JP5156984B2 - Seismic wave measurement system and seismic wave measurement method - Google Patents

Description

  The present invention relates to a seismic wave measurement system and a seismic wave measurement method, and more particularly to a seismic wave measurement system and a seismic wave measurement method capable of measuring seismic waves even on soft ground.

As a method for investigating the ground condition, there is a seismic exploration method in which an artificial seismic wave is generated and measured. The seismic exploration method includes a measurement method called velocity logging for measuring seismic waves in a borehole, and the present invention relates to this velocity logging.
Compared with the seismic exploration method that investigates the seismic velocity of the ground deep from the ground surface, the velocity logging is easy to obtain high accuracy because the target ground is measured directly using the borehole.
However, measurement is a prerequisite that it is essential that the borehole be maintained in its natural state. The natural state of the borehole is also referred to as a self-standing hole, which is not a hole that has been re-excavated with a hole-holding pipe (casing) or cement.
A hole in the ground where the hole collapses immediately when the rod or casing is pulled out is called a non-standing hole.
Conventionally, since non-self-supporting holes collapse and close, it has been difficult to collect cables, rods, measuring instruments, and the like, making measurement difficult.
Further, when boring, there is often a problem that groundwater or gas / oil is ejected from the boring rod and the borehole wall or between the boreholes (casing).
Japanese Patent Laid-Open No. 06-098435

  It is an object of the present invention to provide a seismic wave measurement system and a seismic wave measurement method that enable seismic wave measurement in a non-self-sustaining hole that tends to collapse or a borehole that is expected to eject groundwater or the like.

  The present invention is a system for measuring seismic waves in an underground boring hole, and is attached to a cable rod inserted into the boring hole together with a cable along an outer peripheral portion, and attached to the tip of the boring hole of the cable rod. A cable connector to which a cable terminal from the borehole entrance is coupled at one end, a measurement cable coupled to a position away from the center of the end surface of the other end of the cable connector, and communicated with a measurement device at the tip of the borehole; A cable housing tube attached to the tip of the cable connector, housing the measuring device and the measurement cable, and having an outer peripheral portion fixed to the ground, and the cable connector side of the cable housing tube; The cable is attached to an end face to be screwed and is rotated by a rotational movement when loosening the screw connection with the cable connector. A cable cutter for cutting the measurement cable coupled to a position away from the center of the end face of the connector; and the inside of the cable, the cable rod, the cable connector, the measurement cable, and the cable storage tube; And a casing for protecting the housing.

  The present invention is also a system for measuring seismic waves in an underground boring hole, and is attached to a cable rod inserted into the boring hole together with a cable along an outer peripheral portion, and attached to a tip of the boring hole of the cable rod. A cable connector to which one end of the cable connector from the boring hole inlet is coupled, and a measurement that is coupled to a position away from the center of the end surface of the other end of the cable connector and communicates with the measuring device at the tip of the boring hole. A cable, a cable housing tube attached to the tip of the cable connector, housing the measuring device and the measurement cable, and having an outer peripheral portion fixed to the ground; and the cable connector of the cable housing tube It is attached to the end face that is screwed to the side, and the rotational movement when loosening the screw connection with the cable connector A cable cutter that cuts the measurement cable coupled to a position away from the center of the end face of the cable connector; and the cable, the cable rod, the cable connector, the measurement cable, and the cable storage tube are accommodated therein, and the boring A casing that protects a hole wall; and a casing sealing plug that includes the cable and the through hole for the cable rod and that is attached to an inlet side of the casing and blocks ejected matter from the casing. And

  The cable rod can be rotated at the boring hole inlet, and the cutting blade of the cable cutter has a hollow circular or polygonal shape whose diameter is ½ or less of the diameter of the cable storage tube. And passing the apparatus cable coupled to a position away from the center of the end face of the other end of the cable connector through the hollow portion, and the center is eccentric to a position shifted from the center of the end face of the cable housing tube. It is characterized by being mounted.

  Further, the present invention provides a cutting blade mounted on the end surface of the cable storage tube by measuring the seismic wave in the seismic wave measurement system and then loosening the screwing between the cable storage tube and the cable connector by rotating the cable rod. Rotate and disconnect the cable for the device that is eccentrically coupled to the cable connector and fixed, and place the device cable and the measuring device in the boring hole, and boring the cable, the cable rod, and the connector It collects out of the hole.

  Further, the present invention provides the above seismic wave measurement system, in which the casing sealing plug is attached to the inlet side of the casing and the seismic wave is measured, and then the cable rod is rotated to loosen the screw connection between the cable storage tube and the cable connector. The cutting blade mounted on the end face of the cable storage tube is rotated, the device cable that is eccentrically coupled to the cable connector and is fixed and cut is fixed, and the device cable and the measuring device are placed in the borehole. It is detained, and the cable, the cable rod, and the connector are collected outside the boring hole.

According to the present invention, it has become possible to measure the ground speed of a crushing zone or the like that has been violently collapsed, which is conventionally impossible to perform speed logging.
In addition, it is possible to check ground information by closing underground water, gas, oil, and the like that erupt from the ground, returning the deep underground to a natural state.

The present invention sets a speed logging instrument on a non-self-supported hole ground, removes the casing, detains the instrument with ground collapse, measures the ground speed, cuts the cable connected to the instrument, This is a system that leaves the inside of the hole and collects the insertion rod and measurement cable.
By efficiently disposing this measuring instrument, it becomes possible to perform velocity logging of non-independent hole ground, which has been extremely difficult to measure in the past. In addition, by using the casing sealing plug of the present invention, a plurality of inserts such as an in-hole measuring instrument insertion rod, a measurement cable, and in some cases, an injection hose, are closed together to stop the ejected matter from the ground. Thus, the ground can be returned to a natural state and various ground information of the ground can be measured.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram of a cable cutter employed in the seismic wave measurement system of the present invention, FIG. 2 is an explanatory diagram for explaining a measurement method by the seismic wave measurement system, FIG. 3 is a schematic diagram of a casing sealing plug, and FIG. It is explanatory drawing explaining the obstruction | occlusion condition by a casing sealing stopper.

  As shown in FIG. 1, the seismic wave measuring system 1 of the present invention includes a cable rod 3 inserted into a boring hole 6 together with a cable 4 along the outer periphery, and a terminal of the cable 4 from the entrance of the boring hole 6 at one end thereof. The cable connector 7 to be coupled, the measurement cable 9 communicating with the measuring device 5 at the tip of the boring hole 6, the cable storage tube 8 attached to the tip of the cable connector 7, and the end surface of the cable storage tube 8 are attached. , A cable cutter 10 for cutting the measurement cable 9, a casing 2 for storing the cable 4, the cable rod 3, the cable connector 7, the measurement cable 9 and the cable storage pipe 8 inside, and protecting the boring hole wall; A casing sealing plug 12 which is mounted on the inlet side and blocks the ejected matter from the inside of the casing 2. It is made.

The cable connector 7 is attached to the tip of the boring hole 6 of the cable rod 3, and the end of the cable 4 from the inlet of the boring hole 6 is coupled to one end thereof.
The measurement cable 9 is coupled to a position away from the center of the end surface of the other end of the cable connector 7 and communicates with the measurement device 5 at the tip of the boring hole 6.
The cable storage tube 8 is attached to the distal end portion of the cable connector 7, and stores the measuring device 5 and the measurement cable 9, and the outer peripheral portion is fixed to the ground.

The cable cutter 10 is attached to the cable housing tube 8 and the end surface screwed with the cable connector 7 side of the cable housing tube 8, and is attached at a position away from the center of the end surface of the cable connector 7 as shown in FIG. Thus, the measurement cable 9 that is also mounted at a position away from the center is cut by a rotational movement when the screw connection with the cable connector 7 is loosened.
The casing 2 accommodates the cable 4, the cable rod 3, the cable connector 7, the measurement cable 9, and the cable storage tube 8 inside, and protects the boring hole wall.
The casing sealing plug 12 includes through holes for the cable 4 and the cable rod 3 and is attached to the inlet side of the casing 2 to block the ejected matter from the inside of the casing 2.

The cable rod 3 can be rotated at the entrance of the boring hole 6.
The cutting blade of the cable cutter 10 has a hollow circular or polygonal shape whose diameter is ½ or less of the diameter of the cable storage tube 8, and the end of the other end of the cable connector 7 is formed in the hollow portion. The device cable coupled to a position away from the center is passed through, and the center is eccentrically mounted at a position shifted from the center of the end face of the cable housing tube 8.

Next, an operation method of the seismic wave measurement system 1 will be described.
After measuring the seismic wave with the seismic wave measuring system 1, the cable rod 3 is rotated to loosen the screw connection between the cable housing tube 8 and the cable connector 7, and the cutting blade of the cable cutter 10 attached to the end surface of the cable housing tube 8. , The measurement cable 9 that is eccentrically coupled to the cable connector 7 and cut in a fixed state is cut, and the measurement cable 9 and the measurement device 5 are placed in the boring hole 6. The cable 4, the cable rod 3 and the cable connector 7 are collected outside the boring hole 6.

FIG. 2 shows an outline of the cutting method of the measurement cable 9 of the seismic wave measurement system 1.
As shown in FIG. 2, in order to measure seismic waves, the casing 2 is driven into the ground that tends to collapse, and the cable rod 3, the cable 4, and the measuring device 5 are inserted into the casing 2.
After inserting the measuring device 5 to the target position, the measuring device 5 is buried in the collapsed ground by pulling out the casing 2 to the ground. Seismic wave measurement is performed with the measuring device 5 buried in a collapsed ground.
After the end of the seismic wave measurement, the cable rod 3 is rotated and the measurement cable 9 is cut and separated by the cable cutter 10, and the measurement device 5 is left in the collapsed ground, and the cable rod 3 and the cable 4 are collected on the ground.

FIG. 3 shows an outline of the casing sealing plug 12. In the ground from which groundwater or the like springs as shown in FIG. 3A, the ground condition cannot be measured due to the ejection of groundwater or the like.
The casing sealing plug 12 of the present invention is attached to the ground-side tip of the casing 2 when groundwater or the like is expected, and the casing sealing plug 12 has holes for passing the cable rod 3 and the cable 4. It has been opened.
By mounting the casing sealing plug 12, the ejection of groundwater or the like to the ground can be stopped, and the seismic wave can be measured.

FIG. 4 is an explanatory diagram for explaining the closed state by the casing sealing plug 12. In the past, the portions indicated by the oblique lines in (a) and (b) are closed. It was not possible to block between the inserts.
The casing sealing plug 12 according to the present invention can be completely closed even when there are a plurality of inserts as shown in (c).

Conventionally, when measuring seismic waves on a fragile ground, when a measuring instrument with a cable cannot be pulled out, the cable is pulled and forcibly cut, so even if the entire cable can be recovered, the cable with excessive force applied cannot be used. There were many.
In the seismic wave measurement system of the present invention, it is possible to measure the next section because almost the entire amount of the cable can be recovered intact on the premise that the cable is left uncut in advance.
In the seismic wave measurement system of the present invention, the measuring instrument is left in the ground, but leaving the measuring instrument and the like is not a problem, and a great effect is obtained that enables direct measurement of the formation, which has been considered impossible in the past.

It is the schematic of the cable cutter employ | adopted for the seismic wave measurement system of this invention. It is explanatory drawing explaining the measuring method by the seismic wave measuring system of this invention. It is a schematic diagram of the casing sealing stopper of the present invention. It is explanatory drawing explaining the obstruction | occlusion condition by the casing sealing stopper of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seismic wave measurement system 2 Casing 3 Cable rod 4 Cable 5 Measuring device 6 Boring hole 7 Cable connector 8 Cable storage tube 9 Measurement cable 8 Cable storage tube 10 Cable cutter 12 Casing sealing plug

Claims (6)

A system for measuring seismic waves in underground boreholes,
A cable rod to be inserted into the boring hole together with the cable along the outer periphery,
A cable connector attached to a tip of the boring hole of the cable rod, and a cable terminal from the boring hole inlet coupled to one end thereof;
A measurement cable coupled to a position away from the center of the end face of the other end of the cable connector and communicated with a measuring device at the tip of the borehole;
A cable storage tube attached to the tip of the cable connector, storing the measurement device and the measurement cable, and having an outer peripheral portion fixed to the ground;
The measurement cable is attached to an end surface of the cable housing tube that is screwed with the cable connector side, and is coupled to a position away from the center of the end surface of the cable connector by a rotational movement when loosening the screw connection with the cable connector. Cutting the cable cutter,
A casing for storing the cable, the cable rod, the cable connector, the measurement cable, and the cable storage tube inside, and protecting the boring hole wall;
Seismic wave measurement system characterized by including. A system for measuring seismic waves in underground boreholes,
A cable rod to be inserted into the boring hole together with the cable along the outer periphery,
A cable connector attached to a tip of the boring hole of the cable rod, and a cable terminal from the boring hole inlet coupled to one end thereof;
A measurement cable coupled to a position away from the center of the end face of the other end of the cable connector and communicated with a measuring device at the tip of the borehole;
A cable storage tube attached to the tip of the cable connector, storing the measurement device and the measurement cable, and having an outer peripheral portion fixed to the ground;
The measurement cable is attached to an end surface of the cable housing tube that is screwed with the cable connector side, and is coupled to a position away from the center of the end surface of the cable connector by a rotational movement when loosening the screw connection with the cable connector. Cutting the cable cutter,
A casing for storing the cable, the cable rod, the cable connector, the measurement cable, and the cable storage tube inside, and protecting the boring hole wall;
A casing sealing plug that includes the cable and the through hole for the cable rod, and is attached to the inlet side of the casing to block the ejected matter from the casing;
Seismic wave measurement system characterized by including.   The seismic wave measurement system according to claim 1 or 2, wherein the cable rod can be rotated at an entrance of a boring hole.   The cutting blade of the cable cutter has a hollow circular or polygonal shape whose diameter is ½ or less of the diameter of the cable storage tube, and is separated from the center of the end face of the other end of the cable connector in the hollow portion. 3. The apparatus cable according to claim 1, wherein the device cable coupled at a predetermined position is penetrated, and a center thereof is eccentrically mounted at a position shifted from a center of an end face of the cable storage tube. Seismic wave measurement system. After measuring the seismic wave in the seismic wave measuring system according to claim 1 or 2,
By rotating the cable rod, the threaded connection between the cable housing tube and the cable connector is loosened, the cutting blade mounted on the end surface of the cable housing tube is rotated, and the cable connector is eccentrically coupled to the cable connector and is in a fixed state. A method for measuring seismic waves, comprising cutting a device cable, placing the device cable and the measuring device in a borehole, and collecting the cable, the cable rod, and the connector out of the borehole. In the seismic wave measurement system according to claim 1 or 2,
After measuring the seismic wave by installing a casing sealing plug on the inlet side of the casing,
By rotating the cable rod, the threaded connection between the cable housing tube and the cable connector is loosened, the cutting blade mounted on the end surface of the cable housing tube is rotated, and the cable connector is eccentrically coupled to the cable connector and is in a fixed state. A method for measuring seismic waves, comprising cutting a device cable, placing the device cable and the measuring device in a borehole, and collecting the cable, the cable rod, and the connector out of the borehole.

Images