CN218884945U - Stratum settlement monitoring device for model test - Google Patents

Abstract

The utility model provides a stratum settlement monitoring device for model test, which comprises a protection tube, a protection shell, a bracket and a displacement measuring element, wherein the protection tube is buried in a land filling layer along the up-down direction, and the lower end of the protection tube is connected with a bottom sealing tube by screw threads; the protective shell is slidably sleeved on the periphery of the protective tube, and a measuring rod which penetrates through the protective tube along the radial direction and is in sliding fit with the protective tube along the axial direction is arranged in the protective shell; the bracket is erected above the protection tube and is connected with the concrete floor; the displacement measurement component is connected on the support, and displacement measurement component's wiring end is connected with and is used for the survey line that links to each other with the measuring staff, and the survey line can follow the measuring staff and reciprocate. The utility model provides a stratum settlement monitoring device for model test through the mutual restriction of protective housing and protection tube on the horizontal direction to the relative position of measuring staff and protection tube horizontal direction is stable when guaranteeing to bury underground, avoids the inner wall of survey line and protection tube to take place the friction and interferes, thereby realizes subsiding the accurate measurement of value to the filled-up stratum.

Description

Stratum settlement monitoring device for model test

Technical Field

The utility model belongs to the technical field of settlement monitoring, more specifically say, relate to a model test land used layer settlement monitoring device.

Background

In order to reveal the stratum settlement rule caused by tunnel excavation, theoretical analysis, numerical calculation and model test can be adopted. However, due to the complexity of stratum conditions, the acquisition of stratum calculation parameters and constitutive models is difficult to conform to the actual engineering, and the influence of tunnel construction on stratum settlement can only be qualitatively obtained through theoretical analysis and numerical tests; and a model material similar to the actual stratum can be prepared by adopting a model test method through a similar theory, so that a settlement rule more similar to the actual construction process is obtained.

When the tunnel construction process is simulated through a model test, the stress field of the filled ground layer around the tunnel is changed due to the excavation of the tunnel, and meanwhile, the filled ground layer above the tunnel is settled. Because the settlement that produces in the model test is less, the stratum settlement monitoring devices who adopts at present generally is to connect the survey line at displacement sensor's wiring end to the protection tube is established to the cover on the survey line, and the survey line extends out and connects the iron sheet at the lower port of protection tube, buries protection tube and iron sheet underground in the filled-up stratum, and wherein the protection tube is buried underground in vertical direction, and the iron sheet is located the below of protection tube lower port, and the settlement numerical value in the filled-up stratum of quilt survey is reachd through the settlement volume of iron sheet. However, in the burying process, the protection pipe is extruded by filling soil, so that the protection pipe is easy to shift to one side of the iron sheet along the horizontal direction, and the measuring line is further driven to be in contact with the inner wall of the protection pipe. In the process of iron sheet settlement, the measuring line can generate friction interference with the inner wall of the protection tube, so that the settlement of the iron sheet is reduced, and the measured settlement value of the filled earth stratum is inaccurate.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a stratum settlement monitoring device for model test can make survey line and protection tube horizontal direction's relative position stable burying the in-process underground, avoids the inner wall contact of survey line and protection tube and takes place the friction interference in the measurement process, makes measuring settlement numerical value more accurate.

In order to achieve the above object, the utility model adopts the following technical scheme: the stratum settlement monitoring device for the model test comprises a protection pipe, a protection shell, a support and a displacement measuring element, wherein the protection pipe is buried in a land filling layer along the vertical direction, and the lower end of the protection pipe is in threaded connection with a bottom sealing pipe; the protective shell is slidably sleeved on the periphery of the protective tube, and a measuring rod which penetrates through the protective tube along the radial direction and is in sliding fit with the protective tube along the axial direction is arranged in the protective shell; the bracket is erected above the protection tube and is connected with the concrete floor; the displacement measurement component is connected on the support, and displacement measurement component's wiring end is connected with and is used for the survey line that links to each other with the measuring staff, and the survey line can be followed the measuring staff and reciprocated.

In a possible implementation manner, the protection tube comprises a first sleeve and a second sleeve, and the first sleeve is sleeved on the periphery of the measuring line; the second sleeve is sleeved at the lower end of the first sleeve in a threaded manner, a sliding groove which extends to the upper edge of the second sleeve along the axial direction of the second sleeve is arranged on the peripheral wall of the second sleeve in a penetrating manner, the protective shell is sleeved on the peripheries of the first sleeve and the second sleeve in a sliding manner, and the measuring rod is connected in the sliding groove in a sliding manner.

In some embodiments, two sliding grooves are symmetrically arranged on the peripheral wall of the second sleeve, and two ends of the measuring rod respectively extend to the outside of the two sliding grooves.

In a possible implementation manner, threaded holes are symmetrically formed in two opposite side walls of the protective shell, and the measuring rod is in threaded connection with the threaded holes.

In a possible implementation mode, the protection tube and the displacement measuring element are provided with a plurality of protection tubes, the plurality of protection tubes are sequentially in threaded connection from top to bottom, the bottom sealing tube is connected with the protection tube at the bottom, measuring rods are arranged on each protection tube in a sliding fit mode, and the plurality of displacement measuring elements are connected with the plurality of measuring rods in a one-to-one mode.

In some embodiments, the projections of two adjacent measuring bars on the horizontal plane form an included angle.

In a possible implementation, the displacement measuring element comprises two displacement sensors, the wiring end of each displacement sensor is connected with a measuring line, and the two measuring lines are respectively arranged close to two ends of the measuring rod.

In some embodiments, the bracket is horizontally provided with a mounting plate, and the displacement sensor is connected to the bottom surface of the mounting plate.

In one possible implementation, a reel on which the spindle extends in the horizontal direction is rotatably connected to the bracket, and the measuring wire is wound around the reel.

In one possible implementation, the protective shell is square in cross-section.

The embodiment of the application provides a stratum settlement monitoring device for model test, in its actual use, set up the support on concrete ground, in order to guarantee the stability on support place ground, then bury protection tube and protective housing in the filled soil stratum that needs measurement underground, wherein the protection tube is vertical state and buries underground, and bury from the bottom upwards, the lower extreme opening that the back cover pipe is used for the shutoff protection tube, avoid getting into debris in the protection tube, protective housing and protection tube separate survey line and filled soil stratum, improve the precision of subsiding numerical value, when taking place to subside in the filled soil stratum of protection housing position, can drive the protective housing and slide downwards along the protection tube, and then make survey pole pulling survey line remove downwards, data signal through making data acquisition system receipt and processing displacement measurement element send reachs the numerical value of subsiding.

The utility model provides a stratum settlement monitoring device for model test, compared with the prior art, locate on the protection tube through the protective housing cover, the measuring staff is connected with the protective housing and follows axial sliding fit with the protection tube, under the mutual restriction on protection housing and protection tube horizontal direction, when burying underground in order to guarantee, measuring staff and protection tube horizontal direction relative position's stability, avoid the inner wall contact of survey line and protection tube and take place the friction interference at the measurement process, thereby realize the accurate measurement to the value of subsiding in the filled soil stratum.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive labor.

Fig. 1 is a schematic structural diagram of a formation settlement monitoring device for model test provided by an embodiment of the present invention;

fig. 2 is a schematic structural view of the hidden support and the filled earth layer in fig. 1 according to the embodiment of the present invention;

fig. 3 is a schematic front sectional structural view of the protection tube, the protection shell, the measuring line, the bottom sealing tube and the measuring rod in fig. 2 according to the embodiment of the present invention;

fig. 4 is a schematic structural view of the measuring line and the measuring rod in the embodiment of the present invention in fig. 2;

fig. 5 is a schematic structural view of the second sleeve in fig. 2 according to an embodiment of the present invention;

fig. 6 is a schematic structural view of the first sleeve in fig. 2 according to an embodiment of the present invention.

Wherein, in the figures, the various reference numbers:

1. a filled earth formation; 10. a support; 11. mounting a plate; 20. a displacement measuring element; 21. a displacement sensor; 211. measuring a line; 30. protecting the tube; 31. a second sleeve; 311. a chute; 32. a first sleeve; 40. sealing the bottom tube; 50. a reel; 60. a protective shell; 70. a measuring rod.

Detailed Description

In order to make the technical problem, technical solution and advantageous effects to be solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or be indirectly on the other element. It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention. The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

Referring to fig. 1 to 6, a description will now be given of a formation settlement monitoring device for a model test according to the present invention. The stratum settlement monitoring device for the model test comprises a protection pipe 30, a protection shell 60, a support 10 and a displacement measuring element 20, wherein the protection pipe 30 is embedded in a soil filling stratum 1 along the vertical direction, and the lower end of the protection pipe is in threaded connection with a bottom sealing pipe 40; the protective shell 60 is slidably sleeved on the periphery of the protective tube 30, a measuring rod 70 which penetrates through the protective tube 30 along the radial direction and is in sliding fit with the protective tube 30 along the axial direction is arranged in the protective shell 60, and the measuring rod 70 is connected with the protective shell 60; the bracket 10 is erected above the protection pipe 30 and is connected with the concrete floor; the displacement measuring element 20 is connected to the support 10, and a measuring wire 211 for connecting with the measuring bar 70 is connected to a terminal of the displacement measuring element 20, and the measuring wire 211 can move up and down along with the measuring bar 70.

Because the settlement values of the filled earth strata at different depths are different, and the settlement value of the upper filled earth stratum is very small and can be ignored, the lower protection pipe 30 can not be settled under the limitation of the upper filled earth stratum.

The displacement measuring element 20 is electrically connected to the data acquisition system, and the displacement measuring element 20 is used for measuring data and transmitting the data to the data acquisition system.

The embodiment of the application provides a stratum settlement monitoring device for model test, in its actual use, set up support 10 on concrete ground, in order to guarantee the stability on support 10 place ground, then bury protection tube 30 and protective housing 60 in the filled-in stratum 1 that needs the measurement, wherein protection tube 30 is vertical state and buries underground, and bury from the bottom upwards, back cover pipe 40 is used for the lower extreme opening of shutoff protection tube 30, avoid getting into debris in the protection tube 30, protective housing 60 and protection tube 30 separate survey line 211 and filled-in stratum 1, improve the precision of settlement numerical value, when taking place to subside at the filled-in stratum 1 of protection housing 60 position, can drive protective housing 60 along protection tube 30 lapse, and then make survey pole 70 pulling survey line 211 move downwards, obtain settlement numerical value through making data acquisition system receive and handle the data signal that displacement measurement component 20 sent.

The utility model provides a stratum settlement monitoring device for model test, compared with the prior art, locate the protection tube 30 through the protective housing 60 cover on, measuring staff 70 is connected with protective housing 60 and follows axial sliding fit with protection tube 30, under the mutual restriction in protective housing 60 and protection tube 30 horizontal direction, when burying underground in order to guarantee, measuring staff 70 and protection tube 30 horizontal direction relative position's stability, avoid the inner wall contact of survey line 211 and protection tube 30 and take place the friction interference in the measurement process, thereby realize the accurate measurement to filling ground layer 1 settlement value.

In a possible implementation manner, the protection tube 30 adopts the structure as shown in fig. 2 to 6, and referring to fig. 2 to 6, the protection tube 30 includes a first sleeve 32 and a second sleeve 31, the first sleeve 32 is sleeved on the periphery of the measuring line 211; the second sleeve 31 is screwed on the lower end of the first sleeve 32, a sliding groove 311 extending to the upper edge of the second sleeve 31 along the axial direction of the second sleeve 31 is arranged on the peripheral wall of the second sleeve 31 in a penetrating manner, the protective shell 60 is slidably sleeved on the peripheries of the first sleeve 32 and the second sleeve 31, and the measuring rod 70 is slidably connected in the sliding groove 311.

Specifically, the measuring line 211 is located in the first sleeve 32 and the second sleeve 31, the upper port of the first sleeve 32 is located above the filled soil stratum 1, the filled soil is effectively prevented from entering the first sleeve 32 and the second sleeve 31, the upper end and the lower end of the first sleeve 32 are both provided with external threads, the upper end and the lower end of the second sleeve 31 are both provided with internal threads, the protective shell 60 is used for shielding the sliding groove 311, the filled soil is prevented from entering the second sleeve 31 from the sliding groove 311, so that the accuracy of sedimentation value measurement is affected, and after the first sleeve 32 is in threaded connection with the second sleeve 31, a sufficient distance is provided between the lower end of the first sleeve 32 and the inner bottom wall of the sliding groove 311, so that the measuring rod 70 can move up and down, that is, a sufficient distance is provided between the measuring rod 70 and the inner bottom wall of the sliding groove 311, the contact between the measuring rod 70 and the inner bottom wall of the sliding groove 311 in the sedimentation process of the filled soil stratum 1 is avoided, and the accuracy of sedimentation value measurement is ensured.

The bottom sealing pipe 40 is screwed on the lower end of the second casing 31 and is used for sealing the port at the lower end of the second casing 31 and preventing the second casing 31 from entering the filling soil.

In some embodiments, two sliding grooves 311 are symmetrically disposed on the peripheral wall of the second sleeve 31, and two ends of the measuring rod 70 extend to the outside of the two sliding grooves 311.

Specifically, the two slide slots 311 are provided, so that the measuring rod 70 can stably slide along the axial direction of the second sleeve 31, and meanwhile, the measuring rod 70 is prevented from interfering with the second sleeve 31 during the moving process.

In a possible implementation manner, the protective shell 60 is structured as shown in fig. 2 and 3, referring to fig. 2 and 3, threaded holes are symmetrically formed in two opposite side walls of the protective shell 60, and the measuring rod 70 is in threaded connection with the threaded holes.

Specifically, the threaded connection of the measuring rod 70 and the protective shell 60 increases the stability of the connection between the measuring rod 70 and the protective shell 60, and simultaneously prevents earth from entering the protective shell 60 from a gap between the threaded hole and the measuring rod 70.

This may be used in conjunction with the features of the first sleeve 32, the second sleeve 31, and the chute 311 described above. During installation, the bottom sealing pipe 40 is in threaded connection with the second sleeve 31, the measuring rod 70 is in threaded connection with the protective shell 60, the measuring line 211 penetrates into the first sleeve 32 and penetrates out of the lower end of the first sleeve 32 to be connected with the measuring rod 70, then the first sleeve 32 and the second sleeve 31 penetrate into the protective shell 60 from the upper side and the lower side of the protective shell 60 respectively, the measuring rod 70 is located in the sliding groove 311, the first sleeve 32 and the second sleeve 31 are in threaded connection with the protective shell 60, only the first sleeve 32 needs to be rotated in the process of threaded connection of the first sleeve 32 and the second sleeve 31, interference between rotation of the second sleeve 31 and the measuring rod 70 is avoided, the measuring rod 70 is installed and embedded in the soil filling stratum 1 after installation is completed, care needs to be taken to enable the measuring rod 70 to have a certain distance with the inner side wall and the inner bottom wall of the sliding groove 311, and the upper port of the first sleeve 32 needs to be located above the soil filling 1, so that accuracy of settlement value measurement is not affected.

In a possible implementation manner, the protection tube 30 and the displacement measuring element 20 are structured as shown in fig. 2 to 4, referring to fig. 2 to 4, a plurality of protection tubes 30 and the displacement measuring element 20 are provided, the plurality of protection tubes 30 are sequentially and threadedly connected from top to bottom, the bottom sealing tube 40 is connected with the lowermost protection tube 30, each protection tube 30 is slidably fitted with a measuring rod 70, and the plurality of displacement measuring elements 20 are correspondingly connected with the plurality of measuring rods 70.

Specifically, a plurality of displacement measuring elements 20 are connected with a plurality of measuring rods 70 in a one-to-one correspondence manner, so that settlement monitoring can be performed on the filled earth strata 1 with different depths, and the practicability is improved.

When mounted, the wires 211 of each displacement measuring element 20 are connected to the corresponding measuring rod 70, and all the wires 211 are penetrated from the upper port of the uppermost protective tube 30. For example, when two protection pipes 30 and two displacement measuring elements 20 are provided, one protection pipe 30 is screwed to the lower end of the other protection pipe 30, the measuring line 211 of one displacement measuring element 20 is connected to the measuring rod 70 located above, the measuring line 211 of the other displacement measuring element 20 is deviated from the measuring rod 70 located above and is connected to the measuring rod 70 located below, and the bottom sealing pipe 40 is screwed to the lower end of the lower protection pipe 30 and is finally buried in the earthen fill formation 1, so that the subsidence monitoring can be simultaneously performed on the earthen fill formations 1 of different depths.

In some embodiments, the projections of two adjacent measuring bars 70 on the horizontal plane form an included angle.

Specifically, the purpose that the projections of two adjacent measuring bars 70 on the horizontal plane form an included angle is to connect the measuring line 211 with the corresponding measuring bar 70, so that the remaining measuring bars 70 can be avoided, and the interference between the measuring line 211 and the remaining measuring bars 70 is avoided when the measuring device is used.

In a possible implementation manner, the displacement measuring element 20 adopts the structure shown in fig. 1 to 4, and referring to fig. 1 to 4, the displacement measuring element 20 includes two displacement sensors 21, a terminal of each displacement sensor 21 is connected with a measuring line 211, and the two measuring lines 211 are respectively disposed near two ends of the measuring rod 70.

Specifically, the displacement sensor 21 is fixed on the bracket 10 by a U-shaped bolt, which ensures the stability of the displacement sensor 21. The two displacement sensors 21 can be used for measuring the displacement of the same measuring rod 70 at the same time, and the average value is obtained, so that the accuracy of measuring the sedimentation value is improved.

Optionally, the displacement sensor 21 may be a pull rope displacement sensor, or may be a resistance type pull rod displacement sensor, and when the displacement sensor 21 is a pull rope displacement sensor, the measuring line 211 is connected to the pull rope; when the displacement sensor 21 is a resistance type pull rod displacement sensor, the measuring line 211 is connected with a pull rod thereof.

The principle of a pull-cord type displacement sensor is that the pull-cord type displacement sensor functions to convert mechanical motion into an electrical signal that can be metered, recorded or transmitted. The pull cord displacement sensor is formed by a tensile pull cord wound on a threaded hub which is coupled to a precision rotation sensor. The stay cord type displacement sensor is installed at a fixed position, and the stay cord is tied up on a moving object. The pull rope moves linearly and the moving object moves along the axis aligned. When the movement occurs, the pull rope stretches or contracts, the hub with the threads drives the precision rotation sensor to rotate, and an electric signal proportional to the moving distance of the pull rope is output. The displacement of the moving object can be obtained by measuring the output electric signal.

The principle of the resistance type pull rod displacement sensor is that the resistance type pull rod displacement sensor is installed on a fixed position, and a pull rod is connected to a moving object. The linear motion of the pull rod is aligned with the motion axis of the moving object. When the movement occurs, the pull rod extends or contracts, the resistance value inside the resistance type pull rod displacement sensor changes, so that the change of the physical quantity to be measured is converted into the change of the resistance value corresponding to the change of the physical quantity to be measured, and the change to be measured is reflected after the change passes through the corresponding measuring circuit.

In some embodiments, the bracket 10 is horizontally provided with a mounting plate 11, and the displacement sensor 21 is connected to the bottom surface of the mounting plate 11.

Specifically, displacement sensor 21 passes through the U type bolt fastening on the bottom surface of mounting panel 11, and the level setting of mounting panel 11 makes things convenient for the installation of staff to displacement sensor 21 even displacement sensor 21 all is in on same horizontal plane to avoid influencing the accuracy that the value measured because of the unreasonable condition of mounted position.

In one possible implementation, the bracket 10 is configured as shown in fig. 1 and 2, and referring to fig. 1 and 2, a reel 50 with a spindle extending in a horizontal direction is rotatably connected to the bracket 10, and a measuring wire 211 is wound around the reel 50.

Specifically, the reel 50 can play a role of guiding the measuring line 211, and the reel 50 can make the extending direction of the measuring line 211 parallel to the axis of the protection pipe 30, the measuring rod 70 can smoothly drive the measuring line 211 to slide on the reel 50, and the rolling reel 50 can reduce the resistance force applied when the measuring line 211 moves, so that the accuracy of measuring the settlement value of the filled ground 1 is ensured.

In a possible implementation manner, the protective casing 60 has a structure as shown in fig. 2 and 3, and referring to fig. 2 and 3, the cross section of the protective casing 60 is square.

Specifically, the top surface of the protective casing 60 is horizontal, so that the pressure of the soil filled above the protective casing 60 on the top surface of the protective casing 60 can be increased, that is, the soil filled drives the protective casing 60 to move downwards more easily, and thus the overall measurement result is more accurate.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. Stratum settlement monitoring device for model test, its characterized in that includes:

the protective tube is buried in the land filling layer along the up-down direction, and the lower end of the protective tube is connected with a bottom sealing tube in a threaded manner;

the protective shell is sleeved on the periphery of the protective tube in a sliding manner, and a measuring rod which penetrates through the protective tube along the radial direction and is in sliding fit with the protective tube along the axial direction is arranged in the protective shell;

the bracket is erected above the protection tube and is connected with the concrete floor; and

and the wiring end of the displacement measuring element is connected with a measuring line connected with the measuring rod, and the measuring line can move up and down along with the measuring rod.

2. The formation settlement monitoring device for model testing of claim 1, wherein the protection pipe comprises:

the first sleeve is sleeved on the periphery of the measuring line; and

the measuring rod is connected with the lower end of the first sleeve in a sliding mode, the measuring rod is connected with the lower end of the second sleeve in a sliding mode, the lower end of the first sleeve is sleeved with the second sleeve in a threaded mode, a sliding groove which extends to the upper edge of the second sleeve along the axial direction of the second sleeve penetrates through the peripheral wall of the second sleeve, the protective shell is sleeved on the peripheries of the first sleeve and the second sleeve in a sliding mode, and the measuring rod is connected into the sliding groove in a sliding mode.

3. The formation settlement monitoring device for model test as claimed in claim 2, wherein the sliding grooves are symmetrically provided in two on the circumferential wall of the second sleeve, and both ends of the measuring rod extend to the outside of the two sliding grooves, respectively.

4. The formation settlement monitoring device for model test as claimed in claim 1, wherein the two opposite side walls of the protective shell are symmetrically provided with threaded holes, and the measuring rod is in threaded connection with the threaded holes.

5. The formation settlement monitoring device for model test as claimed in claim 1, wherein a plurality of the protection tubes and the displacement measuring elements are provided, the plurality of the protection tubes are sequentially screwed from top to bottom, the bottom-sealed tube is connected to the lowermost protection tube, each protection tube has a measuring rod slidably fitted thereon, and the plurality of the displacement measuring elements are connected to the plurality of measuring rods in a one-to-one correspondence.

6. The device for monitoring the subsidence of the stratum for the model test as claimed in claim 5, wherein the projections of two adjacent measuring bars on the horizontal plane are arranged in an included angle.

7. The formation settlement monitoring device for model test as claimed in claim 1, wherein the displacement measuring element comprises two displacement sensors, one of the measuring lines is connected to a terminal of each of the displacement sensors, and the two measuring lines are respectively disposed near both ends of the measuring rod.

8. The apparatus for monitoring the subsidence of ground for model test as claimed in claim 7, wherein a mounting plate is horizontally provided on the bracket, and the displacement sensor is connected to the bottom surface of the mounting plate.

9. The formation settlement monitoring device for model test as claimed in claim 1, wherein a reel having a main shaft extending in a horizontal direction is rotatably connected to the bracket, and the measuring wire is wound around the reel.

10. The formation settlement monitoring device for model test of claim 1, wherein the protective shell has a square cross-section.

Images