JP2552553B2 - Simultaneous injection method and equipment from multiple injection lines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention is an injection method for simultaneously injecting an injecting solution into a plurality of injecting holes in the ground through a plurality of injecting conduits branched from one injecting solution sending section. Related to the construction method and device, in particular, regardless of the difference in the injection resistance pressure of the ground in each injection hole or the change of the injection resistance pressure of the ground during injection, the injection liquid is sent to each injection pipe line at a predetermined injection speed. Therefore, the present invention relates to a ground injection method and apparatus capable of achieving desired injection from each injection hole and thereby solidifying the ground extremely quickly and reliably.

[Conventional technology]

Especially when a wide range of injection is required along the length of a road such as road construction in an urban area, or when injection is performed in a narrow work space such as a tunnel, injection from one injection liquid delivery part into multiple injection holes It was a big dream for engineers in this field to simultaneously send and inject liquids to rapidly solidify a wide range of ground in a short time with a minimum working space.

However, in general, the ground is generally formed by alternating layers of different grain size and water permeability, and not only the ground where each injection hole is located, but also one injection hole, the soil layer at each depth. Since the characteristics are different, insert multiple injection pipes in the ground,
Even if the injection liquid is passed from one pump to these multiple injection pipes at the same time to consolidate the ground, the injection liquid is concentrated and sent to specific injection holes located in a large permeable layer, and other injection liquids are injected. Almost no liquid is sent to the holes, and the whole cannot be uniformly consolidated.

Therefore, the conventional method is to inject into one infusion line through one infusion pump, complete all infusion stages, and then move to another infusion line. It has been taken.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to supply the injection liquid from one liquid supply unit to a plurality of injection holes and simultaneously inject the injection liquid, and at the same time for each injection hole or for each injection hole although the water permeability at each injection stage is different. It is an object of the present invention to provide a ground pouring method and apparatus capable of consolidating the ground extremely quickly and surely by injecting a predetermined amount into the ground.

[Means for solving problems]

In order to achieve the above-mentioned object, according to the method of the present invention, a plurality of injection pipes each branched from one liquid sending part for sending an injection liquid and provided with an injection nozzle inside are respectively provided. Installed separately for each injection hole in the ground, then
The injection liquid is simultaneously sent to the plurality of injection pipes through the liquid supply unit and simultaneously injected into the ground through the respective injection holes, and the internal pressure of the liquid supply unit is the injection nozzle of each of the injection pipes. Is maintained higher than the internal pressure at the downstream side of the injection hole, so that the injection pressure is injected into each of the injection pipes despite the difference in the injection resistance pressure of the ground in each injection hole or the change of the injection resistance pressure of the ground during the injection. The liquid is sent at a predetermined injection speed, and further, according to the device of the present invention, one liquid sending part for sending the injecting liquid, and a plurality of branches from the liquid sending part are provided in the ground. A plurality of injection pipes separately installed in each injection hole and an injection nozzle installed in each of the plurality of injection pipes are provided, and the internal pressure of the liquid feeding unit is set to the injection nozzle of each injection pipe. It is characterized by holding higher than the internal pressure of the downstream That.

 Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an explanatory view of a specific example of the device of the present invention.
Is a liquid feeding part for feeding an injection liquid for soil consolidation. As shown in the first drawing, the liquid feeding section 1 is composed of one conduit and has one end 1a.
Is connected to an injection liquid tank 2 that stores an injection liquid for soil consolidation, and the other end 1b is connected to a valve 3. Furthermore, the valve 3 is connected to the injection liquid tank 2 via the pipe line 4,
A circulation system passage 5 is formed by the valve 3, the pipe passage 4, and the injection liquid layer 4. A pump 6, a primary pressure gauge 7 and a primary flow meter 8 are provided in this order from the injection liquid tank 2 side between the injection liquid tank 2 of the liquid feeding section 1 and an injection pipe line 9 described later.

Further, as shown in the first drawing, a plurality of injection pipe lines 9, 9 ... 9 are provided between the primary flow meter 8 of the liquid sending part 1 and the valve 3 so as to branch from the liquid sending part 1. The injection nozzle 1 is provided at an arbitrary position inside each of the injection pipes 9, 9 ...
0, 10 ... 10 and each injection nozzle 10, 10 ...
・ Valves 11, 11 ・ ・ 11 are provided on the upstream side of 10, and a secondary flow meter 12 and a secondary pressure gauge 13 are provided on the downstream side.
The end portions 9a, 9a ··· 9a, which are sequentially provided from the injection nozzle 10 side and have a discharge portion 9b at the tip, are separately inserted into the injection holes 15, 15, · · 15 in the ground 14 and installed.

The injection nozzle 10 is formed, for example, by shielding the flow passage 9c of the injection pipe 9 with a funnel-shaped shielding plate 16 and tapering it in the flow passage direction as shown in FIG. , Any other can be used. FIG. 4 is a plan view of FIG. In addition, the discharge part 9b of the injection conduit 9 may be formed by an injection nozzle. In this case,
The injection liquid is injected while rotating the injection pipe line 9. Also,
It is also possible to provide a plurality of pipe lines in the injection pipe line 9 and inject the injection liquid from the injection port of the discharge part 9b while ejecting air from one pipe line.

Using the above-described device of the present invention, first, the valve 3 is closed and the valves 11, 11 ... 11 of the injection pipe lines 9, 9 ... 9 are opened, and the pump 6 is operated to inject the injection liquid in the injection liquid tank 2. Is simultaneously sent to a plurality of injection pipes 9, 9 ... 9 through one solution sending unit 1, and is simultaneously injected into the ground 14 through the respective injection holes 15, 15. At this time, the internal pressure of the liquid sending part (the injection nozzles 10, 10
.. (internal pressure on the upstream side of 10) is adjusted by adjusting the pressure of the pump 6, so that the injection nozzles 10 in the injection pipes 9, 9 ...
It is kept higher than the internal pressure on the downstream side of 10. This pressure difference is preferably 5 kg f / cm ² or more.

The present invention described above is applied to the ground 14 in each of the injection holes 15, 15 ...
Despite the difference in the injection resistance pressure of each of them or the change of the injection resistance pressure of the ground 14 during the injection, each injection pipe line 9, 9 ...
The injection liquid can be sent to the injection liquid 9 at a predetermined injection speed.

In the present invention, the internal pressure of the liquid feeding section 1 is kept constant, and the injection nozzles 10, 10 ...
・ It is also possible to set the diameter of 10 to be the same and to send the same amount of injection liquid (constant injection speed) to each of the injection pipes 9, 9 ... 9 respectively. Keeping it constant, and selecting the diameter of each injection nozzle 10, 10 ... 10 appropriately, the injection amount of the injection liquid into each injection pipe line 9, 9 ... 9 is respectively according to the injection resistance pressure of the ground. It can be adjusted to a desired amount, and the discharge speed of the injection liquid from the discharge portion 9b corresponds to the water permeability of the ground 14 by appropriately selecting the internal pressure of the liquid supply portion 1 and the diameter of each injection nozzle. It can also be set to the most suitable speed.

 Fig. 12 shows an example of the conversion system.

In FIG. 12, the nozzle diameters of the injection nozzles 10, 10, 10 are set to be different from, for example, n1, n2, and n3, and the valve 11,
The selective opening and closing of 11, 11 allows the conversion of the injection nozzles 10, 10, 10 during injection. This can also be done automatically by programming the computer beforehand.

The liquid feeding section 1 can be used together with the pump 6 as shown in FIG. 13 in addition to the first drawing. .. 9 are branched from the pump 6 in parallel via the conduit x.

FIG. 2 is an explanatory view showing a modified example of the present invention, and since it is configured by combining two sets of the same devices as in FIG. 1, detailed description thereof will be omitted. By using this apparatus shown in FIG. 2, the main agent liquid A and the reactive agent liquid B are sent to the plurality of injection conduits 9, 9 ... Pipeline 9
At the end 9a, the combined liquid is injected into the ground from the discharge part 9b.

Furthermore, the apparatus of FIG. 2 is also used when simultaneously injecting grout having a short gelation time from a plurality of injection tubes.

Further, as shown in FIG. 10, the present invention is also applied to an injection method in which a three-axis boring machine 17 is used to perform boring in three injection pipe lines 9, 9, 9 and then pull up while simultaneously injecting. , Furthermore, as shown in Fig. 11, the drainage pipe 18 is embedded in advance, and it is injected from a plurality of injection holes at one time to drive groundwater into the drainage hole so that pockets of groundwater do not occur in the consolidated ground. Then, it is also applied to an injection method in which a predetermined injection region 20 is injected all at once. 11th
In the figure, 19 is a Mansiette tube, and many inner tubes can be inserted into these many Mansiette tubes 19, 19, ... 19 to inject and consolidate the entire injection region 20 in an extremely short time. . It should be noted that, finally, the injection material is injected into the drain holes to solidify the peripheral portion. It is also possible to drain the pump from the drainage pipe during injection to create a condition in which the injectate can easily penetrate.

[Action]

The present invention focuses on in-pipe injection, in which the injection port diameter, that is, the diameter of the injection nozzle is made small, and the pressure on the upstream side of the nozzle is kept sufficiently high by the pump pressure to reduce the pressure on the downstream side of the nozzle. It utilizes the characteristic that a constant flow rate flows regardless of.

The graphs in Fig. 6 and Fig. 7 show the secondary pressure (kg) when the primary pressure is kept constant and the diameter of the injection port is changed.
5 is a graph showing the relationship between f / cm ² ) and flow rate. This experiment was conducted using the experimental apparatus shown in FIG. In FIG. 5, the injection liquid in the injection liquid tank a is sent to the upstream pipe line c by the operation of the pump b, and when the liquid is sent to the downstream pipe line d via the injection nozzle n, operation of the needle valve e. The pressure in the downstream pipe line d is changed by. The upstream pressure and flow rate are measured with a primary pressure gauge P1 and a primary flow meter F1.
The downstream pressure and flow rate are the secondary pressure gauge P2 and the secondary flow meter.
Each measurement was carried out with F2, and the results are shown in FIGS. 6 and 7.

FIG. 6 shows that, in FIG. 5, the diameter of the injection nozzle n is changed to three types of 1.5, 1.0 and 0.5 mm respectively, the hydraulic pressure on the primary pressure side is kept at 80 kg f / cm ² by the pump b, and the secondary pressure is maintained. It is the graph which measured the flow rate corresponding to the secondary pressure by changing the liquid pressure on the side by the needle valve e to 0-80 kgf / cm < ² >. FIG. 7 is a graph measured under the same conditions as in FIG. 6 except that the primary pressure was 50 kg f / cm ² . In this case, water was used as the liquid.

 The following can be seen from FIGS. 6 and 7.

(1) If the upstream pressure is kept sufficiently higher than the downstream pressure by the pump pressure through the injection nozzle having a diameter extremely smaller than the diameter of the injection pipe, it may be affected by a wide range of pressure changes on the downstream side. Instead, a constant flow rate can be maintained according to the nozzle diameter.

(2) It can be divided into a region (C) in which the flow rate corresponding to the secondary pressure maintains a substantially constant value and a region (D) in which the flow rate temporarily decreases.

(3) When the primary pressure is the same, the larger the injection nozzle diameter, the larger the flow rate, and the smaller the injection nozzle diameter, the smaller the flow rate.

(4) The flow rate increases as the primary pressure increases even with the same nozzle diameter.

(5) From the above, even if the resistance pressure of the ground changes during the injection or the resistance pressure of the ground is different, if the value is within a certain range, a predetermined flow rate corresponding to the primary pressure and the nozzle diameter is obtained. I know I will keep it.

(6) For example, if the secondary pressure rises and reaches the region (D) where the flow rate temporarily decreases while injecting with a nozzle diameter of Φ0.5 mm, the injection nozzle is Φ1.0 or Φ1.5 mm If converted to, the flow rate can be maintained at the predetermined flow rate again.

FIG. 8 shows another experimental apparatus. In FIG. 8, as in FIG. 5, the injection liquid in the injection liquid tank a is sent to the upstream pipe line c by the operation of the pump b, and the plurality of injection pipe lines g, g. f ... F and injection nozzles n, n ...
When the liquid is sent to the downstream side pipelines d, d ... D via n, the pressures in the downstream pipelines d, d ... D are changed by operating the needle valves e, e. The upstream pressure and flow rate are measured by the primary pressure gauge P1 and the primary flow meter F1, and the downstream pressure and flow rate are measured by the secondary pressure gauge P2 and
P2 ... P2 and secondary flow meters F2, F2 ... F2 were measured and the results are shown in the graph of FIG.

In FIG. 9, the curve (a) has a primary pressure of 50 kg f / cm ² , 10 injection nozzles with a diameter of 1.5 mm, the injection pipe line g,
g ·· g to branch valve f, f ·· f, injection valve n,
The flow rate is measured by sending the injection liquid to the downstream flow paths d, d ... D via n ... N and operating the needle valves e, e ... E to change the secondary pressure. is there. The curve (b) is a primary pressure of 80 kg f / cm ² , the flow rate was measured in the same manner as above using 5 injection nozzles with a diameter of φ1.5 mm, and the curve (c) was a primary pressure of 50 kg f / cm ^2. , Jet nozzle diameter φ
The flow rate was measured in the same manner as described above using 10 pieces of 1.0 mm, and the curve (d) shows the flow rate in the same manner as described above using a primary pressure of 80 kg f / cm ² and 10 injection nozzles with a diameter of φ0.5 mm. It was measured.

From FIG. 9, when the liquid is branched and sent from one liquid sending part to the many pipe lines through the injection nozzle, even if the injection resistance pressure of the ground during the injection fluctuates or the injection stage changes, Even if the resistance pressure of the ground changes, or even if the resistance pressure in each injection hole differs due to the difference in the ground where each injection pipe is located, if the pressure is within a certain range, the primary pressure, the injection nozzle It can be seen that a constant flow rate corresponding to the aperture can be obtained.

When the secondary pressure rises during injection and the prescribed flow rate cannot be maintained, the prescribed flow rate can be maintained by increasing the primary pressure or increasing the injection nozzle diameter. I also understand that.

〔Example〕

The present invention was carried out using the apparatus shown in FIG. First, the valve 3 is closed, and the injection pipe lines 9, 9 ...
After opening the valves 11, 11, ... 11 of 9, the injection liquid in the injection liquid tank ² was supplied to one liquid supply unit 1 while maintaining the pump pressure of the pump 6 at 80 kg f / cm ² . Here, the injection liquid is sent to the plurality of injection pipes 9, 9 ... 9 branched from the liquid supply unit 1 at a flow rate of 60 / min, and each injection nozzle 1 having a nozzle diameter of 1.5 mm.
12 from the discharge parts 9b, 9b ... 9b to the ground 14 through 0, 10 ... 10
Injected at a flow rate of / min. At this time, by maintaining the pressure on the upstream side of the injection nozzles 10, 10 ... 10 sufficiently high by the pump pressure of the pump 6, the pressure on the downstream side of the injection nozzles 10, 10 ... 10 changes with the injection time. Or, even if the injection pressure of each injection hole 15, 15 ・ ・ 15 is different due to the difference of the stratum, if the injection pressure is within 50 kg f / cm ² , it is always 12 / A constant flow rate of injection liquid of a minute was delivered. The upstream pressure and flow rate were measured by a primary pressure gauge 7 and a primary flow meter 8, respectively, and the downstream pressure was measured by a secondary pressure gauge 13 and a secondary flow meter 12, respectively. 1 valve after injection
1, 11 ... 11 are closed and the valve 3 is opened, so that the injection liquid passes through the pipe line 4 and the circulation system line 5 to make the injection liquid tank 2
I was returned.

According to the above, the primary pressure is kept constant and the diameter of the injection nozzle is fixed, so that despite the injection resistance pressure of the ground or the change of the resistance pressure, a constant injection is performed from a plurality of injection pipelines. It can be injected at a speed (injection amount per unit time).

Also, by maintaining the primary pressure constant and changing the diameter of the injection nozzle, the injection speed from each injection pipe in a plurality of injection pipes can be adjusted to a predetermined injection speed according to the difference in the water permeability of the injection ground. Can be injected.

For example, in FIG. 1 described above, the injection pipe lines 9, 9 ...
If one of the 9 has a low hydraulic conductivity and the other has a low hydraulic conductivity, the injection nozzle diameters are selected to be φ1.0 mm and φ0.5 mm, respectively. Optimal injection rates can be selected as / min and 3 / min.

Furthermore, by changing the primary pressure and converting the diameter of the injection nozzle, the most appropriate injection can be performed in response to changes in the water permeability of the injection stage in each injection hole in multiple injection pipes or changes in the water permeability of the injection ground during injection. Can be injected at a rate.

For example, when the injection stage of the injection pipe reaches a layer with a low hydraulic conductivity and it is desired to reduce the injection speed, the injection nozzle bore diameter is converted to a smaller one, or each nozzle diameter is converted and the primary pressure is adjusted. This allows the most appropriate injection.

In the above, the primary pressure is 10 kg f / cm ² or more, preferably 2 kg f / cm ² or more.

When the pressure is 10 kgf / cm ² or less, the secondary pressure increases, which makes it difficult to divert a predetermined flow rate to the plurality of injection holes. The differential pressure between the primary pressure and the secondary pressure is 2 kg f / cm ² or more, preferably 5
It is more than kg f / cm ² . This is because even if the flow rate is temporarily reduced, the pump pressure and the nozzle hole diameter can be converted to secure a nearly predetermined flow rate, but if the differential pressure becomes 2 kg f / cm ² or less, it becomes increasingly difficult to adjust them. . In addition, the area inside the injection conduit of the opening area of the nozzle opening (or,
Ratio to the inner area of the liquid transfer part) is 1/4 or less, preferably 1/1
It is 0 or less. This is because if it becomes 1/4 or less, the injection effect decreases, and it becomes difficult for the phenomenon of maintaining a constant flow rate to occur despite the increase in the downstream pressure.

〔The invention's effect〕

As described above, the present invention focuses on the in-pipe injection of the fluid, whereby the injecting liquid is diverted from one liquid sending section to a plurality of injecting pipe lines, and a predetermined flow rate is maintained even if the injecting resistance pressure is different. This ensures the simultaneous injection of multiple pores.

[Brief description of drawings]

FIG. 1 is an explanatory view of a specific example of the device of the present invention, FIG. 2 is an explanatory view of a modified example of the device of the present invention, FIG. 3 is a sectional view of a specific example of the injection nozzle according to the present invention, and FIG. Is a plan view of FIG.
FIGS. 5 and 8 are explanatory views of the apparatus used in the experiments, FIGS. 6, 7, and 9 are graphs showing the relationship between the secondary pressure and the flow rate, FIGS. 10 and 11, respectively. FIG. 12, FIG. 12 and FIG. 13 are explanatory views of modified examples of the device of the present invention. 1 ... Liquid sending part, 2 ... Injection liquid tank, 6 ... Pump, 9 ... Injection pipe, 10 ... Injection nozzle, 14 ... Ground, 15 ... Injection hole.

Claims (7)

(57) [Claims] 1. A plurality of injection pipes, each of which is branched from one liquid supply unit for supplying an injection liquid and has an injection nozzle inside, is separately installed in each injection hole in the ground. Then, the injection liquid is simultaneously sent to the plurality of injection pipes through the liquid supply unit and simultaneously injected into the ground through the injection hole, and the internal pressure of the liquid supply unit is set to the respective injection pipes. Is maintained higher than the internal pressure at the downstream side of the injection nozzle of the injection nozzle, so that despite the difference in the injection resistance pressure of the ground in the injection holes or the change of the injection resistance pressure of the ground during the injection, the injection pipes A method for simultaneously injecting injecting liquid from a plurality of injecting pipes, wherein the injecting liquid is sent to the passage at a predetermined injection speed. 2. The method according to claim 1, wherein the inner pressure of the liquid feeding section and the diameter of the injection nozzle of each injection pipe are set to be constant, whereby the same amount of injection is made in each injection pipe. A construction method in which the liquid is sent. 3. The method according to claim 1, wherein the inner diameter of the liquid feeding section is kept constant and each of the nozzle diameters is appropriately selected, whereby the injection amount into each of the injection pipes is determined. A construction method in which the desired amount is adjusted according to the injection resistance pressure of the ground. 4. The method according to claim 1, wherein the inner pressure of the liquid feeding section and the diameter of the injection nozzle are appropriately selected to inject the discharge speed of the injection liquid from the tip of the injection conduit. A construction method that is set to the most appropriate speed corresponding to the permeability of the ground to be ground. 5. The method according to claim 1, wherein the pressure difference between the upstream side and the downstream side of each of the injection nozzles is 5 kg f / cm ² or more. 6. A single liquid feeding part for feeding the injecting liquid, a plurality of injection conduits branching from the liquid feeding part and separately installed in respective injection holes in the ground, and Injection nozzles respectively installed in the injection pipes, and the internal pressure of the liquid feeding section is kept higher than the internal pressure downstream of the injection nozzles of the injection pipes. An injecting liquid, which is characterized in that the injecting liquid is sent to each of the injecting pipes at a predetermined injecting speed, regardless of the difference in the injecting resistive pressure of the ground in the hole or the change of the injecting resistive pressure of the ground during the injection. Simultaneous injection device from multiple injection lines. 7. The device according to claim 6, wherein the pressure difference between the upstream side and the downstream side of each of the injection nozzles is 5 kg f / cm ² or more.