JP6664704B2 - Method and apparatus for evaluating plastic fluidity of excavated soil in chamber in earth pressure shield method, and earth pressure shield excavator - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method and an apparatus for evaluating plastic flowability of excavated soil in a chamber in an earth pressure shield construction method, and an earth pressure shield excavator.

  BACKGROUND ART Conventionally, an earth pressure type shield construction method applied to shield tunnel construction is known. This method uses an earth-pressure shield excavator equipped with a chamber for taking in excavated soil behind the cutter device. The excavated soil taken in the chamber is exposed to chemicals such as hydrobentonite and polymer materials or air bubbles. Is added to the excavated soil and agitated by an agitating blade, whereby the excavated soil has a predetermined plastic fluidity, and the earth pressure is applied to the face to excavate while maintaining the face stably.

  In this earth pressure shield method, it is important that the earth pressure from the excavated soil acts uniformly and stably on the entire face of the face, so that the plastic fluidity of the excavated soil in the chamber is appropriately set and stabilized. Need to be maintained. For that purpose, it is necessary to sequentially confirm whether or not the excavated soil is uniformly plastically fluidized in the entire chamber during excavation. In particular, in recent years, with the enlargement of the earth pressure shield method, the need to evaluate the plastic fluidity of excavated soil in a chamber is increasing. As a conventional method for evaluating the plastic fluidity of excavated soil, for example, those disclosed in Patent Documents 1 to 3 are known.

  Patent Document 1 is a method for qualitatively determining the plastic fluidity of excavated soil from the torque of a rotating body installed in a chamber, and cannot quantitatively evaluate the plastic fluidity.

  Patent Literature 2 and Patent Literature 3 quantitatively evaluate the plastic flow property and flow direction of excavated soil from the torque of a rotating body installed in a chamber and preliminarily analytically estimate the plastic flow state in the chamber. It is a method of managing the construction by comparing. Since this method is an evaluation method using a special rotating device, there is a high possibility that a failure will occur. The analysis here is based on the premise that a conventional numerical analysis method (for example, a difference method, FEM, DEM, or the like) is used. A phenomenon may occur, which may cause a failure in the analysis.

  On the other hand, the present inventors have disclosed Patent Document 4 and Patent Document 5 (Japanese Patent Application No. 2015-141743), Patent Document 6 (Japanese Patent Application No. 2005-052282) and Patent Document 7 (Japanese Patent Application No. 2015-136399) which have not been disclosed at this time. No.) has already been proposed.

  Patent Literature 4 and Patent Literature 5 are methods for indirectly evaluating the plastic fluidity of excavated soil from the fluctuation state of the earth pressure gauge, and do not directly evaluate the excavated soil. Patent Document 6 is a method for quantitatively evaluating the plastic fluidity of excavated soil from the torque of a rotating body installed in a chamber. Since this method is an evaluation method using a special rotating device as in the above-mentioned Patent Documents 2 and 3, it cannot be said that there is no risk of an increase in development / installation cost of the device or occurrence of a failure.

  Patent Literature 7 is a method of estimating a stirring flow state in a chamber by a particle method analysis (MPS analysis). According to this method, even if the analysis target is a fluid having high viscosity and large deformation such as excavated soil, the plastic flow state can be numerically and stably analyzed. However, since it is necessary to assume plastic fluidity (plastic viscosity, yield value, etc.) of the excavated soil as an analysis parameter, there is a problem in the application method.

JP 2003-97181 A JP 2005-90174 A JP 2007-191878 A JP 2014-9545 A

  Therefore, there has been a demand for the development of a technology capable of stably directly estimating the plastic fluidity (plastic viscosity, yield value, etc.) of excavated soil without using a special device.

  The present invention has been made in view of the above, a method for evaluating the plastic fluidity of an excavated soil in a chamber in an earth pressure shield method capable of stably directly estimating the plastic fluidity of an excavated soil, an evaluation device, and An object of the present invention is to provide an earth pressure shield excavator.

  In order to solve the above-described problems and achieve the object, a method for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention includes a stirring blade installed on a cutter spoke side and the cutter spoke. The excavated soil in the chamber is agitated by an agitator that is independently driven to rotate to impart plastic fluidity to the excavated soil, and the excavated soil is subjected to earth pressure to exert the excavation while stabilizing the face. Applied to the earth pressure type shield method, is an evaluation method for evaluating the plastic flowability of the excavated soil in the chamber, and expresses the excavated soil as a collection of particles, and analyzes the movement of the particles by calculation On the other hand, the shape of the inside of the chamber for stirring the excavated soil is approximated by a polyhedron, and An analysis model in which the stirring blade and the agitator are represented by a movable wall is created, and the analysis is performed by creating a rigid body by a wall in which a virtual repulsive force is generated in which a repulsive force is generated so that particles do not pass. A flow analysis step of performing a flow analysis of the excavated soil in the model, and a flow analysis by the flow analysis step using the plastic fluidity of the excavated soil as a parameter to calculate an analysis value of torque generated in the agitator in the analysis model The torque analysis value calculation step to be performed, the measured value of the torque generated in the agitator obtained at the time of construction, and comparing the analysis value of the torque calculated by the torque analysis value calculation step, the torque corresponding to the measured value of the torque Evaluation to evaluate the plastic fluidity of the excavated soil in the analysis model as the plastic fluidity of the excavated soil during construction Characterized in that it comprises a degree.

  Further, in another earth pressure type shield method according to the present invention, the method for evaluating the plastic fluidity of excavated soil in a chamber in the above-described invention is characterized in that the evaluation step includes determining at least one of a slump value and a slump flow value by determining the plasticity of the excavated soil. It is characterized by being evaluated as liquidity.

  Further, the plastic fluidity evaluation device for excavated soil in the chamber in the earth pressure type shield method according to the present invention, the stirring blade installed on the cutter spoke side and the agitator that is driven to rotate independently of the cutter spoke, the inside of the chamber. The excavated soil is agitated to impart plastic fluidity to the excavated soil, and is applied to an earth pressure type shield method for excavating while stabilizing the face by applying the earth pressure of the excavated soil to the face. An evaluation device for evaluating the plastic fluidity of the excavated soil, wherein the excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method for analyzing the movement of the particles by calculation. The shape inside the chamber to be stirred is approximated by a polyhedron, and a repulsive force is generated so that the particles do not pass through the surface forming the polyhedron. A rigid body is formed by a wall having a distributed repulsive force, and an analytical model is created in which the stirring blade and the agitator are represented by movable walls, and a flow analysis of the excavated soil in the created analytical model is performed. Flow analysis means, performing a flow analysis by the flow analysis means using the plastic fluidity of the excavated soil as a parameter, torque analysis value calculation means for calculating the analysis value of the torque generated in the agitator in the analysis model, at the time of construction By comparing the obtained measured value of the torque generated in the agitator with the analyzed value of the torque calculated by the torque analysis value calculating means, the plastic fluidity of the excavated soil in the analysis model corresponding to the measured value of the torque is obtained. And an evaluation means for evaluating the excavated soil as plastic fluidity during construction.

  In addition, in the above-described invention, the evaluation means may determine at least one of a slump value and a slump flow value of the excavated soil according to another earth pressure type shield method according to the present invention. It is characterized by being evaluated as liquidity.

  Further, the earth pressure shield excavator according to the present invention is configured to agitate the excavated soil in the chamber by using an agitator installed on the cutter spoke side and an agitator that is driven to rotate independently of the cutter spoke. An earth-pressure shield excavator that imparts plastic fluidity and excavates while stabilizing the face by applying the earth pressure of the excavated soil to the face, and the plasticity of the excavated soil in the chamber in the above-described earth-pressure shield construction method It is characterized by having a liquidity evaluation device.

  According to the plastic fluidity evaluation method of the excavated soil in the chamber in the earth pressure type shield method according to the present invention, the stirring blades installed on the cutter spoke side and the agitator that is driven to rotate independently of the cutter spokes, the inside of the chamber. The excavated soil is agitated to impart plastic fluidity to the excavated soil, and is applied to an earth pressure type shield method for excavating while stabilizing the face by applying the earth pressure of the excavated soil to the face. An evaluation method for evaluating the plastic fluidity of the excavated soil, wherein the excavated soil is expressed as a set of particles, and the movement of the particles is analyzed by a particle method for analysis by calculation. The shape inside the chamber to be stirred is approximated by a polyhedron, and a repulsive force is generated so that the particles do not pass through the surface forming the polyhedron. A rigid body is formed by a wall having a distributed repulsive force, and an analytical model is created in which the stirring blade and the agitator are represented by movable walls, and a flow analysis of the excavated soil in the created analytical model is performed. Flow analysis step, the flow analysis by the flow analysis step using the plastic fluidity of the excavated soil as a parameter, a torque analysis value calculation step of calculating an analysis value of the torque generated in the agitator in the analysis model, during construction By comparing the obtained measured value of the torque generated in the agitator with the analyzed value of the torque calculated in the torque analysis value calculating step, the plastic fluidity of the excavated soil in the analysis model corresponding to the measured value of the torque is obtained. And evaluating the plastic fluidity of the excavated soil at the time of construction, the torque of the agitator By measuring an effect that can be estimated stably directly the plastic flow of the excavated soil without using a special apparatus.

  Further, according to the method for evaluating the plastic fluidity of excavated soil in a chamber in another earth pressure type shield method according to the present invention, the evaluation step includes determining at least one of a slump value and a slump flow value as plastic fluidity of the excavated soil. Since the evaluation is performed, the plastic flow state of the excavated soil in the chamber can be managed by using an index such as a slump value or a slump flow value.

  Further, according to the plastic fluidity evaluation device for excavated soil in the chamber in the earth pressure shield method according to the present invention, the chamber is provided with an agitator that is installed on the cutter spoke side and an agitator that is driven to rotate independently of the cutter spoke. The excavated soil is agitated to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is applied to the face to stabilize the face by applying the earth pressure type shield method, and the chamber is applied to the earth pressure type shield method. An evaluation device for evaluating the plastic fluidity of the excavated soil in a vessel, wherein the excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method, and the excavation soil is subjected to analysis. The shape inside the chamber for stirring the soil is approximated by a polyhedron, and a repulsive force is generated so that the particles do not pass through the surface forming the polyhedron. A rigid body is formed by a wall in which a virtual repulsive force is distributed, and an analysis model is created in which the stirring blade and the agitator are represented by movable walls, and a flow analysis of the excavated soil in the created analysis model is performed. Flow analysis means to perform, the flow analysis by the flow analysis means as a parameter plastic flowability of the excavated soil, torque analysis value calculation means to calculate the analysis value of the torque generated in the agitator in the analysis model, By comparing the measured value of the torque generated in the agitator obtained at the time of construction with the analyzed value of the torque calculated by the torque analysis value calculating means, the plasticity of the excavated soil in the analysis model corresponding to the measured value of the torque is compared. Fluidity, evaluation means for evaluating the plastic fluidity of the excavated soil at the time of construction, since it comprises an agitator By measuring the torque, an effect that can be estimated stably directly the plastic flow of the excavated soil without using a special apparatus.

  Further, according to the plastic fluidity evaluation device for excavated soil in the chamber in another earth pressure shield method according to the present invention, the evaluation means, slump value, at least one of the slump flow value as the plastic fluidity of the excavated soil. Since the evaluation is performed, the plastic flow state of the excavated soil in the chamber can be managed by using an index such as a slump value or a slump flow value.

  Further, according to the earth pressure shield excavator according to the present invention, the excavated soil in the chamber is agitated by the agitating blade installed on the cutter spoke side and the agitator which is driven to rotate independently of the cutter spoke. An earth-pressure shield excavator that imparts plastic fluidity to soil and excavates while stabilizing the face by applying the earth pressure of the excavated soil to the face, wherein the excavated soil in the chamber in the above-described earth pressure shield method is used. Is provided, there is an effect that it is possible to provide an earth-pressure shield excavator capable of stably directly estimating the plastic fluidity of excavated soil.

FIG. 1 is a schematic side sectional view of a cutter face portion to which a method and an apparatus for evaluating plastic flowability of excavated soil in a chamber in an earth pressure shield method according to the present invention and an earth pressure shield excavator are applied. FIG. 2 is a schematic flowchart showing an embodiment of a method and an apparatus for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention. FIG. 3 is a diagram illustrating an example of an analytical model of a plastic fluidity evaluation method of an excavated soil in a chamber and an evaluation device in an earth pressure type shield method according to the present invention. FIG. 4 is a diagram illustrating an example of a method of comparing a torque measurement value and a torque analysis value according to the present invention. FIG. 5 is a diagram showing an example of a method for estimating a slump value and a slump flow value according to the present invention. FIG. 6 is a schematic configuration diagram showing an embodiment of a plastic fluidity evaluation device for excavated soil in a chamber in the earth pressure shield method according to the present invention.

  Hereinafter, embodiments of a method, an evaluation device, and an earth pressure shield excavator for evaluating the plastic fluidity of excavated soil in a chamber in an earth pressure shield method according to the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

[Evaluation method of plastic fluidity of excavated soil in chamber in earth pressure type shield method]
First, a method for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention will be described.

  The plastic fluidity evaluation method of the excavated soil in the chamber in the earth pressure type shield method according to the present invention, the excavated soil is agitated by a stirring blade and an agitator installed in the chamber to impart plastic fluidity to the excavated soil. This method is applied to the earth pressure shield method in which excavated soil is excavated while stabilizing the face by applying the earth pressure to the face, and is an evaluation method for evaluating the plastic fluidity of the excavated soil in the chamber.

  FIG. 1 is a schematic side sectional view in which a cutter face portion of an earth pressure type shield excavator is enlarged. As shown in this figure, a shield machine 10 of an earth pressure type shield excavator includes a cutter face 10 in order to enhance the stirring effect of excavated soil 18 in a chamber 16 defined by a back surface of a cutter face 12 and a partition wall 14. A plurality of stirring blades 22 protruding into the chamber 16 are fixed to the cutter spokes 20 on the back surface of the twelve. In the example of the figure, an example in which two portions are fixed above and below the rotating shaft 24 for convenience of description is shown, but the present invention is not limited to this. That is, the installation position of the stirring blade 22 may be arbitrarily set so that an effective stirring effect on the excavated soil can be obtained in the entire chamber 16, and it is better to displace both positions slightly in the radial direction. It is more preferable because the stirring can be performed over a wide range throughout. When the cutter face 12 rotates around the rotation axis 24 during excavation, the stirring blade 22 on the back also rotates around the rotation axis 24 in conjunction with this rotation, and is taken into the chamber 16 formed between the shield face 10 and the stirring machine 22. Stir the excavated soil.

  An agitator 26 protruding into the chamber 16 is provided on the outer peripheral surface of the rotating shaft 24. The agitator 26 is driven to rotate independently of the cutter face 12 (cutter spoke 20) by a drive motor 28 provided outside the partition 14. A torque measuring device 30 for measuring the rotational torque of the agitator 26 is provided near the drive motor 28. Since the rotational torque of the agitator 26 is proportional to the current value supplied to the drive motor 28, the torque can be calculated by measuring the current value of the drive motor 28.

  Next, a specific procedure of the plastic fluidity evaluation method according to the present invention will be described.

  FIG. 2 is a schematic flowchart of the plastic fluidity evaluation method according to the present invention. As shown in this figure, in the plastic fluidity evaluation method of the present invention, an analysis model that models an excavated soil and a stirring mechanism is created in advance before construction (step S1). Here, excavated soil, which is a high-viscosity fluid, is expressed as a group of particles, and is modeled as an analysis target of a particle method for analyzing the movement of the particles by calculation. In this case, the excavated soil can be modeled with a Bingham fluid where the physical properties of the fluid are described by the yield value and the plastic viscosity. In this modeling, in order to speed up the flow analysis, the Bingham fluid may be handled by an equivalent linear approximation in which the fluid becomes a viscoplastic fluid when flowing, and becomes a high viscous fluid when immobile.

  In addition, the shape of the chamber 16 for stirring the excavated soil is approximated by a polygon (polyhedron), and the surface forming the polygon is a rigid body formed by a wall in which a virtual repulsive force that generates a repulsive force so that particles do not pass is distributed. Create an analysis model. Here, the portion of the outer wall forming the chamber 16 is represented by a fixed polygon wall, and the stirring blade 22 and the agitator 26 are represented by a moving polygon wall (moving wall). The moving polygon wall is rotatable about a rotation axis 24. FIG. 3 shows an example of the analysis model of the actual machine created in this way. In this figure, the chamber is viewed from the inside of the pit, and illustration of a steel shell portion such as a partition wall 14 of the shield machine 10 and excavated soil is omitted.

  Next, the flow analysis of the plastic flow state of the excavated soil in the created analysis model is performed using a computer (flow analysis step: step S2). As an analysis method, an implicit method that can stably analyze even a high-viscosity fluid is used.

  In this flow analysis step, a parameter study is carried out assuming various plastic flow states of the excavated soil using the plastic flowability (plastic viscosity, yield value) of the excavated soil as a parameter. Subsequently, the analysis value of the torque generated in the agitator in the analysis model is calculated based on the parameter study (torque analysis value calculation step: step S3).

  By such pre-analysis prior to construction, an analysis result as shown on the left side of FIG. 4, for example, is obtained. In the analysis results, torque analysis values of the agitator are shown in a table format corresponding to various combinations of assumed plastic viscosity and yield value.

  Next, the measured value of the torque generated in the agitator obtained at the time of construction is compared with the analyzed value of the torque calculated in the torque analysis value calculating step of step S3 (step S4), and the analysis corresponding to the measured value of the torque is performed. The plastic fluidity of the excavated soil in the model is evaluated as the plastic fluidity of the excavated soil in the chamber during construction (evaluation step: step S5).

  In this case, for example, the torque of the agitator 26 is measured by the torque measuring device 30 while rotating the cutter and the agitator 26. Then, the torque measurement value is compared with the torque analysis value in the analysis result table on the left side of FIG. 4 to search for a torque analysis value having a high degree of agreement with the torque measurement value, and the plastic viscosity corresponding to the torque analysis value is determined. Find the yield value. The example of FIG. 4 shows a case where the measured torque value B2 at the time of construction matches the torque analysis value B2 in the table. In this case, the plastic viscosity corresponding to the torque analysis value B2 is estimated to be 60 Pa · s, and the yield value is estimated to be 600 Pa.

  In order to increase the collation efficiency, it is desirable to obtain an analysis result in which the parameter increment is made fine in the above parameter study. Alternatively, the relationship between the torque analysis value and the plastic viscosity, the yield value is defined by an interpolation formula or an approximate curve formula, and the plastic viscosity corresponding to the torque measurement value and the yield value are calculated using these formulas. Is also good. If these verification and calculation processes are systematized by a computer program in advance, further labor savings can be achieved.

  It is desirable that the plastic fluidity of the excavated soil evaluated in this way be visualized and displayed on a computer display or the like as necessary. In this way, the user can continuously and accurately grasp the plastic fluidity of the excavated soil in the chamber 16 in real time by monitoring the contents displayed on the display when the cutter is rotating or when the cutter is stopped. Excavation can be performed while performing appropriate construction management such as injection management of additive materials (mud material, foam material, etc.). For this reason, management of plastic fluidity can be performed with high accuracy.

  As described above, according to the present embodiment, by measuring the torque of the agitator, the plastic fluidity of the excavated soil can be directly estimated stably without using a special device.

  In the flow analysis step of the present invention, an implicit method that can stably analyze even a fluid having a high viscosity, and a particle method that does not break the analysis grid even when the fluid is greatly deformed are adopted. Therefore, according to the present invention, it is possible to stably analyze even a fluid having high viscosity and large deformation such as excavated soil. Thereby, the plastic fluidity of the excavated soil can be stably evaluated.

  Further, according to the flow analysis step of the present invention, not only the pressure but also the speed and shear rate of the excavated soil as a fluid can be obtained, and the plastic fluidization index can be obtained by the plastic flow function. Further, by treating the polyhedral polygon wall as an elastic body instead of a rigid body, it is possible to calculate deformation and stress due to pressure caused by the fluid, and to evaluate and design a member deformation due to excavation. Naturally, the plastic fluidity of the excavated soil in the chamber at full scale can be evaluated by taking the size effect of the fluid into account.

In the above embodiment, it is also possible to estimate a slump value, a slump flow value, and the like from a plastic viscosity and a yield value by, for example, a method described in Reference 1 below. FIG. 5 is an example of an estimation method using FIG. 10 (the relationship between a flow value and a slump value and a rheological constant) described in Reference Document 1 below. For example, if the plastic viscosity of the excavated soil evaluated in the above embodiment is 60 Pa · s and the yield value is 600 Pa, in this figure, η = 0.06 kPa · s (= 60 Pa · s), τ _y By obtaining the intersection of the lines of = 6 gf / cm ² (= 600 Pa), the slump value can be estimated to be about 20 cm. In this way, if the relationship between the plastic viscosity and the yield value, the slump value, and the slump flow value is grasped in advance, the slump value and the slump flow value can be calculated by applying the evaluated plastic viscosity and the yield value to this relationship. Can be estimated.

  [Reference 1] Yasuo Tanikawa, Hiroshi Mori, Kazuhito Tsutsui, Yoshiyuki Kurokawa: "Measurement of rheological constant of fresh concrete by slump test and slip resistance test", Proc. Of the 8th Annual Conference of Japan Concrete Institute, pp. 381 -384, Fig. 10, 1986

  As described above, according to the above-described embodiment, the plastic flow state of the excavated soil in the chamber can be managed by an index such as “plastic viscosity, yield value”, or “slump value, slump flow value”. . Since such an index can be used as an index for controlling the amount of additive material (such as mud material, foam material) at the time of construction, it contributes to rationalization of construction management and labor saving.

[Evaluation system for plastic fluidity of excavated soil in chamber in earth pressure shield method]
Next, an apparatus for evaluating the plastic flowability of excavated soil in a chamber in the earth pressure shield method according to the present invention will be described.

  As shown in FIG. 6, the apparatus 40 for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention is a method for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention. Is realized as an apparatus, and includes an analysis model creation unit 42, a flow analysis unit 44, a torque analysis value calculation unit 46, an evaluation unit 48, and a visualization unit 50.

  The analysis model creation means 42 creates an analysis model in which the excavated soil and the stirring mechanism are modeled, and can be constituted by a computer having a CPU. More specifically, the analysis model creation means 42 expresses the excavated soil, which is a high-viscosity fluid, as a collection of particles, and models the excavated soil as an analysis target of a particle method for analyzing the movement of the particles by calculation. In this case, the excavated soil can be modeled with a Bingham fluid where the physical properties of the fluid are described by the yield value and the plastic viscosity. In this modeling, in order to speed up the flow analysis, the Bingham fluid may be handled by an equivalent linear approximation in which the fluid becomes a viscoplastic fluid when flowing, and becomes a high viscous fluid when immobile.

  The analysis model creating means 42 approximates the shape of the chamber 16 for stirring the excavated soil with a polygon (polyhedron) and distributes a virtual repulsive force that generates a repulsive force so that particles do not pass through the surface of the polygon. Create an analysis model that is a rigid body with the wall that has been made. Here, the portion of the outer wall forming the chamber 16 is represented by a fixed polygon wall, and the stirring blade 22 and the agitator 26 are represented by a moving polygon wall (moving wall). The moving polygon wall is rotatable about a rotation axis 24.

  The flow analysis means 44 performs flow analysis of the plastic flow state of the excavated soil in the analysis model created by the analysis model creation means 42, and can be constituted by a computer having a CPU. In addition, as an analysis method, an implicit method that can stably analyze even a high-viscosity fluid is used.

  The torque analysis value calculation means 46 calculates the analysis value of the torque generated in the agitator in the analysis model by a parameter study using the flow analysis means 44 using the plastic fluidity (plastic viscosity, yield value) of the excavated soil as a parameter. Things. The torque analysis value calculating means 46 is executed as a pre-analysis prior to the construction, thereby obtaining, for example, a table type torque analysis value as shown on the left side in FIG.

  The evaluation means 48 compares the torque measurement value of the agitator obtained at the time of construction with the torque analysis value calculated by the torque analysis value calculation means 46 to determine the plastic fluidity of the excavated soil in the analysis model corresponding to the torque measurement value. This is to evaluate the plastic fluidity of the excavated soil in the chamber during construction.

  In this case, for example, the torque of the agitator 26 is measured by the torque measuring device 30 while rotating the cutter and the agitator 26, and the torque is compared with a torque analysis value as shown on the left side of FIG. Then, a torque analysis value having a high degree of coincidence with the torque measurement value is searched, and a plastic viscosity and a yield value corresponding to the torque analysis value are obtained. As described above, in order to increase the collation efficiency, the relationship between the torque analysis value, the plastic viscosity, and the yield value is defined by an interpolation formula, an approximate curve formula, or the like, and the torque measurement value is calculated using these formulas. The plastic viscosity and the yield value may be calculated. If these verification and calculation processes are systematized by a computer program in advance, further labor savings can be achieved.

  Note that, as described above, the evaluation means 48 may estimate a slump value, a slump flow value, and the like from the plastic viscosity and the yield value, for example, by the method described in the above-mentioned Reference 1. In this case, if the process of estimating the slump value, the slump flow value, and the like from the plastic viscosity and the yield value is systematized in advance by a computer program or the like, further labor saving can be achieved.

  The visualization means 50 visualizes and displays the plastic fluidity of the excavated soil evaluated by the evaluation means 48, and can be constituted by, for example, a display. The user can monitor the plastic flow of the excavated soil in the chamber 16 accurately and continuously in real time by monitoring the contents displayed on the display when the cutter is rotating or stopped. It is possible to carry out excavation while performing appropriate construction management such as injection management of foam material. For this reason, management of plastic fluidity can be performed with high accuracy.

  As described above, according to the present embodiment, by measuring the torque of the agitator, the plastic fluidity of the excavated soil can be directly estimated stably without using a special device.

[Earth pressure shield excavator]
Next, an earth pressure shield excavator according to the present invention will be described.

  In the earth pressure type shield excavator according to the present invention, the excavated soil in the chamber 16 is agitated by the agitating blade 22 installed on the cutter spoke 20 side and the agitator 26 which is driven to rotate independently of the cutter spoke 20. An earth-pressure shield excavator that imparts plastic fluidity to the soil and excavates while stabilizing the face by applying the earth pressure of the excavated soil to the face, in the earth-pressure shield method according to the present invention described above. The apparatus is provided with a device 40 for evaluating plasticity and fluidity of excavated soil in a chamber. Therefore, according to the present embodiment, the same functions and effects as those described in the plastic fluidity evaluation device 40 can be obtained.

  As described above, according to the method for evaluating the plastic fluidity of excavated soil in a chamber in the earth pressure shield method according to the present invention, the stirring blades installed on the cutter spoke side and the cutter spoke are driven to rotate independently. The agitator stirs the excavated soil in the chamber to impart plastic fluidity to the excavated soil, and applies the earth pressure of the excavated soil to the face to apply it to the earth pressure shield method that excavates while stabilizing the face. An evaluation method for evaluating the plastic fluidity of the excavated soil in the chamber, wherein the excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method for analyzing the movement of the particles by calculation. On the other hand, the shape in the chamber for stirring the excavated soil is approximated by a polyhedron, and the particles do not pass through the surface forming the polyhedron. A resilient force is generated and a rigid body is formed by a wall in which a virtual repulsive force is distributed, and an analytical model in which the stirring blade and the agitator are represented by movable walls is created, and the excavated soil in the created analytical model is created. A flow analysis step of performing a flow analysis of the excavated soil, performing a flow analysis by the flow analysis step using the plastic fluidity of the excavated soil as a parameter, and calculating an analysis value of a torque generated in the agitator in the analysis model. And comparing the measured value of the torque generated in the agitator obtained at the time of construction with the analyzed value of the torque calculated in the torque analysis value calculating step, and performing the excavation in the analysis model corresponding to the measured value of the torque. The plastic fluidity of the soil, the evaluation step to evaluate as the plastic fluidity of the excavated soil during construction By measuring the torque of the agitator, it can be estimated stably directly plastic flow of no excavated soil using a special apparatus.

  Further, according to the method for evaluating the plastic fluidity of excavated soil in a chamber in another earth pressure type shield method according to the present invention, the evaluation step includes determining at least one of a slump value and a slump flow value as plastic fluidity of the excavated soil. Since the evaluation is performed, the plastic flow state of the excavated soil in the chamber can be managed by an index such as a slump value and a slump flow value.

  Further, according to the plastic fluidity evaluation device for excavated soil in the chamber in the earth pressure shield method according to the present invention, the chamber is provided with an agitator that is installed on the cutter spoke side and an agitator that is driven to rotate independently of the cutter spoke. The excavated soil is agitated to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is applied to the face to stabilize the face by applying the earth pressure type shield method, and the chamber is applied to the earth pressure type shield method. An evaluation device for evaluating the plastic fluidity of the excavated soil in a vessel, wherein the excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method, and the excavation soil is subjected to analysis. The shape inside the chamber for stirring the soil is approximated by a polyhedron, and a repulsive force is generated so that the particles do not pass through the surface forming the polyhedron. A rigid body is formed by a wall in which a virtual repulsive force is distributed, and an analysis model is created in which the stirring blade and the agitator are represented by movable walls, and a flow analysis of the excavated soil in the created analysis model is performed. Flow analysis means to perform, the flow analysis by the flow analysis means as a parameter plastic flowability of the excavated soil, torque analysis value calculation means to calculate the analysis value of the torque generated in the agitator in the analysis model, By comparing the measured value of the torque generated in the agitator obtained at the time of construction with the analyzed value of the torque calculated by the torque analysis value calculating means, the plasticity of the excavated soil in the analysis model corresponding to the measured value of the torque is compared. Fluidity, evaluation means for evaluating the plastic fluidity of the excavated soil at the time of construction, since it comprises an agitator By measuring the torque can be estimated stably directly plastic flow of no excavated soil using a special apparatus.

  Further, according to the plastic fluidity evaluation device for excavated soil in the chamber in another earth pressure shield method according to the present invention, the evaluation means, slump value, at least one of the slump flow value as the plastic fluidity of the excavated soil. Since the evaluation is performed, the plastic flow state of the excavated soil in the chamber can be managed by an index such as a slump value and a slump flow value.

  Further, according to the earth pressure shield excavator according to the present invention, the excavated soil in the chamber is agitated by the agitating blade installed on the cutter spoke side and the agitator which is driven to rotate independently of the cutter spoke. An earth-pressure shield excavator that imparts plastic fluidity to soil and excavates while stabilizing the face by applying the earth pressure of the excavated soil to the face, wherein the excavated soil in the chamber in the above-described earth pressure shield method is used. Therefore, an earth pressure type shield excavator capable of stably directly estimating the plastic fluidity of excavated soil can be provided.

  As described above, in the earth pressure type shield method according to the present invention, the method and apparatus for evaluating the plastic fluidity of excavated soil in the chamber, the earth pressure type shield excavator, excavation in the chamber by the stirring blade installed on the cutter spoke side. It is useful for the earth pressure type shield method in which the soil is stirred to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is applied to the face to stabilize the face and excavate while excavating. It is suitable for directly and stably estimating the plastic fluidity of the material.

DESCRIPTION OF SYMBOLS 10 Shield machine 12 Cutter face 14 Partition wall 16 Chamber 18 Excavated soil 20 Cutter spoke 22 Stirrer blade 24 Rotating shaft 26 Agitator 28 Drive motor 30 Torque measuring device 40 Plastic fluidity evaluation device 42 Analysis model creation means 44 Flow analysis means 46 Torque analysis value Calculation means 48 Evaluation means 50 Visualization means

Claims (5)

The excavated soil in the chamber is agitated by the agitating blade installed on the cutter spoke side and the agitator which is driven to rotate independently of the cutter spoke to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is increased. Applied to the earth pressure shield construction method to excavate while stabilizing the face by acting on the face, an evaluation method for evaluating the plastic fluidity of the excavated soil in the chamber,
The excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method for analyzing by calculation, while the shape of the chamber for stirring the excavated soil is approximated by a polyhedron, and this polyhedron is approximated. The surface that forms is a rigid body composed of walls in which a virtual repulsive force is generated in which a repulsive force is generated so that the particles do not pass, and an analysis model is created in which the stirring blade and the agitator are represented by movable walls. And, a flow analysis step of performing a flow analysis of the excavated soil in the created analysis model,
A torque analysis value calculation step of performing a flow analysis by the flow analysis step using the plastic flowability of the excavated soil as a parameter and calculating an analysis value of torque generated in the agitator in the analysis model,
The measured value of the torque generated in the agitator obtained at the time of construction and the analyzed value of the torque calculated in the torque analysis value calculating step are compared with each other, and the plasticity of the excavated soil in the analysis model corresponding to the measured value of the torque is compared. An evaluation step of evaluating fluidity as plastic fluidity of the excavated soil during construction. A method for evaluating plastic fluidity of excavated soil in a chamber in an earth pressure shield method.   The said evaluation process evaluates at least one of a slump value and a slump flow value as the plastic fluidity of the said excavated soil, The plastic fluidity evaluation of the excavated soil in a chamber in the earth pressure type shield method of Claim 1 characterized by the above-mentioned. Method. The excavated soil in the chamber is agitated by the agitating blade installed on the cutter spoke side and the agitator which is driven to rotate independently of the cutter spoke to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is increased. Applied to the earth pressure shield construction method of excavating while stabilizing the face by acting on the face, an evaluation device for evaluating the plastic fluidity of the excavated soil in the chamber,
The excavated soil is expressed as a collection of particles, and the movement of the particles is analyzed by a particle method for analyzing by calculation, while the shape of the chamber for stirring the excavated soil is approximated by a polyhedron, and this polyhedron is approximated. The surface that forms is a rigid body with a wall in which a virtual repulsive force is generated in which a repulsive force is generated so that the particles do not pass, and an analysis model is created in which the stirring blade and the agitator are represented by a movable wall that can move. And, flow analysis means for performing a flow analysis of the excavated soil in the created analysis model,
Torque analysis value calculation means for performing flow analysis by the flow analysis means using the plastic fluidity of the excavated soil as a parameter and calculating an analysis value of torque generated in the agitator in the analysis model,
By comparing the measured value of the torque generated in the agitator obtained at the time of construction with the analyzed value of the torque calculated by the torque analysis value calculating means, the plasticity of the excavated soil in the analysis model corresponding to the measured value of the torque is compared. Evaluation means for evaluating fluidity as plastic fluidity of the excavated soil at the time of construction. An apparatus for evaluating plastic fluidity of excavated soil in a chamber in an earth pressure shield method.   The said evaluation means evaluates at least one of a slump value and a slump flow value as the plastic fluidity of the said excavated soil, The plastic fluidity evaluation of the excavated soil in a chamber in the earth pressure type shield method according to claim 3 characterized by the above-mentioned. apparatus. The excavated soil in the chamber is agitated by the agitating blade installed on the cutter spoke side and the agitator which is driven to rotate independently of the cutter spoke to impart plastic fluidity to the excavated soil, and the earth pressure of the excavated soil is increased. An earth pressure shield excavator that excavates while stabilizing the face by acting on the face,
An earth pressure shield excavator, comprising: an apparatus for evaluating the plastic flowability of excavated soil in a chamber in the earth pressure shield method according to claim 3.

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