JP3504435B2 - Transparent simulated soil as a substitute for soft soil and soil testing method using soft soil - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has developed a transparent simulated soil as a substitute for soft soil, and uses this developed transparent simulated soil as a substitute for soft soil when an external force is applied by a stirrer. Substitution of soft soil so that the internal state of soft soil can be estimated from outside at any time by three-dimensional visual observation and the internal state of soft soil can be estimated from the similarity rule between transparent simulated soil and soft soil. The present invention relates to a transparent simulated soil and a ground test method for soft soil using the same.

[0002]

2. Description of the Related Art Conventionally, as a means for visualizing the movement inside the soil when an external force is applied to a soft ground by an agitator, a method of two-dimensionally capturing the movement after applying the external force or in the middle as a cross section is known. Has been.

[0003] For example, a transparent plate such as transparent glass is vertically provided for partitioning, soft ground is deposited on one side partitioned by a vertical transparent body, and the inside of the soft ground can be seen through the transparent body from the other side. The movement inside the soil when an external force is applied to the soft ground by a stirrer is visualized from the outside through a transparent body.

[0004]

However, in the above-mentioned conventional means, the inside of the soft ground can be visualized only in the cross-sectional portion in contact with the transparent body, that is, in two dimensions.
Under the present circumstances, it is extremely difficult to visualize the movement inside the ground three-dimensionally, that is, in three dimensions.

The present invention has been made in view of the above problems and was devised to solve the problems. The purpose of the present invention is to use a transparent simulated soil developed as a substitute for soft soil. The external state of the transparent simulated soil as a substitute for the soft soil when an external force is applied by a stirrer is externally and three-dimensionally visually observed from the outside, and the soft soil is calculated from the similarity rule between the transparent simulated soil and the soft soil. It is an object of the present invention to provide a transparent simulated soil as a substitute for soft soil capable of estimating the characteristics inside the soil, and a ground test method for soft soil using the same.

[0006]

In order to achieve the above object, the transparent simulated soil as a substitute for the soft soil according to the invention of claim 1 is used in hot water of a predetermined water temperature at a weight ratio of 1: 1. It is composed of a transparent aqueous solution having a concentration of 2% to 5% obtained by mixing chitosan and a solvent in a ratio and stirring.

In a preferred embodiment, the solvent is lactic acid, and the water temperature of hot water is 40 ° C. The hot water may have a water temperature in the range of 30 ° C to 90 ° C, and the solvent may be an organic acid such as succinic acid, citric acid or acetic acid, or an inorganic acid such as phosphoric acid, hydrochloric acid, sulfuric acid or polymerized phosphoric acid. It may be

According to the sixth aspect of the present invention, the ground test method for the inside of soft soil using the transparent simulated soil as a substitute for the soft soil is an experiment in which the transparent simulated soil as a substitute for the soft soil has a transparent side surface. Put it in the tank, and from the top of the experimental tank downward, drive the model agitator similar to the actual agitator with the predetermined torque converted by the similarity rule while descending at the predetermined speed converted by the similarity rule and immerse it in the simulated soil. A means for discharging the colored simulated cement milk as a substitute for the cement milk from the tip side of the model agitator immersed in the simulated soil, and visually observing the movement inside the simulated soil from outside at any time. It consists of

[0009] Here, the colored simulated cement milk may or may not disappear in the simulated soil.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically based on the embodiments of the invention shown in the drawings.

[Embodiment 1] Here, FIG. 1 is a diagram showing a torque change of an actual soft soil measured by a vane tester, and FIG. 2 is a torque change of a chitosan aqueous solution measured by a vane tester. FIG.

Fill the container with hot water. The water temperature of hot water is 30
It has been confirmed by experiments that there is no problem in the range of 90 ° C to 90 ° C. From the viewpoint of promoting dissolution and removing bubbles, the water temperature of hot water is optimally about 40 ° C.

Chitosan is added while stirring hot water filled in a container. The amount of chitosan is calculated from a graph showing the relationship between concentration and adhesive strength. If the concentration is higher than necessary, the transparency will be lost and it will be difficult for bubbles to escape. The concentration is in the range of 2% to 5% as described later.

With further stirring, for example, lactic acid as a solvent is added. The amount of lactic acid is the ratio of 1 lactic acid to 1 chitosan by weight. In addition, as a solvent instead of lactic acid, phosphoric acid, hydrochloric acid, sulfuric acid, polymeric phosphoric acid can be used as an inorganic acid, and succinic acid, citric acid, acetic acid, etc. can be used as an organic acid. The amount of the solvent used instead of these lactic acids is 1 for each chitosan in a weight ratio.

The concentration of the aqueous solution in which chitosan and lactic acid are added to hot water is in the range of 2% to 5%. For example, an aqueous solution
If the concentration is 00 kg and the concentration is 2%, then 3 kg of chitosan and 3 kg of lactic acid are used for 294 kg of water (hot water). If the aqueous solution is 300 kg and its concentration is 3%, 291 kg of water (hot water) is chitosan 4.
5 kg and lactic acid 4.5 kg. When the aqueous solution is 300 kg and the concentration is 4%, it is 6 kg of chitosan and 6 kg of lactic acid for 288 kg of water (hot water). If the aqueous solution is 300 kg and its concentration is 5%, 285 kg of water (hot water) is 7.5 kg of chitosan and 7.5 kg of lactic acid.
It is kg.

Then, after adding lactic acid as a solvent, 1
Stir after 0 minutes. In this way, simulated soil as a substitute for soft soil is manufactured. The simulated soil consists of a transparent aqueous solution in which chitosan and a solvent such as lactic acid are mixed, and the concentration of the aqueous solution is in the range of 2% to 5%. When the concentration of the aqueous solution exceeds 5%, the transparency is lost, and when the concentration of the aqueous solution is less than 2%, the adhesive strength is insufficient and it cannot be used as a simulated soil.

Since air bubbles are mixed in the aqueous solution of the simulated soil immediately after the production, it takes time to wait for the air bubbles to escape.
That is, the simulated soil made of the mixed aqueous solution of chitosan and lactic acid produced in the above process is left as it is, for example, for about one day, and waits for bubbles to escape. After that, transfer to the experimental tank and wait again for bubbles to escape from the simulated soil consisting of the aqueous solution (about 1-2 days with the 3.5% aqueous solution).

When the concentration of the aqueous solution of chitosan produced as described above and a solvent such as lactic acid (hereinafter referred to as "chitosan aqueous solution") is within the range of 2% to 5%,
From the results of the vane shear test, it became clear that it has a shear property very close to that of disturbed soft clay, and it can be used as a substitute for soft soil.

The graph shown in FIG. 1 is the actual torque change of the soft soil measured by the vane tester. The graph shown in FIG. 2 is the result of the same test performed on the chitosan aqueous solution. Each torque change is shown for each concentration. As you can see from the graph, it is very similar to the actual characteristics of soft soil (absolute value is different). Therefore, it was found that the chitosan aqueous solution can be used as a substitute for soft soil by adjusting the similarity rule.

The transparent simulated soil as a substitute for the soft soil produced as described above was transferred to an experimental tank as shown in the drawing, and a model agitator supported so as to be vertically movable downward from the upper portion of the experimental tank, An external force is applied to the transparent simulated soil as a substitute for the soft soil in the experimental tank, the internal movement of the transparent simulated soil is visually observed from outside at any time three-dimensionally, and the inside of the actual soft soil is simulated using the law of similarity. To estimate the movement of.

[Embodiment 2] Next, an apparatus used for a ground test method inside soft soil using a transparent simulated soil as a substitute for the soft soil produced as described above will be described with reference to the drawings. The description will be made based on the following. Here, FIG. 3 is a schematic perspective view in which a part of the simulated ground test apparatus is omitted, FIG. 4 is a front view of the upper side of the simulated ground test apparatus, FIG. 5 (A) is a front view of the experimental tank, and FIG. Is a side view of the experimental tank, FIG. 6C is a plan view of the experimental tank, and FIG. 6 is a partially enlarged front view of the tip side of the model agitator.

In the figure, a simulated ground test apparatus 1 used for a ground test in soft soil using transparent simulated soil as a substitute for soft soil is an experiment in which a transparent simulated soil is used as a substitute for soft soil. It comprises a tank 2, a model agitator 3 supported on the upper part of the experimental tank 2 so as to be vertically movable, and a support mechanism 4 for supporting the model agitator 3 so as to be vertically movable.

The experimental tank 2 has an open top surface and closed four side surfaces and a bottom surface, and has a structure in which transparent simulated soil as a substitute for soft soil is put inside. The experimental tank 2 has a frame 2a forming its framework, and the four side surfaces of the frame 2a forming the framework are formed of transparent plates 2b such as transparent glass or transparent plastic. The transparent plate 2b can be visually observed.

A discharge port 2c is formed on the lower side surface of the experimental tank 2 so that the simulated soil inside can be discharged from the discharge port 2c after the test is completed. Further, diagonal members 2d for reinforcing the experimental tank 2 are attached to the lower portions of both side surfaces, respectively.

The model agitator 3 is a model device for agitating the simulated soil contained in the experimental tank 2. The model agitator 3 has a similar shape to that of an actual device, but its size is small and different. It is made small. That is, the shape is small, but the shape and the like are the same as those of the actual device. It is supported by a support mechanism 4 provided vertically on the upper part of the experimental tank 2 so as to be vertically movable. In this embodiment, the model stirrer 3 is provided with two rotary shafts 3a, 3a in parallel downwardly and slightly apart from each other.

A plurality of agitating blades 3b are provided so as to vertically project on the peripheral surface of each rotating shaft 3a facing downward, that is, on the lower end side. The stirring blades 3b at the same position project left and right, and the stirring blades 3b on the upper side or the lower side thereof are formed so as to be offset by 90 degrees, that is, projecting in the orthogonal direction.

Each rotary shaft 3a has a hollow cylindrical shape, and a tip wing 3c is formed at a downward tip, that is, a lower end of each rotary shaft 3a, and a cement to be described later is formed in a part of the tip wing 3c. A lower discharge hole 3d for discharging simulated cement milk as a substitute solution for milk is formed. Further, the upper discharge hole 3e is also provided on the side surface at the same position as the uppermost stirring blade 3b.
Are formed.

Further, the agitating blades 3b of the respective downward rotating shafts 3a are
A plurality of earth-discharging blades 3f are vertically formed on the upper side surface. Furthermore, two parallel rotating shafts 3a
The front end side, that is, the lower end side thereof is rotatably connected by the upper and lower horizontal connecting rods 3g, and the distance between the front end sides of the two rotary shafts 3a is kept constant.

The upper ends of the two rotary shafts 3a are linked to the distributor 3h. Above the distributor 3h is a speed reducer 3i.
The agitating motor 3j is provided via the agitating motor 3j, and the rotational driving force from the agitating motor 3j is distributed by the distributor 3g via the speed reducer 3i to rotationally drive the two rotary shafts 3a. There is. The distributor 3h, the speed reducer 3i, and the agitating motor 3j are an elevator board 4b of a support mechanism 4 described later.
Is attached to.

The support mechanism 4 supports the model agitator 3 provided downward so as to be able to move up and down, and the support frame 4a of the support mechanism 4 is vertically installed above the experimental tank 2. The support frame 4a has a vertically long rectangular skeleton, and an elevating plate 4b that moves up and down along the side surface is attached to the side surface of the front side of the support frame 4a.

The elevating plate 4b is composed of a horizontal plate having an upper part horizontally projecting forward and a vertical plate located below the horizontal plate. The stirring motor 3j is installed on the horizontal plate of the lift plate 4b, and the distributor 3g and the speed reducer 3i are attached to the side surface of the vertical plate below the horizontal plate. Further, a lateral horizontal plate horizontally projecting laterally is attached to one side of the vertical plate of the lift plate 4b, and a tank 6b described later is installed on the lateral horizontal plate.

Vertical grooves (not shown) are formed on the right and left sides of the back surface of the vertical plate of the lift board 4b, and the left and right vertical grooves are formed on the right and left sides of the front surface of the support frame 4a. A matching guide 4c is formed so as to project in the vertical direction, and the lift plate 4b is structured to move up and down while being guided by the guide 4c.

A screw rod 4d is attached to the center of the inside of the support frame 4a in the vertical direction so as to be rotatable around its axis. A spiral screw is cut on the side peripheral surface of the screw rod 4d. The screw rod 4d is screwed through a screw hole formed in a rear portion (not shown) of a vertical plate of the lift plate 4b, and the lift plate 4b is moved up and down by a screw motion by the rotation of the screw rod 4d.

The elevating motor 4e drives and rotates the screw rod 4d, and the screw rod 4d includes pulleys 4f and 4f.
And a timing belt 4g that is stretched between the pulleys 4f and 4f, and is linked to a lifting motor 4e. Pulleys 4f are attached to the upper end of the screw rod 4d and the rotating shaft of the lifting motor 4e, respectively. The elevating motor 4e is attached to the upper side surface of the support frame 4a.

Further, a counterweight 4h is provided which is in balance with the ascending / descending elevator 4b, and the elevator 4b and the counterweight 4h are connected by a rope 4i. That is, the rope 4i, one end of which is connected to the elevator board 4b, extends upward and is inverted by the roller 4j provided at the center of the upper end of the support frame 4a, and the counterweight 4h is connected to the other end that extends downward.

A torque detector 5 for detecting the rotational torque of each rotary shaft 3a is attached to the upper part of each of the two rotary shafts 3a. The torque detector 5 is connected to a computer (not shown) or the like, and the value measured by the torque detector 5 can be stored in the computer, displayed on the display, or printed by a printer.

On the outer peripheral side of the rotary shaft 3a slightly below the torque detector 5, there is a total of vertically connected rotary motion-compatible connectors 6 for supplying a cement milk substitute solution, which will be described later, into the hollow interior of each rotary shaft 3a. It is attached by four. That is,
Each rotating shaft 3a penetrates the connector 6 and is rotatably attached.

One end of each transport passage 6a for supplying a cement milk substitute solution described later is connected to each connector 6 mounted above and below each rotary shaft 3a. The other end of each transport passage 6a is connected to a tank 6b that stores simulated cement milk as a substitute solution for cement milk. The tank 6b is attached to the lift board 4b of the support mechanism 4 described above.

The air compressor 6c is a tank 6b.
It is a drive source for sending the solution inside to each hollow rotary shaft 3a through the transport passage 6a and the connector 6 using air pressure and discharging it into the simulated soil from the lower discharge hole 3d at the tip of each rotary shaft 3a. The air compressor 6c is installed at a location apart from the simulated ground test apparatus 1. An air hose 6d for sending air under pressure is connected between the air compressor 6c and the tank 6b.

A flow rate adjusting valve 6e is attached in the middle of the air hose 6d, and the simulated cement milk as a substitute solution for the cement milk discharged from each rotary shaft 3a into the simulated soil by adjusting the air pressure. The amount can be adjusted. Further, the air hose 6d is branched on the way and connected to a pressure gauge (not shown) so that the air pressure can be measured.

Next, a test method based on the simulated ground test apparatus 1 having the configuration of the embodiment of the present invention will be described below. For example, about 300 kg of transparent simulated soil (concentration 3.5%: 5.25 kg of chitosan, 5.25 kg of lactic acid, 289.5 kg of hot water (40 ° C)) composed of an aqueous solution as a substitute for the soft soil of the first embodiment is placed in the experimental tank 2. Leave it for 1-2 days, and wait for bubbles to escape from the transparent simulated soil consisting of an aqueous solution.

An external force is applied to the transparent simulated soil consisting of the aqueous solution from which air bubbles have been removed, by using the model agitator 3 provided on the upper part of the experimental tank 2. That is, the stirring motor 3j, the lifting motor 4e, the air compressor 6c, etc. of the simulated ground test apparatus 1 are operated.

When the agitating motor 3j of the model agitator 3 is operated, the rotational driving force of the agitating motor 3j is reduced by the speed reducer 3.
It is transmitted to the distributor 3h via i, and is divided into two by the distributor 3h to rotate and drive the two rotary shafts 3a.

When the raising / lowering motor 4e is operated, the rotational driving force of the raising / lowering motor 4e is changed to the pulley 4f.
Screw rod 4 through timing belt 4g and pulley 4f
Then, the screw rod 4d is rotated in one direction. When the screw rod 4d rotates in one direction, the elevator board 4b, through which the screw rod 4d is threaded, descends at a constant speed due to the screw movement. The model stirrer 3 is attached downward to the descending elevator 4b, and the tip ends of the two rotating shafts 3a of the model stirrer 3 which rotate rotate inside the transparent simulated soil consisting of an aqueous solution as a substitute for soft soil. Immerse yourself at a constant speed.

A plurality of stirring blades 3b are provided on the tip side surfaces of the two rotating shafts 3a which are immersed in the transparent simulated soil at a constant speed. The plurality of stirring blades 3b are transparent. Stir the inside of the simulated soil.

When the model agitator 3 is immersed in the transparent simulated soil, the air compressor 6c is activated. When the air compressor 6c operates, the compressed air is pressure-fed through the air hose 6d and fed into the tank 6b to increase the pressure in the tank 6b.

When the pressure in the tank 6b increases, the tank 6
The simulated cement milk, which is a solution as a substitute for the cement milk stored in b, is pressure-fed through the transport passage 6a by the pressure thereof and passes through the connector 6 and the rotary shafts 3
It flows into the hollow inside of a and is discharged from the lower discharge hole 3d and the upper discharge hole 3e into the agitated transparent simulated soil.

The state is shown by the transparent plates 2b on the four sides of the experimental tank 2.
Can be visually observed from the outside through the inside, and if necessary, the inside condition of the simulated soil is recorded on the video television.

In this case, the simulated cement milk discharged into the transparent simulated soil is colored, and the state of the simulated cement milk discharged into the stirred transparent simulated soil is changed to be transparent. Visual comparison can be made accurately in comparison with simulated soil.

2 for the simulated cement milk that is colored
There are various types, one is that the color disappears immediately in the transparent simulated soil, and the other is that the color does not disappear. It is used properly according to the purpose of the test.

For example, when using a simulated cement milk whose color disappears immediately after being discharged onto a transparent simulated soil, it is used for a test for knowing the performance of the model agitator 3 which stirs the simulated cement milk while discharging it. Since the color disappears immediately, there is an advantage that the test can be continued without changing the simulated soil.

That is, the performance of the stirring blades 3b and the tip blades 3c on the tip side of the model agitator 3 when the simulated cement milk is stirred while being discharged, that is, the trajectory of the discharged simulated cement milk during stirring. Meanwhile, it is possible to see whether or not it is being discharged into the simulated soil.

The function of the stirring blades 3b and the tip blades 3c of the model stirrer 3, that is, how these blades 3b and 3c work during stirring to diffuse the simulated cement milk to be discharged into the simulated soil. Can be seen.

When the simulated cement milk whose color does not disappear is used, the shape of the simulated cement milk discharged into the simulated soil can be visually observed. In other words, it can be used for a test to know what the shape of the pile will be when making a pile in the soil.

As a method of reinforcing soft ground, columnar piles (pile) are driven into the soft ground to strengthen the supporting ground, and cement milk is injected into the soft ground to harden the soil and the ground is hardened. There are methods to build and strengthen piles, which are used for this latter test.

The above-mentioned simulated cement milk is prepared by adding a colorant consisting of an aqueous solution to powdered sodium alginate. A simulated cement milk is prepared by adding 1% to 5% of a colorant composed of an aqueous solution described below to 1 part of powdered sodium alginate. The viscosity of the simulated cement milk is adjusted by adjusting the addition amount of the colorant composed of the aqueous solution.

The colorant in which the color of the simulated cement milk disappears is made from powdered phenolphthalein to which an aqueous solution of sodium hydroxide is added in a ratio of 1: 1.
The color is red and disappears immediately in simulated soil.

The colorant in the case where the color of the simulated cement milk does not fade is made from powdered methyl orange plus water in a ratio of 1: 1. The color is red.

By the way, since the model test results using the simulated cement milk, the simulated soil and the model agitator 3 are different from the actual test results of the actual cement milk, the soft soil and the agitator, the relationship of the similarity rule is used for correction. It will be used at the actual site.

Information necessary for the difference between the model test and the actual machine test is the excavation speed V of the stirrer (that is, the descending speed into the soil) and the rotation torque T of the stirrer in the soil. And the rotation torque T are derived using a similarity rule.

The excavation speed V ₁ of the model agitator 3 is obtained by the following equation using the similarity rule. π = F _i / F _c = (ρ ₀ V ₀ ² ) / c ₀ = (ρ ₁ V ₁ ² ) / c ₁ ─── where F _i is inertial force, F _c is adhesive force, and ρ ₀ is The actual density V ₀ of the soft soil is the excavation speed of the stirrer of the actual machine, c ₀ is the adhesive stress ρ ₁ of the soft soil of the actual machine, the density of the simulated soil in place of the soft soil, and c ₁ is the adhesive stress formula of the simulated soil, Actual density of soft soil ρ ₀ , adhesive stress c ₀
And the digging speed V ₀ of the actual stirrer is known,
Substitute each value into the expression. On the other hand, the density ρ ₁ and the adhesive stress c ₁ of the simulated soil in the model test can be obtained by the test. Therefore, the excavation speed V ₁ of the model agitator 3 in the model test can be obtained.

The rotation torque T ₁ of the model agitator 3 is obtained by the following equation using the similarity rule. T ₁ / T ₀ = (L ₁ / L ₀ ) ³ ─────────────── where T ₀ is the rotation torque of the actual agitator and L ₀ is the dimensions of the actual agitator. L ₁ in the dimension type model stirrer 3, the rotational torque T ₀ of actual agitator, since the size L ₁ of the size of the actual agitator L ₀ and model agitator 3 is known, and substituting respective values in the equation, The rotation torque T ₁ of the model agitator 3 in the model test is obtained.

By using the values of the excavation speed V ₁ and the rotation torque T ₁ of the model agitator 3 in the model test obtained from the above formula, a test is conducted by the simulated ground test apparatus 1, and an agitator of an actual machine is used. Depending on the diffusion state of cement milk in the soil when an external force is applied to the soft ground (when the inside of the soft soil is agitated) at the excavation speed V ₀ and the rotation torque T ₀ , and the action of the agitating blades and tip blades of the agitator. It is possible to estimate the movement of soft soil that is agitated.

On the contrary, the simulated ground test apparatus 1 is used to create the ideal function of the stirring blades and tip blades of the stirrer or the diffusion state of cement milk in the soil, and the digging speed V ₁ of the model stirrer 3 at that time is created. And the values of the rotational torque T ₁ are obtained in advance, and conversely from these values, the values of the excavation speed V ₀ and the rotational torque T ₀ of the actual stirrer are obtained using the above formulas, and these values are actually calculated at the actual site. It can also be used for construction.

The present invention is not limited to the embodiments of the present invention described above, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0066]

As is apparent from the above description, according to the transparent simulated soil as a substitute for the soft soil according to the invention of claims 1 to 5, a transparent simulated soil can be obtained as a substitute for the soft soil. By using this transparent simulated soil, what could not be three-dimensionally visible from the outside until now, the inside of the transparent simulated soil as a substitute for soft soil when external force was applied by a stirrer It is possible to externally and visually observe the state from outside at any time.

According to the ground test method for the inside of the soft soil using the transparent simulated soil as a substitute for the soft soil according to the invention of claim 6, the use of this transparent simulated soil allows the three-dimensional appearance from the outside. What was not visible to the outside, the internal state of the transparent simulated soil as a substitute for the soft soil when external force was applied by a stirrer can be visually observed from the outside at any time in three dimensions, and a transparent simulation It is possible to estimate the internal state of soft soil from the similarity rule between soil and soft soil.

Moreover, when the state in which the simulated cement milk is discharged into the simulated soil can be visually observed three-dimensionally at any time, and when the columnar pile is made in the soil by injecting the cement milk into the soft ground and hardening it Moreover, it is possible to estimate the shape of cement milk formed in the soil, and through this, an effective cement milk injection construction method can be obtained.

Further, it is possible to estimate how the shapes of the stirring blade and the tip blade of the stirrer function in the soft ground through this visual observation, and it is possible to estimate the shape of the stirring blade and the tip blade of the stirrer having higher performance. It can be used when inventing the shape, and can also perform an estimation performance test of the shape of the stirring blade or the tip blade of the invented stirrer.

Further, in the case of the structure of claim 7, the test can be continuously performed without changing the transparent simulated soil.

Further, in the case of the structure of claim 8, it can be utilized when estimating in what shape cement milk is formed in the soil.

[Brief description of drawings]

FIG. 1 is a diagram showing an actual torque change of soft soil measured by a vane tester.

FIG. 2 is a diagram showing a torque change of a chitosan aqueous solution measured by a vane tester.

FIG. 3 is a schematic perspective view of the simulated ground test apparatus showing the embodiment of the present invention with a part thereof omitted.

FIG. 4 is a front view of the upper side of the simulated ground test apparatus showing the embodiment of the present invention.

FIG. 5A is a front view of an experimental tank showing an embodiment of the present invention. (B) is a side view of the experimental tank showing the embodiment of the present invention. (C) is a plan view of an experimental tank showing an embodiment of the present invention.

FIG. 6 is a partially enlarged front view of the tip side of the model stirrer showing the embodiment of the present invention.

[Explanation of symbols]

1 Simulated ground test equipment 2 experimental tanks 2a frame 2b transparent plate 2c outlet 2d diagonal 3 model stirrer 3a rotating shaft 3b Stirrer 3c Tip wing 3d Lower discharge hole 3e Upper discharge hole 3f excavation wing 3g horizontal connecting rod 3h distributor 3i reducer 3j Stirring motor 4 Support mechanism 4a support frame 4b Lifting board 4c guide 4d screw rod 4e Lifting motor 4f pulley 4g timing belt 4h counterweight 4i rope 4j roller 5 Torque detector 6 connectors 6a Transportation passage 6b tank 6c air compressor 6d air hose 6e Flow control valve

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01N 33/24 JISST file (JOIS)

Claims (8)

(57) [Claims] 1. 2% to 5% obtained by mixing chitosan and a solvent at a weight ratio of 1: 1 in hot water having a predetermined water temperature and stirring.
A transparent simulated soil as a substitute for soft soil characterized by comprising a transparent aqueous solution having a concentration of. 2. The solvent is lactic acid, and the water temperature of hot water is 40 ° C.
The transparent simulated soil as a substitute for the soft soil according to claim 1. 3. The transparent simulated soil as a substitute for the soft soil according to claim 1, wherein the hot water has a water temperature in the range of 30 ° C. to 90 ° C. 4. The transparent simulated soil as a substitute for the soft soil according to claim 1, wherein the solvent comprises an organic acid such as succinic acid, citric acid or acetic acid. 5. The transparent simulated soil as a substitute for the soft soil according to claim 1, wherein the solvent comprises an inorganic acid such as phosphoric acid, hydrochloric acid, sulfuric acid or polymerized phosphoric acid. 6. A model simulated stirrer similar to an actual stirrer is converted by a similar rule from the upper side of the experimental tank to the downward direction, by placing the transparent simulated soil as a substitute for the soft soil of claim 1 in the experimental tank having a transparent side surface. While being driven with a predetermined torque, it is lowered at a predetermined speed converted by the similarity law to be immersed in the simulated soil, and the colored simulated cement is used as a substitute for the cement milk from the tip side of the model agitator immersed in the simulated soil. A method for testing the ground inside soft soil using transparent simulated soil as a substitute for soft soil, characterized in that milk is discharged and the movement inside the simulated soil is visually observed from outside at any time. 7. The ground test method for the inside of soft soil using transparent simulated soil as a substitute for the soft soil according to claim 6, wherein the colored simulated cement milk disappears in the simulated soil. 8. The method for testing the ground inside soft soil using transparent simulated soil as a substitute for the soft soil according to claim 6, wherein the colored simulated cement milk does not disappear in the simulated soil.