System and method for determining flow value of plastic grout material

Abstract

To provide a system and method capable of determining the flow value of a plastic grout being injected with a degree of accuracy suitable for practical use when the plastic grout is injected.SOLUTION: A system of the present invention (100) has a shear rate-shear stress characteristics and yield stress determination block for multiple types of plastic grout materials with different flow values (10A), a yield stress-flow value function determination block (10B) for determining flow values of the plurality of types of grout materials as a function or characteristic of yield stress, a shear rate calculation block (10C) for the plastic grout material and the plurality of types of grout materials for which flow value (F) is to be determined, a shear stress calculation block (10D), a yield stress determination block (10E) of the grout material for which the flow value is to be determined, and a flow value determination block (10F) that determines the flow value of the grout material whose flow value is to be determined using the yield stress and the function or characteristic.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a plastic grout material, which is an injection material for filling voids, joints, cracks in the ground or a structure, or gaps that occur between the ground and a structure, and to a technique for determining the flow value of the plastic grout material. [Background technology]

[0002] The term "plasticity" refers to the property of becoming fluid when shear force is applied, but not when shear force is not applied. Such plastic grout is very useful, for example, for injection into the back cavity of a tunnel, as shown in the cross section of Figure 17. When pumping plastic grout, if shear force is applied with a pump or other device just before pumping to increase fluidity, it can be easily pumped to the intended filling location. After filling the designated location, the fluidity decreases because no shear force is applied, and the grout remains in the filled area and hardens. In Figure 17, the tunnel cross section has linings consisting of partially arc-shaped left and right sidewall concrete 1 on the left and right sidewalls of the tunnel, and arch concrete 2 bridging the left and right sidewall concrete 1. There are cases where a cavity 3 is formed behind this lining (the natural ground side: the upper side in Figure 17) for some reason. If such a cavity is present, stress from the natural ground will not be transmitted evenly, which could cause harmful deformation in the tunnel body. To prevent the formation of cavity 3 behind arch concrete 2 (the natural ground side: the upper side in Figure 17) and a decrease in the strength of the tunnel body, "back cavity injection work" is carried out, in which grout material is filled into cavity 3 behind arch concrete 2 to fill cavity 3. In this construction work, injection port H2 is excavated in the ceiling of the tunnel inner wall (the upper region in Figure 17) from a position 0.1 m away from the center line Lc of the tunnel toward the natural ground, and injection ports H1 and H3 are excavated on both sides of the center line Lc from positions 2.5 m away toward the natural ground. Plastic grout material is then injected into injection ports H1 to H3. In Figure 17, the injected state of the grout material is shown as regions R1 to R3.

[0003] Plastic grout is often used to fill gaps and cavities that cannot be seen directly, such as the back of tunnel coverings, underground cavities, gaps between rubble stones, etc. The size of the gaps and cavities into which plastic grout is injected varies depending on the construction site, and effective filling can be achieved by injecting plastic grout that has a flow value (fluidity) appropriate for the size of the gap or cavity. However, injection of plastic grout material is generally carried out using a single mix, and after injection has begun, switching to a mix with a different flow value depending on conditions such as injection pressure is not performed. Even if the flow value is changed to a different formulation during injection of the plastic grout material, in the prior art, the flow value after the formulation change had to be determined by sampling the plastic grout material being injected and conducting a flow test, which required a great deal of effort to determine the flow value after the change.

[0004] Another prior art proposed is a technique for continuously measuring the slump value of fresh concrete (see Patent Document 1). In this prior art (Patent Document 1), the slump value is calculated as a linear function of the pressure loss in the flow of fresh concrete. However, since plastic grout materials are evaluated by flow value (change in spread) rather than slump value (change in height), they cannot be calculated as a simple linear function, and it is impossible to apply the related art (Patent Document 1) to determine the flow value of plastic grout materials from pressure loss with a level of accuracy suitable for practical use. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-21828 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been proposed in consideration of the above-mentioned problems of the prior art, and aims to provide a system and method that can determine the flow value of a plastic grout material being injected with a level of accuracy suitable for practical use when the plastic grout material is being injected. The flow value in the present invention is, for example, a cylindrical, bottomless container (flow cone) filled with grout, and when the flow cone is pulled up, the spread of the grout packed in the flow cone is measured in two directions, and the average of the measured values ​​is calculated. There are no particular restrictions on the size or shape of the flow cone. [Means for solving the problem]

[0007] As a result of various research and experiments, the inventors have noticed that the flow value (F) of plastic grout material is proportional to the "-1 / 2 power" of the yield stress (τy). Here, the yield stress (τy) of plastic grout material is the value below which shear stress (τ) does not cause flow, but above which shear stress (τ) the plastic grout material flows steadily at a constant shear rate (γ).

[0008] Based on this finding, the system (100) for determining the flow value (F) of a plastic grout material of the present invention comprises a shear rate-shear stress characteristic and yield stress determination block (10A) having the function of determining the shear rate-shear stress characteristic (γ-τ characteristic) and yield stress (τy) of multiple types (for example, three types) of plastic grout materials with different flow values ​​(F); The flow values ​​(F) of the various types of plastic grout materials are calculated as a function of the reciprocal of the square root of the determined yield stress (τy) (F=a / (τy) 1 / 2 : a is a constant that varies depending on the plastic grout material) or characteristic (characteristics of yield stress and flow value), a yield stress-flow value function determination block (10B); A shear rate calculation block (10C) having a function of calculating the shear rate (γ) of the plastic grout material from the flow rate (Q) of the plastic grout material whose flow value (F) is to be determined and multiple types (for example, three types) of plastic grout materials having different flow values ​​(F); A shear stress calculation block (10D) having a function of calculating the shear stress (τ) of the plastic grout material from the pressure loss (ΔP) of the plastic grout material whose flow value (F) is to be determined and multiple types (e.g., three types) of plastic grout materials having different flow values ​​(F); A yield stress determination block (10E) having a function of determining the yield stress (τR) of a plastic grout material for which a flow value (F) is to be determined using the shear rate-shear stress characteristics (γ-τ characteristics) determined by the shear rate-shear stress characteristics and yield stress determination block (10A); The yield stress (τR) determined in the yield stress determination block (10E) and the function (e.g., F=a / (τy)) determined in the yield stress-flow value function determination block (10B) are used. 1 / 2 ) or characteristics, and has a flow value determination block (10F) that has the function of determining the flow value (FR) of the plastic grout material whose flow value (FR) is to be determined.

[0009] Furthermore, the method of determining the flow value (F) of the plastic grout material of the present invention based on the above-mentioned findings is as follows: A shear rate-shear stress characteristic determination step of determining the shear rate-shear stress characteristics (γ-τ characteristics) of multiple types (e.g., three types) of plastic grout materials having different flow values ​​(F); The yield stress (τy) of the plurality of types of plastic grout materials is determined, and the flow value (F) of the plurality of types of plastic grout materials is calculated as a function of the reciprocal of the square root of the determined yield stress (τy) (F=a / (τy) 1 / 2 a is a constant that varies depending on the plastic grout material) or characteristic (characteristics of yield stress and flow value); a shear rate and shear stress calculation step of calculating the shear rate (γ) and shear stress (τ) of the plastic grout material from the flow rate (Q) and pressure loss (ΔP) of the plastic grout material whose flow value is to be determined; a yield stress determination step of determining the yield stress (τR) of the plastic grout material whose flow value is to be determined using the shear rate-shear stress characteristics (γ-τ characteristics) determined in the shear rate-shear stress characteristic determination step; The yield stress (τR) determined in the yield stress determination step and the function (F=a / (τy)) determined in the yield stress-flow value function determination block 1 / 2 ) or characteristics of the plastic grout material, the flow value (FR) of which is to be determined is determined.

[0010] The construction system (101) for carrying out the injection method of the present invention is as follows: A system (101) for injecting a two-component mixed type plastic grout material, the plastic grout material containing two kinds of materials (e.g., liquid A as a base material and liquid B as a plastic material), in which the flow value (F) increases when there is a large amount of one material (e.g., liquid A), and the flow value (F) decreases when there is a large amount of the other material (e.g., liquid B), The system includes a base material supply system (40) and a plasticizer supply system (50), each of which is provided with a material pump (42, 52, e.g., a grout pump) and a flow meter (43, 53). A mixing device (61: for example, a static mixer installed at the confluence) and pressure sensors (62A, 62B) are installed at the confluence of the base material supply system (40) and the plasticizer supply system (50) or downstream thereof, and the pressure sensors (62A, 62B) are arranged at two different positions; The control device (11) includes: A function of calculating the flow rate (Q) and flow velocity (V) of the plastic grout material from the measurement results of the flow meter (43) installed in the base material supply system (40) and the flow meter (53) installed in the plastic material supply system (50); A function to calculate pressure loss (ΔP) from the measurement results of pressure sensors (62A, 62B) at two different locations, A function to determine the shear rate-shear stress characteristics (γ-τ characteristics) of multiple types (e.g., three types) of plastic grout materials with different flow values, The yield stress (τy) of the plurality of types of plastic grout materials is determined, and the flow value (F) of the plurality of types of plastic grout materials is calculated as a function of the reciprocal of the square root of the determined yield stress (τy) (F=a / (τy) 1 / 2 : a is a constant that varies depending on the plastic grout material) or a function that determines the characteristics (yield stress and flow value characteristics), A function to calculate the shear rate (γ) and shear stress (τ) of the plastic grout material from the flow rate (Q) and pressure loss (ΔP) of the plastic grout material whose flow value is to be determined; A function of determining the yield stress (τR) of a plastic grout material whose flow value is to be determined using the determined shear rate-shear stress characteristic (γ-τ characteristic); The determined yield stress (τR) and the determined function (F=a / (τy) 1 / 2 ) or characteristics to determine the flow value (FR) of the plastic grout material whose flow value is to be determined; The determined flow value (FR) is compared with a range of flow values ​​that is suitable for the application conditions, and if the determined flow value (FR) is smaller than the range of flow values, the flow rate of the base material (liquid A) is increased; if the determined flow value (FR) is larger than the range of flow values, the flow rate of the plasticizer (liquid B) is increased; and if the determined flow value (FR) is within the range of flow values, the flow rate of the base material (liquid A) and the flow rate of the plasticizer (liquid B) are maintained.

[0011] The injection method of the present invention includes: This is an injection method for injecting a two-component mixed type plastic grout material, which contains a base material (liquid A) and a plasticizer (liquid B). The flow value (F) increases when there is a large amount of base material (liquid A), and decreases when there is a large amount of plasticizer (liquid B). The system includes a base material supply system (40) and a plasticizer supply system (50), each of which is provided with a material pump (42, 52, e.g., a grout pump) and a flow meter (43, 53). At the confluence of the base material supply system (40) and the plasticizer supply system (50) or downstream thereof, a mixing device (61, e.g., a static mixer installed at the confluence) and pressure sensors (62A, 62B) are installed, and the pressure sensors (62A, 62B) are located at two different positions. Before injection, the shear rate-shear stress characteristics (γ-τ characteristics) of multiple types (e.g., three types) of plastic grout materials with different flow values ​​are determined, the yield stress (τy) of the multiple types of plastic grout materials is determined, and the flow value (F) of the multiple types of plastic grout materials is calculated as a function of the reciprocal of the square root of the determined yield stress (τy) (F=a / (τy) 1 / 2 ) a is a constant that varies depending on the plastic grout material) or characteristic (yield stress and flow value characteristic); a step of calculating the flow rate (Q) and flow velocity (V) of the plastic grout material from the measurement results of the flow meter (43) installed in the base material supply system (40) and the flow meter (53) installed in the plastic material supply system (50) when injecting the plastic grout material; A step of calculating a pressure loss (ΔP) from measurement results of pressure sensors (62A, 62B) at two different positions; A step of calculating the shear rate (γ) and shear stress (τ) of the plastic grout material from the flow rate (Q) and pressure drop (ΔP) of the plastic grout material whose flow value is to be determined; A step of determining the yield stress (τR) of the plastic grout material whose flow value is to be determined using the determined shear rate-shear stress characteristic (γ-τ characteristic); The determined yield stress (τR) and the determined function (F=a / (τy) 1 / 2 ) or characteristics to determine the flow value (FR) of the plastic grout material for which the flow value is to be determined; The method is characterized by comprising a step of comparing the determined flow value (FR) with a range of flow values ​​that is suitable for the application conditions, increasing the flow rate of the base material (liquid A) if the determined flow value (FR) is smaller than the range of flow values, increasing the flow rate of the plasticizer (liquid B) if the determined flow value (FR) is larger than the range of flow values, and maintaining the flow rates of the base material (liquid A) and the plasticizer (liquid B) if the determined flow value (FR) is within the range of flow values. [Effects of the Invention]

[0012] According to the present invention having the above-mentioned configuration, the shear rate-shear stress characteristics (γ-τ characteristics) of multiple types (e.g., three types) of plastic grout materials having different flow values ​​are determined, The yield stress (τy) of the plurality of types of plastic grout materials is determined, and the flow value (F) of the plurality of types of plastic grout materials is calculated as a function of the reciprocal of the square root of the determined yield stress (τy) (F=a / (τy) 1 / 2 ) or determine the characteristics, When injecting the plastic grout material, the flow rate (Q) and flow velocity (V) of the plastic grout material are calculated from the measurement results of the flow meter (43) installed in the base material supply system (40) and the flow meter (53) installed in the plastic material supply system (50); The pressure loss (ΔP) is calculated from the measurement results of pressure sensors (62A, 62B) at two different locations. Calculating the shear rate (γ) and shear stress (τ) of the plastic grout material from the flow rate (Q) and pressure loss (ΔP) of the plastic grout material whose flow value is to be determined; Determine the yield stress (τR) of the plastic grout material whose flow value is to be determined using the determined shear rate-shear stress characteristic (γ-τ characteristic); The determined yield stress (τR) and the determined function (F=a / (τy) 1 / 2 ) or characteristics are used to determine the flow value (FR) of the plastic grout material whose flow value is to be determined, When applying plastic grout used in injection methods, the flow value of the plastic grout being injected can be determined with a high degree of accuracy suitable for practical use. For example, while carrying out the injection method, the flow value of the grout being injected can be determined with a high degree of accuracy suitable for practical use. The determined flow value (FR) is compared with a range of flow values ​​that is suitable for the application conditions, and if the determined flow value (FR) is smaller than the range of flow values, the flow rate of the base material (liquid A) is increased, if the determined flow value (FR) is larger than the range of flow values, the flow rate of the plasticizer (liquid B) is increased, and if the determined flow value (FR) is within the range of flow values, the flow rates of the base material (liquid A) and the plasticizer (liquid B) can be maintained, The flow value of the injected plastic grout material can be adjusted within a range of flow values ​​that suits the construction conditions. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is an explanatory diagram showing the balance of forces in grout material flowing inside a circular pipe. [Figure 2] FIG. 1 is a characteristic diagram illustrating the γ-τ characteristics of various fluids. [Figure 3] FIG. 1 is a characteristic diagram illustrating the γ-τ characteristics of a Bingham fluid. [Figure 4] FIG. 1 is an explanatory diagram showing a flow velocity distribution in a Newtonian fluid. [Figure 5] FIG. 1 is an explanatory diagram showing the flow velocity distribution in a Bingham fluid. [Figure 6] This is a γ-τ characteristic diagram similar to Figure 3, calculated from three types of flow velocities and the pressure loss at each for grout material with known flow values. [Figure 7] This is a characteristic diagram showing the γ-τ characteristics of three types of grout materials with different flow values. [Figure 8] FIG. 8 is a characteristic diagram showing the yield stress τy-flow value F characteristic created using the yield stresses obtained from the three types of characteristics shown in FIG. [Figure 9] FIG. 8 is an explanatory diagram illustrating a mode of determining the yield stress τR from the measured values ​​of the flow velocity and pressure loss of the grout material from the characteristic diagram of FIG. [Figure 10]FIG. 10 is an explanatory diagram illustrating a mode of determining the flow value FR of the grout material by measuring the flow velocity and pressure loss from the yield stress τR determined from FIG. 9. [Figure 11] 1 is a functional block diagram of a system for determining a flow value of a plastic grout material according to a first embodiment of the present invention. [Figure 12] 1 is a flowchart showing an overview of a method for determining a flow value of a plastic grout material according to a first embodiment of the present invention. [Figure 13] 13 is a flowchart showing the details of step SA in FIG. 12. [Figure 14] 13 is a flowchart showing the details of step SB in FIG. 12. [Figure 15] FIG. 10 is a block diagram showing a system for carrying out injection work according to a second embodiment of the present invention. [Figure 16] 10 is a flowchart showing the procedure for adjusting the flow value in the injection work according to the second embodiment of the present invention. [Figure 17] This is a cross-sectional view of a tunnel where backfilling work is being carried out. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, the mechanism for determining the flow value of a plastic grout material will be described with reference to Figures 1 to 10. Here, the characteristics of the plastic grout material will be mainly described with reference to Figures 1 to 5. Then, the manner in which the γ-τ characteristics, yield stress τy, and flow value F of the plastic grout material are determined will be described with reference to Figures 6 to 10. In Figure 1, the balance of forces in a specified section (length L) of grout flowing in the direction of arrow F inside a circular pipe of diameter D can be expressed by the following formula. P1·(πD 2 / 4)=P2·(πD 2 / 4)+τ·πDL Here, P1 and P2 are the pressures at the downstream and upstream ends of a given section (length L), and τ is the shear stress. The pressure loss (pressure fluctuation) ΔP is ΔP = P1 - P2, so the above equation becomes: ΔP·(πD 2 / 4)=τ·πDL From this equation, the following equation (1) can be obtained. τ=(ΔPD / 4L) (1)

[0015] The pressure loss ΔP of a fluid flowing inside a circular pipe can be expressed by the following formula (Darcy-Weisbach formula). ΔP=F·(L / D)·(ρV 2 / 2) Here, ρ is the density of the fluid and F is the friction loss coefficient. Assuming that the flow is laminar, the friction loss coefficient F can be expressed as F=64 / Re using the Reynolds number Re, so the above equation can be transformed as follows: ΔP=(64 / Re)·(L / D)·(ρV 2 / 2) The Reynolds number Re can be expressed as Re = (DVρ / μ) using the flow velocity V, so by substituting the Reynolds number Re and apparent viscosity μ = (τ / γ) into the above equation, the above equation can be expressed as follows: ΔP=(32LV / D 2 )·(τ / γ) By substituting equation (1) into this equation, the following equation (2) can be obtained, which represents the shear rate γ. γ=(8V / D) (2)

[0016] Figure 2 shows the shear rate γ and shear stress τ characteristics for various fluids. When calculating the above equations (1) and (2), the Reynolds number Re and apparent viscosity μ for Newtonian fluids are used, but plastic grout materials are considered to be Bingham fluids and are actually different from Newtonian fluids. Figure 2 also shows the γ-τ characteristics for pseudoplastic fluids and dilatant fluids in addition to the γ-τ characteristics for Bingham fluids and Newtonian fluids. Figure 4 shows the flow velocity distribution of a Newtonian fluid in a circular pipe, and Figure 5 shows the flow velocity distribution of a Bingham fluid in a circular pipe. In Figures 4 and 5, the direction of flow is indicated by arrow F. While the flow velocity distribution of the Newtonian fluid in Figure 4 is parabolic flow, the flow velocity distribution of the Bingham fluid in Figure 5 occurs in the circular pipe as a plug flow. Although a detailed explanation is omitted, in order to accurately determine the value of shear rate for a Bingham fluid from the flow velocity, pressure loss, etc. in a circular pipe, complex calculations including repeated calculations are required. In the illustrated embodiment, the purpose is to determine the flow value of the plastic grout material from the pressure drop and flow velocity values, not to determine the true value of the yield stress τy of the plastic grout material. Furthermore, even if the shear stress τ and shear rate γ are calculated using the Reynolds number Re and apparent viscosity μ of a Newtonian fluid, there is no difference in the flow value calculated by the method of the embodiment. Therefore, in the illustrated embodiment, as a simple calculation method, the shear stress and shear rate of the plastic grout material, which is a Bingham fluid, are calculated using the Reynolds number Re and apparent viscosity μ of a Newtonian fluid.

[0017] In Figure 3, which shows the γ-τ characteristic of plastic grout, a Bingham fluid, the increase in shear stress τ due to an increase in unit shear rate γ is the plastic viscosity ηB. Also, the shear stress τ when the shear rate γ is 0 (zero) is the yield stress τy. The yield stress τy of a plastic grout material is a value below which the plastic grout material does not flow at shear stress τ, but above which the plastic grout material flows steadily at a constant shear rate γ.

[0018] Next, a procedure for determining the flow value of a plastic grout material whose flow value is to be determined will be described with reference to FIGS. For multiple types (e.g., three types) of plastic grout materials whose flow values ​​F are to be determined and which have different flow values ​​from each other, the shear rate-shear stress characteristics (γ-τ characteristics) are determined (Figures 6 and 7), and the yield stress τy for each of the multiple types (e.g., three types) of plastic grout materials is determined (Figure 7). Next, the flow value F of the multiple types (e.g., three types) of plastic grout materials is calculated as a function of the reciprocal of the square root of the determined yield stress τy (F=a / (τy) 1 / 2 ) (a is a constant) or characteristic (Figure 8). The function (F=a / (τy) 1 / 2 ) or characteristics will be described later. Then, the shear rate and shear stress of the plastic grout material are calculated from the flow rate (flow velocity) and pressure loss of the plastic grout material for which the flow value is to be determined, and the yield stress τR of the plastic grout material for which the flow value is to be determined is determined using the shear rate-shear stress characteristics (γ-τ characteristics: Figure 7) (Figure 9). Then, the function of the yield stress τR and the flow value (F=a / (τy) 1 / 2 ) or characteristics, the flow value FR of the plastic grout material whose flow value is to be determined is determined from the determined yield stress τR (Figure 10). This will be explained in detail below with reference to FIGS.

[0019] When determining the shear rate-shear stress characteristic diagram (γ-τ characteristic diagram) of plastic grout material as shown in Figure 6, the diameter D of the pressure pipe and the length L of the section over which pressure loss is measured are determined (for example, D = 40 mm, L = 2 m: see Figure 1), and the flow velocity V is changed (V1, V2, V3: i.e., the flow rate Q is changed) to calculate the pressure loss ΔP (ΔP1, ΔP2, ΔP3) for each case. As explained with reference to Figure 1, the shear stress τ and shear rate γ can be expressed by the above-mentioned formulas (1) and (2), so the shear rate γ can be calculated from the flow velocity V (V1, V2, V3) using formula (2). Then, the shear stress τ can be calculated from the pressure loss ΔP (ΔP1, ΔP2, ΔP3) using formula (1). In Figure 6, the shear rate-shear stress characteristic curve (γ-τ characteristic curve) of the plastic grout material at a certain flow value F (for example, F = 100 mm) can be determined from the three plots (γ1, τ1), (γ2, τ2), and (γ3, τ3) obtained by changing the flow velocity V to V1, V2, and V3. From this γ-τ characteristic curve, the characteristics of the plastic grout material can be determined. The yield stress τy, which is the τ axis intercept, can be calculated from τ=τy+ηB (ηB is the plastic viscosity).

[0020] In Figure 7, the shear rate-shear stress characteristics (γ-τ characteristics) of several types of plastic grout materials, for example, flow values ​​F = 100 mm, F = 120 mm, and F = 140 mm, are determined, and the shear rate-shear stress characteristics (γ-τ characteristics) of the three types of plastic grout materials are displayed together. From the γ-τ characteristics of three types of plastic grout materials with flow values ​​F = 100mm, 120mm, and 140mm, the yield stresses τ100, τ120, and τ140 of the three types of plastic grout materials can be calculated. Here, the yield stresses of the three types of plastic grout materials are sometimes collectively referred to as "τy."

[0021] Figure 8 shows the relationship between the flow value F and the yield stress τy of three types of plastic grout materials. The flow value F is a function of the reciprocal of the square root of the yield stress τy (F=a / (τy) 1 / 2 ) or characteristic, where "a" is a constant that varies for each plastic grout material. In Figure 8, the vertical axis represents the flow value F of the plastic grout material, and the horizontal axis represents the yield stress τy of the plastic grout material. Three plots are displayed in Figure 8 using the flow values ​​F = 100mm, F = 120mm, and F = 140mm of the three types of plastic grout material mentioned above, and their respective yield stresses τ100, τ120, and τ140, and the yield stress τy - flow value F characteristic curve (F = a / (τy) 1 / 2 ) has been decided. Here, the yield stress τy-flow value F characteristic curve is F=a / (τy) 1 / 2) or its characteristics can be found by calculation using commercially available software (for example, Microsoft's "Excel") from the three plots in Figure 8. Alternatively, when estimating the yield stress τy from the flow value F, since the yield stress τy is inversely proportional to the square of the flow value F, the relationship between the flow value F and the yield stress τy can be found by the least squares method, assuming that the flow value F is inversely proportional to the square root of the yield stress τy. And the flow value F=a / (τy) 1 / 2 The constant a is determined as follows.

[0022] Figure 7 shows the shear rate-shear stress characteristic diagram (γ-τ characteristic diagram) for three types of plastic grout materials with flow values ​​F = 100 mm, 120 mm, and 140 mm, and Figure 8 shows the yield stress τy-flow value F characteristic curve (F = a / (τy) 1 / 2 ) is used to determine the yield stress τR of the plastic grout material whose flow value is to be determined (Fig. 9), and the flow value FR is determined (Fig. 10). The details will be explained below with reference to Figs. 9 and 10. In Figure 9, the section length L and the pressure pipe diameter D are the data explained with reference to Figure 1. For example, when performing injection construction, the flow velocity V and pressure loss ΔP of the plastic grout material for which the flow value FR is to be determined are measured, and the shear rate and shear stress are calculated using the above-mentioned equations (1) and (2). In the example of Figure 9, the plot (γ0, τ0) of the shear rate γ0 and shear stress τ0 of the plastic grout material (for which the flow value is to be determined) obtained using the above equations (1) and (2) is located in the region between the γ-τ characteristic line of the plastic grout material with a flow value F = 120 mm and the γ-τ characteristic line with a flow value F = 140 mm. The γ-τ characteristic line R of the plastic grout material for which the flow value FR is to be determined can be determined by proportionally allocating the distance along the τ axis (vertical axis) between the γ-τ characteristic line of the plastic grout material with a flow value F = 120 mm and the γ-τ characteristic line of the plastic grout material with a flow value F = 140 mm. Once the γ-τ characteristic line R of the plastic grout material for which the flow value FR is to be determined is found, the yield stress τR, which is the τ-axis intercept of the characteristic line R, can be found.

[0023] Here, it is preferable to determine the flow values ​​of the three types of plastic grout materials so that characteristic line R in Figure 9 (the γ-τ characteristic line of the plastic grout material for which the flow value FR is to be determined) is in the region between the three γ-τ characteristic lines in Figure 7. If the characteristic line R in Figure 9 is outside the region between the three γ-τ characteristic lines in Figure 7 (if it is in a region above or below the three γ-τ characteristic lines in Figure 7), the yield stress τR is determined by assuming that the characteristic line R extends parallel to the nearest γ-τ characteristic line (the γ-τ characteristic line among the three γ-τ characteristic lines in Figure 7 that is closest to the characteristic line R).

[0024] In Figure 10, the flow value FR (for example, the flow value of the plastic grout during injection construction) can be calculated from the yield stress τR (of the plastic grout for which the flow value FR is to be determined) determined in Figure 9. In this case, a characteristic diagram showing the relationship between the flow value F of the plastic grout and the yield stress τy, as shown in Figure 8, is used. Alternatively, the flow value FR of the plastic grout material to be determined is a function that shows the relationship between the flow value F of the plastic grout material and the yield stress τy (F=a / (τy) 1 / 2 ) or can be calculated from the characteristics.

[0025] Next, a first embodiment of the present invention will be described with reference to FIGS. The first embodiment, shown in Figures 11 to 14, relates to a system and method for determining the flow value of a plastic grout material. In FIG. 11, the system for determining the flow value of a plastic grout material according to the first embodiment is generally indicated by the reference numeral 100, and includes a control device 10, an input device 20, and a display device 30 (display). The control device 10 has a shear rate-shear stress characteristic and yield stress determination block 10A, a yield stress-flow value function determination block 10B, a shear rate calculation block 10C, a shear stress calculation block 10D, a yield stress determination block 10E, a flow value determination block 10F, a flow velocity determination block 10G, and a database 10H (memory device).

[0026] The input device 20 receives data related to the pressure pipe shown in FIG. 1 (pipe diameter D, section length L, FIG. 1) and measurement values ​​(calculated values) of the flow rate Q and pressure loss ΔP obtained from measuring devices (flow meter, pressure meter) not shown, and outputs the data and measurement values ​​to the control device 10. The flow rate determination block 10G receives the measured value of the flow rate Q from the input device 20 via a signal transmission line SL1, and calculates the flow rate V from the measured value of the flow rate Q and the pipe diameter D. The flow rate V calculated by the flow rate determination block 10G is sent to the shear rate calculation block 10C via a signal transmission line SL2, and is also sent to the shear stress calculation block 10D via a signal transmission line SL3.

[0027] The shear rate calculation block 10C receives data on the pressure pipe (pipe diameter D, section length L: Figure 1) from the input device 20 via signal transmission lines SL1 and SL2, receives the flow rate V from the flow rate determination block 10G, and calculates the shear rate γ of the plastic grout material using the above formula (2). In addition, the shear rate calculation block 10C receives data regarding the pressure pipe (pipe diameter D, section length L) and the flow velocities V of three types of plastic grout materials with known but different flow values ​​from the input device 20 via signal transmission lines SL1 and SL2, and has the function of calculating the shear rate γ of each of the three types of plastic grout materials with different flow values. The shear rate γ of the plastic grout material (for which the flow value is to be determined) calculated in the shear rate calculation block 10C is sent to the yield stress determination block 10E via a signal transmission line SL4. Also, the shear rates γ of the three types of plastic grout material for which the flow value F calculated in the shear rate calculation block 10C is known are sent to the shear rate-shear stress characteristics and yield stress determination block 10A via a signal transmission line SL5.

[0028] The shear stress calculation block 10D receives data on the pressure pipe (pipe diameter D, section length L) and the pressure loss ΔP of the plastic grout material (for which the flow value is to be determined) from the input device 20 via signal transmission lines SL1 and SL3, and has the function of calculating the shear stress τ of the plastic grout material (for which the flow value is to be determined) using the above equation (1). In addition, the shear stress calculation block 10D receives data regarding the pressure pipe (pipe diameter D, section length L) from the input device 20 via signal transmission lines SL1 and SL3, and receives the pressure loss ΔP of multiple (three) types of plastic grout materials with different known flow values, and has the function of calculating the shear stress τ of each of the three types of plastic grout materials with known flow values ​​using the above formula (1). The shear stress τ of the plastic grout material (for which the flow value is to be determined) calculated in the shear stress calculation block 10D is transmitted to the yield stress determination block 10E via signal transmission line SL6, and the shear stress τ of three types of plastic grout material for which the flow value F is known calculated in the shear rate stress block 10D is transmitted to the shear rate-shear stress characteristic and yield stress determination block 10A via signal transmission line SL7.

[0029] In Figure 11, the shear rate-shear stress characteristics and yield stress determination block 10A obtains the shear rate γ of three different types of plastic grout materials with known flow values ​​F from the shear rate calculation block 10C, and obtains the shear stress τ of the three types of plastic grout materials with known flow values ​​from the shear stress calculation block 10D. The shear rate-shear stress characteristic and yield stress determination block 10A has the function of determining the γ-τ characteristics (each of the three characteristics) of multiple types (three types) of plastic grout materials with different flow values ​​F based on the acquired shear rate γ and shear stress τ. The determination of the γ-τ characteristics by the shear rate-shear stress characteristics and yield stress determination block 10A is carried out in the manner described with reference to FIGS. The shear rate-shear stress characteristic and yield stress determination block 10A has the function of determining the yield stress τy for each of the three types of plastic grout materials with known flow values ​​based on the determined γ-τ characteristics. The determined yield stress τy corresponds to τ100, τ120, and τ140 in Figure 7, and is determined in the manner described with reference to Figure 7. The γ-τ characteristics and yield stress τy determined in the shear rate-shear stress characteristics and yield stress determination block 10A are transmitted to the yield stress-flow value function determination block 10B via signal transmission line SL8 and also to the database 10H via signal transmission line SL9.

[0030] The yield stress-flow value function determination block 10B determines the flow values ​​F of the three types of grout materials as a function of the reciprocal of the square root of the determined yield stress τy (F=a / (τy)) based on the γ-τ characteristics and yield stress τy (τy=τ100, τ120, τ140) of each of the three types of plastic grout materials whose flow values ​​are known and obtained from the shear rate-shear stress characteristics and yield stress determination block 10A. 1 / 2 ) or determines a characteristic corresponding to the function. It should be noted that the yield stress-flow value function determination block 10B can have a function for determining not only the function but also the characteristic. The function determined in the yield stress-flow value function determination block 10B (F=a / (τy) 1 / 2 ) or the characteristics are transmitted to the database 10H via a signal transmission line SL10.

[0031] The yield stress determination block 10E acquires the shear rate γ from the shear rate calculation block 10C, acquires the shear stress τ from the shear stress calculation block 10D, and further acquires the γ-τ characteristics of plastic grout materials with three known flow values ​​from the database 10H via the signal transmission line SL11. Here, the yield stress determination block 10E acquires the shear rate γ and shear stress τ of the plastic grout material for which the flow value FR is to be determined. The yield stress determination block 10E has a function of determining the yield stress τR of the plastic grout material for which the flow value FR is to be determined based on the acquired γ-τ characteristics. The determination of the yield stress τR is performed in the manner described in FIG. The yield stress τR determined in the yield stress determination block 10E (the yield stress τR of the plastic grout material for which the flow value FR is to be determined) is sent to the flow value determination block 10F via a signal transmission line SL12.

[0032] The flow value determination block 10F acquires the yield stress τR from the yield stress determination block 10E, and acquires the function or characteristic of the flow value F of the plastic grout material from the database 10H via the signal transmission line SL13, and determines the flow value FR of the plastic grout material for which the flow value FR is to be determined based on the acquired yield stress τR and the function or characteristic of the flow value of the plastic grout material. The determination of the flow value FR by the flow value determination block 10F is performed in the manner described in Figure 10. The flow value FR determined by the flow value determination block 10F is transmitted to the display device 30 (display) via a signal transmission line SL14. The display device 30 (display) displays the determined flow value FR and, if necessary, transmits it to the input device 20 via a signal transmission line SL15 to store it in the management means of the construction manager.

[0033] The database 10H has the function of acquiring and storing the γ-τ characteristics and yield stress τy for three types of plastic grout materials whose flow values ​​F are known and determined in the shear rate-shear stress characteristics and yield stress determination block 10A, as well as acquiring and storing the function or characteristics of the yield stress τy and flow value F of the plastic grout material determined in the yield stress-flow value function determination block 10B. The γ-τ characteristics of the three types of plastic grout materials stored in the database 10H are used by the yield stress determination block 10E when determining the yield stress τR of the plastic grout material whose flow value is to be determined. In addition, the function or characteristic of the yield stress τR and flow value F of the plastic grout material stored in the database 10H is used by the flow value determination block 10F when determining the flow value FR of the plastic grout material for which the flow value F is to be determined.

[0034] FIG. 12 shows an outline of the procedure for determining the flow value of a plastic grout material in the system 100 according to the first embodiment, and FIGS. 13 and 14 show steps SA and SB in FIG. 12 in more detail. In FIG. 12, in step SA, the γ-τ characteristics and yield stress τy of each of three types of plastic grout materials with different known flow values ​​are determined (shear rate-shear stress characteristic determination step, yield stress determination step). Furthermore, in step SA, the flow values ​​F of the three types of plastic grout materials are calculated as a function of the reciprocal of the square root of the determined yield stress τy (F=a / (τy) 1 / 2 ) or as a characteristic corresponding to the function (characteristics of yield stress and flow value) (yield stress-flow value function determination step). Note that in step SA, a characteristic may be determined instead of a function. In step SB, the shear rate γ and shear stress τ of the plastic grout material for which the flow value FR is to be determined are determined from the flow rate Q and pressure loss ΔP of the plastic grout material (shear rate and shear stress calculation step), the yield stress τR of the plastic grout material for which the flow value is to be determined is determined using the shear rate-shear stress characteristic (γ-τ characteristic) (yield stress determination step), and further, the flow value FR of the plastic grout material for which the flow value is to be determined is determined using the yield stress τR and a function or characteristic of the flow value F, which is the reciprocal of the square root of the yield stress τy determined in step SA (flow value determination step).

[0035] In Fig. 13, which shows the details of step SA in Fig. 12, in step S11, three types of plastic grout materials, each with a known flow value and different from the others, are used in a predetermined section of a pressure pipe having a pipe diameter D and a section length L, and the flow rate Q or flow velocity V is changed to measure (calculate) the pressure loss ΔP. ​​Then, the process proceeds to step S12. In step S12, the shear stress τ (τ1, τ2, τ3) and shear rate γ (γ1, γ2, γ3) are calculated using the measured (calculated) values ​​of flow velocity V (V1, V2, V3) and pressure drop ΔP (ΔP1, ΔP2, ΔP3) in step S11 according to equations (1) and (2) described in Figure 1, and plotted on a shear rate-shear stress characteristic curve (γ-τ diagram). This plot is performed, for example, at three locations for each plastic grout material, and a γ-τ characteristic curve is determined by linear approximation (see Figures 6 and 7). A total of three γ-τ characteristic curves are determined for each of the three types of plastic grout materials, and a γ-τ characteristic diagram is then determined (see Figure 7). Furthermore, in step S12, the yield stress τy (τy = τ100, τ120, τ140) and plastic viscosity ηB (ηB = η100, η120, η140) are determined for each of the three types of plastic grout materials using the three characteristic lines of the three types of plastic grout materials (see Figure 7). Step S12 is executed by the shear rate calculation block 10C, the shear stress calculation block 10D, and the shear rate-shear stress characteristics and yield stress determination block 10A.

[0036] In the next step S13, based on the yield stress τy (τy = τ100, τ120, τ140) and flow value F (F = 100 mm, 120 mm, 140 mm) of the three types of plastic grout materials determined in step S12, a function (F = a / (τy)) that expresses the flow value F as the reciprocal of the square root of the yield stress τy is calculated by the least squares method. 1 / 2 ), or the characteristics of the yield stress τy and the flow value F corresponding to the function are determined (see FIG. 8). It should be noted that in step S13, the characteristics of the yield stress τy and the flow value F may be determined instead of the function. Step S13 is performed in the yield stress-flow value function determination block 10B.

[0037] 14, which shows the details of step SB in FIG. 12, in step S21, the pipe diameter D and section length L of the pressure conveying pipe are input, and the flow rate Q (flow velocity V) and pressure loss ΔP of the plastic grout material for which the flow value FR is to be determined are measured and calculated in the pressure conveying pipe, and then the process proceeds to step S22. In step S22, the shear rate γ and shear stress τ of the plastic grout material are calculated based on the pipe diameter D of the pressure pipe, the section length L, the flow rate Q (flow velocity V), and the pressure loss ΔP. Step S22 is performed in the shear rate calculation block 10C and the shear stress calculation block 10D, and the process then proceeds to step S23.

[0038] In step S23, the shear rate γ (γ0) and shear stress τ (τ0) calculated in step S22 are plotted on a diagram showing the γ-τ characteristics of the three types of plastic grout materials (flow values ​​F = 100 mm, 120 mm, 140 mm) determined in step S12 (Figure 13), thereby determining the characteristic line R and yield stress τR of the plastic grout material for which the flow value is to be determined (see Figure 9). Step S23 is performed in yield stress determination block 10E. In the next step S24, the yield stress τR determined in step S23 is converted into a function (F=a / (τy)) that expresses the flow value F determined in step S13 (FIG. 13) as the reciprocal of the square root of the yield stress τy. 1 / 2 ) or by plotting the characteristic corresponding to the function, the flow value FR of the plastic grout material for which the flow value FR is to be determined is determined (see FIG. 10). The control of step S24 is executed by the flow value determination block 10F.

[0039] Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment shown in Figures 15 and 16 applies the flow value determination technology of the first embodiment to injection construction, and relates to a system and method that can adjust the flow value in real time while injecting plastic grout material. In Fig. 15, the injection method construction system according to the second embodiment is generally indicated by the reference numeral 101. The injection method construction system 101 is a system for injecting a two-component mixed type plastic grout material. The plastic grout material is a type that contains a base material (liquid A) and a plasticizer (liquid B), and the flow value F increases when there is a large amount of base material (liquid A), and decreases when there is a large amount of plasticizer (liquid B). The injection method construction system 101 includes a base material supply system 40 and a plasticizer supply system 50. The base material supply system 40 is equipped with a mixing plant 41, a base material side grout pump 42 (a pump for pressure-feeding material), and a base material side flow meter 43. The plasticizer supply system 50 is equipped with a high-speed mixer 51, a plasticizer side grout pump 52 (a pump for pressure-feeding material), and a plasticizer side flow meter 53. At the confluence of the base material supply system 40 and the plasticizer supply system 50 or downstream thereof, a static mixer 61, which is a mixing device, and a pressure sensor 62 are installed, and the pressure sensor 62 includes a first pressure sensor 62A and a second pressure sensor 62B arranged at both ends of a steel pipe 63. The steel pipe 63 corresponds to the pressure transfer piping in FIG. 1, and the pressure sensors 62A and 62B are arranged with a section length L between them.

[0040] In FIG. 15, an injection method construction system 101 includes a control device 11 and an input device 20. The control device 11 has a flow rate / flow velocity and pressure loss calculation block 11A (Q, V, ΔP calculation block), a shear rate-shear stress characteristic and yield stress determination block 11B (γ-τ characteristic and τy determination block), a yield stress-flow value function determination block 11C (F=F(τy) determination block), a shear rate-shear stress calculation block 11D (γ, τ calculation block), a yield stress determination block 11E (τR determination block), a flow value determination block 11F, a judgment block 11G, a control signal generation block 11H, and a database 11I (storage device). As in the first embodiment, data (pipe diameter D, section length L) related to the pressure pipe (see Figure 1), and the flow rate Q, flow velocity V, and pressure loss ΔP of the plastic grout material obtained from measuring devices (flow meters 43, 53, pressure meters 62A, 62B) are input to the input device 20.

[0041] The flow rate / flow velocity and pressure loss calculation block 11A (Q, V, ΔP calculation block) acquires the flow rate in the base material supply system 40 from the base material-side flow meter 43 via a signal transmission line SL21, and acquires the flow rate in the plastic material supply system 50 from the plastic material-side flow meter 53 via a signal transmission line SL22. In addition, it acquires the pressure measured from the first pressure sensor 62A via a signal transmission line SL23, and acquires the pressure measured from the second pressure sensor 62B via a signal transmission line SL24. The Q, V, ΔP calculation block 11A calculates the flow rate Q (the combined value of the measurement values ​​of the base material side flow meter 43 and the plastic material side flow meter 53: flow rate) and flow velocity V of the plastic grout material from the measurement results of the base material side flow meter 43 and the plastic material side flow meter 53, and calculates the pressure loss ΔP from the measurement results of the first and second pressure sensors 62A and 62B. The flow rate Q, flow velocity V, and pressure loss ΔP calculated in the Q, V, ΔP calculation block 11A are transmitted to the shear rate / shear stress calculation block 11D (γ, τ calculation block) via a signal transmission line SL25.

[0042] The shear rate-shear stress characteristic and yield stress determination block 11B (γ-τ characteristic and τy determination block) calculates the shear rate γ and shear stress τ of the grout material using the flow rate Q, flow velocity V, pressure loss ΔP, and data on the pressure pipe (pipe diameter D, section length L) of three different types of plastic grout materials with known flow value F, using the above equations (1) and (2), determines the γ-τ characteristic for each grout material with different flow value (see Figures 6 and 7), and determines the yield stress τy of each of the three types of plastic grout materials (see Figure 7: τ100, τ120, τ140). The γ-τ characteristics and the yield stress τy determined in the γ-τ characteristics and τy determination block 11B are sent to the yield stress-flow value function determination block 11C (F=F(τy) determination block) via a signal transmission line SL27, and the γ-τ characteristics are then sent to the database 11I via a signal transmission line SL28.

[0043] The yield stress-flow value function determination block 11C (F = F(τy) determination block) determines the flow value FR as a function of the reciprocal of the square root of the yield stress τy (F = a / (τy)) based on the flow value and yield stress τy (τy = τ100, τ120, τ140) of each of the three types of plastic grout materials. 1 / 2 ) or as a characteristic of the yield stress τy and the flow value FR corresponding thereto. Note that Block 11C may determine a characteristic rather than a function. F=F(τy) The function F=a / (τy) determined in decision block 11C 1 / 2 Alternatively, the characteristics of the yield stress τy and the flow value FR are transmitted to the database 11I via the signal transmission line SL29.

[0044] The γ, τ calculation block 11D calculates and determines the shear rate γ and shear stress τ of the plastic grout material using the flow rate Q, flow velocity V, and pressure loss ΔP obtained from the Q, V, ΔP calculation block 11A using the above equations (1) and (2). Although not explicitly shown, the data of the pressure pipe (pipe diameter D, section length L) required to calculate the shear rate and shear stress may be stored in advance in the γ, τ calculation block 11D, or the data (pipe diameter D, section length L) stored in the database 11I may be used by the γ, τ calculation block 11D. The shear rate γ and shear stress τ calculated in the γ, τ calculation block 11D are transmitted to the yield stress determination block 11E (τR determination block) via a signal transmission line SL30.

[0045] The yield stress determination block 11E (τR determination block) has the function of determining the yield stress τR based on the shear rate γ and shear stress τ obtained from the γ, τ calculation block 11D and the γ-τ characteristics of each of three types of plastic grout materials with known flow values ​​obtained from the database 11I (see Figure 9). The yield stress τR determined in the τR determination block 11E is sent to the flow value determination block 11F via a signal transmission line SL32.

[0046] The flow value determination block 11F determines the yield stress τR obtained from the τR determination block 11E and the function of the yield stress and the flow value (F=a / (τy)) obtained from the database 11I via the signal transmission line SL33. 1 / 2 ) or based on the characteristics, the flow value FR of the plastic grout material whose flow value FR is to be determined is determined (see Figure 10). The flow value FR determined in the flow value determination block 11F is sent to the decision block 11G via a signal transmission line SL34. Although not clearly shown, the flow value FR determined by the flow value determination block 11F can be displayed on a display means not shown, or can be sent to the input device 20 and stored in the management means of the construction manager.

[0047] In Figure 15, the decision block 11G compares the flow value FR determined by the flow value determination block 11F with the range of flow values ​​that are suitable for the processing conditions, and if the determined flow value FR is smaller than the range of flow values, increases the flow rate of the base material (liquid A) (increases the flow rate of liquid A), if the determined flow value FR is larger than the range of flow values, increases the flow rate of the plasticizer (liquid B) (increases the flow rate of liquid B), and if the determined flow value FR is within the range of flow values, maintains the flow rate of the base material (liquid A) and the flow rate of the plasticizer (liquid B). Here, data regarding the "range of flow values ​​that are compatible with the application conditions for the plastic grout material" may be stored in advance in decision block 11G, or may be saved in database 11I and used in decision block 11G. The judgment result by the judgment block 11G (either "increase the flow rate of the base material (liquid A)", "increase the flow rate of the plasticizer (liquid B)", or "maintain the flow rates of the base material (liquid A) and plasticizer (liquid B)") is transmitted to the control signal generation block 11H via the signal transmission line SL35.

[0048] The control signal generating block 11H has the function of transmitting the necessary control signal to the grout pump 42 (pump for pumping material) of the base material supply system 40 via the signal transmission line SL36 and / or to the grout pump 52 (pump for pumping material) of the plasticizer supply system 50 via the signal transmission line SL37 based on the judgment result of the judgment block 11G. The base material side grout pump 42 and the plasticizer side grout pump 52 receive control signals from the control signal generating block 11H and adjust (increase, decrease, maintain) the flow rates of the base material (liquid A) and the plasticizer (liquid B), respectively. As a result, the flow value FR of the plasticizer grout material can be maintained within a range of flow values ​​that suit the construction conditions.

[0049] The flowchart in FIG. 16 shows the procedure for adjusting the flow value in the second embodiment. Although not shown in Fig. 16, before the injection of the plastic grout material, the γ-τ characteristics of each of three different types of plastic grout materials with known flow values ​​F are determined (shear rate-shear stress characteristic determination step) and the yield stress τy is determined (step of determining the yield stress τy of the three types of plastic grout materials) in a similar procedure to that shown in Fig. 13. This control is performed by the γ-τ characteristics and τy determination block 11B. Similarly, before the injection of the plastic grout material, the function or characteristics of the yield stress and flow value F of three types of plastic grout material with known flow values ​​are determined in the same procedure as shown in Fig. 13 (yield stress-flow value function determination process). This control is performed in F=F(τy) determination block 11C.

[0050] In step S31 of FIG. 16, the pipe diameter D and section length L of the pressure transfer pipe are input to the input device 20 (see FIG. 15). In step S32, the flow rate Q and flow velocity V of the plastic grout material are calculated based on the measurement results of the flow meter 43 (see Figure 15) installed in the base material supply system 40 and the measurement results of the flow meter 53 (see Figure 15) installed in the plastic material supply system 50 (a process of calculating the flow rate Q and flow velocity V of the plastic grout material for which the flow value is to be determined). In step S33, the pressure loss ΔP is calculated from the measurement results of the first and second pressure sensors 62A, 62B (see FIG. 15) (a step of calculating the pressure loss ΔP of the plastic grout material whose flow value is to be determined). The controls in steps S32 and S33 are executed by the Q, V, ΔP calculation block 11A. Here, steps S31 to S33 can be executed in any order, or a plurality of steps can be executed simultaneously.

[0051] In step S34, the shear rate γ and shear stress τ are calculated from the pipe diameter D of the pressure pipe, the section length L, the flow rate Q (flow velocity V), and the pressure loss ΔP using the above formulas (1) and (2) (a process of calculating the shear rate γ and shear stress τ of the plastic grout material for which the flow value is to be determined). The control of step S34 is executed by the γ, τ calculation block 11D. In the next step S35, the shear rate γ (γ = γ0) and shear stress τ (τ = τ0) of the plastic grout material whose flow value is to be determined, calculated in step S34, are plotted on the γ-τ characteristic diagram of three types of plastic grout material (flow values ​​F = 100 mm, 120 mm, 140 mm) determined at a stage prior to the injection of the plastic grout material, to determine the characteristic line R and yield stress τR of the plastic grout material whose flow value is to be determined (step of determining the yield stress τR of the plastic grout material whose flow value is to be determined: see Figure 9). The control of step S35 is carried out by the τR determination block 11E, and the process then proceeds to step S36.

[0052] In step S36, the yield stress τR determined in step S35 is used to calculate the function of the yield stress τy determined before the injection of the plastic grout material and the flow value F (a function that expresses the flow value F as the reciprocal of the square root of the yield stress τy: F=a / (τy) 1 / 2 ) to determine the flow value FR (step of determining the flow value of the plastic grout material whose flow value is to be determined, see FIG. 10). Alternatively, the flow value FR of the plastic grout material whose flow value is to be determined is determined using the characteristics corresponding to the function. The control of step S36 is executed by the flow value determination block 11F, and then it proceeds to step S37.

[0053] In step S37, it is determined whether the flow value FR determined in step S36 is within the range of the flow values suitable for the construction conditions (within the set range). As a result of the determination in step S37, if the flow value FR of the plastic grout material for which the flow value is to be determined is within the range of the flow values suitable for the construction conditions (FR is within the set range), it proceeds to step S38. If the flow value FR is smaller than the set range (FR < set range), it proceeds to step S39. If the flow value FR is larger than the set range (set range < FR), it proceeds to step S40. The control of step S37 is executed by the determination block 11G.

[0054] In step S38 (FR is within the set range), the flow rate of the base material (liquid A) and the flow rate of the plastic material (liquid B) are maintained. In step S39 (FR < set range), the flow rate of the base material (liquid A) is increased (the flow rate of liquid A is increased). In step S40 (set range < FR), the flow rate of the plastic material (liquid B) is increased (the flow rate of liquid B is increased). The control from step 38 to step S40 is performed by the control signal generation block 11H using the grout pumps 42 and 52 in the base material supply system 40.

[0055] In step S41, it is determined whether to end the construction of the injection method for the plastic grout material. If the determination result in step S41 is "end" (step S41 is "Yes"), the control in FIG. 16 is ended. On the other hand, if the determination result in step S41 is "not end (continue)" (step S41 is "No"), it returns to step S31 (or step 32, step S33).

[0056] 15 and 16, the flow value of the plastic grout material can also be determined with a high degree of accuracy suitable for practical use. The determined flow value FR is compared with a set range, and if the determined flow value FR is smaller than the set range, the flow rate of the base material (liquid A) is increased, if the determined flow value FR is larger than the set range, the flow rate of the plasticizer (liquid B) is increased, and if the determined flow value FR is within the set range, the flow rates of the base material (liquid A) and the plasticizer (liquid B) are maintained, thereby always maintaining the flow value of the plastic grout material at an appropriate value. Other configurations, functions and effects of the second embodiment are the same as those of the first embodiment shown in FIGS.

[0057] It should be noted that the illustrated embodiments are merely examples and are not intended to limit the technical scope of the present invention. For example, although the illustrated embodiment uses three types of grout materials with known flow values, it is also possible to use four or more types of grout materials. [Explanation of symbols]

[0058] 10, 11...Control device 10A···Shear rate-shear stress characteristics and yield stress determination block 10B: Yield stress-flow value function determination block 10C...Shear rate calculation block 10D...Shear stress calculation block 10E···Yield stress determination block 10F···Flow value determination block 10G... Flow rate determination block 10H···Database (storage device) 11A Flow rate, flow velocity and pressure loss calculation block 11B: Shear rate-shear stress characteristics and yield stress determination block 11C···Yield stress-flow value function determination block 11D...Shear velocity / shear stress calculation block 11E... Yield stress determination block 11F···Flow value determination block 11G...Decision Block 11H Control signal generation block 11I···Database (storage device) 40...Base material supply system 50...Plastic material supply system 42, 52... Material pump (grout pump) 43, 53...flow meter 61. Mixing device (static mixer) 62A, 62B... Pressure sensor 100....System for determining flow values ​​of plastic grout materials 101···Injection Construction System

Claims

1. a shear rate-shear stress characteristic and yield stress determination block having a function of determining the shear rate-shear stress characteristic and yield stress of multiple types of plastic grout materials having different flow values; a yield stress-flow value function determination block having a function of determining the flow value of the plurality of types of plastic grout materials as a function or characteristic of the reciprocal of the square root of the determined yield stress; a shear rate calculation block having a function of calculating the shear rate of a plastic grout material from the flow rates of the plastic grout material whose flow value is to be determined and multiple types of plastic grout materials having different flow values; a shear stress calculation block having a function of calculating the shear stress of a plastic grout material from the pressure loss of the plastic grout material whose flow value is to be determined and a plurality of types of plastic grout materials having different flow values; a yield stress determination block having a function of determining the yield stress of a plastic grout material whose flow value is to be determined using the shear rate-shear stress characteristics determined in the shear rate-shear stress characteristics and yield stress determination block; A system for determining the flow value of a plastic grout material, characterized in that it has a flow value determination block having the function of determining the flow value of the plastic grout material for which the flow value is to be determined, using the yield stress determined in the yield stress determination block and the function or characteristic determined in the yield stress-flow value function determination block.

2. A construction system for an injection method in which a two-component mixed plastic grout material is injected, the plastic grout material containing two types of materials, the flow value increases when there is a large amount of one material, and the flow value decreases when there is a large amount of the other material, Each system is equipped with a material pump and a flow meter. a mixing device and a pressure sensor are interposed at a confluence of the base material supply system and the plasticizer supply system or downstream thereof, and the pressure sensors are disposed at two different positions; The control device includes: A function of calculating the flow rate and flow velocity of the plastic grout material from the measurement results of the flow meter installed in the base material supply system and the flow meter installed in the plastic material supply system; A function to calculate pressure loss from the measurement results of pressure sensors at two different locations, A function to determine the shear rate-shear stress characteristics of multiple types of plastic grout materials with different flow values; determining the yield stresses of the plurality of plastic grout materials and determining the flow values ​​of the plurality of plastic grout materials as a function or characteristic of the reciprocal of the square root of the determined yield stresses; A function of calculating the shear rate and shear stress of a plastic grout material from the flow rate and pressure loss of the plastic grout material whose flow value is to be determined; A function for determining the yield stress of a plastic grout material whose flow value is to be determined using the determined shear rate-shear stress characteristics; a function for determining a flow value of a plastic grout material for which the flow value is to be determined, using the determined yield stress and the determined function or characteristic; A construction system for an injection method characterized by having the function of comparing a determined flow value with a range of flow values ​​that are suitable for construction conditions, increasing the flow rate of the base material if the determined flow value is smaller than the range of flow values, increasing the flow rate of the plasticizer if the determined flow value is larger than the range of flow values, and maintaining the flow rate of the base material and the flow rate of the plasticizer if the determined flow value is within the range of flow values.

3. a shear rate-shear stress characteristic determination step of determining the shear rate-shear stress characteristics of multiple types of plastic grout materials having different flow values; a yield stress-flow value function determination step for determining the yield stresses of the plurality of plastic grout materials and determining the flow values ​​of the plurality of plastic grout materials as a function or characteristic of the reciprocal of the square root of the determined yield stresses; a shear rate and shear stress calculation step of calculating the shear rate and shear stress of the plastic grout material from the flow rate and pressure loss of the plastic grout material whose flow value is to be determined; a yield stress determination step of determining a yield stress of a plastic grout material whose flow value is to be determined using the shear rate-shear stress characteristics determined in the shear rate-shear stress characteristics determination step; A method for determining the flow value of a plastic grout material, characterized by comprising a flow value determination step of determining the flow value of the plastic grout material for which the flow value is to be determined, using the yield stress determined in the yield stress determination step and the function or characteristic determined in the yield stress-flow value function determination block.

4. An injection method for injecting a two-component mixed plastic grout material, the plastic grout material containing two types of materials, the flow value of which increases when there is a large amount of one material, and the flow value of which decreases when there is a large amount of the other material, The system includes a base material supply system and a plasticizer supply system, each of which is equipped with a material pressure-feeding pump and a flow meter, and a mixer and a pressure sensor are installed at the confluence of the base material supply system and the plasticizer supply system or downstream thereof, and the pressure sensors are located at two different positions; determining shear rate-shear stress characteristics of a plurality of types of plastic grout materials having different flow values ​​prior to injection, determining yield stresses of the plurality of types of plastic grout materials, and determining flow values ​​of the plurality of types of plastic grout materials as a function or characteristic of the reciprocal of the square root of the determined yield stresses; a step of calculating the flow rate and flow velocity of the plastic grout material from the measurement results of the flow meter installed in the base material supply system and the flow meter installed in the plastic material supply system when injecting the plastic grout material; A step of calculating a pressure loss from measurement results of pressure sensors at two different positions; calculating the shear rate and shear stress of the plastic grout material from the flow rate and pressure loss of the plastic grout material whose flow value is to be determined; determining the yield stress of the plastic grout material whose flow value is to be determined using the determined shear rate-shear stress characteristics; determining a flow value of the plastic grout material for which the flow value is to be determined using the determined yield stress and the determined function or characteristic; An injection method characterized by comprising a step of comparing the determined flow value with a range of flow values ​​that are suitable for the construction conditions, increasing the flow rate of the base material if the determined flow value is smaller than the range of flow values, increasing the flow rate of the plasticizer if the determined flow value is larger than the range of flow values, and maintaining the flow rate of the base material and the flow rate of the plasticizer if the determined flow value is within the range of flow values.

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