A monitoring device and method for settlement of working base point of a steep slope tunnel

Abstract

The invention discloses a monitoring device and method for the settlement of a working base point of a steep-slope tunnel, comprising a square-shaped fixed frame, which is fixedly connected to a transverse support rod; an adjusting rod, which is connected to the fixed sleeve by two fastening bolts penetrating the fixed sleeve; an inclined block is also provided at the end of the adjusting rod, and a reflective plate is provided on the inclined surface of the inclined block; the fixed frame is connected to a telescopic rod at the bottom, and a mounting bracket is provided at the bottom of the telescopic rod, on which a first static level connected to a water storage tank and a second static level arranged at a point to be observed and connected to the water storage tank are fixed, so that a set of instruments can be used to meet the measurement requirements for different types of points to be measured, such as settlement of tunnel base surface, convergence of tunnel wall, sinking of arch crown, convergence deformation of section, etc., while reducing system errors to a certain extent and obtaining more accurate data results.

Description

Technical Field

[0001] The invention relates to the field of settlement detection devices, in particular to a monitoring device and method for settlement of a working base point of a steep-slope tunnel. Background Art

[0002] In recent years, with the rapid development of transportation construction, tunnel projects have increasingly crossed soft strata and high-stress sections with poor geology, and various collapses, water gushing, bottom bulges, and large deformations often occur. Bottom bulges are one of the more common ones. Once they occur, their deformation continues to be uncertain, leaving major hidden dangers for engineering construction and later operations. When the bottom bulge of the invert appears in a tunnel or tunnel, it is generally remedied afterwards; if the poor geological section is not monitored in place and handled in time, the tunnel floor (invert) after the second lining is applied during construction is prone to cracking and need to be replaced; if the bottom bulge of the invert is serious during operation, it is easy to reduce the speed of operation, all of which will cause large economic losses and adverse social impacts.

[0003] At present, the total station and level are mostly used in the construction process of tunnel invert settlement observation. The main problem is that the measuring point is easy to be damaged, and each measurement requires 3 to 4 people, which is time-consuming and laborious. The use of differential pressure static level for measurement is common in operating tunnels, but it is difficult to use differential pressure static level in tunnel construction, especially in steep slope tunnels. The main reason is that the large range and high accuracy cannot be achieved at the same time.

[0004] The method usually adopted for automatic monitoring of invert settlement is to first set up an appropriate number of benchmark points at a stable location outside the settlement range. In order to shorten the distance from the benchmark point to the observation point and reduce the elevation error of the observation point, a relatively stable point can also be selected as the working benchmark point within the settlement range. Secondly, the observation point is buried in the observation area. The difference in elevation of the same observation point measured twice on different dates represents the change of the ground observation point during these two observations. Automatic monitoring mostly monitors the elevation change between the observation point and the working benchmark point. Since the working benchmark point itself has elevation changes, the difference in elevation of the same observation point measured twice on different dates may not be the difference in elevation of its relative benchmark point. The current market generally adopts the method of installing a static level at the working base point and the reference point, connecting the static level with the water tank with a connecting pipe, and the water surface must be higher than the pressure detection sensor in the static level. The pressure of the corresponding static level at the working base point and the reference point is detected respectively, and then the pressure is converted into the elevation value of the water tank liquid surface, and then the difference between the two elevation values ​​is calculated. Since the elevation of the reference point is constant, the change value of the difference between the two elevation values ​​measured twice on different dates is the change value of the elevation of the working base point. Since the accuracy of the existing static level in the market is 1‰FS, that is, the accuracy of the static level with a range of 1m is 1mm, and most tunnels have a large slope, and the distance between the reference point and the working base point is far, if a large-range static level is used, the measurement accuracy naturally cannot meet the 1mm requirement of the specification, and the use of benchmark superposition (two static levels are rigidly connected up and down) will cause cumulative errors. Summary of the invention

[0005] The technical problem to be solved by the present invention is that in the automatic monitoring of the settlement of the invert arch of a steep tunnel, if a pressure difference static level is used as a reference point, the reference point and the working base point are far apart and the height difference is large, which will lead to the measurement accuracy failing to meet the requirement of within 1 mm in the monitoring specification. However, if a working base point is added in the middle, the installation process will be cumbersome and prone to large cumulative errors. In addition, the connecting pipes between the monitoring sections during tunnel construction are long, and the connecting pipes are inconvenient to install and prone to damage.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a monitoring device for the settlement of the working base point of a steep tunnel is provided, comprising a fixing rod horizontally placed in the working base point on the tunnel wall, an omnidirectional pan-tilt head is connected to the end of the fixing rod through a connecting pipe sleeved on the outside of the fixing rod, a movable sphere of the omnidirectional pan-tilt head is connected to a triangular prism with a right angle in the cross section, a reflector is provided on the inclined surface of the triangular prism, and a horizontal bubble is provided on the vertical surface of the triangular prism; a connecting piece is sleeved between the connecting pipe and the omnidirectional pan-tilt head, and two plum handle screws penetrating the connecting pipe are also provided at the end of the connecting pipe; the lower end of the connecting piece is connected to a mounting bracket located at the working base point of the cross section through a telescopic rod, a first static level connected to a liquid storage tank installed on the tunnel wall is provided on the mounting bracket, and a second static level is also provided at an observation point, and the liquid level of the liquid storage tank is higher than the first static level and the second static level; and a laser rangefinder is also provided at a reference point.

[0007] Particularly, the cross section of the triangular prism is an isosceles right triangle.

[0008] Particularly, the laser of the laser rangefinder is emitted horizontally into the reflective plate.

[0009] A monitoring method of a monitoring device for the settlement of a working base point of a steep slope tunnel comprises the following steps:

[0010] Step 1, determine the working base point, install the monitoring device on the working base point, level the triangular prism through the horizontal bubble on the triangular prism; measure the upper angle of the cross section of the triangular prism to be α; reserve or dig an installation hole at the observation point, install the second static level and connect the liquid storage tank and the monitoring device through a connecting pipe;

[0011] Step 2, adjust the angle of the laser transmitter so that the laser is projected onto the reflective plate on the inclined surface of the triangular prism;

[0012] Step 3, calculate the actual settlement value of the observation point; the height difference between the first static level and the liquid level of the liquid storage tank in the initial state is recorded as JZ1, and the height difference between the second static level and the liquid level of the liquid storage tank is recorded as GC1, then the height difference between the first static level and the second static level is H1=GC1-JZ1, the angle between the laser and the horizontal line of the laser rangefinder in the initial state is recorded as β, and the distance from the laser rangefinder to the reflector is recorded as X1; when measuring again after 24 hours, the height difference between the first static level and the liquid level of the liquid storage tank is recorded as JZ2, and the height difference between the second static level and the liquid level of the liquid storage tank is recorded as GC1. The difference is recorded as GC2. At this time, the height difference between the first static level and the second static level is H2=GC2-JZ2. The distance from the laser rangefinder to the reflector is recorded as X2. At this time, the angle between the laser of the laser rangefinder and the horizontal line is still β. The self-settlement of the working base point of the section is CJ2=(X2·COSβ-X1·COSβ)·tanα. The actual settlement value of the observation point is CJ1=H2-H1+CJ1=(GC2-JZ2)-(GC1-JZ1)+(X2·COSβ-X1·COSβ)·tanα.

[0013] The beneficial effects of the present invention are as follows: since in the existing settlement measurement method of a steep tunnel, the distance between the reference point and the observation point is usually far, the present invention reduces the distance by setting up a working reference point near the observation point, while reducing the height difference between the working reference point and the observation point, making it easier to use a small-range static level, such as a 10 cm range static level, so that the measurement result has a significant improvement in accuracy, meets the requirements of monitoring specifications, and reduces the requirement that the observation point is close to the reference point; at the same time, the device has a simple structure, reducing the risk of the connecting pipe being easily damaged due to the excessive length of the pipeline during use; the operation is convenient, and the actual requirements for high accuracy and simplified measurement device structure in automatic monitoring of the settlement of the steep tunnel invert are realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the device of the present invention.

[0015] Figure 2 It is a schematic diagram of the use status of the device of the present invention.

[0016] Figure 3 It is a schematic diagram of the principle of the device of the present invention.

[0017] Among them, working base point - 1; section working base point - 11; observation point - 12; fixing rod - 2; connecting pipe - 3; connecting piece - 31; plum handle screw - 32; omnidirectional pan-tilt head - 4; movable sphere - 41; triangular column - 5; reflector - 51; level bubble - 52; telescopic rod - 6; mounting bracket - 7; first static level - 71; second static level - 72; liquid storage tank - 8; reference point - 9; laser rangefinder - 91. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings.

[0019] A monitoring device for the settlement of a working base point in a steep-slope tunnel comprises a fixing rod 2 which is horizontally placed at a working base point 1 on a tunnel wall, wherein an omnidirectional pan-tilt head 4 is connected to the end of the fixing rod 2 through a connecting pipe 3 which is sleeved on the outside of the fixing rod 2, wherein an active sphere 41 of the omnidirectional pan-tilt head 4 is connected to a triangular column 5, a reflector 51 is provided on the inclined surface of the triangular column 5, and a horizontal bubble 52 is provided on the vertical surface of the triangular column 5; a connecting piece 31 is sleeved between the connecting pipe 3 and the omnidirectional pan-tilt head 4, and a connecting piece 31 is sleeved on the connecting pipe 3 and the omnidirectional pan-tilt head 4. The end of the connecting pipe 3 is also provided with two plum handle screws 32 that penetrate the side wall of the connecting pipe 3; the lower end of the connecting piece 31 is connected to the mounting bracket 7 located at the section working base point 11 through the telescopic rod 6, and the mounting bracket 7 is provided with a first static level 71 connected to the liquid storage tank 8 installed on the tunnel wall, and also includes a second static level 72 arranged at the observation point 12, and the liquid level of the liquid storage tank 8 is higher than the first static level 71 and the second static level 72; it also includes a laser rangefinder 91 arranged at the reference point 9.

[0020] As a preferred embodiment, the cross section of the triangular prism 5 is an isosceles right triangle.

[0021] As a preferred embodiment, the laser of the laser rangefinder 91 is emitted horizontally into the reflective plate 51 .

[0022] A monitoring method of a monitoring device for the settlement of a working base point of a steep slope tunnel comprises the following steps:

[0023] Step 1, determine the working base point 1, install the monitoring device on the working base point 1, level the triangular prism through the horizontal bubble 52 on the triangular prism 5; measure the upper angle of the cross section of the triangular prism 5 to be α; reserve or dig an installation hole at the observation point 12, install the second static level and connect the liquid storage tank 8 and the monitoring device through a connecting pipe;

[0024] Step 2, adjust the angle of the laser emitter so that the laser is projected onto the reflector 51 on the inclined surface of the triangular prism 5;

[0025] Step 3, calculate the actual settlement value of the observation point; the height difference between the first static level 71 and the liquid level of the liquid storage tank 8 in the initial state is recorded as JZ1, and the height difference between the second static level 72 and the liquid storage tank 8 is recorded as GC1, then the height difference between the first static level 71 and the second static level 72 is H1=GC1-JZ1, the angle between the laser of the laser rangefinder 91 and the horizontal line in the initial state is recorded as β, and the distance from the laser rangefinder 91 to the reflector 51 is recorded as X1; after 24 hours, During measurement, the height difference between the first static level 71 and the liquid level of the liquid storage tank 8 is recorded as JZ2, and the height difference between the second static level 72 and the liquid level of the liquid storage tank 8 is recorded as GC2. At this time, the height difference between the first static level 71 and the second static level 72 is H2=GC2-JZ2, and the distance from the laser rangefinder 91 to the reflector 51 is recorded as X2. At this time, the angle between the laser of the laser rangefinder 91 and the horizontal line is still β, and the self-sedimentation of the cross-section working base point 11 is also the self-sedimentation CJ of the working base point 1. 2= (X2-X1)·COSβ·tanα, then the actual settlement value of the observation point CJ1=H2-H1+CJ1=(GC2-JZ2)-(GC1-JZ1)+(X2·COSβ-X1·COSβ)·tanα.

[0026] The working principle of the present invention is as follows: after the installation and erection of the device is completed, when the working base point 1 itself has not settled, since the working base point 1 and the section working base point 11 are rigidly connected, the section working base point 11 has not settled; at this time, the settlement change value of the observation point 12 relative to the section working base point 11 is the actual settlement value relative to the reference point 9; when the working base point 1 itself settles, the actual settlement value of the observation point 12 plus the height difference between the observation point 12 and the section working base point 11 in the initial state is equal to the height difference between the observation point 12 and the section working base point 11 during the secondary measurement plus the settlement value of the section working base point 11 itself. The initial distance X1 between the reference point 9 in the initial state, i.e., the point where no settlement will occur, and the reflector 51 set on the inclined surface of the triangular prism 5 in the device is measured by the laser rangefinder 91. After 24 hours, the distance X2 between the reference point 9 and the reflector 51 is measured again. The cosine value of the angle β of the difference X2-X1 between the two measured distances is the displacement component of the distance difference in the horizontal direction, i.e., (X2-X1)·COSβ. The angle α of the upper part of the cross section of the triangular prism 5 is used to calculate the displacement of the working base point 1 in the horizontal direction. The displacement component in the vertical direction is (X2-X1)·COSβ·tanα. The first static level 71 connected to the liquid storage tank 8 and the second static level 72 set at the observation point 12 are used to measure the height difference between the first static level 71 and the observation point 12, which is (GC2-JZ2)-(GC1-JZ1). The height difference plus the displacement component of the working base point 1 in the vertical direction (X2-X1)·COSβ·tanα can obtain the actual settlement value of the observation point 12. Since the settlement of the working base point 1 is also included in the range of variation during the measurement process, it plays a greater role in improving the accuracy of the measurement results; at the same time, since the relative height of the observation point 12 is determined by the second static level 72 and the liquid storage tank 8, and the second static level 72 is buried at the observation point, the measurement range of the data not only includes the surface range of the construction site, but also can be used to measure the actual settlement conditions of different soil layers at different depths by burying the second static level 72 at different depths.

[0027] For the convenience of calculation, when the triangular cross-section of the triangular prism 5 is an isosceles right triangle, the horizontal component of the two distance changes measured by the laser rangefinder 91 is equal to the vertical elevation change of the working base point 1, that is, the value of (X2-X1)·COSβ is the same as the settlement elevation value of the working base point 1.

[0028] When the laser of the laser rangefinder 91 is horizontally incident on the reflector 51, the angle β is 0°, and the change value of the two distances measured by the laser rangefinder 91, namely X2-X1, is the settlement value of the working base point 1, which is easier to calculate.

[0029] The terms “connection” and “fixation” mentioned in the description of the present invention may refer to fixed connection, processing and forming, welding or mechanical connection. The specific meanings of the above terms in the present invention shall be understood according to the specific circumstances.

[0030] In the description of the present invention, the terms "center", "upper", "lower", "horizontal", "inside", "outside", etc., which indicate the orientation or position relationship, are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying a specific orientation that the device or element referred to must have, and therefore cannot be understood as a limitation on the present invention.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A monitoring device for the settlement of a working base point in a steep slope tunnel, characterized in that: The invention comprises a fixing rod (2) horizontally inserted into a working base point (1) on a tunnel wall; an omnidirectional pan-tilt head (4) is connected to the end of the fixing rod (2) via a connecting pipe (3) sleeved on the outside of the fixing rod (2); a movable sphere (41) of the omnidirectional pan-tilt head (4) is connected to a triangular column (5); the cross section of the triangular column (5) is an isosceles right triangle; a reflector (51) is provided on the inclined surface of the triangular column (5); and a horizontal bubble (52) is provided on the vertical surface of the triangular column (5); a connecting piece (31) is sleeved between the connecting pipe (3) and the omnidirectional pan-tilt head (4); and two plum blossoms (51) penetrating the side wall of the connecting pipe (3) are provided at the end of the connecting pipe (3). A spiral handle screw (32); the lower end of the connecting member (31) is connected to a mounting bracket (7) located at a cross-section working base point (11) via a telescopic rod (6); a first static level (71) connected to a liquid storage tank (8) installed on a tunnel wall is provided on the mounting bracket (7); a second static level (72) is provided at an observation point (12); and the liquid level of the liquid storage tank (8) is higher than the first static level (71) and the second static level (72); and a laser rangefinder (91) is provided at a reference point (9); a laser of the laser rangefinder (91) is horizontally projected into the reflector (51) to measure the distance between the laser rangefinder (91) and the reflector (51).

2. The monitoring method of the monitoring device for the settlement of the working base point of a large-slope tunnel according to claim 1 is characterized in that: The following steps are involved: Step 1, determine the working base point (1), install the monitoring device on the working base point (1), level the triangular prism (5) through the level bubble (52) on the triangular prism (5); measure the upper angle of the cross section of the triangular prism (5) as α; reserve or excavate an installation hole at the observation point (12), and connect the liquid storage tank (8) and the monitoring device through a connecting pipe; Step 2, setting up a laser rangefinder (91) at the reference point (9), and adjusting the angle of the laser emitter so that the laser is projected onto the reflective plate (51) on the inclined surface of the triangular prism (5); Step 3, calculating the actual settlement value of the observation point; in the initial state, the height difference between the first static level (71) and the liquid level of the liquid storage tank (8) is recorded as JZ1, and the height difference between the second static level (72) and the liquid level of the liquid storage tank (8) is recorded as GC1, then the height difference between the first static level (71) and the second static level (72) in the initial state is H1=GC1-JZ1, the angle between the laser beam of the laser rangefinder (91) and the horizontal line in the initial state is recorded as β, and the distance from the laser rangefinder (91) to the reflector (51) is recorded as X1; when measuring again after 24 hours, the height difference between the first static level (71) and the liquid storage tank (8) is recorded as JZ2, and the height difference between the second static level (72) and the liquid storage tank (8) is recorded as GC2, then the height difference between the first static level (71) and the second static level (72) is recorded as GC2. The height difference between the laser rangefinder (71) and the second static level (72) is H2=GC2-JZ2, and the distance from the laser rangefinder (91) to the reflector (51) is recorded as X2. At this time, the angle between the laser of the laser rangefinder (91) and the horizontal line is still β. The self-sedimentation of the cross-section working base point (11), that is, the self-sedimentation of the working base point (1) CJ2={[(X2-X1) / sinα]·sinβ·cosα+(X2-X1)·cosβ}·tanα, then the actual settlement value of the observation point (12) CJ1=H2-H1+CJ2=(GC2-JZ2)-(GC1-JZ1)+{[(X2-X1) / sinα]·sinβ·cosα+(X2-X1)·cosβ}·tanα.

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