and changes in flow rate of grout material in the first packer when dynamic injection is performed; It is a figure which shows the flow until it statically injects a grout material. FIG. 5 is a diagram showing changes in grout material flow rate and pressure when static injection is performed. It is a figure which shows the ground strength of the injection|pouring position vicinity. (a) A diagram showing changes in the viscosity of the grout material, (b) is an enlarged diagram of 500 to 1000 seconds in (a).

The present embodiment will be described below with reference to the drawings.
As shown in FIG. 1, a construction system 10 for injecting a chemical solution has mixers 15 and 16, an injection pump 17, a flow/pressure detector 18, a switching valve 19, an injection pipe 20, a recording device 21, and a management device 22. The construction system 10 mixes two mixed liquids that become a chemical solution (hereinafter, grout material) by mixing while sending them by an injection pump 17, and alternately places the mixed grout material on a plurality of positions of the target ground. It is an injection system. In addition, the multiple positions of the ground may be multiple positions at the same position on the ground surface and different depths to which the grout material is injected, or multiple positions on the ground surface with the same depth or A plurality of different positions may be used. In FIG. 1, the signal transmission path is indicated by a two-dot chain line, and the liquid mixture delivery path is indicated by a solid line. Note that FIG. 1 shows an example of a construction system, but a chemical injector for realizing the construction system shown in FIG. 1 may be used.

The mixers 15 and 16 are devices for stirring either one of the two mixed liquids to prevent separation of the mixed liquids. Here, the liquid mixture stirred by the mixer 15 is called liquid A, and the liquid mixture stirred by the mixer 16 is called liquid B. In addition, A liquid and B liquid which are mixed liquids are mentioned later.

The injection pump 17 alternately delivers the A liquid and the B liquid mixed in the mixers 15 and 16 toward the switching valve 19 . The infusion pump 17 may be, for example, a two-component equal volume pump. As the injection pump 17, it is possible to use two injection pumps having the same mixed liquid delivery amount (discharge amount) instead of the two-liquid equivalent pump. , it is necessary to adjust the delivery timing of the mixture in each injection pump. Therefore, in this embodiment, by using a two-liquid equivalent pump as the injection pump 17, the same amount of mixed liquid is alternately delivered without adjusting the delivery timing of the mixed liquid (liquid A and liquid B). becomes possible. The infusion pump 17 is driven and controlled by the management device 22 .

As shown in FIGS. 2 and 3, the infusion pump 17, which is a two-fluid equal-volume pump, has two delivery sections 25, 26, a drive motor 27 and a drive section 28. As shown in FIG. Hereinafter, of the two delivery portions 25 and 26, the delivery portion for delivering the A liquid is referred to as the A liquid delivery portion 25, and the delivery portion for delivering the B liquid is referred to as the B liquid delivery portion .

The A liquid delivery part 25 has an injection port 31 , a delivery port 32 , an air chamber 33 and a main body 34 . The injection port 31 connects a hose 35 (see FIG. 1) extending from the mixer 15 . Also, the delivery port 32 connects a hose 36 (see FIG. 1) installed toward the flow rate/pressure detection device 18 .

The air chamber 33 stores part of the liquid A sent out from the storage space 34a when the plunger 51, which will be described later, moves toward the storage space 34a of the main body 34. As shown in FIG. Further, the air chamber 33 sends out the stored liquid A toward the delivery port 32 when the plunger 51 moves away from the storage space 34a. By providing the air chamber 33, it is possible to prevent pulsation from being superimposed on the delivery pressure or delivery speed of the liquid A to be delivered.

Reference numeral 37 is a valve for opening and closing the air chamber 33 . Valve 37 is a ball valve as an example. The valve 37 switches between a closed state in which the interior of the air chamber 33 and the flow path 34c are blocked, and an open state in which the interior of the air chamber 33 and the flow path 34c are communicated. When the valve 37 is closed, the function (action) of the air chamber 33 is disabled. Here, reference numeral 37a denotes a lever that switches the valve 37 between a closed state and an open state by an operator's operation, and switches the valve 37 state by an operator's operation of the lever 33a. Although the opening and closing of the valve 37 is switched by the operator's operation of the lever 37a, the opening and closing of the valve 37 may be switched automatically. In addition to closing the valve 37, the air chamber 33 can be removed as a method of disabling the function of the air chamber 33. FIG.

The main body 34 has a reservoir space 34 a , a channel 34 b connecting the injection port 31 and the reservoir space 34 a , and a channel 34 c connecting the reservoir space 34 a and the delivery port 32 . That is, the grout material flows in the order of the channel 34b, the storage space 34a and the channel 34c. Moreover, the flow path 34b and the flow path 34c are provided with check valves 38 and 39, respectively.

The B liquid delivery part 26 has an injection port 41 , a delivery port 42 , an air chamber 43 and a main body 44 similarly to the A liquid delivery part 25 . The injection port 41 connects a hose 45 extending from the mixer 16 (see FIG. 1). Also, the delivery port 42 connects a hose 46 (see FIG. 1) installed toward the flow rate/pressure detection device 18 .

The air chamber 43 stores part of the B liquid sent out from the storage space 44a when the plunger 52, which will be described later, moves toward the storage space 44a of the main body 44. As shown in FIG. Further, the air chamber 43 sends out the B liquid stored in the storage space 44a toward the delivery port 42 when the plunger 52 moves away from the storage space 44a. By providing the air chamber 43, it is possible to prevent pulsation from being superimposed on the delivery pressure or delivery speed of the B liquid to be delivered.

Reference numeral 47 is a valve for opening and closing the air chamber 43 . Valve 47 is a ball valve as an example. The valve 47 switches between a closed state in which the interior of the air chamber 43 and the flow path 44c are blocked, and an open state in which the interior of the air chamber 43 and the flow path 44c are communicated. When the valve 47 is closed, the function (action) of the air chamber 43 is disabled. Here, reference numeral 47a denotes a lever that switches the valve 47 between a closed state and an open state by an operator's operation, and switches the valve 47 state by the operator's operation of the lever 47a. Although the opening and closing of the valve 47 is switched by the operator's operation of the lever 47a, the opening and closing of the valve 47 may be switched automatically. Moreover, as a method of disabling the function of the air chamber 43, it is also possible to remove the air chamber 43 in addition to closing the valve 47. FIG.

The main body 44 has a reservoir space 44a, a channel 44b connecting the injection port 41 and the reservoir space 44a, and a channel 44c connecting the reservoir space 44a and the delivery port . That is, the grout material flows in the order of the channel 44b, the storage space 44a and the channel 44c. The flow path 44b and the flow path 44c are provided with check valves 48 and 49, respectively.

As shown in FIGS. 3( a ) to 3 ( d ), the driving section 28 has plungers (pistons) 51 and 52 , motion conversion sections (connecting rods) 53 and 54 , a crankshaft 55 and a crankcase 56 . The plungers 51 , 52 are arranged in cylinders 57 , 58 provided in parallel with the crankcase 56 , and reciprocate within the cylinders 57 , 58 as the crankshaft 55 rotates.

The motion converters 53 and 54 reciprocate the plungers 51 and 52 when the crankshaft 55 rotates. One end of the motion converting portion 53 is rotatably supported by the plunger 51 with a pin, and the other end is rotatably supported by a crankpin 55 a of the crankshaft 55 . Similarly, the motion converter 54 has one end rotatably supported by the plunger 51 via a pin and the other end rotatably supported by the crankpin 55b of the crankshaft 55 . Here, in a plane orthogonal to the axial direction of the crankshaft 55, the crankpins 55a and 55b of the crankshaft 55 are eccentrically shifted from the center of rotation of the crankshaft 55 by a predetermined amount, and the crankpins 55a and 55b are eccentric. are spaced 180° apart.

In the crankcase 56 , the cylinder 57 communicates with the storage space 34 a of the main body 34 of the liquid A delivery section 25 via a passage 59 . In addition, the cylinder 58 communicates with the storage space 44a of the main body 44 of the B liquid delivery section 26 via the passage 60 .

It should be noted that diaphragms may be arranged in the above-described storage space 34a and storage space 44a, and the reciprocating plunger may cause the diaphragms to draw the liquid into the storage space or send out the liquid stored in the storage space.

Next, the operation of each part of the infusion pump 17 will be described. A case where the plunger 51 is located closest to the storage space 34a of the liquid A delivery portion 25 and the plunger 51 is located farthest from the storage space 34a of the liquid B delivery portion 26 will be described below as an example.

When the drive motor 27 is driven, the crankshaft 55 rotates in direction C in FIG. 3(a). One end of the motion converting portion 53 is pulled by the rotating crank pin 55a, and the plunger 51 moves in the direction D1 in FIG. 3(a). As the plunger 51 moves in the direction D1 in FIG. 3(a), the pressure in the space formed on the tip side (left side in the figure) of the plunger 51 and the cylinder 57 and the pressure in the storage space 34a communicating with the space decreases. As a result, the check valve 38 provided in the flow path 34b is opened, and the A liquid is sent into the storage space 34a through the flow path 34b. At this time, the A liquid stored inside the air chamber 33 is delivered toward the delivery port 32 . Since the check valve 39 provided in the flow path 34c is closed, the liquid A does not flow back toward the storage space 34a.

One end of the motion converting portion 53 is pulled by the rotating crank pin 55a, and the plunger 51 moves in the direction D1 in FIG. 3(a). One end is extruded. Therefore, the plunger 52 moves in the E1 direction in FIG. 3(b). The movement of the plunger in the E1 direction in FIG. 3B increases the pressure in the space formed on the tip side (left side in the figure) of the plunger 51 and the cylinder 57 and the storage space 34a communicating with the space. As a result, the check valve 49 provided in the channel 44c communicating with the delivery port 42 is opened, and the B liquid stored in the storage space 44a is delivered to the channel 44c. In addition, when the B liquid is sent out to the flow path 44 c, the B liquid is sent out toward the delivery port 42 and into the air chamber 43 . On the other hand, the check valve 48 provided in the flow path 44b is closed. Therefore, liquid B does not flow back from the storage space 44a to the channel 44b.

When the plunger 51 is moved to the farthest position from the storage space 34a by the rotation of the crankshaft 55, one end of the motion converting portion 53 is pushed out by the rotating crankpin 55a. By pushing out one end of the motion converting portion 53, the plunger 51 moves in the direction D2 in FIG. 3(c). When the plunger 51 moves in the direction D2 in FIG. 3(c), the pressure in the cylinder 57 and the storage space 34a increases. As a result, the check valve 39 provided in the channel 34c communicating with the delivery port 32 is opened, and the A liquid is delivered from the storage space 34a to the channel 34c. The liquid A sent out from the storage space 34 a is sent toward the delivery port 32 and also sent toward the inside of the air chamber 33 . On the other hand, the check valve 38 provided in the flow path 34b is closed. Therefore, the A liquid does not flow back from the storage space 34a to the channel 34b.

One end of the motion converting portion 53 is pushed out by the rotating crank pin 55a, while one end of the motion converting portion 54 is pulled by the rotating crank pin 55b. As a result, the plunger 52 moves in the E2 direction in FIG. 3(d). When the plunger 52 moves in the E2 direction in FIG. 3(d), the pressure inside the cylinder 58 and the storage space 44a decreases. Therefore, the check valve 48 provided in the flow path 44b communicating with the injection port 41 is opened, and the liquid B is introduced into the storage space 44a. At this time, the B liquid inserted inside the air chamber 43 is delivered to the delivery port 42 . Since the check valve 49 provided in the flow path 44c is closed, the liquid B does not flow back into the storage space 44a.

Therefore, when the valves 37 and 47 are opened, the liquid A delivery section 25 and the liquid B delivery section 26 are driven by the drive section 28 to deliver the mixed liquid by the reciprocating motion of the plungers 51 and 52, and the air chambers 33 and 43 alternately with the delivery of the mixed liquid stored in the . That is, addition (superimposition) of pulsation to the delivery pressure and delivery speed of the mixed liquid delivered from the A liquid delivery section 25 and the B liquid delivery section 26 is suppressed.

On the other hand, when the valves 37 and 47 are closed, only the mixed liquid is delivered by the reciprocating motion of the plungers 51 and 52 driven by the drive section 28 in the liquid A delivery section 25 and the liquid B delivery section 26 . As a result, pulsating pressure is applied (superimposed) when the delivery pressure of the liquid delivered from each delivery part is measured. That is, pulsation is added (superimposed) to the delivery pressure and delivery speed of the mixed liquid delivered from the A liquid delivery section 25 and the B liquid delivery section 26 .

In the method of injecting the grout material according to the present embodiment, the valves 37 and 47 are kept closed and the injection pump 17 is driven to inject the grout material in a state in which pulsation is superimposed on the injection pressure and injection speed of the grout material. inject.

Returning to FIG. 1 , the flow rate/pressure detection device 18 is arranged between the injection pump 17 and the switching valve 19 . Specifically, the flow rate/pressure detection device 18 is connected to the hose 61 after the hoses 36 and 46 connected to the delivery ports 32 and 42 of the injection pump 17 are merged. The flow rate/pressure detection device 18 acquires measurement data such as the flow rate pressure, instantaneous flow rate, and integrated flow rate of the grout material. Note that the acquired measurement data is stored in the recording device 21 .

The switching valve 19 is provided to switch the injection route of the grout material to either one of the two injection passages of the injection pipe 20 . The switching valve 19 is, for example, a ball valve. The switching valve 19 is connected to a hose 62 connected to the flow/pressure detector 18 . Further, the switching valve 19 has a hose 63 for delivering the grout material to the first packer 101 of the inner injection pipe of the injection pipe 20 and a hose for delivering the grout material to the second packer 102 of the inner injection pipe of the injection pipe 20. 64.

As shown in FIGS. 4 to 6 , the switching valve 19 has a valve body 71 and a ball valve 72 . The valve body 71 is T-shaped and has joints 71a, 71b, and 71c at its ends. Of these joint portions 71a, 71b, and 71c, the joint portion 71b and the joint portion 71c are arranged so that their axial directions are the same. Further, the joint portion 71a is arranged so as to be perpendicular to the axial direction of the joint portions 71b and 71c. A fitting portion 62a provided at one end of a hose 62 for feeding grout material is screwed to the joint portion 71a. A fitting portion 63a provided at one end of a hose 63 for feeding the grout material to the first packer 101 of the injection inner pipe 92 of the injection pipe 20 is screwed to the joint portion 71b. Further, a fitting portion 64a provided at one end of a hose 64 for feeding the grout material to the second packer of the injection inner pipe 92 of the injection pipe 20 is screwed to the joint portion 71c.

The ball valve 72 is arranged inside the valve body 71 . The ball valve 72 rotates in one direction, for example, every 180° around the valve shaft 75 by a drive unit (not shown). The ball valve 72 has a flow passage 76a extending toward the central portion from the lower end opposite to the top portion to which the valve shaft 75 is attached, and a flow passage extending perpendicular to the flow passage 76a. 76b has an L-shaped flow path 76 that communicates with the central portion of the ball valve 72. As shown in FIG. Further, the ball valve 72 has a relief channel 77 perpendicular to each of the channels 76a and 76b. The diameter of the escape channel 77 is set based on the injection pressure and injection speed of the grout material to be injected. The ball valve 72 is held inside the valve body 71 while being sandwiched between the valve seats 73 and 74 .

Here, when the fitting portion 62a provided in the hose 62 is screwed into the joint portion 71a, the flow path 76a of the L-shaped flow path 76 is always connected to the flow path (not shown) of the fitting portion 62a. A connected state is established. On the other hand, the channel 76b of the L-shaped channel 76 is the channel 81 of the fitting portion 63a screwed to the joint portion 71b, or the channel 81 of the fitting portion 64a screwed to the joint portion 71c. 82 in communication.

FIG. 6A shows, for example, a case where the flow path 76b of the L-shaped flow path 76 of the ball valve 72 is held in communication with the flow path 81 of the fitting portion 63a. In this state, the grout material sent inside the hose 62 is sent inside the hose 63 after passing through the L-shaped flow path 76 of the ball valve 72 . That is, in this state, the grout material is delivered to the first packer 101 of the injection inner pipe of the injection pipe 20 .

When switching the switching valve 19 to feed the grout material, the valve shaft 75 is rotated in the direction L1 in FIG. As shown in FIG. 6(b), when the valve shaft 75 is rotated, the ball valve 72 rotates in the direction of the arrow in FIG. 6(b). By rotating the ball valve 72 in the direction indicated by the arrow in FIG. , and the flow path 81 provided in the fitting portion 63 a of the hose 63 is blocked by the peripheral wall surface of the ball valve 72 .

When the ball valve 72 is further rotated, the release channel 77 of the ball valve 72 communicates with the channel 81 provided in the fitting portion 63a of the hose 63, as shown in FIG. 6(c). When the ball valve 72 is further rotated, as shown in FIG. 6(d), the state in which the relief flow path 77 and the flow path 81 provided in the fitting portion 63a of the hose 63 communicate with each other is released. When the ball valve 72 is rotated by 180°, the flow path 76b communicates with the flow path 82 provided in the fitting portion 64a of the hose 64, as shown in FIG. 6(e). Therefore, in this state, the grout material sent inside the hose 62 is sent inside the hose 64 after passing through the L-shaped flow path 76 of the ball valve 72 . That is, in this state, the grout material is delivered to the second packer 102 of the injection inner pipe 92 of the injection pipe 20 . The switching valve 19 switches the state of sending the grout material to the second packer 102 of the inner injection pipe 92 of the injection pipe 20 to the state of sending it to the first packer 101 of the inner injection pipe 92 of the injection pipe 20. In this case, after the flow path 76 b that constitutes the L-shaped flow path 76 is retracted from the state in which it communicates with the flow path 82 provided in the fitting portion 64 a of the hose 64 , the escape flow path 77 is engaged with the hose 64 . Communicates with the flow path 82 provided in the joining portion 64a, and forms an L-shaped flow path 76 after the release flow path 77 retreats from the state of communication with the flow path 82 provided in the fitting portion 64a of the hose 64. The flow path 76 b communicates with the flow path 81 provided in the fitting portion 63 a of the hose 63 .

Therefore, when the switching valve 19 is used to switch the grout material feeding channel, a state is created in which the switching source channel and the escape channel 77 are in communication with each other. As a result, it is possible to prevent excessive pressure from being applied to the grout material to be injected, and damage to the ball valve 72 can be prevented.

As shown in FIG. 7, the injection tube 20 has an outer injection tube 91 and an inner injection tube 92 . The injection outer tube 91 is, for example, a manchette tube used in the double packer construction method. The outer injection tube 91 is provided with discharge ports 95 at a predetermined interval (L1 in the drawing) at the lower end in the longitudinal direction. FIG. 7 shows, as an example, the case where the ejection ports 95 are provided at four positions in the longitudinal direction of the outer injection tube. The constant interval L1 described above is, for example, 600 mm. The discharge ports 95 are arranged on the outer peripheral surface of the injection outer tube 91 at intervals of, for example, 90 degrees. The ejection ports 95 provided at four locations in the longitudinal direction of the outer injection tube 91 are shielded by rubber sleeves 96 attached to the outer injection tube 91 . Although illustration is omitted, the rubber sleeve 96 is fixed at one end in the longitudinal direction of the outer injection tube with a binding band.

The rubber sleeve 96 is elastically deformed by the pressure received from the injected grout material, and the gap between the discharge port 95 and the open end of the rubber sleeve 96 (the end opposite to the end fixed by the binding band) creates a gap in By forming this gap, the grout material is radially discharged. In addition, the rubber sleeve 96 closes the discharge port 95 of the outer injection tube 91, so that it is pressed against the discharge port 95 against the pressure from the outside and is in close contact with the discharge port 95. prevent intrusion.

The injection inner tube 92 has a first packer 101, a second packer 102, and a connecting rod 103 connecting these packers. The first packer 101 includes an upper packer part 105 , a lower packer part 106 and a nozzle 107 . The upper packer portion 105 and the lower packer portion 106 are inflated by the air flowing from the air adapter 108 and come into contact with the inner wall surface of the outer injection tube 91 . The nozzle 107 has a plurality of discharge ports 109 on its outer peripheral surface and discharges the grout material supplied from the chemical solution adapter 110 . The chemical solution adapter 110 is connected to the hose 63, for example.

Similarly, the second packer 102 comprises an upper packer portion 111 , a lower packer portion 112 and a nozzle 113 . The upper packer portion 111 and the lower packer portion 112 swell due to the air flowing from the air adapter 108 and abut against the inner wall surface of the outer injection tube 91 . The nozzle 113 has a plurality of discharge ports 114 on its outer peripheral surface and discharges the grout material sent from the chemical solution adapter 115 . The chemical solution adapter 115 is connected to the hose 64, for example.

The connecting rod 103 is connected to the first packer 101 on the upper end side and connected to the second packer 102 on the lower end side. Although not shown, the connecting rod 103 includes a feed passage for feeding the grout material fed from the chemical solution adapter 115 toward the nozzle 113 of the second packer 102, and a feed passage for feeding air flowing in from the air adapter 108 to the second A feed passage for feeding air to each of the upper packer portion 105 and the lower packer portion 106 of the packer 102 is provided.

Next, the grout material used in this embodiment will be described. The grouting material is a non-Newtonian grouting material containing metal methacrylate, polyvalent metal salt compound, reducing agent, polymerization initiator, aggregate and water.

Examples of metal methacrylic acid salts include alkali metal salts such as lithium, sodium and potassium salts of (meth)acrylic acid; alkaline earth metal salts such as calcium and barium salts; magnesium salts, aluminum salts and zirconium salts; Salts and the like may be mentioned, and only one of these may be used alone, or two or more thereof may be used in combination. In this embodiment, the case of using magnesium acrylate with a concentration of 35% by mass will be described.

The polyvalent metal salt compound is a polyvalent metal salt compound other than the methacrylic acid metal salt, and a polyvalent metal salt compound having a valence of 2, 3 or more is used. Polyvalent metal salt compounds include, for example, divalent metals such as magnesium, calcium and barium. Examples of trivalent or higher metals include aluminum, zirconium, titanium and cerium. In addition, trivalent metal salt compounds are preferable from the viewpoint of easy control of the strength of the gel product. ), polyaluminum sulfate (basic aluminum sulfate), zirconium acetate, zirconium nitrate, zirconium chloride, zirconium lactate, zirconium carbonate, zirconium oxynitrate, zirconium oxyacetate, zirconium sulfate, zirconium salts such as zirconium oxysulfate, titanium chloride and cerium nitrate. As the polyvalent metal salt compound, one of these metal salts may be used alone, or two or more thereof may be used in combination. In addition, in the present invention, the case of using highly basic polyaluminum chloride (highly basic PAC) as the polyvalent metal salt compound will be described.

Reducing agents include thiosulfate compounds such as sodium thiosulfate and potassium thiosulfate, bisulfite compounds such as sodium bisulfite and potassium bisulfite, hypophosphite compounds such as sodium hyposulfite and potassium hyposulfite, sodium sulfite and Sulfite compounds such as potassium sulfite, hydroxymethanesulfinates such as sodium hydroxymethanesulfinate (Rongalite), ascorbic acid or salts thereof such as sodium ascorbate, erythorbic acid or salts thereof such as sodium erythorbate, ferrous salts, In addition to thiourea disulfide, copper sulfate, and amines such as diethanolamine, triethanolamine, hydrazine, hydroxylamine, dimethylaminopropionitrile, dimethylaminopropanol, piperazine and morpholine can be used. These reducing agents can be used singly or in combination of two or more. In the present invention, the case of using sodium thiosulfate as a reducing agent will be explained.

The polymerization initiator is added to polymerize the methacrylic acid metal salt, and various known polymerization initiators applicable to methacrylic acid can be used. For example, from the viewpoint of pot life, control of curing time from ground injection to curing (gelation), etc., azo initiators, inorganic peroxides such as peroxodisulfate, organic peroxides such as percarboxylic acids, hydroperoxides, etc. Peroxides and the like can be used. When inorganic peroxides and organic peroxides are used, a reducing agent can be used together as appropriate. In the present invention, the case of using t-amylhydroperoxide (TAH) as the polymerization initiator will be explained. The t-amyl hydroperoxide (TAH) used has a peroxide content of 85% by mass.

Aggregates are compounded to increase or reinforce the composition, and include cement, fly ash, diatomaceous earth, calcium carbonate, kaolin, clay, bentonite, perlite, vermiculite, blast furnace slag, gypsum, silica sand, pulp and carbon powder. powder and various fibers can be used. In addition, in the present invention, the case of using calcium chloride as an aggregate will be described.

The concentration of magnesium acrylate in the grout material having the above composition is set to 5.5% by mass. Also, the concentration of the high base PAC in the grout material having the above composition is set to 2.5% by mass. It should be noted that the grout material having the above composition is substantially neutral and has excellent permeability or durability.

In this embodiment, when preparing the grout material 400L having the above composition, the amounts of each substance mixed are as follows. 55 L magnesium acrylate, 0.85 kg sodium thiosulfate, 4.3 kg calcium chloride, 35 L high base PAC, 0.42 kg TAH and 305 L water. When injecting grout material into the ground, a mixed solution prepared by preparing 55 L of magnesium acrylate, 0.85 kg of sodium thiosulfate, 4.3 kg of calcium chloride and 140 L of water is used as liquid A, and 35 L of high base PAC and 0.42 kg of TAH are used. and 165 L of water were prepared to form a liquid B. In addition, the pH of the A liquid is pH=6.6, and the pH of the B liquid is pH=4.5.

As shown in FIG. 8, the method of injecting grout material according to the present invention is an injection method in which pulsation is superimposed (added) to the injection speed and injection pressure of the grout material during the injection process of inching injection in which injection and interruption are repeated. adopted. Hereinafter, the method of injecting the grout material according to the present invention will be described as being referred to as dynamic injection.

First, a flat soil tank test using dynamic injection and static injection was performed. In the flat soil tank test, silica sand No. 7 was used, and a model ground with a length of 50 cm, a width of 50 cm, and a thickness of 5 cm with a relative density of 60% was produced. The grout material was prepared from magnesium acrylate (AAMg), high base polyaluminum chloride, citric acid and sodium hydroxide and water. The concentration of magnesium acrylate in the grout material is 4% by weight, the concentration of overbased polyaluminum chloride is 2% by weight, the concentration of citric acid is 2.6% by weight, and the concentration of sodium hydroxide is 2.5% by weight.
Table 1 shows the contents of the flat soil tank test.

In Table 1, test numbers 1, 2, 5, and 7 are static injections, and test numbers 3, 4, 6, and 8 are dynamic injections. In addition, in these tests, the injection time of the grout material was set to 15 minutes or 30 minutes, and the injection amount of the grout material was set to 1500 mL as target values.

First, the injection time and injection rate when static injection is performed will be described.
Test No. 1 had a grout material injection time of 16 minutes, an injection amount of 1,270 mL, an average injection rate of 79.4 mL/min, and a gel time of 5 minutes. In Test No. 1, the injection speed was slow and the target injection amount could not be injected.
Test No. 5 had a grout material injection time of 29.3 minutes, an injection amount of 1,550 mL, an average injection rate of 52.9 mL/min, and a gel time of 5 minutes.
Test No. 2 had a grout material injection time of 16 minutes, an injection amount of 1,530 mL, an average injection rate of 95.6 mL/min, and a gel time of 30 minutes.
Test No. 7 had a grout material injection time of 30 minutes, an injection amount of 1,510 mL, an average injection rate of 50.3 mL/min, and a gel time of 47 minutes.

The injection time and injection rate when dynamic injection is performed will be described.
Test No. 3 had a grout material injection time of 16 minutes, an injection amount of 1,550 mL, an average injection speed of 96.9 mL/min, and a gel time of 4 minutes and 50 seconds. At this time, the period of injecting the grout material (inching period) was 1 minute, and the frequency of the pulsation to be superimposed was 5 Hz.
Test No. 6 had a grout material injection time of 29 minutes, an injection amount of 1,540 mL, an average injection rate of 53.1 mL/min, and a gel time of 5 minutes. At this time, the period of injecting the grout material (inching period) was 1 minute, and the frequency of the pulsation to be superimposed was 2.5 Hz.
Test No. 4 had a grout material injection time of 15 minutes, an injection amount of 1,560 mL, an average injection rate of 104 mL/min, and a gel time of 17 minutes. At this time, the period of injecting the grout material (inching period) was 1 minute, and the frequency of the pulsation to be superimposed was 5 Hz.
Test No. 8 had a grout material injection time of 30 minutes, an injection amount of 1,510 mL, an average injection rate of 50.3 mL/min, and a gel time of 47 minutes. At this time, the period of injecting the grout material (inching period) was 1 minute, and the frequency of the pulsation to be superimposed was 2.5 Hz.

First, Table 2 shows a comparison between Test No. 1 and Test No. 3 in which the gel time is short and the injection speed is fast. The measured area in the table is the area of the improved body actually formed in the model ground by the above test. The improved area is the area of the improved product calculated from the injection amount. The unconfined compressive strength was measured for each of the improved bodies formed in the model ground divided into a predetermined area.

In Test No. 1, the measured area/improved area was 0.7, and the unconfined compressive strength was 147, 183, 193 kN/m ² . On the other hand, in Test No. 3, the measured area/improved area was 0.86, and the unconfined compressive strength was 49, 73, and 73 kN/m ² .

That is, the test number 3 obtained the result that the measured area/improved area was improved by about 20% compared to the test number 1. On the other hand, it was found that the unconfined compressive strength decreased.
Next, Table 3 shows a comparison between Test No. 2 and Test No. 4 in which the gel time is long and the injection speed is fast.

In Test No. 2, the measured area/improved area was 1.05, and the unconfined compressive strength was 62,120,126 kN/m ² . On the other hand, in Test No. 4, the measured area/improved area was 1.11, and the unconfined compressive strength was 90, 111, and 120 kN/m ² .

That is, it was found that Test No. 4 improved the measured area/improved area by about 6% as compared with Test No. 2. As for the unconfined compressive strength, similar results were obtained in Test No. 2 and Test No. 4 except for a part.

Next, Table 4 shows a comparison between Test No. 5 and Test No. 6 in which the gel time is short and the injection speed is slow.

In Test No. 5, the measured area/improved area was 0.45 and the unconfined compressive strength was 110,137 kN/m ² . On the other hand, in Test No. 6, the measured area/improved area was 0.48, and the unconfined compressive strength was 108,133 kN/m ² .

That is, it was found that Test No. 6 improved the measured area/improved area by about 7% compared to Test No. 5. As for the unconfined compressive strength, test numbers 5 and 6 gave the same results.

Finally, Table 5 shows a comparison between Test No. 7 and Test No. 8 in which the gel time is long and the injection speed is slow.

In Test No. 7, the measured area/improved area was 0.77, and the unconfined compressive strength was 142, 145, 146 kN/m ² . On the other hand, in Test No. 8, the measured area/improved area was 0.78, and the unconfined compressive strength was 138,185 kN/m ² .

That is, it was found that Test No. 8 improved the measured area/improved area by about 1% compared to Test No. 7. As for the unconfined compressive strength, test numbers 7 and 8 gave the same results.

Considering the above comparison results, it was found that the dynamic grouting of the present invention penetrated the grout material in a wider area and obtained a uniaxial compressive strength equivalent to that of the static grouting.

In addition, in Test No. 2 described above, although the concentration of the grout material is the same, the uniaxial compressive strength of the improved body varies. Therefore, the amount of organic carbon (wt%) of the modified body was measured to check whether the grout material was evenly injected. Also, in order to investigate whether the reaction of magnesium acrylate (AAMg) contained in the grout material has progressed, the residual AAMg amount (wt %) in the improved material was measured. The amount of organic carbon and the amount of residual AAMg in the improved product were measured using a sand gel uniformly formed by a mold as a comparison object. Specimens A, B, and C in Table 6 shown below are obtained by dividing the improved specimens formed by the above-described flat earth tank test.

The sand gel uniformly produced by the mold had a uniaxial compressive strength of 160 kN/m ² . At this time, the amount of organic carbon in the improved product was 2.1 wt%, and the amount of residual AAMg in the improved product was 0.27 wt% in terms of carbon.

As described above, the unconfined compressive strengths in Test No. 2 were 126, 120 and 62 kN/ ^m2 . For example, in test specimen A with a uniaxial compressive strength of 126 kN/ ^m2 , the amount of organic carbon in the improved body was 2.0 wt%, and the amount of residual AAMg in the improved body was 0.50 wt% in terms of carbon. . In addition, in the test specimen B having a uniaxial compressive strength of 120 kN/ ^m2 , the amount of organic carbon in the improved body was 2.0 wt%, and the amount of residual AAMg in the improved body was 0.56 wt% in terms of carbon. . Furthermore, in the test specimen C with a uniaxial compressive strength of 120 kN/ ^m2 , the amount of organic carbon in the improved body was 2.0 wt%, and the amount of residual AAMg in the improved body was 0.79 wt% in terms of carbon. . The amount of organic carbon contained in the specimen C is sufficiently contained at 90% or more of the amount of organic carbon contained in the sand gel prepared by the mold. On the other hand, the amount of residual AAMg in the improved specimen is higher than that in other test specimens. In other words, in the specimen C, the grout material was sufficiently injected, but the reaction in the grout material did not proceed sufficiently. Although the measurement results are omitted, similar results were obtained for Test No. 3 as well. Since the reaction of magnesium acrylate progresses with the passage of time, the unconfined compressive strength corresponds to the amount of organic carbon if the number of curing days is appropriate. Therefore, it is inferred that the final unconfined compressive strength is the same between static and dynamic injection.

Hereinafter, as shown in FIG. 9, a pouring test using dynamic pouring according to the present invention was conducted in the vicinity of the ground on which foundation concrete 120 was placed. For comparison, an injection test using a general static injection method and an injection test using a static injection method for a region below the base concrete were conducted. In addition, the positions where the dynamic injection of the present invention is performed are positions P ₁ , P ₂ , P ₃ and P ₄ in FIG. 9 . Also, the static injections are performed at four positions P ₅ , P ₆ , P ₇ and P ₈ in FIG. 9 . Furthermore, there are two static injections of the base concrete 120 downward, at positions _P9 and _P10 in FIG. In the static injection downward of the foundation concrete 120, the grout material is injected after drilling obliquely downward. In these tests, it is assumed that a spherical improved body with a radius of 1.25 m is generated centered at a position that is 2800 mm deep from the ground surface.

The ground on which the above tests were conducted is as follows. As shown in FIG. 10, the ground consists of, from the ground surface, an embankment (gravel) layer (symbol S1 in FIG. 10), an embankment (gravel-mixed sand) layer (symbol S2 in FIG. 10), an embankment (silt-mixed sand) layer ( S3 in FIG. 10), gravel-mixed sand layer (S4 in FIG. 10), sand layer (S5 in FIG. 10), sandy silt layer (S6 in FIG. 10), and silt layer (S7 in FIG. 10). be done. When the ground surface is set to 0, the embankment (gravel) layer has a depth of 0 to 0.9 m, the embankment (gravel mixed sand) layer has a depth of 0.9 to 2 m, and the embankment (gravel mixed sand) layer has a depth of 0.9 to 2 m. This layer is formed at a depth of 2 to 2.35 m. The gravel-mixed sand layer is formed at a depth of 2.35 to 3 m, the sand layer at a depth of 3 to 4.1 m, and the sandy silt layer at a depth of 4.1 to 4.8 m. Furthermore, the silt layer is a layer formed at a depth of 4.8m to 6.5m. For example, the engineering property N value of the ground determined by the standard penetration test for each layer is 7 to 10 for the embankment (sand mixed with gravel) layer, 7 for the embankment layer, and 5 to 9 for the sand layer mixed with gravel. Also, the sand layer is 1. In the standard penetration test for the sandy silt layer and the silt layer, the N value was set to 0 because the striking hammer sank by itself.

The soil properties at a depth of 1.5 to 2.3 m and the soil properties at a depth of 3.0 to 3.9 where the grout material is injected are as follows.

The dynamic injection flow of the present invention implemented for positions P ₁ , P ₂ , P ₃ and P ₄ will now be described with reference to FIG. As shown in FIG. 11(a), a casing pipe 125 installed in a drilling machine and a rod 127 having a drilling head 126 at its tip are rotated to drill vertically to a predetermined depth. After that, the rod 127 is pulled up. After pulling up the rod 127, the injection pipe 128 is inserted into the inside of the casing pipe 125 to fill the inside of the casing pipe 125 with a gel sealing material 129 (see FIG. 11(b)). After filling the inside of the casing pipe 125 with the sealing material 129, the injection outer tube 91 is inserted into the inside of the casing pipe 125 (see FIG. 11(c)). Then, the casing pipe 125 is pulled out and cured until the sealing material hardens (see FIG. 11(d)). Here, the position of the ejection port 95 formed in the outer injection tube 91 is held so as to be located at a depth of 2500 mm and a depth of 3100 mm from the ground surface. As shown in FIG. 11(e), after inserting the inner injection pipe 92 into the outer injection pipe 91, the injection pump 17 is operated to inject the grout material. When grouting is performed dynamically, grouting is alternately injected to each of the two injection positions while switching the grouting injection route by means of the switching valve 19 . 12(a) shows an example of pressure change of the grout material delivered from the first packer 101, and FIG. 12(b) shows an example of pressure change of the grout material delivered from the second packer 102. As shown in FIG. Moreover, FIG. 13 shows an example of pressure change and flow rate change of the grout material when dynamic injection is performed.

The static injection procedure performed for positions P ₅ , P ₆ , P ₇ and P ₈ will now be described. The procedure of static injection is the same as the procedure of the dynamic method in FIG. 11, the step of drilling (see FIG. 14(a)) and the step of filling the sealing material (see FIG. 14(b)). is carried out. After filling the inside of the casing pipe 125 with the sealing material 129, the injection outer tube 130 is inserted inside the casing pipe 125 (see FIG. 14(c)). Then, the casing pipe 125 is pulled out and cured until the sealing material 129 hardens (see FIG. 14(d)). At this time, the outer injection tube 130 is held so that the injection hole 131 of the outer injection tube 130 is positioned at a depth of 2800 mm. Then, as shown in FIG. 14( e ), the grout material is injected into the ground by static injection by inserting the injection inner pipe 132 . Reference numerals 133 and 134 are packers, and reference numeral 135 is a discharge port. FIG. 15 shows an example of pressure change and flow rate change of grout material when static injection is performed.

It should be noted that the difference between the static injections performed for positions P ₉ and P ₁₀ and the static injections performed for positions P ₅ , P ₆ , P ₇ and P ₈ is that the ground The difference is that the hole is drilled at an angle of 30° with respect to the surface.

Table 7 below shows the details of the injection test described above. In the injection test described above, the injection amount (planned injection amount) of the grout material injected at each position was set to 2,000L. Moreover, the injection time of the grout material was set to 200 minutes, and the injection speed of the grout material was set to 10 L/min.

In addition, when the grout material was injected into the ₁₀ locations from the position P1 to the position _P10 described above, the groundwater level fluctuation was not observed in the observation wells provided at the positions _P11 and _P12 shown in FIG. I didn't. Also, no change in water temperature or pH was observed due to the injection of the grout material. In addition, although not shown in the drawings, for the ground surface subjected to dynamic injection and static injection, the displacement in the direction perpendicular to the ground surface and in the direction horizontal to the ground surface was as small as ±2 mm. The variation is within the margin of error.

The SDS test was performed after a sufficient curing period for strength development for the vicinity of the ground where dynamic injection and static injection were performed, and the N value, which is the ground strength, was obtained. The SDS test is a Swedish-type sounding test with a special test device installed, and estimates the ground strength by calculating the torque value after removing the influence of the circumferential friction acting on the rod. In addition, the ground strength N value is measured at positions 0.3m, 0.625m, 1.25m and _2.5m away from the position P2 where the grout material is injected for dynamic grouting. and Similarly, for the statically grouted ground, the measurement targets were positions 0.3 m, 0.625 m, 1.25 m and 2.5 m away from the position _P8 where the grout material was injected. As shown in FIG. 16, in static injection, it was found that the N value increased at a deeper depth (0.5 m) than the depth (2.8 m) at which the grout material was injected. On the other hand, in dynamic injection, the N value increases near the position of the first packer 101 (2.5 to 3.0 m), and the N value increases near the position of the second packer 102 (3.1 m). not increased. In addition, when comparing the N value of the ground after static injection and the N value of the ground after dynamic injection, it was found that the N value was higher with dynamic injection than with static injection.

Also, the improved product was confirmed for the range a1 and the range a2 shown in FIG. The excavation depth in these ranges a1 and a2 is 2.5 to 3 m. Here, the area a1 is the area where the grout material is statically injected, and the area a2 is the area where the grout material is dynamically injected. For example, if the area a1 is excavated, a large number of rock masses and debris are mixed at the depth where the improved body is assumed to be formed (hereinafter referred to as the planned depth). In addition, it was confirmed that the grout material escaped into the gap and that no high-strength improved material was formed at the planned depth of excavation.

On the other hand, when the area a2 was excavated, it was confirmed that the injected grout hardened to a depth of about 30 to 50 cm deeper than the planned depth, producing an improved body. In addition, the range of the produced improved body was about 1.5 m. According to this, it was found that by injecting grout material into soft ground by dynamic injection according to the present invention, an improved body can be produced in the ground.

For example, FIG. 17A shows changes in the viscosity of the grout material when the grout material is injected with the shear rate Va set to Va=1 (1/s) and the shear rate Vb set to Vb=10 (1/s). , FIG. 17(b) shows the details of 500 to 1300 seconds in FIG. 17(a). For example, when the shear rate is low, the time required to reach the target clay is shorter than when the shear rate is high, and the time to start thickening is also shorter. In other words, when the shear rate is small, the gel generated by the polymerization of the metal methacrylate is not broken, and as a result, the viscosity of the grout material increases. On the other hand, when the shear rate is high, the gel is destroyed and the grout material does not thicken until the gel is formed. Therefore, it can be seen that by using the dynamic injection of the present invention, the thickening of the grout material is delayed, and the grout material spreads widely in the ground even if the ground is soft.

Therefore, by the dynamic injection of the present invention, even when a grout material that is a non-Newtonian fluid other than a cement-based grout material is used, it can be applied to a wide range of soft ground such as sandy soil layers and buried soil layers. It was found that grouting material could be injected and a good improved body could be created in the ground.

DESCRIPTION OF SYMBOLS 10... Construction system, 17... Injection pump, 19... Switching valve, 33, 43... Air chamber, 37, 47... Valve, 72... Ball valve, 76... L-shaped channel, 77... Escape channel

Claims (7)

a delivery means for delivering the chemical solution in a state in which pulsation is added to the delivery speed or delivery pressure of the chemical solution for improving the ground;
a switching member that repeats injection and interruption of the chemical solution to each of a plurality of positions of the ground by switching a flow path of the chemical solution delivered by the delivery means a plurality of times;
has
The chemical liquid includes a first chemical liquid and a second chemical liquid that become a grout material when mixed,
The sending means is
It is connected to a first flow path for sending out the first chemical liquid and a second flow path for sending out the second chemical liquid,
A pulsation is added to the delivery speed or the delivery pressure of each of the first chemical solution and the second chemical solution, and the first chemical solution is alternately delivered to the first channel and the second chemical solution is delivered to the second channel, respectively. configured as
The flow path is a flow path obtained by joining the first flow path and the second flow path.
A dynamic injection device characterized by: The dynamic injection device of claim 1, wherein
The sending means is
an air chamber provided corresponding to each of the first flow path and the second flow path and preventing addition of pulsation to the delivery speed or delivery pressure of the first chemical solution or the second chemical solution; and disabling means for disabling operation;
A dynamic infusion device, characterized in that it is an infusion pump comprising: A dynamic injection device according to claim 2, wherein
The disabling means is a valve that opens and closes between the first flow path and the second flow path, and the air chambers corresponding to the first flow path and the second flow path, respectively. A dynamic injection device characterized by: A dynamic injection device according to any one of claims 1 to 3, wherein
The switching member is
a main body having an inlet into which the drug solution is sent, and a plurality of delivery ports provided corresponding to the plurality of positions and delivering the drug solution flowing in from the inlet;
a delivery path disposed inside the main body and communicating with the delivery port; and a delivery path communicating with any one of the plurality of delivery ports and delivering the sent chemical solution to one of the plurality of delivery ports. A ball valve having a chemical liquid flow path consisting of
A dynamic injection device, characterized in that it is a valve comprising: A dynamic injection device according to claim 4, wherein
The ball valve communicates with the chemical solution channel and communicates with a delivery port through which the chemical solution is delivered when the ball valve rotates in one direction, thereby adding to the chemical solution sent into the chemical solution channel. A dynamic injection device, characterized in that it has a relief channel that reduces the pressure applied. A dynamic injection device according to any one of claims 1 to 5, wherein
The dynamic grouting device , wherein the delivery means delivers the chemical liquid that becomes the non-Newtonian grout material . A dynamic injection construction method, wherein a chemical solution is simultaneously injected into a plurality of injection positions in the ground using the dynamic injection device according to any one of claims 1 to 5.

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