CN106441060A - Displacement monitoring device and method for arch circumference of tunnel slip-casting model test - Google Patents

Abstract

The invention discloses a device and method for monitoring arch circumference displacement in tunnel grouting model tests, comprising a resistance strain type single point displacement gauge, a rigid measuring line and a data acquisition device, wherein the resistance strain type single point displacement gauge is fixed On the bottom plate of the tunnel excavation model; one end of the rigid measuring line is connected with the measuring rod of the resistance strain type single-point displacement meter, and the other end is fixed on the arch circumference displacement measuring point of the tunnel excavating model, so that the rigid measuring line and the The measuring rods are on the same straight line and perpendicular to the cut surface at the corresponding measuring point; the resistance strain type single point displacement gauge is connected with the data collection device through the data transmission line. The rigid measuring line in the present invention is fixed on the measuring point, which can accurately measure the continuous displacement of the measuring point, and overcomes the problem that in the traditional monitoring method, the measuring point cannot be fixed. The downside of inaccuracy.

Description

Device and method for monitoring arch circumference displacement in tunnel grouting model test

technical field

The invention relates to a device and a method for monitoring arch circumference displacement in tunnel grouting model tests.

Background technique

In recent years, with my country's vigorous development of underground engineering construction, my country has become the world's largest country in the scale and speed of tunnel and underground engineering construction. Different problems will be encountered in the process of underground engineering construction, among which water and mud inrush disasters have become one of the main disasters in underground engineering construction, seriously affecting the construction progress, causing huge casualties and economic losses. At present, the most important and effective method for controlling water and mud inrush disasters is the grouting method, which can effectively control water and mud inrush disasters, and play the role of water blocking and reinforcement. The grouting method has been widely used in engineering practice, but because the development of grouting theory is still far behind the engineering practice, the grouting technology is far from mature due to the lack of effective theoretical guidance. The grouting model test method can simulate complex geological structures more comprehensively and truly, and provide a basis for establishing new theories and mathematical models. It is an important means of researching grouting theory. In the tunnel grouting model test, the collection of arch circumference displacement plays a key role in analyzing the influence of grouting on the deformation of surrounding rock and evaluating the stability of surrounding rock. How to effectively monitor and collect arch circumference displacement in model tests is a research hotspot with difficulty. In the tunnel model test, the monitoring measurement and data collection of the displacement of the arch circumference during the simulated excavation are important contents in the test process. However, different from the tunnel engineering site, there are the following problems in the arch circumference displacement monitoring in the model test: the space is narrow, and the operation is inconvenient; the engineering convergence ruler and displacement gauge are too large for the model test; The fixed-point measurement method is susceptible to interference, and the measured displacement is discontinuous, and the data is limited. At present, in the tunnel model test, the displacement measurement methods of the rock around the arch mainly include: calibrate the contour of the tunnel before and after excavation on the model box, and calculate the deformation of the tunnel by comparing the contour before and after the tunnel; The instrument measures the length of several measuring lines on the tunnel section and compares the design length of the lining to calculate the deformation, etc. However, the existing methods all have the disadvantages that the measuring points cannot be accurately fixed, the measurement accuracy is low, the simultaneous measurement of the vault sinking and the surrounding convergence cannot be realized, and the real-time collection of deformation data during the excavation process cannot be realized.

Contents of the invention

In view of the above-mentioned problems existing in the prior art, an object of the present invention is to provide a single-point monitoring device for the arch circumferential displacement of the tunnel grouting model test. The monitoring device has high measurement accuracy, small size, easy operation, and Narrow space limitation, can realize displacement continuity detection and other advantages.

The second object of the present invention is to provide a displacement monitoring system for tunnel grouting model tests, the device can realize accurate monitoring of multiple points in the arch circumference, and monitor the displacement of the arch circumference through multi-point displacement monitoring.

The third object of the present invention is to provide a method for monitoring arch circumference displacement in tunnel grouting model tests. Using the above-mentioned device for monitoring, accurate measurement of arch circumference displacement can be realized.

In order to achieve the above object, the present invention adopts the following technical solutions:

A single-point monitoring device for tunnel grouting model test arch perimeter displacement, comprising a resistance strain type single point displacement meter, a rigid measuring line and a data acquisition device, wherein the resistance strain type single point displacement meter is fixed at the tunnel excavation the bottom plate of the model;

One end of the rigid measuring line is connected to the measuring rod of the resistance strain type single-point displacement meter, and the other end is fixed on the arch circumference displacement measuring point of the tunnel excavation model, so that the rigid measuring line is on the same straight line as the measuring rod and The tangent plane at the corresponding measuring point is vertical;

The resistance strain type single-point displacement gauge is connected with the data collection device through the data transmission line.

The arch circumference displacement measuring point is the monitoring point used to monitor the arch circumference displacement, and the displacement of the arch circumference is determined by measuring the displacement of the monitoring point.

Rigid measuring line refers to the measuring line with hard texture and not easy to deform. The single-point displacement meter is fixed on the fixed base, and its position has been fixed. One end of the rigid measuring line is connected with the single-point displacement meter, that is, the position of this end of the rigid measuring line is fixed; Point, that is, the end will have a corresponding displacement with the displacement of the arch circumference of the tunnel grouting model. Since the rigid measuring line will not be deformed, the resistance strain type single-point displacement gauge is deformed under the tension of the rigid measuring line. The deformation is the displacement of the arch circumference, and the direct reflection of the deformation is the resistance change. , and the amount of resistance change can be detected by the data collection device.

Because one end of the rigid measuring line is fixed on the arch circumference displacement measuring point, that is, the measuring point is accurately determined, and the measuring line is a rigid measuring line, basically no deformation occurs, so the accurate measurement of the arch circumference displacement can be realized.

Preferably, one end of the resistance strain type single-point displacement gauge is buried in the bottom plate of the tunnel grouting model, the other end is located outside the bottom plate, and the measuring rod located outside the bottom plate is connected to the rigid measuring line, so that the measuring rod is connected to the rigid measuring line. Rigid survey lines are on the same straight line.

Further preferably, the length of the part of the resistance strain type single-point displacement gauge embedded in the bottom plate of the tunnel grouting model is half of the total length. The purpose of burying half of the resistance strain type single-point displacement gauge is to facilitate unification and improve the unity of construction.

Preferably, it also includes a fixed base, the fixed base includes a fixed plate and a connecting piece, the fixed plate and one end of the connecting piece are generally vertically arranged, and the other end of the connecting piece is embedded in the bottom plate of the tunnel grouting model to fix the fixed base .

Further preferably, a through-hole or a through-slot is opened on the fixed plate, the resistance strain type single-point displacement gauge is fixed in the hole or the through-slot, and a set distance is reserved between the through-hole and the periphery of the fixed plate.

The fixed base can fix the resistance strain single-point displacement gauge to prevent the movement of the displacement gauge. There is a set distance between the through hole on the fixed plate and the periphery of the fixed plate. The base is inclined. At this time, the periphery of the fixed plate can be in contact with the bottom plate or partially buried in the bottom plate to play a supporting role and prevent the inclination direction of the resistance strain type single-point displacement gauge from changing.

Preferably, the rigid measuring line is a thin steel wire rope.

Thin steel wire rope is not only not easily deformed, but also has high strength and is not easy to break, so it is suitable for use in environments with high tensile stress.

A system for monitoring arch circumference displacement in tunnel grouting model tests, comprising at least two groups of single-point arch circumference displacement monitoring devices, each of which includes a resistance strain type single point displacement meter and a rigid measuring line, the resistance strain type single point The displacement gauge is fixed on the bottom plate of the tunnel grouting model; one end of the rigid measuring line is connected to the measuring rod of the resistance strain type single point displacement gauge, and the other end is fixed on the arch circumference displacement measuring point of the tunnel grouting model;

The measuring rods of the resistance strain type single point displacement gauges in each group of single point arch circumference displacement monitoring devices are on the same straight line as the rigid measuring line, and are perpendicular to the tangent plane where the corresponding measuring points are located. All the resistance strain type single point displacement gauges All are connected with the data acquisition device, and all the resistance strain type single-point displacement gauges are connected with the data acquisition device.

Simultaneous monitoring of multi-point displacement can be realized, and the arch circumference displacement of the tunnel grouting model can be monitored more accurately.

Preferably, a group of single-point arch perimeter displacement monitoring devices are arranged vertically, the resistance strain type single-point displacement gauge is fixed in the middle of the bottom plate, and one end of the rigid measuring line is fixed on the vault to monitor the displacement of the vault.

The resistance strain type single-point displacement gauge is fixed in the middle of the bottom plate, and the rigid measuring line is fixed on the vault. At this time, the displacement gauge and the rigid measuring line are both vertically set, which can accurately monitor the displacement of the vault.

Further preferably, the number of groups of single-point circumferential displacement monitoring devices is an odd number, wherein one group is vertically arranged, and the other groups are obliquely arranged, so that the fixed position of the resistance strain type single-point displacement gauge and the fixed position of the rigid measuring line in each group Points are located on either side of a vertically set rigid survey line.

A method for monitoring arch circumference displacement in a tunnel grouting model test, comprising the following steps:

1) Determine the position of the arch circumference displacement monitoring measuring point of the tunnel grouting model;

At the same section of the tunnel grouting model, according to the number of measuring points to be determined, the arch circumference section can be averaged, and each split point is used as a measuring point. This method is relatively easy to implement.

One end of the rigid measuring line is fixed at the position of the measuring point, and the rigid measuring line can be fixed by rivets. Straighten the rigid measuring line so that the rigid measuring line is perpendicular to the tangent plane at the corresponding measuring point, and determine the inclination angle of the rigid measuring line. Location;

2) Drill and excavate the fixed position of the resistance strain type single point displacement gauge, insert the resistance strain type displacement gauge into the fixed base, put the two into the drill hole, and adjust the measuring rod and rigidity of the resistance strain type displacement gauge The measuring line is on the same straight line and perpendicular to the cut surface at the corresponding measuring point. After adjustment, landfill and compact;

3) Repeat the above steps to install multiple groups of single-point arch circumference displacement monitoring devices to realize simultaneous monitoring of multi-point arch circumference displacement.

4) With the simulated excavation of the tunnel grouting model test, the single-point arch circumference displacement monitoring device will continuously monitor the change of displacement, and transmit the change of arch circumference displacement to the data acquisition device through the data transmission line, and the data acquisition device will store the displacement Change data and draw the displacement change curve synchronously.

The beneficial effects of the present invention are:

1. The rigid measuring line in the present invention is fixed on the measuring point, and the continuous displacement of the measuring point can be accurately measured, which overcomes the fact that in the traditional monitoring method, the measuring point cannot be fixed, and the measuring point deviates during the displacement process of the arch circumference. resulting in inaccurate measurements.

2. In the present invention, the position of the resistance strain displacement gauge is fixed, the displacement gauge is connected to the rigid measuring line, and the rigid measuring line is fixedly connected to the measuring point. When the arch circumference is displaced, the corresponding displacement can occur through the rigid measuring line. Furthermore, the displacement meter is used for measurement, which can realize continuous real-time displacement monitoring of each measuring point.

3. By setting multiple sets of single-point arch circumference displacement monitoring devices, the simultaneous monitoring of multi-point arch circumference displacement can be realized, that is, the simultaneous measurement of vault sinking and peripheral convergence can be realized, and the displacement changes during tunnel excavation can be more comprehensively monitored.

4. The device used in the present invention is small in size, not limited by a narrow space, easy to install and operate, and suitable for tunnel grouting model tests.

5. The data acquisition device can realize the real-time collection of displacement data changes, and can draw the displacement change curve in real time to visualize the displacement of the arch circumference.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of a single-point circumferential displacement monitoring device of the present invention;

Fig. 2 is a schematic diagram of the overall structure of the multi-point arch circumference displacement monitoring device of the present invention.

Among them, 1. Resistance strain type single-point displacement gauge, 2. Rigid measuring line, 3. Fixed base, 4. Rivet, 5. Data transmission line, 6. Data acquisition device.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Tunnel grouting model is a model for simulating tunnel grouting. Tunnel grouting is to inject some curable grout into the cracks or gaps in the rock and soil of the tunnel with an appropriate method, through replacement, filling, extrusion, etc. A method for improving the physical and mechanical properties of tunnels. The shape of the cross section of the tunnel grouting model is also arched similar to the tunnel. The tunnel grouting model also includes an arch structure and a bottom plate, and the bottom plate is located below the arch structure, which is equivalent to the road in the tunnel. The surface of the bottom plate here is preferably flat, that is, there are no potholes on the surface, which belongs to an idealized test model. But in fact, there is no special requirement for the specific shape of the bottom plate surface, as long as it meets the requirements of the tunnel grouting model obtained by matching with the arched tunnel model.

Example 1

As shown in Figure 1, a single-point monitoring device for tunnel grouting model test arch circumferential displacement, including a resistance strain type single-point displacement meter 1, a rigid measuring line 2, a fixed base 3 and a data acquisition device 6, wherein the The fixed base 3 is fixed on the bottom plate of the tunnel grouting model, and the resistance strain type single-point displacement gauge 1 is fixed on the fixed base 3;

One end of the rigid measuring line 2 is connected to the resistance strain type single-point displacement meter 1, and the other end is fixed on the arch circumference displacement measuring point of the tunnel grouting model;

The resistance strain type single-point displacement gauge 1 is connected with the data collection device 6 through the data transmission line 5 .

The arch circumference displacement measuring point is the monitoring point used to monitor the arch circumference displacement, and the displacement of the arch circumference is determined by measuring the displacement of the monitoring point.

Rigid measuring line 2 refers to the measuring line that is hard and not easily deformed, that is, the measuring line that does not undergo elastic deformation. This is only an ideal situation, because any material will deform under the action of tension or pressure. The elastic deformation of the line during use is negligible compared to the displacement of the arch circumference, so the line can be called a rigid line. When measuring the displacement of the arch circumference, the rigid measuring line 2 will be subjected to a large force. In order to meet the actual work needs, that is, the rigid measuring line 2 will still maintain the original state under the action of a large tensile force without breaking. For the purpose of real-time monitoring, this requires that the rigid measuring line 2 has sufficient strength, and the strength is the lower limit of the maximum tensile force that the rigid measuring line 2 receives during the monitoring process.

The resistance strain type single-point displacement meter 1 is composed of a measuring rod, a protective tube, a sliding resistor, etc. The measured structure is connected to the measuring rod. The mechanism is transmitted to the sliding resistor, and the sliding resistor converts the displacement physical quantity into an electrical signal quantity, which is transmitted to the data acquisition device 6 through the data transmission line 5, and the displacement change of the measured structure can be measured.

The single-point displacement meter is used to monitor the displacement of a certain measuring point, and there is no substantial difference from the name of the traditional displacement meter, because the displacement of the measured structure is measured at a certain point in the measured structure , the relative amount before and after its displacement, this is in an ideal state, that is, each point in the measured structure is translated along the displacement direction of the monitoring point with the same displacement, and the displacement of a monitoring point can be obtained The overall displacement ignores the difference in the displacement of each point of the measured structure itself.

Since the grouting of the tunnel grouting model is not the overall grouting but partial grouting during the grouting process, the displacement of the arch circumference at different positions of the arch structure of the tunnel grouting model will change differently, which cannot be used The displacement of one point represents the displacement of the whole. Therefore, based on experience, the cross-section of the arch structure can be roughly divided into areas around the arch. A certain range with basically the same displacement can be regarded as a region. One point is selected as the measuring point. Therefore, since there are many parts with different displacements around the arch circumference, it is necessary to monitor multiple measuring points. It is also possible to determine multiple measuring points in a small area, and obtain an approximate displacement by measuring the displacement of multiple measuring points and calculating the average value.

The resistance strain type single-point displacement meter 1 is fixed on the fixed base 3, and its position has been fixed. One end of the rigid measuring line 2 is connected with the measuring rod of the resistance strain type single-point displacement meter 1. When the rigid measuring line 2 is displaced, it will drive the displacement The measuring rod of the meter has a corresponding displacement, and the other end is fixed on the arch circumference displacement measuring point of the tunnel grouting model, that is, the end will have a corresponding displacement along with the displacement of the arch circumference of the tunnel grouting model. Since the rigid measuring line 2 will not undergo elastic deformation, the measuring rod of the resistance strain type single-point displacement meter 1 will be displaced under the tension of the rigid measuring line 2, which will be transmitted to the sliding resistor through the conversion mechanism. The displacement physical quantity is converted into an electrical signal quantity, which is the arch circumference displacement. The electrical signal is transmitted to the data acquisition device 6 through the data transmission line 5, and the arch circumference displacement is read out, and the corresponding displacement curve is drawn.

Since one end of the rigid measuring line 1 is fixed on the arch circumference displacement measuring point, when the arch circumference is displaced, the displacement of the measuring point directly reflects the displacement of the point around the arch, and the displacement of the measuring point roughly reflects the displacement in a certain area. arch circumference displacement. When the measuring point is displaced, under the constraints of other structures of the tunnel model, the displacement direction of the measuring point is generally along the direction perpendicular to the tangent direction of the measuring point at the arch circumference. Since the displacement of the arch circumference will not be too large, the influence on the elevation angle of the rigid measuring line 2 can be ignored, that is, it can be understood that the displacement direction of the measuring point is the direction along the extension of the rigid measuring line 2, so the displacement distance That is the moving distance of the rigid measuring line 2, that is, the moving distance of the measuring rod. Therefore, the measurement at this time is accurate.

As a preferred solution, the bottom end of the resistive single-point displacement gauge 1 is buried in the bottom plate of the tunnel grouting model, the end with the measuring rod is located outside the bottom plate, and the measuring rod is connected to the rigid measuring line 2 .

The length of the part of the resistance strain type single-point displacement gauge 1 embedded in the bottom plate of the tunnel grouting model is half of the total length.

The resistance strain type single-point displacement gauge 1 is buried in the bottom plate of the tunnel grouting model to fix the displacement gauge. The embedding half here is not a mandatory requirement, but it is convenient for construction and unified construction under the premise of ensuring the fixed strength of the displacement gauge. standard.

The function of the fixed base 3 here is only to fix the resistance strain type single-point displacement meter 1. In the actual measurement process, it is necessary to require the measuring rod of the resistance strain type single-point displacement meter 1 and the rigid measuring line 2 to be on the same straight line. And the direction of the straight line is perpendicular to the tangent plane at the position of the measuring point, so as to ensure the accuracy of the measurement. If only the resistance strain type single-point displacement gauge 1 is buried on the bottom plate of the tunnel grouting model, the displacement gauge will be shifted under the tension of the rigid measuring line 2, or even not firmly fixed, and it will be pulled out, resulting in failure of monitoring .

As a preferred embodiment, the fixed base 3 includes a fixed plate and a connecting piece, the fixed plate is a plate-shaped structure, and the connecting piece can be a plate-shaped structure or a rod-shaped structure. The connecting piece is arranged vertically to the fixed plate, and a through groove is opened on the fixed plate, the resistance strain displacement gauge 1 is inserted into the through groove, and the lower end of the displacement gauge is buried in the bottom plate.

According to the direction of the cut surface at the corresponding measuring point, determine the direction of the rigid measuring line 2, and then determine the embedding point of the resistance strain displacement gauge 1, and insert the displacement gauge into the through groove of the fixed plate so that the outer surface of the displacement gauge is in contact with the fixed base. The surface of the connecting piece 3 is attached to the surface, and the inclination direction of the displacement meter and the fixed base 3 is adjusted so that the measuring rod in the displacement meter is on the same straight line as the rigid measuring line, and is perpendicular to the cut plane at the measuring point. Keep the inclination direction and position of the fixed base 3 and the displacement gauge unchanged, and bury the fixed base 3 and the displacement gauge. Since there is still a certain distance between the through groove on the fixed plate of the fixed base 3 and the periphery of the fixed plate, the fixed base 3 is arranged obliquely, preferably one side of the fixed plate is also contacted with the base plate, or a part of the fixed plate is buried in the base , the part in contact with the bottom plate plays a role in supporting the fixed plate, which is helpful to maintain the set inclination angle of the resistance strain type single point displacement gauge, and can also prevent the resistance strain type single point displacement gauge from slipping.

As a preferred manner, the rigid measuring line 2 is a thin steel wire rope. Thin steel wire rope is not only not easily deformed, but also has high strength and is not easy to break, so it is suitable for use in environments with high tensile stress. The rigid measuring line can also be made of other materials, but it should meet the characteristics of being hard, having high strength, and not easily deformed.

Example 2

As shown in Figure 2, a monitoring system for arch circumference displacement in tunnel grouting model tests includes at least two groups of single-point arch circumference displacement monitoring devices, each of which includes a resistance strain type single-point displacement meter 1 and a rigid measuring line 2 and a fixed base 3, the fixed base 3 is fixed on the bottom plate of the tunnel grouting model, and the resistance strain type single point displacement gauge 1 is fixed on the fixed base 3; one end of the rigid measuring line 2 is connected with the resistance strain type single point displacement gauge 1 The measuring rod is connected, and the other end is fixed on the arch circumference displacement measuring point of the tunnel grouting model;

The measuring rod of the resistance strain type single point displacement gauge 1 and the rigid measuring line 2 in each group of single point arch circumference displacement monitoring devices are on the same straight line and perpendicular to the tangent plane where the corresponding measuring point is located. All the resistance strain type single point displacement gauges The displacement gauges are all connected with the data acquisition device. The principle here is the same as that in Embodiment 1, in order to ensure accurate monitoring of the displacement of each measuring point.

Among them, a group of single-point arch circumference displacement monitoring devices are installed vertically. The resistance strain single-point displacement gauge 1 is fixed on the middle of the bottom plate, and one end of the rigid measuring line 2 is fixed on the vault. At this time, the resistance strain type single-point displacement gauge The measuring rod of 1 and the rigid measuring line 2 are all set vertically, which can be used to monitor the displacement of the vault.

The number of groups of single-point arch circumference displacement monitoring devices is an odd number, one group is set vertically, and the other group is set obliquely, so that the fixed position of the resistance strain type single-point displacement meter and the fixed point of the rigid measuring line in each group are located in the vertical direction. Set both sides of the rigid survey line.

Each group of single-point arch circumference displacement measurement devices is roughly symmetrically arranged, which can more comprehensively analyze the displacement of the arch circumference, and can compare the difference in displacement on both sides of the arch circumference to further analyze the impact of grouting on the arch circumference.

A method for monitoring arch circumference displacement in a tunnel grouting model test, comprising the following steps:

1) Determine the arch perimeter displacement monitoring measuring point of the tunnel grouting model and the fixed position of the resistance strain type single-point displacement gauge 1 on the bottom plate;

At the same section of the tunnel grouting model, according to the number of measuring points to be determined, the arch circumference section can be averaged, and each split point is used as a measuring point. This method is relatively easy to implement.

One end of the rigid measuring line 2 is fixed at the position of the measuring point, and the rigid measuring line 2 can be fixed by a rivet. Straighten the rigid measuring line 2 so that the rigid measuring line 2 is perpendicular to the cut surface at the corresponding measuring point, and determine the inclination angle of the rigid measuring line 2. The contact point between the rigid measuring line 2 and the bottom plate is the resistance strain type single-point displacement gauge 1 fixed position on the base plate.

2) Drill and excavate the fixed position of the resistance strain type single-point displacement gauge 1, insert the resistance strain type displacement gauge 1 into the fixed base 3, put both into the drill hole, and adjust the resistance strain type displacement gauge 1 The measuring rod is on the same straight line as the rigid measuring line 2, and is perpendicular to the cut surface at the corresponding measuring point. After adjustment, landfill and compaction are carried out.

3) Repeat the above steps to install multiple groups of single-point arch circumference displacement monitoring devices to realize simultaneous monitoring of multi-point arch circumference displacement.

4) With the simulated excavation of the tunnel grouting model test, the single-point arch circumference displacement monitoring device will continuously monitor the change of displacement, and transmit the change of arch circumference displacement to the data acquisition device through the data transmission line, and the data acquisition device will store the displacement Change data and draw the displacement change curve synchronously.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the scope of protection of the invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (10)

1. a kind of for tunnel grouting model test arch Zhou Weiyi single-point monitoring device it is characterised in that：Including resistance-strain type Single point extensometer, rigid survey line data harvester, wherein, described resistance-strain type single point extensometer is fixed on tunnel excavation On the base plate of model；

One end of rigid survey line is connected with the measuring staff of resistance-strain type single point extensometer, and the other end is fixed on tunnel excavation model On all displacement measuring points of arch, make rigid survey line with described measuring staff on the same line, and vertical with the tangent plane at corresponding measuring point；

Resistance-strain type single point extensometer is connected with transacter by data line.

2. according to claim 1 for tunnel grouting model test encircle Zhou Weiyi single-point monitoring device it is characterised in that： One end of described resistance-strain type single point extensometer is embedded in the base plate of tunnel grouting model, and the other end is located at base plate external, Be connected with described rigid survey line positioned at the measuring staff of base plate external so that described measuring staff with rigid survey line on the same line.

3. according to claim 2 for tunnel grouting model test encircle Zhou Weiyi single-point monitoring device it is characterised in that： The length that described resistance-strain type single point extensometer imbeds the part in tunnel excavation pattern board is the half of total length.

4. according to claim 1 for tunnel grouting model test encircle Zhou Weiyi single-point monitoring device it is characterised in that： Also include firm banking, described firm banking includes fixed plate and connector, fixed plate is generally vertically set with one end of connector Put, firm banking is fixed by way of imbedding tunnel excavation pattern board by the other end of connector.

5. according to claim 4 for tunnel grouting model test encircle Zhou Weiyi single-point monitoring device it is characterised in that： Through hole is opened up, described resistance-strain type single point extensometer is fixed in this through hole, described through hole and fixed plate in described fixed plate Periphery reserve setpoint distance.

6. according to claim 1 for tunnel grouting model test encircle Zhou Weiyi single-point monitoring device it is characterised in that： Described rigid survey line is seizing wire.

7. a kind of for all system for monitoring displacement of tunnel grouting model test arch it is characterised in that：Encircle including at least two groups of single-points All displacement monitors, every group all includes resistance-strain type single point extensometer and rigid survey line, described resistance-strain type single-point position Move meter to be fixed on the base plate of tunnel grouting model；One end of rigid survey line is connected with the measuring staff of resistance-strain type single point extensometer Connect, the other end is fixed on all displacement measuring points of arch of tunnel grouting model；

The measuring staff of resistance-strain type single point extensometer in all displacement monitors of every group of single-point arch and rigid survey line are with always On line and vertical with the tangent plane of corresponding measuring point position, all of resistance-strain type single point extensometer is all filled with data acquisition Put connection, all of resistance-strain type single point extensometer is all connected with data acquisition unit.

8. according to claim 7 encircle all system for monitoring displacement for tunnel grouting model test it is characterised in that：Wherein The all displacement monitors of one group of single-point arch are vertically arranged, and resistance-strain type single point extensometer is fixed on the middle part of base plate, and rigidity is surveyed One end of line is fixed on vault, the displacement of monitoring vault.

9. according to claim 8 encircle all system for monitoring displacement for tunnel grouting model test it is characterised in that：Single-point The group number of all displacement monitors of arch is odd number, and one of which is vertically arranged, and other groups are obliquely installed, and so that the resistance in every group is answered The fixing point of the fixed position of variant single point extensometer and rigid survey line is located at the both sides of vertically arranged rigid survey line.

10. a kind of for all displacement monitoring methods of tunnel grouting model test arch it is characterised in that：Comprise the steps：

1) determine the arch week displacement monitoring point position of tunnel grouting model, in one end of the position of measuring point fixing rigidity survey line, Stretch rigid survey line, make rigid survey line vertical with the tangent plane at corresponding measuring point, now rigid survey line with the contact point of base plate is For fixed position on base plate for the resistance-strain type single point extensometer；

2) hole in resistance-strain type single point extensometer fixed position and excavate, resistance-strain type displacement meter is inserted firm banking In, and both are put in boring, adjust the measuring staff of resistance-strain type displacement meter with rigid survey line on the same line, and with phase Answer the tangent plane at measuring point vertical, filled and tamp；

3) repeat above step, all displacement monitors of setting multigroup single-point arch, realize monitoring while multiple spot arch Zhou Weiyi.

4) with the excavation simulation of tunnel grouting model test, all displacement monitors of single-point arch can constantly monitor the change of displacement Change, and the change of arch Zhou Weiyi is transmitted to data acquisition unit by data line, data acquisition unit can store displacement Variable quantity data is simultaneously synchronous to draw displacement changing curve.