JP6085751B2 - Curing state detection method and curing time calculation method - Google Patents

Description

  The present invention relates to a curing state detection method and a curing time calculation method applicable to, for example, a grout agent.

  Conventionally, a grout agent (curable injection solution) has been used for ground improvement (see Patent Document 1). The grouting agent is in a sol state at the time of preparation, and the viscosity increases with the passage of time and eventually hardens (gels). In order to properly use the grout agent, it is necessary to simply measure the curing time of the grout agent at the construction site. As the method, the following method is known. A rotor blade or a rotor is immersed in a sol grout agent and is continuously rotated at a constant rotation speed. As the viscosity of the grouting agent increases with time, the rotational resistance of the rotor blades and rotor increases accordingly. From the value of the rotational resistance, the viscosity of the grout agent is calculated. The time from the curing start time until the viscosity of the grout agent reaches a predetermined viscosity (the time until the rotational resistance of the rotor blades and the rotor reaches a predetermined value) is defined as the curing time.

Japanese Patent Laid-Open No. 11-80731

  However, with the above method, the curing time of the grout agent could not be measured accurately. The reason is that, in the above method, since the rotor blades and the rotor continue to rotate at a constant rotational speed even when the grouting agent is hardened, the microstructure in the grout agent is gradually increased by the rotor blades and the rotor. This is thought to be because the hardening of the grout agent is delayed as compared with the case where the microgel generated in the above is broken and the rotor blades and the rotor do not rotate.

  This invention is made | formed in view of the above point, and it aims at providing the hardening state detection method and hardening time calculation method which can be utilized for the exact calculation of hardening time.

The curing state detection method of the present invention includes a rotating body that is rotationally driven with a constant torque in a detection object whose viscosity increases with time, and the rotational body that is rotationally driven with the constant torque . When the number of rotations per unit time is measured and the measured number of rotations per unit time reaches a predetermined number of rotations, the viscosity of the detection object becomes a predetermined viscosity corresponding to the predetermined number of rotations. It is characterized by detecting that it has been reached.

  In the curing state detection method of the present invention, since the torque for rotating the rotating body is constant, the rotational speed (rotational speed per unit time) of the rotating body decreases as the viscosity of the detection object increases with time. To do. Therefore, since the viscosity of the detection object and the rotational speed of the rotating body have a correlation, when the rotational speed of the rotating body reaches a predetermined rotational speed, the viscosity of the detection target becomes the predetermined rotational speed. It can be detected that a corresponding predetermined viscosity (or a predetermined viscosity range) has been reached.

  In particular, in the curing state detection method of the present invention, when the viscosity in the detection object increases with time, the rotational speed of the rotating body decreases. It is unlikely that the microgel that is gradually formed during gelation will be destroyed, and curing in the detection object is not delayed by the rotation of the rotating body.

  In the cured state detection method of the present invention, for example, when the number of rotations of a rotating body that has been rotating until then becomes zero (when stopped), the viscosity of the detection target is a predetermined viscosity (the number of rotations is zero). It is possible to detect that the viscosity has reached a certain state. Further, when the rotational speed of the rotating body has decreased to a predetermined rotational speed that is not zero, it is detected that the viscosity of the detection target has reached a predetermined viscosity (viscosity corresponding to a predetermined rotational speed that is not zero). May be.

Examples of the detection target include sol-like substances that gel with the passage of time. An example of such a substance is a grouting agent.
The material and shape of the rotating body are not particularly limited as long as the rotating body can be rotationally driven with a constant torque. It is preferable that the rotator has a constant shape and the position of the rotating shaft is constant so that the rotational resistance is the same at the same rotational speed in the detection target. Examples of the rotating body include a magnetic stirrer and the like.

  The correlation between the viscosity of the detection object and the rotational speed of the rotating body can be acquired as follows, for example. A reference liquid R1 having a known value X1 and a reference liquid R2 having a known value X2 are prepared. Here, X1 <X2. The viscosities of the reference liquid R1 and the reference liquid R2 can be accurately measured using a B-type viscometer or the like. The rotational speed when the rotating body is rotated with a constant torque in the reference liquid R1 is Y1, and the rotational speed when the rotating body is rotated with a constant torque in the reference liquid R2 is Y2 (a value smaller than Y1). And may be 0). In this case, if the rotational speed when rotating the rotating body with a constant torque in the detection target is within the range of Y2 to Y1, the viscosity of the detection target is within the range of X1 to X2. If it is Y2 or less (may be 0), the viscosity of the detection object is X2 or more, and if it is Y1 or more, the viscosity of the detection object is X1 or less.

In the curing time calculation method of the present invention, the time from the predetermined reference time T1 to the time T2 when the viscosity of the detection object reaches the predetermined viscosity, determined by the above-described curing state detection method, is calculated as the curing time. It is characterized by that.
According to the curing time calculation method of the present invention, as described above, the curing of the detection object is not delayed by the rotation of the rotating body, so that the curing time can be accurately measured.

  As the predetermined reference time T1, for example, when the detection target is a mixture of a plurality of liquids, there is a mixing completion time. Other examples of the predetermined reference time T1 include a time when the viscosity of the detection target starts to increase (gelation starts), a time when the viscosity increase rate (gelation speed) becomes larger than before, and the like. . As the time at which the viscosity of the detection object starts to increase, for example, when the detection object is a mixture of a plurality of liquids that are not cured alone, and the viscosity increases from the time of mixing, The time of mixing is mentioned.

It is explanatory drawing showing the hardening state detection method and the hardening time calculation method.

Embodiments of the present invention will be described with reference to the drawings.
1. Curing State Detection Method and Curing Time Calculation Method First, as shown in FIG. 1, a spacer 2 was placed on a magnetic stirrer 1 and a cup 11 made of transparent glass was placed thereon. The material of the spacer 2 can be appropriately selected from materials other than the ferromagnetic material (for example, wood, block, paper, and polystyrene foam).

  Next, 300 ml of a sol grout agent (curable injection solution, detection target) S is accommodated in the cup 11, and a stirrer (rotary body) 3 for the magnetic stirrer 1 is put therein. . The stirrer 3 sank to the bottom of the cup 11, and the entire stirrer 3 was immersed in the grout agent S. The stirrer 3 can be driven to rotate with a constant torque by the magnetic stirrer 1. The temperature of the grout agent S was 25 ° C., and the temperature was maintained in the subsequent steps.

  Grout agent S is prepared by sequentially adding B liquid and A to C liquid shown in Table 1. This grout agent S increases in viscosity with the passage of time from the time of adjustment and eventually gels. In Table 1, colloidal silica is Snowtex 40 manufactured by Nissan Chemical Co., Ltd., and water glass is No. 5 manufactured by Fuji Chemical Co., Ltd. The time when the grout agent S is prepared as described above is defined as time T1. The grout agent S was charged into the cup 11 immediately after time T1.

Immediately after putting the grouting agent S and the stirrer 3 in the cup 11, the stirrer 3 was continuously rotated at a constant torque by the magnetic stirrer 1. The stirring bar 3 rotated on the bottom surface of the cup 11. At this time, the stirrer 3 was continuously photographed by the video camera 4. The rotation speed of the stirrer 3 can be calculated from an image taken by the video camera 4. Although the torque for rotationally driving the stirrer 3 depends on the thickness of the spacer 2, the thickness of the spacer 2 is set in advance as follows. That is, the thickness of the spacer 2 is such that when the reference liquid R1 having a viscosity of 20 to 50 mPa · s and the stirrer 3 are put into the cup 11, the stirrer 3 can be rotated by the magnetic stirrer 1. When the reference liquid R2 having a viscosity of 260 mPa · s and the stirrer 3 were added to No. 11, the stirrer 3 could not be rotated. No. 5 water glass can be used as the reference liquid R1, and No. 1 water glass can be used as the reference liquid R2.

  When the stirrer 3 is rotated in the grout agent S, the viscosity of the grout agent S gradually increases with time, and the rotation speed of the stirrer 3 (the number of rotations per unit time) gradually decreases. Eventually, the rotation of the stirring bar 3 stopped. The time at which the rotation of the stirring bar 3 is stopped is defined as time T2. Time T2 is the time when the viscosity of the grout agent S has reached a predetermined viscosity (has reached a predetermined curing state) between the viscosity of the reference liquid R1 and the viscosity of the reference liquid R2. The time from time T1 to time T2 was defined as the gel time (curing time). Table 2 shows the gelation time in this embodiment.

Table 2 also shows the results of separately measuring the gelation time of the same grout agent S by the methods of Reference Examples 1 and 2. In the method of Reference Example 1, the grout agent S prepared at time T1 is allowed to stand, and appropriately (for example, every hour, but every 10 minutes if it is confirmed that gelation has progressed visually), B In this method, the viscosity is measured with a mold viscometer, and the time when the viscosity exceeds 100 mPa · s is defined as time T2. Since the method of Reference Example 1 requires a B-type viscometer, it is difficult to carry out simply at the construction site, but the measurement result is considered to be accurate.

  In the method of Reference Example 2, the grouting agent S prepared at time T1 is appropriately stirred (eg, every hour, however, when gelation has progressed visually) while constantly stirring with a stirring blade rotating at a constant rotational speed. This is a method in which the viscosity is measured with a B-type viscometer and the time when the viscosity exceeds 100 mPa · s is set as time T2 if it is confirmed (every 10 minutes).

2. Effect (1) Effect of Curing State Detection Method and Curing Time Calculation Method As shown in Table 2 above, the gelation time calculated by the method of the present embodiment is close to the gelation time calculated by the method of Reference Example 1, It was confirmed that it was accurate. On the other hand, the gelation time calculated by the method of Reference Example 2 was significantly longer and inaccurate than the values calculated by the method of this embodiment and Reference Example 1. This is because, as in the method of Reference Example 2, when the grout agent S is continuously stirred at a constant rotational speed until a time period immediately before gelation, the fine structure of the grout agent S (a microgel that gradually forms during gelation). ) Is destroyed and is difficult to gel.
(2) Since the method of this embodiment can be implemented with a simple apparatus, it can be easily implemented at a construction site.

In addition, this invention is not limited to the said embodiment at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.
For example, the time when the rotational speed of the stirrer 3 gradually decreases and reaches a predetermined rotational speed (a value other than 0) or within a predetermined rotational speed range may be set as the time T2. In that case, the thickness of the spacer 2 may be adjusted so that the viscosity of the grout agent S becomes a target value when the rotational speed of the stirrer 3 reaches a predetermined rotational speed.

The detection target is not limited to the grout agent, and can be appropriately selected from substances whose viscosity increases with time.
Further, the stirrer 3 is not limited to one that is rotationally driven by the magnetic stirrer 1 and may be driven by various driving forces.

1 ... Magnetic stirrer, 2 ... Spacer, 3 ... Stir bar,
4 ... Video camera, 11 ... Cup, S ... Grout

Claims (2)

A rotating body that is rotationally driven with a constant torque is installed in the detection object that increases in viscosity with time and gels.
The rotational speed per unit time of the rotating body that is rotationally driven at the constant torque is measured, and when the measured rotational speed per unit time becomes 0 , the viscosity of the detection object is the rotational speed. A curing state detection method comprising detecting that a predetermined viscosity corresponding to the number 0 is reached. From a predetermined reference time T1, was determined by cured state detecting method according to claim 1, the curing time calculation method the viscosity of the detection target to calculate the time until the time T2 has been reached the predetermined viscosity.