JP3731870B2 - Flow material injection method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention applies liquid or other fluid materials for the purpose of chemical injection for the purpose of ground improvement, grouting work for cracked rocks containing fine cracks in the rocks, or repairing and filling cracks or narrow parts of concrete structures. The present invention relates to a method and an apparatus for injecting a fluid material used for repair work to be infiltrated.
[0002]
[Prior art]
In the conventional general static injection method, an appropriate injection rate is set according to the geological conditions, the pump is kept at a constant pressure so as not to pulsate as much as possible, and the injection is performed at a constant rate. The injection was continued until the injection amount or the injection limit was reached.
In such an injection method, a large amount is injected only into a portion that is easy to be injected. For example, in rock mass injection, it is difficult to inject into a fine crack portion, and only a large crack is injected far away. And a filling part tends to become non-uniform | heterogenous. Moreover, in the soil ground, split injection tends to occur and the permeability may be small.
[0003]
Therefore, various dynamic injection methods have been proposed recently (see, for example, Japanese Patent Application Laid-Open No. 2000-27171). In these methods, an injection material is pumped and a constant period of pressure is superimposed on its basic pressure, and the injection efficiency is improved by a change in the pressure of the injection material.
[0004]
However, when pressure fluctuations of a certain period are simply added to the basic pressure in this way, clogging occurs between the soil particles or microcracks in the rock (the gel is injected when chemicals are injected, and the particles are added when cement milk is used). There was a problem that the injection amount decreased with time.
[0005]
[Problems to be solved by the invention]
Therefore, the present invention is intended to improve the ground by injecting chemicals, grouting cracked rocks containing microcracks in the rock, or repairing liquids and other fluids for the purpose of repairing and filling cracks or narrow parts of concrete structures. An object of the present invention is to provide a fluid material injection method and apparatus capable of solving the problem that clogging occurs and the amount of injection decreases with time in a fluid material injection method used in repair work for infiltrating the material. It is said.
[0006]
[Means for Solving the Problems]
According to the injection method of the fluid material of the present invention, the fluid material such as the injection material is pumped by the pumping means (1) and injected from the injection means (2) provided for the injection target such as the ground or the structure. In the flowable material injection method, a pressure control means (C) is connected to a pressure feed line (3) that communicates the pressure feed means (1) and the injection means (2), and the pressure control means is connected to the flowable material. A predetermined set injection pressure (P0) and a pressure (P1) lower than the predetermined set injection pressure are generated in the pumping line (3), and the injection pressure of the fluid material is injected into the injection target for an arbitrary duration (t). Injection is performed at a pressure (Pn) lower than the resistance pressure (P10) acting on the injection material such as ground pressure and water pressure around the means.
[0007]
Further, according to the method of injecting a fluid material of the present invention, the injection pressure of the fluid material is changed to a resistance pressure (P10) acting on an injection material such as a ground pressure or a water pressure around an injection means in an injection object in an arbitrary repetition cycle. The injection is performed at a lower pressure (Pn).
[0009]
A surge pressure absorbing means (10) is connected to the pressure control means (C) to absorb the surge pressure.
[0010]
According to the fluid material injection device of the present invention, fluid material such as an injection material is pumped by the pumping means (1) and injected from the injection means (2) provided for the injection target such as the ground or a structure. In the flowable material injection apparatus, a pressure control means (C) is connected to a pressure feed line (3) communicating the pressure feed means (1) and the injection means (2), and the pressure control means comprises a flowable material. A predetermined set injection pressure (P0) and a pressure (P1) lower than the predetermined set injection pressure are generated in the pumping line (3), and the injection pressure of the fluid material is injected into the injection target for an arbitrary duration (t). It has a function to control injection so that the pressure (Pn) is lower than the resistance pressure (P10) acting on the injection material such as the earth pressure and water pressure around the means.
[0011]
The pressure control means includes a negative pressure generating means, and the negative pressure generating means and the negative pressure so as to transmit the negative pressure generated by the negative pressure generating means to the pressure feed line via the negative pressure transmitting means. The transmission means is preferably configured to communicate with a pressure transmission line in which a pressure transmission fluid is sealed.
[0012]
Further, according to the fluid material injection device of the present invention, the injection pressure of the fluid material is set to a resistance pressure (P10) that acts on the injection material such as the earth pressure and water pressure around the injection means in the injection target in an arbitrary repetition cycle. The injection is controlled to be performed at a lower pressure (Pn).
[0013]
For the pressure control of the repetitive cycle, it is preferable to control the pressure control means by providing a pulsation generating means such as a plunger pump to generate the pulsation.
[0015]
A surge pressure absorbing means (10) is connected to the pressure control means (C).
[0016]
Conventionally, in filters using gravel and sand for water purification, so-called backwashing has been carried out in order to eliminate clogging by passing water from the reverse direction through the filtration capacity that decreases with the passage of time of use. Is known.
According to the present invention, a momentary negative pressure or a cyclic positive / negative repetitive pressure of a predetermined time from an extremely short time to a continuous time adapted to the injection target is transmitted to the pressure feed line by the pressure control means, and the pressure feed means sends the injection means. It is added to the basic pressure of the flowable material that is pumped toward. Therefore, a lower pressure than the ground pressure, water pressure, etc. is generated with respect to the injection pressure of the fluid material from the injection means, and clogging is prevented in the same manner as the backwashing, and the injection amount decreases with time. Injection is done without.
[0017]
In addition, when a low pressure instantaneously occurs with respect to the ground pressure, water pressure, etc., an excessive surge pressure may be generated, which may destroy or significantly disturb the composition of the injection target or the region. On the other hand, it is desirable to connect a surge pressure absorbing means to the pressure transmission line, and this apparatus suppresses the surge pressure.
[0018]
The surge pressure absorbing means is preferably an accumulator or a surge tank combined with a flow rate adjusting valve.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In FIG. 1, an injection material pipe 3 communicates as a pumping pipe line from an injection fluid pump 1 which is a pumping means to an injection means 2 (for example, a nozzle, not shown) provided for an injection target of the ground or a structure. Has been. And the pressure control means C is connected to the injection material pipe line 3.
The pressure control means C is connected to the negative pressure generating means 5, the negative pressure transmitting means 6, and the negative pressure generating means 5 to one end of the negative pressure transmitting means 6 and is connected to the injection material pipe 3 from the other end. It is comprised with the pressure transmission line 9 currently made.
[0020]
The pressure transmission line 9 is filled with a pressure transmission fluid that is an incompressible fluid and does not cause a phase change (for example, boiling) during operation. Further, the inside of the negative pressure transmitting means 6 is isolated by a diaphragm, for example, and the negative pressure generated by the negative pressure generating means 5 is transmitted by an incompressible fluid, and the volume change is injected by the flexibility of the diaphragm. It is configured to be transmitted to the injection material in the material pipe line 3.
The diaphragm in the negative pressure transmission means 6 isolates the pressure transmission fluid from the injection material and transmits the pressure generated by the negative pressure generation means 5 to the injection material, such as a slidable plunger. But it doesn't limit the format.
[0021]
Further, an accumulator 7 is communicated with the pressure transmission line 9 via a flow rate adjusting valve 8 to constitute a surge pressure absorbing means 10.
The surge pressure absorbing means 10 is not limited to an accumulator, and may be anything that can absorb surge pressure, and may be a surge tank, a hydraulic cylinder, or the like, and is not limited to these examples. The flow rate adjusting valve 8 is a means for facilitating the adjustment of the degree of absorbing the surge pressure, and is not necessarily required to be mounted. In order to adjust the degree of absorption of surge pressure, means 11 for supplying a compressive fluid under pressure to the accumulator 7 or a surge tank may be connected.
[0022]
The negative pressure generating means 5 is a pulsating negative pressure generating means that is composed of a plunger pump that converts a rotational force of a motor (not shown) into a reciprocating motion by a crankshaft, and repeatedly generates periodic pulsations. In general applications, the plunger pump is multi-connected for the purpose of suppressing pulsation. However, in the present invention, a single-acting type is preferable for giving pulsation, and it is not possible to use some of the multiple plungers. You may create continuity. Further, it is more effective because a large pulsation waveform can be obtained by selecting a plunger pump having a larger stroke than the bore of the plunger pump.
The motor that operates the negative pressure generating means (plunger pump) 5 is generally an AC inverter system, and a hydraulic motor or the like may be used. Then, the cycle and operating time of the generated negative pressure are controlled by controlling the rotational speed.
[0023]
In this way, the initial pressure of the injection material in the injection material pipe 3 is transmitted to the negative pressure transmission means 6 through the pressure transmission fluid by appropriately combining the volume change amount and the change rate of the negative pressure generation means 5. In contrast to (indicated by reference numeral A), periodic high and low pressures are generated as indicated by reference numeral B between the pressure control means C (negative pressure transmission means 6) and the injection means 2 thereafter.
[0024]
The negative pressure generating means 5 may be of any structure that can cause a volume change other than the above plunger system, and the structure is not particularly defined.
Further, the negative pressure generating means 5 and the negative pressure transmitting means 6 may be configured integrally or may be installed so as to be separable. Furthermore, a structure in which the plunger of the negative pressure generating means 5 directly transmits the negative pressure to the injection material in the injection material pipe 3 may be adopted.
[0025]
With the above configuration, the pressure control means C, as shown in FIG. 2, is a “predetermined set injection pressure of fluid material” P0, that is, a pressure at which an injection material or the like can permeate an injection target such as the ground or a structure, And “pressure lower than the predetermined set injection pressure” P <b> 1 is generated in the injection material pipe 3.
And, as “pressure lower than the predetermined injection pressure” P1, the pressure lower than the resistance pressure P10 acting on the injection material of the injection means 2 around the injection means 2 in the injection target is set to an arbitrary duration t. Repeat time T (variable from 0 to infinity).
In the above description, “negative pressure” refers to a low pressure with respect to the ground pressure / water pressure indicated by the symbol Pn in FIG.
[0026]
As the injection pressure P, a momentary or periodic high / low pressure is applied to the injection portion by appropriately selecting the volume change amount and the temporal volume change rate in the negative pressure generating means 5 (see p in FIG. 2). In addition, the injection can be promoted, so-called clogging can be prevented, and the injection flow rate that decreases with the passage of time can be improved.
[0027]
Further, an accumulator 7 is provided for the surge pressure generated due to the excessive volume change amount and change rate, and the generation of an excessive surge pressure is suppressed. A flow rate adjusting valve 8 is interposed between the negative pressure transmitting means 6 and the accumulator 7 to constitute a surge pressure absorbing means 10, and the pressure adjustment can be arbitrarily set.
[0028]
【The invention's effect】
This invention is comprised as mentioned above and produces the effect shown below.
(1) In the chemical injection work to improve the ground, a short or instantaneous pressure is applied to the chemical to be injected and a pressure lower than the ground pressure or water pressure acting on the injection part in the natural state is generated. Improves infusion flow that promotes infusion and decreases over time.
(2) In the grouting work for cracked rocks including microcracks in the rock, a lower pressure such as ground pressure or water pressure is generated in the grouting material to be injected as in the previous section, and the injection is promoted and decreases with time. Increase injection flow rate.
(3) In repair work where liquids or other fluid materials are infiltrated into cracks or narrow areas of concrete structures for the purpose of repair filling, etc., a lower pressure than ground pressure or water pressure is applied to the filler to be injected as in the previous section. To promote injection and improve the injection flow rate that decreases with time.
(4) The problem of destruction or significant disturbance of the composition of the injection target or the region due to generation of excessive surge pressure can be prevented by connecting surge pressure absorbing means to the pressure transmission line.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.
FIG. 2 is a view for explaining injection pressure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Injection fluid pump 2 ... Injection means 3 ... Injection material pipe line 5 ... Negative pressure generation means 6 ... Negative pressure transmission means 7 ... Accumulator 8 ... Flow control valve 9 ... Pressure transmission line 10 ... Surge pressure absorbing means C ... Pressure control means

Claims (6)

  In the method of injecting a fluid material, such as an injection material, which is pumped by a pumping means (1) and injected from an injection means (2) provided for an injection target such as a ground or a structure, the pumping means (1 ) And the injection means (2) are connected to the pressure feed line (3), the pressure control means (C) is connected, and the pressure control means uses the predetermined set injection pressure (P0) of the fluid material and the predetermined set injection pressure. Lower pressure (P1) is generated in the pumping line (3), and the injection pressure of the flowable material acts on the injection material such as the earth pressure and water pressure around the injection means in the injection target for an arbitrary duration (t). An injection method for a flowable material, wherein injection is performed at a pressure (Pn) lower than the resistance pressure (P10). The injection is performed by setting the injection pressure of the fluid material as a pressure (Pn) lower than a resistance pressure (P10 ) acting on the injection material such as a ground pressure and a water pressure around the injection means in the injection target in an arbitrary repetition cycle. A method for injecting the fluid material as described.   The method for injecting a fluid material according to claim 1 or 2, wherein a surge pressure absorbing means (10) is connected to the pressure control means (C) to absorb the surge pressure.   In the flowable material injection apparatus, a flowable material such as an injection material is pumped by a pumping means (1) and injected from an injection means (2) provided for an injection target such as a ground or a structure. ) And the injection means (2) are connected to the pressure feed line (3), and the pressure control means (C) is connected to the predetermined setting injection pressure (P0) of the fluid material and the predetermined setting injection. A pressure (P1) lower than the pressure is generated in the pumping line (3), and the injection pressure of the flowable material acts on the injection material such as the earth pressure and water pressure around the injection means in the injection target for an arbitrary duration (t). An apparatus for injecting a fluid material, which has a function of controlling to inject as a pressure (Pn) lower than a resistance pressure (P10).   The injection pressure of the fluid material is controlled to be injected at an arbitrary repetition cycle as a pressure (Pn) lower than a resistance pressure (P10) acting on the injection material such as a ground pressure and a water pressure around the injection means in the injection target. The fluid material injection device according to claim 4.   The fluid material injection device according to claim 4 or 5, wherein a surge pressure absorbing means (10) is connected to the pressure control means (C).

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