JP2686514B2 - Non-excavation propulsion method of sludge injection type - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propulsion method for constructing a tunnel underground without injecting mud while pouring mud.

[0002]

2. Description of the Related Art FIG. 6 shows a conventional mud material injection type propulsion method. In the figure, 1 is a ground, 2 is a tip excavating device, 3 is a cutter, 4 is a mud material injection port, 5 Is the earth removal mechanism,
6 is an earth discharge pipe, 7 is a propulsion pipe, 8 is a starting shaft, and 9 is a propulsion jack. As shown in the figure, the mud material injection type non-excavation propulsion method performs stable excavation on various types of soil, so the mud material is injected into the earth and sand excavated by the cutter 3 and stirred,
While maintaining the stability of the cutting face, the fluidity of the excavated earth and sand is increased to a size at which the excavated earth and sand are excavated, and the earth excavating mechanism 5 continuously excavates the excavated earth and sand amount corresponding to the excavation amount. For this reason, in the mud material injection type propulsion method, the viscous mud material, which is mainly composed of bentonite and powdered clay, is poured and stirred into the excavated earth and sand accompanying the excavation, and the particle size of the excavated earth and sand We are excavating while improving the distribution, increasing the fluidity, and maintaining the stability of the face.

[0003]

Therefore, in sandy soil or gravel soil having a small internal friction angle, poor fluidity, and high hydraulic conductivity, bentonite / powdered clay is used in water.
It was necessary to improve the particle size distribution of excavated soil by improving the fluidity and maintain the stability of the cutting face by injecting a large amount of mud added with 0 to 40%. On the other hand, when pouring and agitating the above-mentioned bentonite / powdered clay in a large amount of 30 to 40% into the excavated earth and sand containing clay, the viscosity and adhesive force of the excavated earth and sand will become too large and flow in reverse. Since the property deteriorates and problems such as sticking of excavated soil to the cutter occur, it was necessary to inject bentonite and a mud material with a reduced amount of powdered clay into the excavated soil containing clay. This mud making process takes a lot of work, and automation has been conventionally required to reduce the construction cost and improve the working environment, but it is necessary to add a large amount of bentonite and powdered clay to make the mud Even with the same mix of bentonite and powdered clay, the developed viscosity is not constant due to the passage of time, water temperature, and brand, making it difficult to control the quality of the mud and excavating the earth and sand excavated at the tip. Soil quality is estimated from the situation to adjust the mud material, but high technical skill is required to determine the mix of the mud material. It is difficult to unmanned, and human labor is unavoidable. Furthermore, in order to adjust the mud material by observing the earth removal condition of the earth and sand excavated at the tip,
It is difficult to dig because it is difficult to dig because the adjustment of the mud material goes around and the misalignment of the mud material often causes troubles such as scattering of the mud material to the ground and clogging of the excavated soil to the cutter. It was a bottleneck to speeding up the injection-type propulsion method. In addition, since a large amount of bentonite is injected into the excavated sediment, it is difficult to dispose of the discharged sediment. The present invention has been proposed to remedy the above drawbacks,
Its purpose is to add bentonite and powdered clay
It can be created with a small amount of addition, and the expressed viscosity is constant with the passage of time, water temperature, and brand, quality control is easy, and it is possible to create a mud material by changing to a mud material that does not require adjustment of the mud material depending on the soil quality. The purpose is to achieve economical compact automation of equipment and automation of earth removal management, to reduce construction costs and improve the working environment. In addition, by adopting a construction method that has a wide range of application to the soil and can apply the same mud material from sandy soil or gravel soil to cohesive soil, it is possible to eliminate the possibility of excavation due to improper adjustment of the mud material and inject the mud material. It is to provide speeding up of the mold propulsion method. In addition, by using a method of pouring a mud material that does not use bentonite, discharged earth and sand that does not contain bentonite can be obtained, and the discharged earth and sand can be easily discarded.

[0004]

[Means for Solving the Problems] In order to achieve the above object, in a non-excavation propulsion method of a sludge-added material injection type, bentonite, powder obtained by dissolving a polymer showing a high viscosity with a small amount of the sludge-added material in water. The gist of the invention is a mud material injection type non-excavation propulsion method characterized by being a mud material with a low concentration and a high viscosity that does not contain clay or the like. The present invention, bentonite prepared by dissolving a small amount of a polymer exhibiting a high viscosity in a small amount, such as a special carboxymethyl cellulose having a high degree of etherification, in water in the earth and sand excavated by a mud material injection type propulsion method. Low concentration that does not contain powdered clay, etc.
By injecting a highly viscous polymer solution as a mud material, sandy soil or gravel soil can be excavated while maintaining the stability of the cutting face by retaining and fluidizing the gravel content in the sand due to the high viscosity of the mud material. (Conventionally, improvement of particle size distribution of excavated soil,
The fluidization of excavated soil and the stability of the cutting face were maintained by the specific gravity of the mud material) and the cohesive soil was obtained by coating the excavated soil with a high-viscosity polymer solution to deprive the clay of the excavated soil of the adhesive force to the cutter. Preventing the excavated sediment from sticking and fluidizing the excavated soil moderately due to the viscosity of the mud material (In the past, the moisture content of the cohesive soil was increased by the water content of the mud material to fluidize it. ), It is possible to apply a small amount of polymer at a certain concentration to water, based on the idea that the same mixing agent can be applied from sandy soil or gravel soil to cohesive soil.
This is a mud material injection-type propulsion method that enables the use of an inexpensive compact automatic mud material preparation device that stirs. Table 1 shows a comparison with conventional automatic mud making equipment using bentonite and powdered clay. In addition, based on the above idea, since mud materials of the same composition can be applied from sandy soil or gravel soil to cohesive soil, it is possible to eliminate the possibility of excavation due to improper adjustment of mud material, Enables speeding up. In addition to this, by using the polymer solution as a sludge additive, a method of injecting a sludge additive that does not use bentonite was adopted, and by using discharged soil that does not contain bentonite, it was possible to easily discard the discharged soil.

[0005]

The present invention is a low concentration / high clay content containing no bentonite / powdered clay, etc., created by dissolving a polymer that exhibits high clay in a small amount in water, to the earth and sand excavated by the mud material injection type propulsion method. By increasing the fluidity of the excavated soil by injecting and stirring the polymer solution as a mud material, and making the excavation while maintaining the stability of the cutting face, it became possible to use an inexpensive small automatic mud material preparation device. .

[0006]

Next, an embodiment of the present invention will be described. It should be noted that the embodiments are merely examples, and it is needless to say that various changes or improvements can be made without departing from the spirit of the present invention. Used in the method of the present invention, a low concentration and high viscosity mud material prepared by dissolving a small amount of a polymer exhibiting a high viscosity in a small amount such as special carboxymethyl cellulose having a high degree of etherification in water, and a conventional method Create a mud material made of bentonite and powder clay for use in
This was poured into various excavated sediments and stirred, and the effect of improving the fluidity of excavated sediments was measured.

In FIG. 1, the polymer solution was injected as a mud material.
The fluidity of the agitated excavated sediment and the fluidity of the excavated excavated soil with bentonite and powdered clay injected and agitated are shown.
In the figure, the horizontal axis is the viscosity, and the vertical axis is the flotation limit of gravel in the sludge and the fluidity of the mixed soil. As shown in the figure, the sludge added with the polymer solution has a viscosity of 18000 mPa · S and can float 40 mm of gravel on gravel ground and 4.5 cm of fluidity on cohesive soil. It can be seen that the same mixture of mud can be applied from soil or gravel soil to cohesive soil. On the other hand, the bentonite / powdered clay mud material requires a viscosity of 8500 mPa · S to float 40 mm gravel.
Viscosity of 2200 mPa.S to give fluidity of cm
Need mud material. In other words, the gravel ground is 8500m
Pa / S mud is required, and 220 is used for cohesive ground.
It can be seen that the application range of the mud material is narrow because the mud material of 0 mPa · S is required and the mud material needs to be changed depending on the soil quality.

FIG. 2 (a) shows the polymer solution concentration, and FIG. 2 (b) shows the weight concentration of the bentonite / powdered clay added to the water. The horizontal axis shows the concentration of the sludge additive, and the vertical axis shows the viscosity. As shown in the figure, in the polymer solution,
It is recognized that a small amount of ~ 2% material can be used to make a mud material. On the other hand, it can be seen that a large amount of bentonite / powdered clay mud material, 30 to 40% of the weight of water, is required to prepare the mud material.

FIG. 3 shows the amount of increase in viscosity of the sludge containing the polymer solution and bentonite / powdered clay over time. The horizontal axis represents elapsed time and the vertical axis represents viscosity. As shown in the figure, in the polymer solution, the amount of viscosity increase of the mud additive with time can be made smaller than that of bentonite / powder clay.

FIG. 4 shows the amount of change in the expressed viscosity with temperature of the sludge made of the polymer solution and bentonite / powdered clay. The abscissa represents the temperature of preparation of the mud and the ordinate represents the viscosity.
As shown in the figure, the polymer solution can eliminate the influence of the temperature on the viscosity of the mud additive. On the other hand, it can be seen that temperature of bentonite / powdered clay has a large effect on the viscosity of mud added.

FIG. 5 shows the injection resistance of the sludge added with the polymer solution and bentonite / powdered clay. Injection distance on the horizontal axis,
The vertical axis is the injection pressure. As shown in the figure, the injection resistance can be reduced in the polymer solution.

Next, using a sludge made of a polymer solution,
A specific method of performing the construction method will be described. First, by taking advantage of the characteristics of the sludge additive made of polymer solution, the viscosity can be reduced to 1 by using the compact automatic sludge additive preparation device that is manufactured at low cost by combining a small stock tank, a powder quantitative supply device, and a small mixer.
8000mPa · S polymer mud material is continuously prepared. Next, since the injection resistance of the polymer mud material is small, the miniaturized injection pump injects the polymer mud material into the ground,
Stir with a cutter. The polymer mud material maintains the stability of the cutting face by keeping the gravel content in the sand and fluidizing it due to the high viscosity of the polymer solution in sandy soil or gravel soil, and in the case of cohesive soil, the excavated soil is coated with a high viscosity polymer solution. By removing the adhesive force of clay in the sediment to prevent clinging of the excavated sediment to the cutter, and by appropriately fluidizing the excavated soil with the viscosity of the polymer solution, the viscosity of the polymer mud material can be adjusted. Instead, it is suitable for all types of soil from sandy soil or gravel soil to cohesive soil, fluidizes the soil moderately and discharges the excavated soil corresponding to the amount of excavation to the ground by the soil discharge mechanism to perform stable excavation. In addition, since the fluidity of excavated soil is large, the soil discharge mechanism is downsized.

[0013]

As described above, according to the present invention, a bentonite / powdered clay laminating material is used to dissolve a polymer exhibiting a high viscosity in a small amount with water to obtain a low concentration of bentonite / powdered clay. By changing to a high viscosity polymer solution mud material, an inexpensive small automatic mud material preparation device can be used, a small injection device, and a small earth removal mechanism It has a particularly excellent effect of improving the environment, reducing the construction cost, and downsizing the vertical shaft site. Furthermore, if a polymer solution is used, it is possible to prepare a mud material with a small amount of material. Also, without adjusting the viscosity of the polymer mud material,
By adapting to all types of soil, from sandy soil or gravel soil to cohesive soil, troubles and adjustments due to poorly adjusted mud materials can be eliminated, and economic construction can be achieved. Other,
The method of the present invention is such that, when pouring and agitating the mud material into the sand and fluidizing it, the fluidity given to the sand is larger than that of the conventional method, that is, there is little change in viscosity over time and bentonite. Since it does not include the above, the method of transporting earth and sand by pipes has the effects of reducing pressure loss and facilitating disposal of earth and sand.

[Brief description of the drawings]

[Fig. 1] Relationship between the diameter of gravel that can be floated when gravel is thrown into mud material and the viscosity of the mud material, and the flow rate of soil and sand mixed with the mud material and the viscosity of the mud material Show the relationship.

FIG. 2 shows the relationship between the weight concentration of a sludge addition material with respect to water and the viscosity of a sludge addition material. (A) is a case of a polymer addition material, and (b) is a case of bentonite / powdered clay addition material.

FIG. 3 shows the relationship between the elapsed time after preparation of the sludge and the viscosity of the sludge.

FIG. 4 shows the relationship between the mud material preparation temperature and the mud material viscosity.

FIG. 5 shows the injection resistance of the mud material.

FIG. 6 shows an example of a mud material injection type propulsion method.

[Explanation of symbols]

 1 Ground 2 Tip excavation device 3 Cutter 4 Additive mud material injection port 5 Soil removal mechanism 6 Soil discharge pipe 7 Propulsion pipe 8 Start vertical shaft 9 Propulsion jack

Claims (2)

(57) [Claims] 1. A mud material-injection type non-excavation propulsion method, in which a mud material is a low concentration and high viscosity solution containing no polymer such as bentonite, powdered clay, etc. The mud material injection type non-excavation propulsion method characterized in that the mud material is continuously excavated from the tip of the tip excavation device while continuously pouring the mud material into the ground. 2. The mud material has a viscosity of about 18000 m.
It is Pa * S, The mud material injection type non-excavation propulsion method of Claim 1 characterized by the above-mentioned.