JPH09302933A - Method and equipment for detecting concrete-placing top end - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detecting method and an equipment capable of continuously detecting the change of a placing top end. SOLUTION: An optical fiber 12 for a temperature sensor generating scattered light having intensity corresponding to a temperature to the incidence of pulse light is inserted in the depth direction in a space 1, into which concrete 7 is injected. Pulse light is projected from the upper end of the optical fiber 12, scattered light generated in the optical fiber 1 in response to incident pulse light is detected at the upper end, and a distance from the upper end to the place of the generation of scattered light is obtained on the basis of the time up to the detection of each scattered light after the incidence of pulse light and the temperature of the place of the generation of scattered light is acquired on the basis of the intensity of scattered light, thus measuring temperature distribution in the depth direction of the space 1. A depth place, where the rate of a temperature change in the depth direction of the space 1 is maximized, is computed from the temperature distribution measured by pulse-light incidence at the time of the pouring of concrete 7, and the position of a placing top end is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for detecting the top of concrete, and more particularly to a method and an apparatus for detecting the top of the cast concrete based on the temperature difference between before and after placing the concrete. Regarding

[0002]

2. Description of the Related Art In a construction work for a concrete underground wall, concrete 7 is continuously poured by a concrete placing pipe 5 into a pre-drilled underground hole 1a, as shown in FIG. FIG. 4 shows a construction method in which the underground hole 1a is filled with the stabilizing liquid 4 before the concrete 7 is poured, and the concrete 7 is sequentially poured from the bottom of the underground hole 1a by substituting the stabilizing liquid 4. Conventionally, as a method of detecting the top end of the cast concrete 7 when pouring concrete into the underground hole 1a, as shown in FIG. 4, a human 2 uses a sounding rope 8 with a weight 10 or a sounding rod based on the feeling of a hand. A method (hereinafter referred to as a rod measurement method) for suspending the concrete 7 in the underground hole 1a to the boundary between the stabilizing liquid 4 and visually reading the scale of the sounding cable 8 etc. at the time of suspension is implemented. There is. Further, a pressure sensor is hung near the boundary between the cast concrete 7 and the stabilizing liquid 4 in the underground hole 1a, and the boundary between the concrete 7 and the stabilizing liquid 4 is detected by the pressure sensor based on the difference in density between the concrete 7 and the stabilizing liquid 4. However, a method (hereinafter, referred to as a pressure type detection method) of detecting the driving top end from the hanging position of the pressure sensor at the time of detection is also implemented. Further, the applicant has arranged a plurality of thermocouples in the underground hole 1a at predetermined intervals in the depth direction, and from the temperature difference between the thermocouples before and after the grout injection, the top end of the cast grout. An anchor grout crown detection method for detecting the position was developed and disclosed in Japanese Patent Laid-Open No. 6-347306.

[0003]

However, since the conventional rod measuring method is a measuring method that depends on human senses, the top end position may vary depending on the measurer. Further, it is expected that a method for detecting the top end that can be used for automating the concrete placing construction will be developed, but it is difficult to automate the construction by the rod measuring method that requires visual reading of the sounding cable 8 or the like. On the other hand, the conventional pressure type detection method has a problem that the slime of the stabilizing liquid 4 or the concrete 7 which is an obstacle to the normal pressure detection tends to stick to the pressure sensor, and the suspended position of the pressure sensor is placed in the concrete 7 There is also a problem in that it must be moved following the rise of the crown of.
These problems are factors that make it difficult to automate the driving construction using the pressure detection method. JP-A-6-347306
The invention of No. 1 detects the top position of the driving by the thermocouples arranged at a predetermined interval, but the arrangement of the thermocouple must be discontinuous, and continuous detection of changes in the top position is difficult. is there. Continuous detection of changes in pouring top position is indispensable for automating pouring work, especially for adjusting flow rate of pouring concrete.

Therefore, an object of the present invention is to provide a method and apparatus for detecting a concrete pouring top capable of continuously detecting changes in the pouring top position.

[0005]

With reference to the embodiment shown in FIG. 1 and the flow chart shown in FIG. 2, a concrete pouring top detecting method according to the present invention is a scattered light having an intensity corresponding to temperature with respect to incidence of pulsed light. The temperature sensor optical fiber 12 for generating the light is inserted in the depth direction of the space 1 into which the concrete 7 is poured, pulsed light is incident from the upper end of the optical fiber 12, and scattered light generated in the optical fiber 12 according to the incident pulsed light. Is detected at the upper end, the distance from the upper end to the scattered light generation position is obtained based on the time from the incidence of the pulsed light to the detection of each scattered light, and the scattered light generation position of the scattered light generation position based on the intensity of the scattered light. The temperature distribution in the depth direction of the space 1 is measured by obtaining the temperature, and the temperature change rate in the depth direction of the space 1 is maximum from the temperature distribution measured by the pulsed light injection when the concrete 7 is injected. The depth position at which it is made is calculated as a top end position of the pouring concrete.

Further, referring to FIG. 1, the concrete pouring top detector of the present invention generates scattered light having an intensity corresponding to temperature in response to the incidence of pulsed light, and in the space 1 into which the concrete 7 is poured. The temperature sensor optical fiber 12 inserted in the depth direction, an incident means connected to one end of the optical fiber 12 for injecting pulsed light from the one end, and scattered light generated in the optical fiber 12 according to the pulsed light is detected at the one end. The temperature of the scattered light generation position based on the intensity of the scattered light and the distance measuring means for obtaining the distance from the one end to the scattered light generation position based on the time from the incidence of the pulsed light to the detection of each scattered light A temperature measuring device 13 having a temperature measuring means for obtaining the temperature distribution, and a temperature measuring device 13 connected to the temperature measuring device 13 to measure the temperature distribution in the longitudinal direction of the optical fiber 12 from the distance and the temperature. Longitudinal rate of temperature change of Iba 12 is made of an arithmetic unit 16 for calculating a position of maximum as concrete top end position.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment in which the method and apparatus for detecting the top of the present invention is applied to concrete placing on an underground wall, and FIG. 2 is an example of a flow chart of the method for detecting the top of the placing. Indicates. Reference numeral 3 in FIG. 1 indicates a reinforcing bar cage provided in the underground hole. However, the present invention is not limited to being applied to underground holes, but can be applied to other concrete pouring spaces. To explain the method of the present invention with reference to the flow chart of FIG.
At 201, an optical fiber 12 for temperature sensor is inserted into a concrete placing space (hereinafter, simply referred to as space) 1 in the depth direction. The temperature sensor optical fiber (hereinafter, may be simply referred to as an optical fiber) 12 generates scattered light having an intensity corresponding to the temperature according to the pulsed light incident from one end thereof. Conventionally, it is known that the intensity of Raman scattered light contained in scattered light depends on temperature sensitively, and the intensity of Raman scattered light generated in the optical fiber 12 in response to pulsed light is detected at one end of the optical fiber 12. As a result, the temperature at the position where the scattered light is generated can be obtained.
Further, the distance from one end of the optical fiber 12 to the generation position of the scattered light is obtained based on the time from the incidence of the pulsed light to the detection of each scattered light and the traveling speed of the pulsed light and the scattered light in the optical fiber 12.

The temperature measuring device 13 connected to one end of the optical fiber 12 of FIG. 1 includes means for injecting pulsed light into the optical fiber 12, means for detecting scattered light generated in the optical fiber 12, and incidence of pulsed light. It has a distance measuring means for obtaining the distance from the one end to the scattered light generating position based on the time until the detection of scattered light, and a temperature measuring means for obtaining the temperature of the scattered light generating position based on the intensity of the detected scattered light. It is a thing. Such a temperature measuring device 13 and the optical fiber 12 are, for example, an optical fiber temperature radar (FiberOptic Tem).
perature Laser Radar) and belongs to the prior art. In FIG. 1, the distance and the temperature measured by the temperature measuring device 13 are sent to the calculating means 16, and the calculating means 16 determines the temperature distribution in the length direction of the optical fiber 12.
An example of the calculation means 16 is a computer having a temperature distribution calculation program built therein. Since the optical fiber 12 extends in the depth direction of the space 1, it is possible to measure a continuous temperature distribution in the depth direction of the space 1 from the temperature distribution in the length direction of the optical fiber 12. Display means 18 for displaying the temperature distribution and the like is connected to the computing means 16 of FIG.

After inserting the optical fiber 12 into the space 1,
In step 202, pouring of concrete 7 is started, and in step 203, pulse light is incident from one end of the optical fiber 12,
In step 204, each scattered light is detected, the distance from one end of the optical fiber 12 to the scattered light generation position and the temperature at the scattered light generation position are obtained, and in step 205, the temperature distribution in the depth direction of the space 1 is measured. . Figure 3 is a step
An example of the display means 18 that graphically displays the temperature distribution obtained in 205 is shown. In the graph of FIG. 3, the vertical axis represents the depth of the space 1,
The horizontal axis shows the temperature distribution.

As shown in the graph of FIG. 3, step 205
The temperature distribution in the depth direction of the space 1 measured at 1 has a relatively low temperature upper portion and a relatively high temperature lower portion. That is, in FIG. 1 showing an embodiment of a construction method in which concrete 7 is placed by replacing the stabilizing liquid 4 with the stabilizing liquid 4, the temperature of the stabilizing liquid 4 is about 20 ° C.
While the ordinary concrete 7 has a relatively low temperature, the ordinary concrete 7 generates heat due to the chemical reaction between the constituent materials to a relatively high temperature of about 60 ° C., so that the temperature distribution of FIG. 3 is obtained. Figure 3 shows an example of concrete 7 with a low calorific value. Even in this case, the temperature of concrete 7 rises to about 30 ° C, which is a relatively high temperature for stable water 4, so the temperature distribution shown in Figure 3 is obtained. . However, the stabilizing solution 4 is not essential for obtaining the temperature distribution shown in FIG.

In step 206 of FIG. 2, the position where the rate of temperature change is maximum is calculated as the pouring top position from the temperature distribution obtained in step 205 by the arithmetic unit 16. As can be seen from the temperature distribution graph of FIG. 3, the boundary position between the relatively high temperature concrete 7 and the relatively low temperature stabilizing liquid 4, that is, the position of the maximum temperature change rate corresponds to the pouring top position. is there. The found pouring top position is displayed as a marker that moves up and down with a certain width within a frame corresponding to the depth of the space 1 and / or a digital number, for example, as shown in the display means 18 in FIG. Can be displayed as (step 207). The present invention can obtain an accurate pouring top position from the continuous temperature distribution in the depth direction of the space 1, and step 203
By repeating steps 206 to 206 at predetermined time intervals, the rising speed of the pouring top position can be detected.

In this way, it is possible to achieve the object of the present invention to provide a "concrete pouring top detecting method and device capable of continuously detecting changes in pouring top position".

[0013]

FIG. 1 shows an embodiment in which an optical fiber 12 of 200 m is used, and a winding drum 14 fixed to one end of the optical fiber 12 and a length of winding or unwinding the optical fiber 12 with respect to the winding drum 14. Length measuring instrument
15 are provided. In this case, the measurement length of the length measuring device 15 is input to the calculating means 16, and the calculating means 16 causes the temperature measuring machine 13
The depth in the space 1 of the scattered light generation position is obtained from the measurement distance by the length measuring device 15 and the length measured by the length measuring device 15, and the depth direction of the space 1 is calculated from the depth in the space 1 and the temperature measured by the temperature measuring means 13. It is possible to calculate the temperature distribution of the above and calculate the position where the temperature change rate in the depth direction is the maximum as the concrete top position. In the embodiment of FIG. 1, the weight 10 is attached to the payout end of the optical fiber 12 in order to suspend the optical fiber 12 in the vertical direction in the space 1.

In the embodiment shown in FIG. 1, the concrete flow rate control means 20 connected to the calculation means 16 for controlling the concrete pouring flow rate into the space 1, and the pulse light is incident on the incidence means of the temperature measuring instrument 13 at predetermined time intervals. Sampling means for making, and speed calculation means for calculating the rising speed of the top end position based on the concrete top end position calculated by the calculation means 16 at the predetermined time interval are provided, and the concrete top end position and / or the top end position By inputting the rising speed to the flow rate control means 20, the rising speed of the concrete top end position is controlled. An example of the sampling means and the speed calculation means is a computer that incorporates a sampling program and a speed calculation program, respectively. In FIG. 1, the computing means 16 is a computer, and a sampling program and a speed calculation program are built in the computer,
The computer also serves as sampling means and speed calculation means.

Referring to the flow chart of FIG. 2, the sampling means causes the pulsed light to be incident at predetermined time intervals, for example, one minute intervals.
By starting (step 203), steps 203 to 2
10 processes are repeated at a predetermined time interval. That is, when controlling the concrete flow rate, step 208 to step 2
In step 09, the ascending speed of the top end position is calculated by the speed calculating means from the previous top end position, the current top end position, and the predetermined time interval. In step 210, the top end position and / or the ascending speed of the top end position is input to the flow rate control means 20, and the flow rate control means 20 controls the concrete pouring flow rate of the concrete pouring device 6 to be optimum. The display means 18 of FIG. 3 is provided with a column for displaying the concrete pouring flow rate by digital numbers.

[0016]

As described above, according to the method and apparatus for detecting a concrete pouring top of the present invention, an optical fiber for temperature sensor is inserted in the depth direction of the concrete pouring space to measure the temperature distribution in the depth direction. However, since the depth position where the temperature change rate in the depth direction is maximum is calculated as the pouring top position, the following remarkable effects are achieved.

(A) It is possible to detect the accurate top end position of the poured concrete in real time from the continuous temperature distribution in the depth direction of the concrete poured space. (B) By repeating the detection of the concrete pouring top position at predetermined time intervals, the rising speed of the top position can be obtained. (C) By feeding back the concrete pouring top position and / or the rising speed of the top position to the concrete pouring device or the like, the concrete pouring flow rate can be automatically controlled.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of one embodiment of the present invention.

FIG. 2 is a flow chart showing an example of the method of the present invention.

FIG. 3 is an explanatory diagram showing an example of a display of a display unit.

FIG. 4 is an explanatory diagram of an example of a conventional concrete crown detection method.

[Explanation of symbols]

 1 ... Placing space 2 ... Human being 3 ... Reinforcing bar 4 ... Stabilizing liquid 5 ... Concrete placing pipe 6 ... Concrete placing device 7 ... Concrete 8 ... Sounding rope 9 ... Winding drum 10 ... Weight 12 ... Temperature sensor optical fiber 13 ... Temperature measuring instrument 14 ... Winding drum 15 ... Length measuring instrument 16 ... Computing means 18 ... Displaying means 20 ... Flow rate controlling means.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location G01S 17/88 G01S 17/88 Z (72) Inventor Nobuyuki Matsui 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd.

Claims (5)

[Claims] 1. An optical fiber for a temperature sensor, which generates scattered light having an intensity corresponding to temperature in response to the incidence of pulsed light, is inserted in a depth direction in a space into which concrete is injected, and pulsed light is incident from the upper end of the optical fiber. Then, the scattered light generated in the optical fiber according to the incident pulsed light is detected at the upper end, and the distance from the upper end to the scattered light generation position is based on the time from the incidence of the pulsed light to the detection of each scattered light. The temperature distribution in the depth direction of the space is measured by determining the temperature of the scattered light generation position based on the intensity of the scattered light and the space from the temperature distribution measured by the pulsed light injection at the time of concrete injection. The method for detecting the top of concrete pouring, which is calculated by calculating the depth position where the rate of temperature change in the depth direction is maximum as the top position of the pouring concrete. 2. An optical fiber for a temperature sensor which generates scattered light having an intensity depending on temperature upon incidence of pulsed light and is inserted in a depth direction in a space into which concrete is poured, the optical fiber being connected to one end of the optical fiber. An incident means for injecting pulsed light from one end, a detection means for detecting scattered light generated in the optical fiber according to the pulsed light at the one end, and the one end based on the time from the incidence of the pulsed light to the detection of each scattered light From a temperature measuring device having a distance measuring means for obtaining a distance to the scattered light generating position and a temperature measuring means for obtaining a temperature at the scattered light generating position based on the intensity of the scattered light, and the temperature measuring device connected to the temperature measuring device. The position where the temperature distribution in the length direction of the optical fiber is measured from the distance and the temperature and the temperature change rate in the length direction of the optical fiber is the maximum is the concrete ceiling. Concrete 設天 edge detecting device including a calculating means for calculating a position. 3. The concrete pouring top detecting device according to claim 2, further comprising display means connected to the computing means for displaying the concrete top position. 4. The detection device according to claim 2 or 3, wherein a winding drum fixed to one end of the optical fiber, and a length of winding or unwinding the optical fiber with respect to the winding drum, which is connected to the computing means, is set. A length measuring device for measuring is provided, the temperature distribution in the depth direction of the space is measured from the distance, the temperature, and the length by the calculating means, and the position where the rate of temperature change in the depth direction becomes maximum is determined. A concrete pouring top detector that is calculated as the concrete top position. 5. The concrete flow control means for controlling the concrete pouring flow rate to the space, which is connected to the calculating means, to the detecting device according to claim 2, and the pulse to the incident means at a predetermined time interval. Sampling means for injecting light, and speed calculation means for calculating a rising speed of the top end position of the concrete based on the top end position of the concrete calculated by the calculation means at the predetermined time interval are provided, and the concrete top position and / or the top end of the concrete are provided. A concrete pouring control system in which the ascending speed of the concrete top end position is controlled by inputting the ascending speed of the end position to the flow rate control means.