JP4392774B2 - Injection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an injection device that injects a chemical solution for ground improvement into the ground, and more particularly to an injection device of a type that adds pulsation to a chemical solution to be injected.
[0002]
[Prior art]
Examples of the injection method for injecting such a chemical solution while adding pulsation include, for example, JP-A-9-78564, JP-A-7-317052, JP-A-10-114938, JP-A-2000-27171, etc. Is disclosed.
[0003]
In the conventional chemical injection method, the frequency of pulsation is often less than 30 Hz. However, in the research conducted by the inventors, the pulsation with a frequency of less than 30 Hz is not much different from the case of injecting a chemical with static pressure, and the effect of adding the pulsation is poor.
On the other hand, high-frequency vibration is very damped.
Therefore, it has been difficult to generate a pulsation that sufficiently exerts the effect of adding pulsation and hardly attenuates and disappears.
Furthermore, even if an ultrasonic wave was added to the chemical solution, it was attenuated and disappeared before being ejected from the injection nozzle, so that no effect could be achieved.
[0004]
In addition, for each construction ground, there is a range of amplitude values of injection pressure fluctuations that can be injected most effectively, and such amplitude value ranges are obtained by various investigations performed prior to construction.
However, at present, it has not been performed to control the amplitude of the injection pressure to be within the range of the amplitude value found in the preliminary survey. In other words, the current injection method does not effectively use the preliminary survey results.
[0005]
In addition to this, in the conventional injection method, piping for conveying a chemical solution is often formed of a flexible material, and there is a problem that pulsation is attenuated due to expansion and restoration of the piping itself.
[0006]
[Problems to be solved by the invention]
The present invention has been proposed in view of the various problems of the prior art as described above, and can generate a pulsation that exhibits a sufficient effect of adding pulsation and that is difficult to attenuate and disappear. The purpose of the present invention is to provide an injection device that can fully utilize the results of the preliminary investigation and does not attenuate various vibrations and has high injection efficiency.
[0007]
[Means for Solving the Problems]
According to the present invention, in the injection apparatus for inserting the rod 40 having the chemical solution injection monitor 42 at the tip into the boring hole H drilled in the ground G to be improved and injecting the chemical solution for ground improvement from the chemical solution injection monitor 42, The ground improvement chemical storage tank 12 on the ground side, the pump 16 for supplying the ground improvement chemical stored in the storage tank 12, the pipe 14 connecting the pump 16 and the rod 40, and the pipe 14 A pressure source 26 that causes pulsation in the ground improvement chemical solution flowing through the accumulator 18, an accumulator 18 connected to a region downstream of the pump (16) in the pipe 14, and a pressure provided in the chemical solution injection monitor 42 The sensor 44 measures the pressure amplitude and transmits a control signal to the pressure source 26 of the accumulator 18 to control the pulsation pressure amplitude generated in the accumulator 18. The control means 20 measures the pressure amplitude at which the ground improvement chemical solution is injected into the ground G with the pressure sensor 44, and compares it with the range of the injection pressure amplitude value stored in the storage block 46. When the pressure amplitude is larger than the predetermined pressure amplitude, the amplitude on the accumulator 18 side is decreased. When the pressure is appropriate, the amplitude is maintained. When the pressure amplitude is smaller, the accumulator 18 side amplitude is increased.
[0008]
According to the present invention having such a configuration, the effect of adding pulsation is sufficiently exerted by causing pulsation to flow in the chemical solution flowing through the pipe by the pulsation generating means, and it is difficult to attenuate or disappear. Pulsations, for example pulsations having a frequency of 100 Hz-120 Hz, can be generated.
[0009]
In addition, by measuring the pressure amplitude of the chemical injection pressure into the ground and comparing it with a predetermined pressure amplitude determined in advance, the pressure amplitude of the pulsation generated in the chemical by the pulsation generating means is controlled, It is possible to drastically improve the chemical injection efficiency by fully utilizing the results of various investigations conducted prior to the injection method.
[0010]
Here, it is preferable that the pipe is made of a highly rigid material. This is because it is possible to prevent the pulsation from being absorbed by the expansion and restoration of the piping itself.
[0011]
Further, according to the present invention, the ultrasonic injection means 50 is provided in the chemical injection monitor 42.
[0012]
Here, the ultrasonic vibration is preferably about 10 kHz to 40 kHz. In particular, about 20 kHz is suitable.
[0013]
As a result of adding ultrasonic vibration to the injected chemical solution, the particles of the soil move, the apparent viscosity coefficient decreases, the chemical solution easily enters the soil, and the chemical solution is efficiently injected.
Further, since the ultrasonic monitor is provided in the injection monitor, the distance from the generation source of the ultrasonic vibration to the location where the ultrasonic wave is to be added becomes very short, and the ultrasonic wave is hardly attenuated. Therefore, sufficient ultrasonic vibration is added when the chemical solution is injected.
[0015]
According to the present invention having such a configuration, it is possible to achieve all the operational effects of the above-described inventions. That is, it is possible to generate a pulsation that exhibits a sufficient effect of adding a pulsation and hardly attenuates and disappears, for example, a pulsation having a frequency of 100 Hz to 120 Hz.
And the chemical | medical solution is inject | poured by the pressure amplitude of optimal injection | pouring pressure fully utilizing the result of the various investigations performed before an injection | pouring construction method, Therefore Injection efficiency can be improved dramatically.
Furthermore, by applying ultrasonic vibration, the particles of the soil are moved, the apparent viscosity coefficient is lowered, the chemical liquid can easily enter the soil, and the chemical liquid can be injected efficiently.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. In the accompanying drawings, similar members are denoted by the same reference numerals.
[0017]
FIG. 1 shows a first embodiment of the present invention.
In the ground G to be ground improved, a bore hole H is drilled. And the apparatus installed in the ground side is shown with the code | symbol 10 in FIG.
[0018]
As equipment to be installed on the ground side, a ground improvement chemical solution (including various grout materials) storage tank 12 and a ground improvement chemical solution stored in the tank 12 are supplied to a chemical solution injection monitor 42 described later. , A pump 16 for adding a head necessary to flow through the pipe 14 with respect to the chemical liquid, an accumulator 18 which is a pulse generating means for causing pulsation in the chemical liquid flowing through the pipe 14, and a control means There are 20 mags.
[0019]
Here, the pump 16 is driven by a motor 22, and a pressure sensor 24 is provided on the immediate downstream side (rear flow side) thereof.
The accumulator 18 is configured so as to cause pulsation in the chemical liquid flowing through the pipe 14 by a pressure source (a commercially available device having a known structure, which can be applied as long as it functions as a pressure generator). And a pressure sensor 28 is provided. A pressure sensor 30 is also provided on the downstream side (rear stream side) of the accumulator 18.
[0020]
The pipe 14 is made of a highly rigid material pipe. Since the piping 14 has high rigidity, unlike the case where the chemical solution is supplied by a tube made of a flexible material, the pulsation generated in the accumulator 18 and propagated in the chemical solution is attenuated by the expansion and restoration of the piping 14 itself. Is prevented.
[0021]
In the equipment 10 installed on the ground, reference numeral 32 denotes a relief valve interposed in the return pipe 14-1, reference numeral 34 denotes a variable orifice interposed in the return pipe 14-2, and reference numeral 36 denotes a pipe. 14 is a bell mouth provided at the end of the tank 12 side, and 38 is a check valve.
[0022]
The chemical solution for ground improvement stored in the tank 12 is added with a head by a pump 16 and flows through the pipe 14, and through a flow path (not shown) in the rod 40 inserted into the boring hole H, It penetrates into the ground from a monitor 42 (not shown) at the tip of the rod 40.
In FIG. 1, a state in which the chemical liquid is injected from the monitor 42 is indicated by an arrow A.
[0023]
In the embodiment of FIG. 1, the “pulsation in the chemical flowing through the pipe 14” is set to 100 Hz, for example.
In the pulsation with a frequency of less than 100 Hz, there is no great difference from the injection method that does not give pulsation to the chemical solution, and the merit by giving the pressure amplitude to the chemical solution cannot be fully enjoyed. On the other hand, if the frequency is too high, the (high-frequency) pulsation is likely to be attenuated, so that the pulsation is attenuated and disappears before reaching the monitor 42.
[0024]
Here, in the embodiment of FIG. 1, by combining the accumulator 18 and the pressure sensor 30 immediately downstream thereof, it is possible to generate a pulsation having an abnormal frequency of 100 Hz that could not be generated by the prior art.
[0025]
The monitor 42 is provided with a pressure sensor 44, and the pressure sensor 44 measures the amplitude (pressure amplitude) of the injection pressure when the chemical solution is injected (arrow A).
The pressure amplitude in the chemical solution injection measured by the pressure sensor 44 is supplied to the control means 20 by the signal transmission line CL-1, and the amplitude of the pulsation in the chemical solution flowing through the pipe 14 generated by the accumulator 18 is controlled by the pressure amplitude. Is done.
[0026]
Although not explained in detail, the optimum pressure amplitude range for the chemical solution injection in the ground to be improved has been obtained in advance by various investigations conducted prior to the ground improvement method (including the injection method). Therefore, if the amplitude of the pulsation generated in the accumulator 18 is controlled and the pressure amplitude of the injection pressure is adjusted to an optimum range, the chemical injection efficiency is drastically improved.
[0027]
Such control will be described with reference to FIGS.
The pump 24 is driven by the motor 22 and the chemical solution in the tank 12 is injected into the ground G from the injection nozzle (not shown) of the monitor 42 (arrow A), and the accumulator 18 causes pulsation in the chemical solution. Then, the pressure at which the chemical solution is injected into the ground G varies with a constant amplitude. This pressure fluctuation or pressure amplitude (measured pressure amplitude) is measured by the pressure sensor 44 (FIG. 2: step S1).
[0028]
Here, the optimum pressure amplitude range for the chemical solution injection in the ground G has already been obtained by the investigation conducted prior to the injection method, and the range of the injection pressure amplitude value (predetermined injection pressure amplitude) is the control means 20. Are stored in the storage block 46. If the value of the pressure amplitude of the injection pressure (measured pressure amplitude) is measured in step S1, it is compared with a predetermined injection pressure amplitude (a range of pressure amplitude optimal for chemical injection in the ground G) (step S2). .
[0029]
When the measured pressure amplitude is larger than the predetermined pressure amplitude (“large amplitude” in step S2), the accumulator 18 passes from the control means 20 to the pressure source 26 of the accumulator 18 via the signal transmission line CL-2. A control signal having a content for reducing the pressure amplitude of the generated pulsation is transmitted (step S3).
[0030]
On the other hand, when the measured pressure amplitude is smaller than the predetermined pressure amplitude (“small amplitude” in step S2), a control signal is transmitted that increases the pressure amplitude of the pulsation generated in the accumulator 18 (step S4). ).
In other words, when the amplitude of the injection pressure (measured pressure amplitude) measured by the underground pressure sensor 44 is out of the range of pressure amplitude (predetermined injection pressure amplitude) optimum for the chemical solution injection in the ground G. First, the pressure source 26 of the accumulator 18 is controlled to set the measured pressure amplitude to a predetermined injection pressure amplitude.
[0031]
If the measured pressure amplitude is a predetermined pressure amplitude (“appropriate” in step S2), the pressure amplitude of the pulsation generated in the accumulator 18 is maintained (step S5).
If a signal related to the control of the pressure amplitude of the pulsation generated in the accumulator 18 is transmitted (step S3, S4 or S5), the above-described control is repeated (step S6 is No loop) or the control is terminated (step S6 is completed). Yes).
[0032]
Next, a second embodiment of the present invention will be described with reference to FIG.
As in the first embodiment of FIG. 1, a bore G is drilled in the ground G to be ground improved.
[0033]
In FIG. 3, on the ground side, a chemical storage tank 12 for improving the ground, a pipe 14 for supplying a chemical improving liquid stored in the tank 12 to a chemical injection monitor 42 described later, and a chemical A pump 16 for adding a head necessary for flowing through the pipe 14 and a control means 20 are installed. The pump 16 is driven by a motor 22, and a pressure sensor 24 is provided immediately downstream (rear stream side).
[0034]
In the embodiment of FIG. 3, the pipe 14 may be made of a pipe made of a material having high rigidity or may be made of a pipe made of a flexible material.
In the embodiment of FIG. 1, an accumulator 18 and the like are provided to cause pulsation in the chemical solution. However, in the embodiment of FIG. 3, such a member is not used anymore and the pulsation that propagates in the chemical solution is attenuated. This is because there is no need to consider prevention.
[0035]
In FIG. 3, the return pipes 14-1 and 14-2, the relief valve 32, the variable orifice 34, the bell mouth 36, and the check valve 38 are the same as those in FIG. 1.
[0036]
In the embodiment of FIG. 3 as well, the chemical solution for ground improvement stored in the tank 12 is added with a head by the pump 16 and flows through the pipe 14, and the flow path in the rod 40 inserted in the bore hole H ( It penetrates into the ground from the monitor 42 (not shown) at the tip of the rod 40 (arrow A).
[0037]
Here, the chemical liquid injection monitor 42 at the tip of the rod 40 is provided with an ultrasonic wave generating means 50, and ultrasonic vibration (high frequency vibration or fine vibration) is applied to the chemical liquid injected from a nozzle (not shown) of the monitor 42. For example, high frequency vibration of 10-40 kHz, more preferably 20 kHz is added.
As the ultrasonic wave generation means 50, a known and commercially available one (for example, a piezoelectric element type) may be applied, and there is no particular limitation as long as it can withstand the environment at the construction site of the injection method. 3 is a cable for supplying an alternating current to the piezoelectric element of the ultrasonic wave generation means 50, and is connected to a commercial power source (not shown) via the control means 20.
[0038]
As a result of adding ultrasonic vibration to the injected chemical solution, the particles of soil G move, the apparent viscosity coefficient decreases, and it becomes easier for the chemical solution for ground improvement such as grout to enter the soil G. Is done efficiently. In particular, when the ground G is a rock or the like, it becomes easy to inject a chemical into a crack or a crack in the rock, and the injection efficiency is improved.
[0039]
Here, although the ultrasonic wave is very easily attenuated as compared with the low-frequency pulsation, in the embodiment of FIG. 3, since the ultrasonic generation means 50 is provided in the injection monitor 42, the generation of the ultrasonic vibration is generated. The distance from the source (ultrasonic wave generation means 50) to the location where the ultrasonic wave is to be added is very short, and therefore the ultrasonic wave is hardly attenuated. Therefore, sufficient ultrasonic vibration is added at the time of chemical injection.
[0040]
Other configurations and operational effects of the embodiment shown in FIG. 3 are the same as those of the embodiment of FIG.
[0041]
FIG. 4 shows a third embodiment of the present invention. The third embodiment relates to a combination of the first embodiment shown in FIGS. 1 and 2 and the second embodiment shown in FIG.
[0042]
In FIG. 4, a bore G is drilled in the ground G to be ground improved.
On the ground side, a chemical storage tank 12 for improving the ground, a pipe 14 for supplying the chemical liquid for ground improvement stored in the tank 12 to the chemical injection monitor 42, and a pipe 14 for the chemical are provided. A pump 16 for adding a head necessary for flowing, an accumulator 18 which is a pulse generating means for causing pulsation in a chemical flowing through the pipe 14, a control means 20 and the like are installed.
[0043]
The pump 16 is driven by a motor 22 and a pressure sensor 24 is provided immediately downstream thereof.
The accumulator 18 is configured to cause pulsation in the chemical flowing through the pipe 14 by the pressure source 26, and includes a pressure sensor 28. A pressure sensor 30 is also provided downstream of the accumulator 18.
[0044]
In the embodiment of FIG. 4, the pipe 14 is formed of a highly rigid material pipe, as in the first embodiment of FIGS. 1 and 2. This is because, when the pipe 14 is made of a flexible material, the pulsation generated in the accumulator 18 and propagating into the chemical liquid is attenuated due to expansion and restoration of itself.
[0045]
In FIG. 4, the return pipes 14-1 and 14-2, the relief valve 32, the variable orifice 34, the bell mouth 36, and the check valve 38 are the same as those in FIGS. 1 and 3.
[0046]
The chemical solution for ground improvement stored in the tank 12 is added with a head by a pump 16 and flows through the pipe 14, and through a flow path (not shown) in the rod 40 inserted into the boring hole H, It penetrates into the ground from a monitor 42 (not shown) at the tip of the rod 40.
In FIG. 1, a state in which the chemical liquid is injected from the monitor 42 is indicated by an arrow A.
[0047]
“Pulsation in the chemical flowing through the pipe 14” is not much different from the injection method that does not give pulsation at a frequency of less than 100 Hz, as explained in FIG. Therefore, for example, it is set to 100 Hz.
A combination of the accumulator 18 and the pressure sensor 30 causes a pulsation with a desired frequency.
[0048]
The monitor 42 is provided with a pressure sensor 44, and the pressure sensor 44 measures the amplitude (pressure amplitude) of the injection pressure when the chemical solution is injected (arrow A).
The pressure amplitude in the chemical solution injection measured by the pressure sensor 44 is supplied to the control means 20 by the signal transmission line CL-1, and the amplitude of the pulsation in the chemical solution flowing through the pipe 14 generated by the accumulator 18 is controlled by the pressure amplitude. Is done.
[0049]
By performing the same control as described above with reference to FIG. 2, the amplitude of the pulsation generated in the accumulator 18 is controlled, and the pressure amplitude of the injection pressure is obtained (by various investigations performed prior to the injection method). This is in order to improve the chemical injection efficiency by adjusting the pressure amplitude within the optimum range for the chemical injection in the ground to be improved.
[0050]
The chemical injection monitor 42 is further provided with an ultrasonic wave generating means 50. The ultrasonic waves generated by the means 50 add ultrasonic vibrations, for example, 10 to 40 kHz, more preferably 20 kHz, to the chemical solution injected from the nozzle (not shown) of the monitor 42.
As described in relation to FIG. 3, as the ultrasonic wave generation means 50, a known and commercially available one (for example, a piezoelectric element type) may be applied, and if it can withstand the environment of the construction site of the injection method, There is no particular limitation. Then, an alternating current is supplied to the piezoelectric element of the ultrasonic wave generation unit 50 through the cable C1.
[0051]
As a result of ultrasonic vibration being added to the injected chemical, the particles of soil G move, the apparent viscosity coefficient decreases, and it becomes easier for chemicals for ground improvement such as grout to enter the soil G. Is done efficiently. In particular, when the ground G is a rock or the like, it becomes easy to inject a chemical into a crack or a crack in the rock, and the injection efficiency is improved.
[0052]
As described in connection with the embodiment of FIG. 3, the ultrasonic wave is very easily attenuated. However, in the embodiment of FIG. The distance from the generation source to the location where the ultrasonic wave is to be added is very short, and the ultrasonic wave is added with almost no attenuation.
[0053]
Other configurations and operational effects in the embodiment of FIG. 4 are the same as those of the first embodiment (FIGS. 1 and 2) and the second embodiment (FIG. 3).
[0054]
The illustrated embodiment is merely an example, and it is added that the present invention can be modified and modified in various ways other than illustrated.
[0055]
【The invention's effect】
The effects of the present invention are listed below.
(1) The accumulator generates a pulsation having a frequency that is sufficiently high to exert the effect of adding pulsation and low enough to prevent the pulsation from being attenuated, for example, a pulsation of 100 Hz, for example, in the drug solution to be injected. I can do it.
(2) Ultrasonic vibration can be applied to move the soil particles to reduce the apparent viscosity coefficient, thereby making it easier for the chemical solution to enter the soil.
(3) It is possible to prevent the pulsation from being absorbed when the pipe through which the injected chemical solution flows is made of a highly rigid material and the pipe itself expands and restores.
(4) By measuring the pressure amplitude of the injection pressure and controlling the pressure amplitude in the accumulator, the chemical solution can be injected into the ground with the optimal injection pressure amplitude in the soil to be injected.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first embodiment of the present invention.
FIG. 2 is a flowchart illustrating a control performed in the first embodiment.
FIG. 3 is a block diagram showing a second embodiment of the present invention.
FIG. 4 is a block diagram showing a third embodiment of the present invention.
[Explanation of symbols]
G: Ground to be improved H ... Boring hole 12 ... Chemical storage tank 14 ... Piping 16 ... Pump 18 ... Accumulator 20 ... Control means 22 ... Pump Drive motors 24, 28, 30, 44 ... pressure sensor 26 ... pressure sources 14-1, 14-2 ... return pipe 32 ... relief valve 34 ... variable orifice 36 ... bell Mouse 38... Check valve 40... Rod 42... Chemical injection monitor 50.

Claims (2)

  A rod (40) having a chemical solution injection monitor (42) at the tip is inserted into a bore hole (H) drilled in the ground (G) to be improved, and a chemical solution for ground improvement is injected from the chemical injection monitor (42). In the injection apparatus, a ground improvement chemical storage tank (12) on the ground side, a pump (16) for supplying the ground improvement chemical stored in the storage tank (12), the pump (16) and the rod A pipe (14) connecting the pipe (40), and a pressure source (26) for causing pulsation in the ground improvement chemical solution flowing through the pipe (14), and downstream of the pump (16) in the pipe (14) And an accumulator (18) connected to the region on the side, and a pressure sensor (44) provided in the chemical injection monitor (42) measures the pressure amplitude to control the pressure source (26) of the accumulator (18). Is provided, and control means (20) for controlling the pressure amplitude of the pulsation generated in the accumulator (18) is provided. (44) is measured, and compared with the range of the injection pressure amplitude value stored in the storage block (46). If it is larger than the predetermined pressure amplitude, the amplitude on the accumulator (18) side is decreased. Has a function of maintaining the amplitude thereof, and, when small, increasing the amplitude of the accumulator (18) side.   The injection device according to claim 1, wherein the chemical solution injection monitor (42) is provided with an ultrasonic wave generating means (50).

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