JP2675129B2 - Measuring device for crushing range in jet injection method - Google Patents

Description

Description: [Industrial application] The present invention relates to a crushing range measuring device in a jet injection method.

[Prior art] Measurement of the crushing range of the ground and rock in the construction of the injection pouring method is one of the basic techniques for quality control of finished columnar solidified bodies and improvement of construction method efficiency.

Therefore, when excavating underground continuous walls and cast-in-place piles,
Usually, the crushing range is measured by the reflection of ultrasonic waves in bentonite liquid and reflected in the construction management.

[Problems to be Solved by the Invention] However, as in the case of the jet injection method, in a suspension of cement particles or soil particles, and when the concentration is extremely high, attenuation occurs even if ultrasonic waves are transmitted. Can't get big and accurate results. For this reason, technological developments are being made on increasing the output of ultrasonic waves, using parabolic antennas for efficiently catching the reflected liquid, using stacking methods, and processing the obtained data. However, its practical application requires further research, and has the drawback that the device becomes complicated.

It is an object of the present invention to provide a crushing range measuring device in a blast injection method having a high measurement accuracy and a simple structure.

[Knowledge] When ultrasonic waves are sent in a multi-layer jet of bentonite liquid or water, and when the waves reflected by the wall of the jet propagating in the same jet are received, the attenuation of the ultrasonic waves is extremely small and clear data is obtained. It can be obtained and the measuring device becomes relatively simple. The present invention has been made based on such findings.

[Means for Solving the Problem] According to the crushing range measuring device in the injection and injection method of the present invention, the nozzle for injecting high-pressure water or bentonite liquid and the protective cylinder in the central inner part of the nozzle are surrounded. An ultrasonic wave transmitter / receiver provided, a transmission / reception cable for connecting the wave transmitter / receiver to the ground, a pump for pumping water or bentonite liquid to the nozzle, a data transmitter / receiver, and an ultrasonic oscillator,
A data recorder is provided.

It is preferable that the nozzle is composed of a central high-pressure nozzle and an annular low-pressure nozzle provided around the high-pressure nozzle, and these nozzles and an ultrasonic wave transmitter / receiver constitute an injection device.

Further, the injection device is attached to the lower end of the underwater monitor according to the known technique and installed at a predetermined depth of the guide hole when the measurement is performed at the time of performing the injection injection method, and when the measurement is performed after the method is performed, the lower end of the rod. It is preferable that the crushing hole is attached to the bottom of the crushing hole.

[Operation] In the method for measuring the crushing range in the injection injection method and the apparatus therefor configured as described above, the injection device is rotated and the pump is operated to inject water or bentonite liquid from both nozzles to transmit and receive ultrasonic waves. The ultrasonic wave is oscillated from the wave device, the reflected wave from the wall of the crush hole is received, and the inside diameter of the crush hole is measured by a device installed on the ground based on the oscillated wave and the received wave.

At this time, the ultrasonic waves are protected from the influence of the nozzle jet by the protective cylinder, and propagate and reflect in the nozzle jet,
Very low attenuation and accurate measurement values are obtained.

Therefore, since high-frequency ultrasonic waves are transmitted and received to obtain clear recording, the reading error is small.

In addition, accurate data can be obtained even on the ground where the difference in acoustic impedance is extremely small, such as slurry and ground.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

 FIG. 1 shows an apparatus embodying the present invention.

In the figure, a triple pipe 3 and a triple pipe swivel 4 are sequentially connected above the underwater monitor 2 inserted into the guide hole 1 at a predetermined depth. The triple pipe 3 is rotatably supported by a support device 5, and the triple pipe swivel 4 is suspended by a crane 6. By moving the triple pipe swivel 4 up and down by the crane 6, the underwater monitor 2 is moved up and down. It has become so. And the triple tube swivel 4
It is connected to a grout pump, a compressor, and a high-pressure water pump (not shown).

The measuring device is an injection device 13 provided at the lower end of the underwater monitor 2 and provided with an ultrasonic wave transmitter / receiver 18 described later, a transmission / reception cable 7 connected to the ultrasonic wave transmitter / receiver 18, and a lower portion of the support device 5. A data transmitter / receiver 8 to which a transmission / reception cable 7 is connected, a pump 9 for sending water or bentonite liquid to a jetting device 13 installed on the ground, a radio transmitter / receiver 10, an ultrasonic oscillator 11 and a data recorder 12. It consists of

2 and 3, the injection device 13 includes a low-pressure nozzle that injects low-pressure water or bentonite liquid around a high-pressure nozzle 14 that injects high-pressure water or bentonite liquid.
14 is provided in an annular shape and is connected to the above-ground pump 9 by hoses 16 and 17, respectively.

At the back of the center of the high-pressure nozzle 14, an ultrasonic transducer 18
Is provided, and the surrounding area is covered with a protective cylinder 19 so as to prevent the influence of a high-pressure jet of water or bentonite liquid.
The ultrasonic wave transmitter / receiver 18 is used for the transmission / reception cable 7
Is connected to the data transmitter / receiver 8.

There are two types of measurement, a method of performing in real time at the time of construction of a jet injection method such as a column jet construction method and a method of performing after the construction of the construction method, but the present invention can be implemented in any case.

FIGS. 4 (a) and 4 (b) show a mode of implementation in real time.

First, up to the construction depth that is the target of construction, for example, diameter 15
A guide hole 1 of about cm is formed (Fig. 4 (a)).

Next, the underwater monitor 2 provided with the injection device 13 at the lower end is installed at a predetermined depth (FIG. 4 (b)).

Then, the column jet 20 is jetted from the underwater monitor 2 to crush the ground, and the ultrasonic transducer is jetted while jetting water or bentonite liquid from the nozzles 14 and 15 of the jetting device 13.
The ultrasonic wave from 18 is oscillated, and the oscillated wave, the reflected wave from the hole wall of the crushing hole 21 and the ground equipment 10 to 12 are processed, and the crushing hole 21
The inner diameter of is measured (Fig. 3 (c)). At this time, even if the suspension particles of the injection material such as cement milk of the column jet method are large and the viscosity is high, the ultrasonic waves put on the jet of water or bentonite liquid has very little attenuation and is extremely accurate. Data can be obtained.

5 (a) to 5 (c) show a mode in which construction and measurement are performed with a time lag.

First, after the injection and injection method such as the column jet method is completed, the construction machine 22 and the like are removed (Fig. 5 (a)).

Next, the injection device 13 is attached to the lower end of the rod 23, and is installed at the bottom of the crushing hole 21 filled with the slurry 24 such as cement milk (Fig. 5 (b)).

Next, the rod 23 is rotated, the pump 9 on the ground is operated, and ultrasonic waves are oscillated from the ultrasonic wave transmitter / receiver 18 to measure the inner diameter of the drilled hole 21 in the same manner as described above (FIG. 5 (c)). .

[Effects of the Invention] Since the present invention is configured as described above,
The following effects are obtained.

During the injection injection method such as the column jet method, the suspension particles such as cement milk are large as the injection material, and the attenuation of ultrasonic waves is very small even in a highly viscous slurry, and extremely accurate data can be obtained. it can.

Further, the jet of water or bentonite liquid, which is the propagation path of ultrasonic waves and reflected waves, is a water jet or bentonite liquid, for example, for non-collapseable cohesive soil or collapsible sand ground, depending on the type of ground. Can be used properly with a jet.

In addition, accurate data can be obtained even when constructing the ground such as the slurry and the ground where the difference in acoustic impedance is extremely small.

In addition, it is possible to obtain accurate data during and after construction.

Further, since the construction can be performed while observing the crushing range of the ground, it is possible to economically use the injection material such as cement milk, accurately improve the ground only within the planned range, and improve the construction efficiency.

In addition, the nozzle is configured as a double nozzle consisting of a high-speed nozzle in the center and a low-speed nozzle in an annular shape (if necessary, it is a double or triple nozzle with a triple or more) to increase the effective flight distance of the central jet.
It is possible to measure up to a range of about 2 m even in a highly viscous slurry exceeding 1000 centipoise.

In addition to the injection and injection method, the suspended particles are large,
It can also be applied to a hole bottom of a cast-in-place pile having a large apparent specific gravity.

Further, since the ultrasonic oscillator is provided inside the nozzle, the structure is relatively simple.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an example of an apparatus for carrying out the present invention, FIG. 2 is a side sectional view showing an injection apparatus, FIG. 3 is a view taken in the direction of arrow A in FIG. 2, and FIGS. (C) is a work order diagram showing a mode of carrying out in real time, and FIGS. 5 (a) to (c) are work order diagrams showing a mode of carrying out construction and measurement with a time lag. 7 ... Transmission / reception cable, 8 ... Ultrasonic transceiver, 9 ...
… Pump, 10… Wireless transceiver, 11… Ultrasonic oscillator,
12 ... Data recorder, 13 ... Injection device, 14 ... High pressure nozzle, 15 ... Low pressure nozzle, 18 ... Ultrasonic wave transceiver, 19 ...
… Protective cylinder, 21 …… Crush hole

Claims (1)

(57) [Claims] 1. A nozzle for injecting high-pressure water or bentonite liquid, an ultrasonic wave transmitter / receiver provided in a central inner part of the nozzle surrounded by a protective cylinder, and a transmitter / receiver for connecting the wave transmitter / receiver to the ground. An apparatus for measuring a crushing range in a jet injection method, comprising: a cable for use with a pump, a pump for sending water or bentonite liquid to the nozzle under pressure, a data transmitter / receiver, an ultrasonic oscillator, and a data recorder.