CN117006966A - Multidirectional displacement detection device for non-excavated rock mass in front of segmented tunnel face - Google Patents

Abstract

The invention relates to the technical field of tunnel construction monitoring, and specifically to a segmented multi-directional displacement detection device of unexcavated rock mass in front of the tunnel face, including: a segmented multi-point laser displacement meter, which is buried in front of the tunnel face. In the unexcavated rock mass, it is used to measure the unexcavated rock mass in front of the tunnel face to obtain the extrusion deformation value of the rock mass and the laser displacement signal; the laser displacement receiver is fixed on the tunnel ground. It is used to receive the laser displacement signal sent by the segmented multi-point laser displacement meter, and obtain the rock mass displacement data based on the laser displacement signal; the rock mass displacement data includes the horizontal displacement of the rock mass and the settlement displacement of the vault. This solution uses laser point changes buried in deep rock mass to obtain horizontal and vault settlement deformations, and obtains the extrusion deformation through spring measuring rods, thus realizing a measuring instrument to measure the three-dimensional deformation of the rock mass, reducing repeated drilling, Repositioning eliminates human error, is highly practical and easy to operate.

Description

Multi-directional displacement detection device of unexcavated rock mass in front of segmented tunnel face

Technical field

The invention relates to the technical field of tunnel construction monitoring, and in particular to a segmented multi-directional displacement detection device of unexcavated rock mass in front of a tunnel face.

Background technique

As tunnel projects face more and more complex geological and environmental conditions, the New Idea method, which focuses on advanced support and reinforcement measures to reduce the deformation of the surrounding rock, gradually replaces the New Austrian method and becomes the most commonly used and effective construction method under special geological conditions. construction method. The new method emphasizes the importance of strengthening the tunnel face and the core surrounding rock in front of the tunnel face, and believes that the instability of the working face and the core surrounding rock in front is the induced cause of tunnel collapse and instability. As shown in Figure 1, with the tunnel face as the boundary, the tunnel surrounding rock deformation can be spatially divided into three parts: the advanced deformation in front of the tunnel face, the extrusion deformation of the tunnel face, and the deformation behind the tunnel face, and The three parts of deformation occur simultaneously.

Among them, the deformation of the tunnel face and the deformation behind the tunnel face account for about 80% of the total deformation, and are relatively easy to observe and detect, and are not likely to cause sudden tunnel disasters, while the deformation that occurs in front of the tunnel face never The direction can be divided into horizontal deformation and vertical settlement. Horizontal deformation can be regarded as the extrusion deformation of the surrounding rock, which is usually roughly measured by the deformation of the tunnel face. Vertical settlement is the advanced settlement of the rock mass in front of the tunnel face. There are two main measurement standards, one is the range of advanced settlement, and the other is the amount of advanced settlement. The range of advanced settlement continues with the excavation of the tunnel face. Moving forward, usually the maximum deformation occurs at the tunnel face. Once the deformation in front of the tunnel face, especially premature settlement, occurs, it will easily cause the tunnel to collapse quickly, posing a huge threat to the tunnel support and the personal safety of the construction personnel. Based on this, it is of great practical significance to develop a device and method that can be used in Xinyi tunnel excavation to detect the horizontal and vertical displacement of the unexcavated rock mass in front of the tunnel face, and can further improve tunnel construction. Safety and quality, ensuring the safety of tunnels and construction personnel.

At present, sliding micrometers and incremental extensometers are usually used in the existing technology. Sliding micrometers and incremental extensometers have good effects on measuring extrusion deformation and vault settlement, but the procurement cost is too high. It is difficult to apply it on a large scale in domestic tunnel projects. There are few domestic studies on measuring devices for the deformation of unexcavated rock mass in front of the tunnel face, and there is no measuring device with simple structure, accurate measurement and high practicability. Chinese Patent Publication No. CN209495623U discloses a multi-point displacement measurement and reading device. Although this device can effectively measure the displacement of rock and soil masses, the entire device has a complex structure, an extremely complicated assembly process, and higher requirements for burial. The operation is complicated and difficult to master. In addition, when rock blasting, it is difficult to ensure that the test components at the test point are not damaged; Chinese Patent Publication No. 209230544U discloses a monitoring device for tunnel tunnel face extrusion deformation, which is simple to operate. , easy to use, but because the laser scanner is a precision instrument, it is greatly affected by disturbances from tunnel construction and blasting, and it cannot measure the settlement of the vault in front of the tunnel. It is difficult to ensure measurement accuracy and has few applications.

In view of this, it is necessary to develop a remote sensing multi-directional displacement detection device of unexcavated rock mass in tunnels that is highly practical and easy to operate, in order to quickly and accurately measure the deformation of unexcavated rock mass in tunnels in multiple directions, and in On this basis, a set of effective testing methods is designed to further enrich the monitoring methods and technologies for the rock mass in front of the tunnel tunnel face.

Contents of the invention

In view of the shortcomings of the existing technology, the present invention proposes a segmented multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face, so as to be able to simultaneously measure multiple directions of the unexcavated rock mass in front of the tunnel face. deformation and easy operation.

The technical solution adopted by the present invention is a segmented multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face.

In the first possible way, a segmented multi-directional displacement detection device of unexcavated rock mass in front of the tunnel face includes:

The segmented multi-point laser displacement meter is buried in the unexcavated rock mass in front of the tunnel face. The segmented multi-point laser displacement meter is used to measure the unexcavated rock mass in front of the tunnel face and obtain the rock mass. Extrusion deformation value and laser displacement signal;

The laser displacement receiver is fixed on the tunnel floor. The laser displacement receiver is used to receive the laser displacement signal sent by the segmented multi-point laser displacement instrument and obtain the rock mass displacement data based on the laser displacement signal; the rock mass displacement data includes the rock mass level. displacement and vault settlement displacement.

Combined with the first implementable manner, the second implementable manner includes: a grouting pipe, which is fixed above the segmented multi-point laser displacement instrument through a slot.

Combined with the first realizable way, in the third realizable way, the segmented multi-point laser displacement instrument includes:

The fixed detection unit is buried in the unexcavated rock mass in front of the tunnel face. The fixed detection unit is used to measure the unexcavated rock mass and obtain the extrusion deformation value of the rock mass and multiple initial laser signals;

The detachable unit is communicatively connected with the fixed detection unit; the detachable unit is used to receive multiple initial laser signals and obtain laser displacement signals based on the multiple initial laser signals.

Combined with the third implementable manner, in the fourth implementable manner, the fixed detection unit includes:

Several laser channels are equipped with several laser repeaters inside, and the other end of each laser channel is connected to one end of the spring measuring rod;

Spring measuring rod, the other end is connected to one end of the laser transmitter;

Laser transmitter, the other end is connected to the anchor head;

The displacement sensor is fixed at the connection end of the laser channel and the spring measuring rod.

Combined with the fourth realizable method, in the fifth realizable method, the unexcavated rock mass in front of the tunnel face is the area to be blasted, and the area to be blasted is divided into multiple sub-areas to be blasted according to the order of blasting; The fixed detection unit traverses each sub-area to be blasted; each laser repeater in the fixed detection unit is arranged at the dividing surface between each sub-area to be blasted.

Combined with the fourth implementable manner, in the sixth implementable manner, the number of laser repeaters in each laser channel is different, and each laser repeater is provided with a photoelectric sensor.

Combined with the fourth implementable manner, in the seventh implementable manner, the fixed detection unit also includes:

The laser repeater protective tube is set at the periphery of the laser channel corresponding to the laser repeater. The laser repeater protective tube is used to protect the laser repeater;

The sealing head is arranged between the laser channel and the spring measuring rod. The sealing head is used to seal and protect the entrance of the laser channel;

The stabilizing plate covers all laser channels and is used to fix the laser channels.

Combined with the fourth implementable manner, in the eighth implementable manner, the detachable unit includes:

Laser displacement refractor, set on one side of the laser clearer;

Laser clear instrument, the other side is connected to the laser channel.

Combined with the first realizable way, in the ninth realizable way, the laser displacement receiver includes:

Laser displacement receiving light screen, used to receive the laser displacement signal refracted by the laser displacement refractor;

Calibration laser, used for laser calibration;

Laser signal converter is used to convert laser displacement signals into electrical signals.

Combined with the first realizable way, the tenth realizable way includes:

The console is connected to the laser displacement receiver and the segmented multi-point laser displacement instrument respectively. The console is used to receive the rock mass displacement data and the rock mass extrusion deformation value, and conduct the analysis on the rock mass displacement data and the rock mass extrusion deformation value. Real-time display and storage.

It can be seen from the above technical solutions that the beneficial technical effects of the present invention are as follows:

1. This solution uses laser positioning embedded in deep rock mass, obtains horizontal and vault settlement deformations through laser point changes, and obtains extrusion deformation through spring measuring rods, thereby achieving rock mass measurement in one measuring instrument. Three-dimensional deformation measurement, thereby reducing human errors caused by repeated drilling and repositioning, is highly practical, simple to operate, and accurate in measurement, making it more convenient.

2. This solution sets multiple laser repeaters at intervals in multiple laser channels to achieve segmented measurement, with simple structure and accurate measurement. When there is a problem with the laser repeater at a certain section or point, the actual displacement change can still be obtained from the data at other points, thus avoiding damage to the measuring instrument and the measurement impact of blasting to the greatest extent, and ensuring the continuity of measurement data. It can also monitor the rock mass deformation data in real time when the tunnel face is continuously excavated.

3. This device has a simple structure, is easy to bury, is simple to operate and easy to master, and the device can be reused, so the cost of testing is lower. In addition, the overall hardness of this device is relatively large, it is not easily affected by changes in the external environment, and the data measurement accuracy is high.

Description of the drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the specific embodiments or the prior art. Throughout the drawings, similar elements or portions are generally identified by similar reference numerals. In the drawings, elements or parts are not necessarily drawn to actual scale.

Figure 1 is a schematic diagram of the deformation of a tunnel constructed using the novel method in the prior art provided by this embodiment;

Figure 2 is a schematic diagram of the installation of a multi-directional displacement detection device for unexcavated rock mass in front of the segmented tunnel tunnel face provided in this embodiment;

Figure 3 is a schematic structural diagram of a segmented multi-point laser displacement meter provided in this embodiment;

Figure 4 is a cross-sectional schematic diagram of a segmented multi-point laser displacement meter provided in this embodiment;

Figure 5 is a schematic diagram of the multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face of the first segmented tunnel blasting provided in this embodiment;

Figure 6 is a schematic diagram of the multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face of the second segmented tunnel blasting provided by this embodiment;

Figure 7 is a schematic diagram of the multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face of the third segmented tunnel blasting provided by this embodiment;

Figure 8 is a schematic diagram of the multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face of the fourth segmented tunnel blasting provided in this embodiment;

Reference signs:

1-Segmented multi-point laser displacement meter, 11-laser channel, 12-laser repeater, 13-displacement sensor, 14-spring rod, 15-laser emitter, 16-anchor head, 17-stabilizing plate, 18-laser repeater protective tube, 19-sealing head, 2-laser displacement receiver, 20-laser clear instrument, 21-laser displacement refractor, 22-shield, 23-sealing tube, 24-anchoring base , 3-console, 4-grouting pipe, 5-card slot.

Detailed ways

The embodiments of the technical solution of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present invention more clearly, and are therefore only examples and cannot be used to limit the scope of the present invention.

It should be noted that, unless otherwise stated, the technical terms or scientific terms used in this application should have the usual meanings understood by those skilled in the art to which this invention belongs. The terms "first", "second", etc. in the description and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that data so used may be interchanged under appropriate circumstances to facilitate the implementation of the embodiments of the disclosure described herein. Furthermore, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. Unless otherwise stated, the term "plurality" means two or more. In the embodiment of the present disclosure, the character "/" indicates that the preceding and following objects are in an "or" relationship. For example, A/B means: A or B. The term "and/or" is an association relationship describing objects, indicating that three relationships can exist. For example, A and/or B means: A or B, or A and B. The term "correspondence" can refer to an association relationship or a binding relationship. The correspondence between A and B refers to an association relationship or a binding relationship between A and B.

As shown in Figure 2, this embodiment provides a segmented multi-directional displacement detection device for the unexcavated rock mass in front of the tunnel face, including:

The segmented multi-point laser displacement meter 1 is buried in the unexcavated rock mass in front of the tunnel face. The segmented multi-point laser displacement meter is used to measure the unexcavated rock mass in front of the tunnel face and obtain the rock mass. Volume extrusion deformation value and laser displacement signal;

Laser displacement receiver 2 is fixed on the tunnel floor. The laser displacement receiver is used to receive the laser displacement signal sent by the segmented multi-point laser displacement instrument and obtain the rock mass displacement data based on the laser displacement signal. The rock mass displacement data includes the rock mass. Horizontal displacement and vault settlement displacement.

Optionally, the multi-directional displacement detection device of the unexcavated rock mass in front of the segmented tunnel face includes: a grouting pipe 4, which is fixed above the segmented multi-point laser displacement instrument 1 through a slot 5.

Optionally, a plurality of slots are provided at intervals between the grouting pipe and the segmented multi-point laser displacement meter, and the grouting pipe is fixed above the segmented multi-point laser displacement meter through each slot. The cement slurry is filled into the gap between the segmented multi-point laser displacement meter and the rotary hole through the grouting pipe, so that the segmented laser displacement meter is firmly fixed in the unexcavated rock mass in front of the tunnel face.

Optionally, the segmented multi-point laser displacement instrument includes: a fixed detection unit, which is buried in the unexcavated rock mass in front of the tunnel face. The fixed detection unit is used to measure the unexcavated rock mass and obtain the rock mass extrusion. The deformation value and multiple initial laser signals are output; the detachable unit is communicated with the fixed detection unit; the detachable unit is used to receive multiple initial laser signals and obtain laser displacement signals based on the multiple initial laser signals.

As shown in FIG. 3 , optionally, the fixed detection unit includes: several laser channels 11 , each of which is provided with several laser repeaters 12 , and the other end of each laser channel 11 is connected to one end of the spring measuring rod 14 ; The other end of the measuring rod 14 is connected to one end of the laser transmitter 15; the other end of the laser transmitter 15 is connected to the anchor head 16; the displacement sensor 13 is fixed at the connecting end of the laser channel 11 and the spring measuring rod 14.

Optionally, the unexcavated rock mass in front of the tunnel face is the area to be blasted, and the area to be blasted is divided into multiple sub-areas to be blasted according to the order of blasting; the fixed detection unit traverses each sub-area to be blasted; fixed detection Each laser repeater in the unit is arranged at the dividing plane between the sub-areas to be blasted.

By arranging laser repeaters on the dividing surfaces between the sub-areas to be blasted, segmented measurement is achieved. In this way, when there is a problem with the laser repeater in a certain section or a certain point, it can still pass through other points. The actual displacement changes can be obtained from the position data, which can avoid the damage and measurement impact of blasting on the measuring instruments to the greatest extent, ensure the continuity of the measurement data, and can also monitor the rock mass deformation data in real time when the tunnel face is continuously excavated.

Optionally, the number of laser repeaters in each laser channel is different, and each laser repeater is provided with a photoelectric sensor. By setting up multiple laser channels and setting up different numbers of laser repeaters in the laser channel, using multiple laser transmission paths to transmit the initial laser signal can not only prevent damage to a certain laser channel and cause the device to become unusable, but also Improve error tolerance, thereby improving measurement accuracy.

In some embodiments, three laser repeaters are arranged in the first laser channel, two laser repeaters are arranged in the second laser channel, and one laser repeater is arranged in the third laser channel. Each laser repeater is equipped with a photoelectric sensor. After receiving the initial laser signal, the photoelectric sensor uses the coordinates of the light screen hit by the initial laser signal as the coordinates of the rock mass measuring point, and obtains the corresponding light screen from the coordinates of the rock mass measuring point. The initial laser signal is emitted from the position to the laser repeater or laser displacement refractor at the back end.

Optionally, the fixed detection unit also includes: a laser repeater protective tube 18, which is arranged on the periphery of the laser channel 11 corresponding to the laser repeater 12. The laser repeater protective tube 18 is used to protect the laser repeater 12; The sealing head 19 is arranged between the laser channel 11 and the spring measuring rod 14. The sealing head 19 is used to seal and protect the entrance of the laser channel 11; the stabilizing plate 17 wraps all the laser channels 11 and the stabilizing plate 17 is used to seal the laser. Channel 11 is fixed.

In some embodiments, the fixed detection unit is placed and fixed in the drilled hole after the drilling is completed. As shown in FIG. 4 , a grouting pipe 5 is fixed above the fixed detection unit of the segmented multi-point laser displacement instrument 1 through a slot 2 . There are three detachable laser channels 11 evenly distributed inside the fixed detection unit, and a stabilizing plate is used between the laser channels to maintain the stability of the channels and relative displacement. Laser repeaters are installed inside and outside each laser channel. The laser channel corresponding to the position of the laser repeater is wrapped with a laser repeater protective tube, and the laser repeater protective tube can further ensure the stability of the channel itself and protect the laser repeater from damage. The frontmost layer of the laser channel is equipped with a sealing head, which is used to seal and protect the entrance of the laser channel to prevent high-temperature water vapor from appearing inside the drill hole and affecting the laser channel. After the spring measuring rod is connected to the anchor head, the displacement sensor can directly and accurately measure the deformation of the spring measuring rod, thereby obtaining the extrusion deformation of the rock mass in front of the tunnel face.

Optionally, the detachable unit includes: a laser displacement refractor 21, which is arranged on one side of the laser clearer 20; the other side of the laser clearer 20 is connected to the laser channel 11.

Optionally, the detachable unit also includes: a shield 22 arranged around the laser displacement refractor 21 and the laser clearer 20; and an anchoring base 24 for fixing the laser clearer 20.

Optionally, the detachable unit also includes a sealing tube 23. The sealing tube 23 and the shield 22 completely seal and protect the laser displacement refractor 21 and the laser clearer 20.

In some embodiments, each component in the detachable unit is detachable, and the detachable unit is directly connected at the tunnel face to a fixed detection unit embedded in the unexcavated rock mass in front of the tunnel tunnel face. Or, the detachable unit can be moved away from the tunnel face through the movable base, and then moved to a safe distance for laser zeroing and alignment with the laser repeater in the fixed detection unit to achieve remote connection, thus avoiding tunnel face blasting to the greatest extent. Influence.

Optionally, the laser displacement receiver includes: a laser displacement receiving light screen, used to receive the laser displacement signal refracted by the laser displacement refractor; a calibration laser, used for laser calibration; a laser signal converter, used to convert the laser displacement signal into Electrical signal; the electrical signal converted from the laser displacement signal is the rock mass measuring point coordinate signal.

As shown in Figure 2, the multi-directional displacement detection device of the unexcavated rock mass in front of the segmented tunnel face includes: a console 3, which is electrically connected to the laser displacement receiver 2. The console is also connected to a segmented multi-point laser displacement instrument. The console is used to receive rock mass displacement data and rock mass extrusion deformation values, and display and store the rock mass displacement data and rock mass extrusion deformation values in real time.

As shown in Figure 2, the laser displacement receiver 2 is anchored on the tunnel floor through a fixed bracket 21, and is connected to the console 3 through an integrated line.

Optionally, the segmented multi-point laser displacement meter transmits the rock mass extrusion deformation value directly to the console, or the segmented multi-point laser displacement meter transmits the rock mass extrusion deformation value to the control panel through a laser displacement receiver. tower.

Optionally, the console includes: a PC display screen, used to display the rock mass extrusion deformation value and rock mass displacement data of the rock mass in front of the tunnel face in real time; a power switch, used to control the connection of the power supply; a light screen adjustment knob , used to adjust the displacement point on the PC display screen; the information recorder, used to store the rock mass extrusion deformation value and rock mass displacement data of the rock mass in front of the tunnel face.

In some embodiments, after the console obtains the multi-directional displacement of the unexcavated rock mass in front of the tunnel face based on the received rock mass displacement data and rock mass extrusion deformation values, the console displays the multi-directional displacement of the unexcavated rock mass in front of the tunnel face through the PC display screen. The multi-directional displacement of the unexcavated rock mass in front of the tunnel face is displayed in real time, and the multi-directional displacement of the unexcavated rock mass in front of the tunnel face is stored through the information recorder. Use the light screen adjustment knob to zero out or make other adjustments to the displacement point on the PC display screen.

Optionally, obtaining the extrusion displacement of the rock mass in front of the tunnel face includes: obtaining the initial rock mass extrusion deformation value and the current rock mass extrusion deformation value of the displacement sensor; and averaging the current rock mass extrusion deformation value. Subtract the average value of the initial rock mass extrusion deformation values to obtain the extrusion displacement of the rock mass in front of the tunnel face.

Optionally, the multi-directional displacement includes the horizontal displacement of the rock mass in the X direction, the vault settlement displacement in the Y direction, and the extrusion displacement of the rock mass in the Z direction.

As shown in Figure 5 , in some embodiments, the area to be blasted in the rock mass in front of the tunnel face is divided into three sub-areas to be blasted by dividing planes A, B, C, and D: area a, area b, and area c. , blasting area a, area b and area c in sequence during blasting. Before blasting occurs, segmented surface A is the current tunnel surface, the detachable unit of the segmented multi-point laser displacement instrument is arranged in front of A, and the fixed detection unit of the segmented multi-point laser displacement instrument traverses areas a and b. area and c area. Different numbers of laser repeaters are arranged in the three laser channels of the segmented multi-point laser displacement instrument, and the positions of each laser repeater are located at each segmentation plane.

In some embodiments, the first laser channel is equipped with three laser repeaters, which are located on the dividing planes B, C, and D respectively. The second laser channel is equipped with two laser repeaters, which are located on the dividing planes C and D respectively. The third laser channel is equipped with a laser repeater, located on the dividing plane D.

In some embodiments, as shown in Figure 5, before zone a is blasted, the displacement sensor corresponding to each laser channel transmits the measured rock mass extrusion deformation values d1, d2 and d3 of the spring rod to the console. The laser emitters corresponding to the three laser channels in the segmented multi-point laser displacement instrument respectively send out initial laser signals, which pass through the laser repeaters in each laser channel and reach the laser displacement refractor at A for focusing. For example, the initial laser signal of the first laser channel is transmitted through the laser transmission lines of C1c, C1b and C1a, reaches the laser displacement refractor, and the first laser signal C1 is obtained; the initial laser signal of the second laser channel is transmitted through the laser transmission lines of C2c, C2b. The laser transmission line is transmitted, and reaches the laser displacement refractor, and the second laser signal C2 is obtained; the initial laser signal of the third laser channel is transmitted through the laser transmission line of C3c, and reaches the laser displacement refractor, and the first laser signal C3 is obtained. . The laser displacement refractor focuses the laser signals C1, C2, and C3 emitted by the three laser channels to obtain the final laser displacement signal, and emits the initial laser signal from the corresponding position of the laser displacement signal to the laser displacement receiving light screen, and receives it through the laser displacement The photoelectric sensor in the light screen obtains the displacement electrical signal, which is the initial rock mass measuring point coordinate O. The rock mass measuring point coordinates include the horizontal coordinates in the X direction and the vault settlement coordinates in the Y direction.

As shown in Figure 6, after the blasting in area a is completed, the current tunnel surface here is the split surface B, and the rock mass measuring points are displaced. The displacement sensor corresponding to each laser channel transmits the measured rock mass extrusion deformation values d1`, d2` and d3` of the spring measuring rod to the console. The initial laser signal in the first laser channel is transmitted to the laser displacement refractor through the laser transmission lines C1c`, C1b`, and C1a` to obtain the laser signal C1`. The initial laser signal in the second laser channel is transmitted through the laser transmission lines C2c` and C2b` to obtain the laser signal C2` to the laser displacement refractor. Get laser signal. The initial laser signal in the third laser channel is transmitted to the laser displacement refractor via the laser transmission line C3c` to obtain the laser signal C3`. The laser displacement refractor focuses the laser signals C1`, C2` and C3` to obtain the current laser displacement signal, and obtains the rock mass measurement point coordinates O` after the blasting in zone a through the laser displacement receiving light screen.

As shown in Figure 7, after the blasting in area b is completed, the current tunnel face here is the split plane C, and the rock mass measuring points have been displaced. The displacement sensor corresponding to each laser channel transmits the measured rock mass extrusion deformation values d1``, d2`` and d3`` of the spring measuring rod to the console. The initial laser signal in the first laser channel transmits the laser signal C1`` to the laser displacement refractor via the laser transmission lines C1c`` and C1b``. The initial laser signal in the second laser channel transmits the laser signal C2`` to the laser displacement refractor via the laser transmission lines C2c`` and C2b``. The initial laser signal in the third laser channel transmits the laser signal C3 to the laser displacement refractor via the laser transmission line C3c. The laser displacement refractor focuses the laser signals C1``, C2`` and C3`` to obtain the current laser displacement signal, and obtains the rock mass measurement point coordinates O`` after the blasting in area b through the laser displacement receiving light screen.

As shown in Figure 8, after the blasting in area c is completed, the current tunnel face here is the split plane E, and the rock mass measuring points have been displaced. The displacement sensor corresponding to each laser channel transmits the measured rock mass extrusion deformation values d1````, d2```` and d3```` of the spring measuring rod to the console. The initial laser signal in the first laser channel transmits the laser signal C1``` to the laser displacement refractor via the laser transmission line C1c```. The initial laser signal in the second laser channel transmits the laser signal C2``` to the laser displacement refractor via the laser transmission line C2c```. The initial laser signal in the third laser channel transmits the laser signal C3``` to the laser displacement refractor via the laser transmission line C3c```. The laser displacement refractor focuses the laser signals C1```, C2``` and C3``` to obtain the current laser displacement signal, and obtains the rock mass measurement point coordinates O after the blasting in area c through the laser displacement receiving light screen. ```.

Optionally, obtain the horizontal displacement of the rock mass in front of the tunnel face and the vault settlement displacement, including: obtaining the initial rock mass measuring point coordinates and the rock mass measuring point coordinates after blasting, and converting the blasted rock mass measuring point The coordinates are subtracted from the initial rock mass measuring point coordinates to obtain the displacement change of the rock mass measuring point. The displacement change includes the horizontal displacement in the X direction and the vault settlement displacement in the Y direction, which is the rock mass in front of the tunnel face. Horizontal displacement and vault settlement displacement.

Optionally, the laser displacement receiving light screen adjusts the initial rock mass measuring point coordinates to (0, 0), then after blasting, the rock mass measuring point coordinates obtained by the laser displacement receiving light screen are the displacement changes.

Optionally, after each blasting, the coordinates of the rock mass measurement points obtained by the laser displacement receiving light screen are the cumulative displacement changes.

Optionally, the displacement change caused by the current blasting can be obtained by subtracting the coordinates of the rock mass measurement points before and after the zone blasting.

In summary, the segmented multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face provided in this embodiment can monitor the multi-directional displacement of rock and soil in each blasting sub-area in real time during the continuous blasting construction of the tunnel. It only requires one This kind of measuring device can realize the displacement detection of multiple blasting areas, and the test cost is low. Moreover, the device has a simple structure, is easy to bury, is simple to operate and easy to master, and the device can be reused, so the cost of testing is lower. In addition, the overall hardness of this device is relatively large, it is not easily affected by changes in the external environment, and the data measurement accuracy is high.

This embodiment provides a testing method based on a multi-directional displacement detection device of unexcavated rock mass in front of the segmented tunnel face. The steps are as follows:

Step A1. Preparation outside the hole before measurement: Preliminarily set up the laser displacement receiver and connect it to the console, assemble the segmented multi-point laser displacement instrument, determine the drilling length and drilling diameter; prepare the grouting pipe and mix the slurry .

Step A2. Drilling measurement holes: Carry out drilling construction for long-distance buried holes on the tunnel face, and use RPD-75SL-H2 multi-function drilling machine to drill and clean the holes.

Step A3, bury the instrument and grout: Push the main body of the segmented multi-point laser displacement instrument into the drill hole, and adjust it to the appropriate position for fixation. Cement slurry is injected through the grouting pipe to fill the gap between the segmented multi-point laser displacement meter and the borehole, so that the fixed detection unit of the segmented multi-point laser displacement meter is integrated with the formation and remains stationary until solidified.

Step A4, reset the instrument to zero: first turn on the laser transmitter and laser repeater, so that the laser can pass through the laser clearer smoothly and be mapped on the laser displacement refractor. Then adjust the laser displacement receiving light screen to adjust the laser displacement transmitted through the laser displacement refractor to coordinates (0, 0).

Step A5: Carry out tunnel construction and record the rock mass extrusion deformation value and rock mass displacement data: turn on data recording, and after the tunnel construction blasting and its changes, continue to record the rock mass extrusion deformation value at each time point in each gap. and rock mass displacement data. At the same time, after each blasting, remove the stabilizing plate and laser channel that may remain in the blasted section to ensure the smoothness of the laser channel in the front layer; the cycle repeats until the excavation is completed.

Step A6, data processing: After collecting and recording data at different measuring points, the data can be processed to obtain the settlement displacement, horizontal displacement and extrusion displacement of the soil at different depth measuring points along the tunnel axis.

In some embodiments, the segmented multi-directional displacement detection device of the unexcavated rock mass in front of the tunnel face provided by this solution enables multi-point detection of the unexcavated rock mass in front of the tunnel face during conventional blasting and excavation of the tunnel. The deformation measurement of vault settlement, horizontal displacement and extrusion displacement can effectively solve the vacuum monitoring during construction and realize the measurement of multi-directional displacement of rock mass in one drilling, minimizing the need for multiple drilling and installation of equipment. human factors, thereby improving measurement accuracy and convenience.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the scope of the technical solutions of the embodiments of the present invention. , they should all be covered by the scope of the claims and description of the present invention.

Claims (10)

1. Multidirectional displacement detection device of excavation rock mass in place ahead in segmented tunnel face, its characterized in that includes:

the sectional type multi-point laser displacement instrument is buried in the non-excavated rock body in front of the tunnel face and is used for measuring the non-excavated rock body in front of the tunnel face to obtain a rock body extrusion deformation value and a laser displacement signal;

the laser displacement receiver is fixed on the ground of the tunnel and is used for receiving laser displacement signals sent by the sectional type multipoint laser displacement instrument and acquiring rock mass displacement data according to the laser displacement signals; the rock mass displacement data comprise a rock mass horizontal displacement amount and a vault settlement displacement amount.

2. The apparatus according to claim 1, characterized by comprising: the grouting pipe is fixed above the sectional type multipoint laser displacement instrument through a clamping groove.

3. The apparatus of claim 1, wherein the segmented multipoint laser displacer comprises:

the fixed detection unit is buried in the non-excavated rock body in front of the tunnel face and is used for measuring the non-excavated rock body to obtain a rock body extrusion deformation value and a plurality of initial laser signals;

the detachable unit is in communication connection with the fixed detection unit; the detachable unit is used for receiving a plurality of initial laser signals and acquiring laser displacement signals according to the initial laser signals.

4. A device according to claim 3, wherein the stationary detection unit comprises:

the laser measuring device comprises a plurality of laser channels, a plurality of laser relays and a spring measuring rod, wherein the laser channels are internally provided with the plurality of laser relays, and the other end of each laser channel is connected with one end of the spring measuring rod;

the other end of the spring measuring rod is connected with one end of the laser transmitter;

the other end of the laser transmitter is connected with the anchor head;

and the displacement sensor is fixed at the connecting end of the laser channel and the spring measuring rod.

5. The apparatus of claim 4, wherein the non-excavated rock mass in front of the tunnel face is a region to be blasted, the region to be blasted being divided into a plurality of sub-regions to be blasted in the order of the front and rear of the blasting; the fixed detection unit traverses each sub-area to be blasted; each laser repeater in the fixed detection unit is arranged at the dividing surface between each sub-area to be blasted.

6. The apparatus of claim 4 wherein the number of laser repeaters in each laser channel is different and a photosensor is disposed in each laser repeater.

7. The apparatus of claim 4, wherein the stationary detection unit further comprises:

the laser relay protection tube is arranged at the periphery of the laser channel corresponding to the laser relay and is used for protecting the laser relay;

the sealing head is arranged between the laser channel and the spring measuring rod and is used for sealing and protecting an inlet of the laser channel;

and the stabilizing disc is used for wrapping all the laser channels and fixing the laser channels.

8. The apparatus of claim 4, wherein the detachable unit comprises:

the laser displacement refractor is arranged at one side of the laser clarity instrument;

and the other side of the laser clear instrument is connected with the laser channel.

9. The apparatus of claim 1, wherein the laser displacement receiver comprises:

the laser displacement receiving light screen is used for receiving the laser displacement signals refracted by the laser displacement refractor;

the calibration laser is used for laser calibration;

and the laser signal converter is used for converting the laser displacement signal into an electric signal.

10. The apparatus according to claim 1, characterized by comprising:

and the control console is respectively connected with the laser displacement receiver and the sectional type multi-point laser displacement instrument and is used for receiving rock mass displacement data and rock mass extrusion deformation values and displaying and storing the rock mass displacement data and the rock mass extrusion deformation values in real time.