CN113431016A - Soft rock large deformation section tunnel shallow-buried underground surface-penetrating building surface monitoring method - Google Patents

Abstract

The invention relates to the technical field of tunnel construction, in particular to a method for monitoring the earth surface of a building with a soft rock large deformation section, which passes through the earth surface under a shallow tunnel, and comprises the following steps; in-hole observation and out-of-hole observation; the observation in the hole comprises digging surface observation and operated section observation; hole appearance inspection includes observation of ground buildings; measuring the surface settlement and the building settlement; setting a ground surface settlement observation point before tunnel excavation; the distance from the center line of the tunnel to the farthest ground surface settlement observation point is greater than or equal to the sum of the tunnel burial depth and the tunnel excavation width; vault subsidence measurement and clearance change measurement; determining the section spacing according to the surrounding rock level; and (4) distributing points according to an excavation method, wherein the height of the points is higher than that of each step, the reflection sheet of the measuring point is aligned to the direction of the hole, and the measuring point exposes the initial supporting surface. Through reasonable section arrangement, earth surface monitoring and earth surface building monitoring are increased, so that the monitoring data are more accurate and reliable, and the purposes of controlling settlement and accelerating construction are achieved.

Description

Soft rock large deformation section tunnel shallow-buried underground surface-penetrating building surface monitoring method

Technical Field

The invention relates to the technical field of tunnel construction, in particular to a method for monitoring the surface of a building with a soft rock large deformation section, a shallow tunnel and a downward through surface.

Background

Xigeda stratum is soft in rock quality and easy to weather, can disintegrate in water, has poor water stability and more steep dip joints, and is frequently broken off at the top and the wall of a cave, so that the collapse and even top collapse are caused.

In tunnel excavation construction, the rock mass is disturbed, the rock mass balance is broken, the internal force is redistributed, elastic-plastic deformation, compression and creep deformation are generated, the surrounding rock moves and then extends to the lower part of the ground surface of the existing building foundation and is transmitted to the building through the foundation, so that the existing building structure and the foundation generate secondary internal force and deformation, the safe use of the existing building is limited, and the existing building loses stability and is damaged in severe cases.

In the tunnel construction process, the traditional method only monitors in a hole or only monitors the ground surface. Because rock mass around the tunnel varies greatly, the external force applied to the tunnel is uncertain; the traditional monitoring method cannot accurately master the stress condition of the device.

Disclosure of Invention

The invention aims to: aiming at the problem that the stress condition of a delay body around a tunnel cannot be accurately mastered in the prior art, the method for monitoring the surface of the building penetrating through the surface under shallow burying of the tunnel at the large deformation section of soft rock is provided. The monitoring method is based on conventional monitoring measurement in a tunnel construction hole, increases earth surface monitoring and earth surface building monitoring through reasonable section arrangement, and can dynamically adjust tunnel construction and supporting parameters by utilizing monitoring data so as to achieve the purposes of controlling settlement and accelerating construction.

In order to achieve the purpose, the invention adopts the technical scheme that:

a monitoring and measuring method for a tunnel shallow buried underground ground surface building comprises the following steps;

in-hole observation and out-of-hole observation;

the observation in the hole comprises digging surface observation and operated section observation; hole appearance inspection includes observation of ground buildings;

measuring the surface settlement and the building settlement;

setting surface settlement observation points at a transverse interval of 2-5m before tunnel excavation, and encrypting measurement points around the center line of the tunnel; the distance from the center line of the tunnel to the farthest ground surface settlement observation point is greater than or equal to the sum of the tunnel burial depth and the tunnel excavation width; the number of observation points per section is more than 7;

vault subsidence measurement and clearance change measurement;

determining the section spacing according to the surrounding rock level; and (4) distributing points according to an excavation method, wherein the distribution height is higher than each step, the reflection sheet of the measuring point is aligned to the direction of the opening of the hole, and the length of the exposed primary support surface of the measuring point is less than or equal to 5 cm.

The monitoring method is based on conventional monitoring measurement in a tunnel construction hole, increases earth surface monitoring and earth surface building monitoring through reasonable section arrangement, and can dynamically adjust tunnel construction and supporting parameters by utilizing monitoring data so as to achieve the purposes of controlling settlement and accelerating construction.

The preferable scheme of the invention is that at least two ground surface settlement measuring base points are arranged, and the ground surface settlement measuring base points are buried in the areas which are 3-5 times of the outer diameter of the hole in the longitudinal direction and the transverse direction of the tunnel excavation and are within the range influenced by the ground surface settlement.

At least two base points are buried, so that the correction is more convenient, all the base points and the surrounding water level points are measured together to obtain approximate elevations, and when a controlled building exists in the earth surface, the measurement range needs to be properly enlarged.

As a preferable scheme of the invention, when the ground surface settlement observation points are arranged, when the ground surface is on the ground, the ground surface settlement observation points are formed by burying reinforcing steel bars in the ground surface, the periphery of the ground surface settlement observation points is filled with concrete, and the depth of the concrete is less than or equal to 30 cm; when the reflector is arranged on a building, the reflector is arranged on the surface of the building for observation.

As a preferred scheme of the invention, the fracture surface spacing in the class III wall rock is less than or equal to 30 m; the interval between the IV-grade surrounding rock sections is less than or equal to 10m, the interval between the V-grade surrounding rock sections is less than or equal to 5m, and the dangerous sections are properly encrypted.

As a preferred scheme of the invention, the measuring point in the hole is driven into a rock stratum by using a reinforcing steel bar after the excavation is finished, the driving distance is more than 15cm, the reinforcing steel bar is exposed out of the concrete surface of the primary support and is less than or equal to 5cm, the outer leakage end is provided with a hook, an iron sheet is welded on the hook, and finally, a reflector is attached to the iron sheet, wherein the reflector faces to the hole.

As a preferred embodiment of the present invention, the surface subsidence measurement, the vault subsidence measurement and the clearance change measurement are performed on the same cross section.

As a preferred embodiment of the present invention, the surface subsidence measurement, the vault subsidence measurement, and the clearance change measurement are performed by using a total station.

As a preferred scheme of the present invention, the measurement frequency of the surface subsidence measurement, the vault subsidence measurement and the clearance change measurement is the same according to the monitoring measurement frequency determined by the distance from the excavation surface.

As a preferred embodiment of the present invention, the monitoring and measuring time of the surface subsidence measurement, the vault subsidence measurement and the clearance change measurement is continued until the surface subsidence is stable and the secondary lining structure of the tunnel is closed.

As a preferred scheme of the invention, after the original data is collected, the data is sorted and a temporal curve is formed; and (5) performing regression analysis according to the temporal curve to predict the highest value and the change rate of the settlement.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. the invention provides a method for monitoring the earth surface of a building with a large soft rock deformation section tunnel which passes through the earth surface under shallow burying, which uses a monitoring technology combining the tunnel with the earth surface, provides the most direct information for reinforcing the soft surrounding rock tunnel through data acquisition and analysis, and effectively predicts the settlement of the Xigeda stratum tunnel through data, solves the problem of safe and rapid construction of the Xigeda stratum tunnel passing through the earth surface highway and large earth surface structures under the shallow burying section, has obvious positive effect on controlling the construction safety, and ensures the construction safety and quality.

2. According to the method for monitoring the surface of the building with the shallow buried tunnel and the underground ground surface in the large soft rock deformation section, the corresponding monitoring scheme is adopted according to research and judgment of different geology and terrains, the number and the buried sections of monitoring points are actually judged, monitoring data are formed through reasonable frequent monitoring, and the field construction is guided after the monitoring data are sorted and analyzed. The ground surface monitoring technology for the soft rock large deformation section tunnel shallow buried underground ground surface building can effectively control the tunnel settlement and the safety and stability of the ground surface large building by dynamically adjusting the construction parameters through monitoring data.

Drawings

FIG. 1 is a flow chart of the construction process of the monitoring and measuring method of the present invention.

Fig. 2 is a schematic diagram of an arrangement of earth surface settlement observation points according to the monitoring and measuring method of the present invention.

FIG. 3 is a schematic diagram of the arrangement of building settlement measuring points according to the monitoring and measuring method of the present invention.

FIG. 4 is a schematic view of a distribution mode of different development methods of the monitoring and measuring method according to the present invention.

FIG. 5 is a schematic view of a target structure of a reflective sheet according to the monitoring and measuring method of the present invention.

FIG. 6 is a flowchart illustrating engineering safety evaluation of the monitoring and measuring method of the present invention.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

A monitoring and measuring method for a tunnel shallow buried underground ground surface building comprises the following steps;

in-hole observation and out-of-hole observation; the observation in the hole comprises digging surface observation and operated section observation; hole appearance inspection includes observation of ground buildings;

measuring the surface settlement and the building settlement; setting surface settlement observation points at a transverse interval of 2-5m before tunnel excavation, and encrypting measurement points around the center line of the tunnel; the distance from the center line of the tunnel to the farthest ground surface settlement observation point is greater than or equal to the sum of the tunnel burial depth and the tunnel excavation width; the number of observation points per section is more than 7;

vault subsidence measurement and clearance change measurement; determining the section spacing according to the surrounding rock level; and (4) distributing points according to an excavation method, wherein the distribution height is higher than each step, the reflection sheet of the measuring point is aligned to the direction of the opening of the hole, and the length of the exposed primary support surface of the measuring point is less than or equal to 5 cm.

The monitoring measurement items, monitoring methods and measurement instruments are shown in table 1.

TABLE 1 monitoring measurement items

Note: h₀Tunnel burial depth

The construction process flow is shown in figure 1.

Monitoring measurement method, measuring point arrangement and embedding

1. Observation in the hole

The observation in the hole is divided into two parts of digging surface observation and operated section observation.

1) Observing the excavated surface; the observation of the excavation face occurs after each excavation before the initial concrete injection. The engineering geology and hydrogeology conditions are recorded well, the geological sketch work is well done, and the geological sketch work is recorded in a work record table in detail. For the sections with complicated geological conditions, more image data are needed to be made, so as to be used as the basis for geological changes. When the engineering geological condition with mutation is found in observation, a coping method is rapidly used for processing. 2) Observing the operated area; look over primary support and secondary lining district once every day, the deformation conditions of positions such as shotcrete, stock, steelframe and secondary lining are looked over to the key, judge the stability of primary support, secondary lining and the steadiness of country rock.

2. Hole appearance inspection

The key points of the observation outside the tunnel are the ground surface cracking and sinking of the opening section, the shallow buried section of the opening body, the depression between mountains, the rock mass, the broken zone, the loess cave-forming area and the bias opening, the stable state of the tunnel opening side and the upward slope, the ground surface seepage, the running water and the like. And simultaneously, the ground buildings can be observed.

3. Surface subsidence measurement

The amount of settlement of the earth's surface is measured before the tunnel is excavated. And measuring the surface subsidence of the shallow-buried section, the clearance change in the hole and the vault subsidence in the same transverse section.

Surface subsidence measurements are performed prior to excavation. The horizontal interval of the ground surface settlement observation points is 2-5m, the measurement points around the center line of the tunnel are properly encrypted, the distance from the center line of the tunnel to the farthest ground surface settlement observation point is greater than or equal to the sum of the tunnel burial depth and the tunnel excavation width, namely the measurement range of two sides of the center line of the tunnel is not less than H + B; and not less than 7 points/section. The measurement cross section is located at the same cross section as the measurement in the tunnel.

And (3) arranging measuring points, burying the measuring points in the ground surface by using 30cm phi 20 steel bars, filling the peripheries of the measuring points with concrete, wherein the depth of the concrete is not more than 30cm, and carving a cross on the heads of the steel bars. The ground surface settlement measuring base points are buried in the areas (3-5 times of the diameter of the hole) outside the longitudinal and transverse directions of the tunnel excavation and within the range influenced by the ground surface settlement. At least two base points are buried, so that the correction is more convenient, all the base points and the surrounding water level points are measured together to obtain approximate elevations, and when a controlled building is built in the earth surface, the measurement range is properly enlarged.

The monitoring and measuring time is continued until the secondary lining structure of the tunnel is closed after the ground subsidence is stable, and the burying sections and the number of points are shown in tables 2 and 3. In table 2, H is the tunnel buried depth, and B is the tunnel excavation width.

TABLE 2 vertical spacing of surface subsidence test points

Tunnel buried depth and excavation width	Longitudinal measuring point spacing (m)
		2B<Ho<2.5B	20 to 50
B<Ho≤2B	10 to 20
		Ho≤B	5

TABLE 3 Earth surface subsidence burying position

The frequency of the surface subsidence measurement should be the same as the frequency of the vault subsidence and clearance change measurement. The arrangement of the ground subsidence observation points is shown in figure 2.

4. Building settlement measurement

As shown in fig. 3, in order to ensure that the building cavity is not damaged, non-contact observation point arrangement is adopted, and reflector plate point arrangement observation is arranged on the surface of the building for observation. The buried cross section and the number of dots are shown in Table 4.

Table 4 building settlement burying position

5. Vault subsidence measurement and horizontal clearance change measurement

1) Cross-sectional arrangement

The required spacing between measurement sections for monitoring the necessary measurement items such as clearance change, vault sag, etc. is shown in table 5.

Table 5 project monitoring measuring section spacing table

Grade of surrounding rock	Section spacing (m)
		V	≤5
Ⅳ	≤10
		Ⅲ	≤30
II	Determining the spacing as the case may be (80)

Note: and determining the spacing of the II-grade surrounding rock according to specific conditions.

2) Arrangement of clearance change measuring line and vault sinking measuring point

The point distribution method is characterized in that point distribution positions according to a tunnel excavation method are shown in fig. 4, the distribution height is 1.5m higher than each step for facilitating observation of measuring points, the distribution position and the distribution height of the measuring points can be properly adjusted due to the influence of wind belts and water pipes, reflecting sheets of the measuring points are aligned to the direction of a hole opening, and the length of an exposed primary support surface of the measuring points is not more than 5 cm.

3) Embedding and manufacturing of observation points

Firstly, after the excavation is finished, a phi 8 steel bar is used for 50cm in length, the steel bar is driven into a rock stratum to be not less than 15cm, the steel bar is exposed out of a primary support concrete surface to be not more than 5cm, a hook with an outer leakage end bent by 5cm is used, an iron sheet with the length of 5cm multiplied by 5cm is used for welding the hook, and a reflector sheet is attached to the iron sheet, as shown in figure 5.

Secondly, the section spacing can be set according to the actual geological conditions, and the longitudinal section mileage is buried according to multiples of 5, such as (D6K572+900, D6K572+ 905). The class III surrounding rock is not more than 30m, the class IV surrounding rock is not more than 10m, the class V surrounding rock is not more than 5m, and the dangerous area is properly encrypted;

and thirdly, the observation point is arranged on the stable bedrock, and a vertical hole is drilled on the surface of the bedrock by using an air gun. When an arch is supported in the initial stage, the arch can not be welded by the observation mark; the measuring points are to be observed in an early stage after each excavation, initial values are read within 12h after the excavation, the latest initial values are not more than 24h, and initial deformation values are read before the next excavation is carried out.

And fourthly, anchoring the machined phi 8 steel bar observation mark by using an anchoring agent or mortar, wherein the exposed steel bar head (after concrete spraying is finished) is not more than 5cm, and the surface of the reflector plate faces to the direction of the hole.

When the concrete is sprayed, the part of the observation mark exposed in the air cannot be sprayed, so that the observation surface reflecting sheet is extremely easy to pollute and damage;

sixthly, the observation points need to be marked obviously, and the red paint is coated on the periphery so as to facilitate timely and accurate measurement. If the measuring point is damaged, the measuring point is timely repaired within 4 hours.

Second, the measurement request and the measurement data are sorted and analyzed

1. Measuring frequency

The different measurement items are implemented according to the displacement speed and the distance between the measurement section and the excavation surface according to the following standard, see table 6. Different measurement operations are performed until the deformation is basically unchanged and then the measurement is finished 2-3 weeks later, or the measurement is finished when the two liners are difficult to observe immediately. For shallow-buried section, expansive and compressive surrounding rock, when the displacement is not slowed down for a long time, the measurement duration is increased properly after being researched by different parties, and the measurement frequency is shown in table 7.

TABLE 6 monitoring and measuring frequency determined by distance from excavation face

Measuring the distance (m) between the section and the excavation working face	Measuring frequency
		(0～1)B	2 times/d
(1～2)B	1 times/d
		(2～5)B	1/2-3 d
>5B	1 time/7 d

TABLE 7 measurement of frequency (in terms of displacement speed)

Speed of displacement (mm/d)	Measuring frequency
		≥5	2 times/d
1～5	1 times/d
		0.5～1	1/2-3 d
0.2～0.5	1 time/3 d
		＜0.2	1 time/7 d

2. Raw data acquisition

1) And collecting data of surrounding rock convergence and vault settlement by using a total station instrument to measure three-dimensional coordinates without a prism.

2) The foundation points and the measuring points are buried according to the relevant standards, so that the stability of monitoring and measuring data is ensured. And obtaining an initial monitoring value quickly after the measuring point is buried.

3) The initial time period after tunnel excavation has rapid deformation and stress change, and the monitoring measurement data in the time period is very critical to the estimation of the final displacement and stress in the later period, so the initial value is required to be read out quickly so as to grasp the initial dynamics of surrounding rocks and structures more quickly. When the field situation is not consistent with the design, the monitoring measurement items and contents need to be adjusted quickly.

4) After the tunnel face is excavated, monitoring measuring points are set quickly, initial values of vault crown settlement and convergence measurement are completed within 12 hours after excavation, other measurements are started within 24 hours after each excavation and are completed before the next cycle of excavation.

5) During measurement, the sight line is not blocked, and data acquisition is carried out when no large-scale mechanical equipment works around the measuring instrument, so that the accuracy and reliability of the acquired data are ensured.

6) The monitoring measurement data must be checked and rechecked on site, and retest is carried out in time when abnormality is found.

7) The original data record adopts an observation system with automatic record and automatic analysis.

8) Special personnel are required to arrange and maintain data, and repeated checking and examination are required in the process of inputting and processing data, so that errors are prevented.

9) To ensure the true reliability and connectivity of metrology data collection, the following approach is used: the measuring instrument is kept by a special person, and can be put into use after different devices such as measuring equipment, a sensor and the like are corrected to reach the standard. In the monitoring process, the implementation rule is strictly followed, and the storage and calculation management of the measurement data is performed by using a computer system.

10) The situation of measuring point damage often occurs in the field operation process, which causes the discontinuity of monitoring and measuring data and restricts the accurate analysis of the monitoring and measuring result. If the measuring point is damaged, the measuring point is buried around the damaged measuring point. If the measuring point is loosened, the rapid consolidation is needed, the measurement data in the current day is useless, and the initial value is read again after the measuring point is not moved.

3. Data arrangement and analysis

1) And after data are collected each time, the data are quickly sorted, the electronic data are integrally transmitted and uploaded to an engineering network platform through a network, and software is adopted for data sorting and formation of a temporal curve graph.

2) The computer client platform obtains the initial time curve to develop regression analysis, and predicts the highest value and change rate which are possible to generate.

3) When the data is not synchronized, corresponding measures are made according to detailed conditions by organization design, supervision and construction unit research of a field command department.

4. Stability determination and management level

The preliminary bracing deformation management grade of the double-line tunnel is shown in the table 8.

Table 8 management grade table for preliminary bracing deformation of double-track tunnel

The tunnel stability needs to combine on-site observation and displacement change rules, and the observation result and the displacement speed are judged by integrating the tunnel excavation working face condition and the supporting condition.

The bracing is reinforced or the lining is quickly implemented when the following instability conditions occur:

1) partial stones collapse or slide in a laminar mode, and a plurality of cracks and steel frame bending occur in a sprayed and mixed mud layer;

2) the change rate of the horizontal clearance of the tunnel and the vertical movement rate of the vault or the bottom plate are obviously reduced;

3) the accumulated displacement relative value of the tunnel reaches 2/3 of the limit displacement, and the trend that the displacement speed is remarkably slowed down is still not found;

4) the primary support is nearly immersed in the size of the secondary lining structure.

5. Data rechecking and examining system

The review and examination of data is a relatively important task. After the data are uploaded to the computer client, the data are analyzed in time, and some information reflected by data change is predicted. The data is examined as early as possible. And implementing the principles of 'quick uploading of observation data, monitoring and timely pre-analyzing, quick finding out reasons for abnormal data and repeatedly monitoring abnormal monitoring points'. The abnormal data is repeatedly measured by analyzing and checking the abnormal data.

If the retest data is matched, the reason is analyzed, the number of times of observing abnormal data points is increased, and a treatment method is adopted according to the sedimentation velocity. And (5) finding the potential safety hazard, analyzing the reason and submitting an exception report. The uploaded data is analyzed within 12h, the change rule of the data is summarized, the operation condition is evaluated, and a stage analysis report is submitted to guide the operation in the later stage.

5.3.3 metrology data feedback and processing strategies

And the monitoring measurement information feedback is to evaluate the safety of the project according to the analysis result of the monitoring measurement data and provide corresponding project strategies and suggestions.

1. The smoothness of the monitoring and measuring information transmission channel is ensured, and the feedback is fast and efficient. From data collection to uploading to the server, the time cannot be greater than 1 hour.

2. The measuring tense curve is obtained through the monitoring and measuring information platform, so that the stability of surrounding rocks, the working condition of a supporting structure and the degree of restriction on the surrounding environment are judged, design parameters are verified and improved, and construction is guided.

3. When the data change is abnormal, the monitoring and measuring responsible person needs to quickly inform the working area responsible person and project chief worker. Measures such as thickening a concrete spraying layer, encrypting or lengthening an anchor rod, radially grouting, increasing a steel frame, increasing temporary support, backfilling back pressure and the like are adopted in time according to specific conditions;

4. and data acquisition and uploading on the same day are finished 18 o' clock each day, the monitoring information platform immediately finishes data analysis, a curve graph is generated, and early warning is carried out on overrun data. And carrying out stage analysis according to weeks, summarizing the change rule of the monitoring and measuring data, evaluating the construction condition and guiding subsequent construction.

5. When the displacement rate of the measuring point is more than or equal to 5mm/d, the observation frequency is encrypted, a project department technician and a field responsible person jointly analyze the reason and the processing method on the operation field, and when a special method (changing the design operation mode and increasing the number of projects) is utilized, the scheme is reported to a supervision station and a command department and then is implemented;

6. cause analysis was performed by the department of entry technician and the field leader when the rate was >10mm/d for 2 consecutive days. Reinforcing measures such as primary support or temporary support and the like for the section of surrounding rock, and monitoring and measuring the section and frequency in an encrypted manner;

7. when the displacement rate of the measuring point is more than 15mm/d, construction and personnel evacuation are suspended, and a project owner organizes related personnel immediately to analyze the reason, and simultaneously, an efficient method is used for preventing deformation. And the situation is immediately informed to a design and supervision unit, the design and operation are quickly organized by a chief officer, the supervision unit explores a determined scheme, and the construction unit quickly implements the scheme.

8. The evaluation level of engineering safety and the corresponding coping method are as follows:

the organization and measures for evaluating engineering safety are shown in Table 9.

TABLE 9 engineering safety assessment organization and countermeasure table

The engineering safety evaluation process is shown in FIG. 6

9. Corresponding measures are taken when yellow or red early warning (including false early warning generated by error data) occurs on the surrounding rock monitoring measurement observation value:

1) when yellow early warning appears in monitored measurement data, a technical responsible person and a measurement responsible person in a work area confirm and analyze the reason of the yellow early warning, and report a general worker, an safety quality department and a project department of a project department;

2) when the red early warning appears in the monitoring measurement data, the tunnel site construction operators immediately stop construction and rapidly leave the construction site, the monitoring measurement chief responsible persons and the work area technical responsible persons must find out the reasons within 2 hours, the written condition explanation is provided, the chief persons, the quality safety department and the engineering department of the project department are reported, corresponding engineering countermeasures are taken, meanwhile, the quality safety department of the supervision unit and the meter climbing command department is reported, and the construction cannot be recovered before the red early warning reasons are not found out.

3) Processing of early warning information

Firstly, the construction unit confirms the reason of the early warning, and after the construction unit takes precautionary measures, the construction unit informs the management party of the tunnel monitoring and measuring information system to cancel the early warning signal in time.

Secondly, when the early warning is eliminated, the following should be noted on the client: the specific reasons for early warning, construction mileage of upper guidance and lower guidance of construction, a method for early warning treatment and the like.

5.3.4 monitoring the submission and arrangement of measurement results

The monitoring of the measured data, the analysis and the arrangement meet the following requirements:

1. and after each measurement, the electronic data is transmitted to the online client integrally through the network in time. By using

And (3) carrying out data arrangement and forming of a temporal curve by software of a tunnel and underground engineering construction monitoring information system.

2. The initial time-state curve obtained by the platform needs to be subjected to regression analysis, and the highest value and the change rate which are possibly generated are estimated.

3. When data is abnormal, a corresponding method is researched and established according to the detailed condition.

4. And a strict system for rechecking and examining the monitoring and measuring data is established, so that the accuracy of the monitoring data is ensured.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. A monitoring and measuring method for a tunnel shallow buried underground ground surface building is characterized by comprising the following steps;

in-hole observation and out-of-hole observation;

the observation in the hole comprises digging surface observation and operated section observation; hole appearance inspection includes observation of ground buildings;

measuring the surface settlement and the building settlement;

setting surface settlement observation points at a transverse interval of 2-5m before tunnel excavation, and encrypting measurement points around the center line of the tunnel; the distance from the center line of the tunnel to the farthest ground surface settlement observation point is greater than or equal to the sum of the tunnel burial depth and the tunnel excavation width; the number of observation points per section is more than 7;

vault subsidence measurement and clearance change measurement;

determining the section spacing according to the surrounding rock level; and (4) distributing points according to an excavation method, wherein the height of the points is higher than that of each step, the reflection sheet of the measuring point is aligned to the direction of the hole, and the measuring point exposes the initial supporting surface.

2. The method for monitoring and measuring the ground surface building penetrating through the shallow tunnel buried area according to claim 1, wherein at least two ground surface settlement measuring base points are arranged, and are buried in areas which are 3-5 times of the outer diameter of each of the longitudinal direction and the transverse direction of the tunnel excavation and are within the range influenced by the ground surface settlement.

3. The method as claimed in claim 1, wherein when the ground subsidence observation points are arranged,

when the ground surface settlement observation point is on the ground, the steel bars are buried in the ground surface, the periphery of the ground surface settlement observation point is filled with concrete, and the depth of the concrete is less than or equal to 30 cm; when the reflector is arranged on a building, the reflector is arranged on the surface of the building for observation.

4. The method of claim 1, wherein the interval between fracture surfaces in class III wall rock is less than or equal to 30 m; the interval between the IV-grade surrounding rock sections is less than or equal to 10m, the interval between the V-grade surrounding rock sections is less than or equal to 5m, and the dangerous sections are properly encrypted.

5. The method for monitoring and measuring the tunnel shallow buried underground ground surface building according to claim 1, wherein the measuring point in the tunnel is driven into the rock stratum by using a steel bar after the excavation is finished, the driving distance is more than 15cm, the concrete surface of the steel bar exposed out of the primary support is less than or equal to 5cm, the outer leakage end is provided with a hook, an iron sheet is welded on the hook, and finally the reflector sheet is attached to the iron sheet and faces to the opening of the tunnel.

6. The method of claim 1, wherein the surface subsidence measurement, the vault subsidence measurement and the clearance variation measurement are performed on the same cross section.

7. The method of claim 1, wherein the surface subsidence measurement, the vault subsidence measurement and the clearance change measurement are measured by a total station.

8. The method of claim 1, wherein the measurement frequency of the surface subsidence measurement, the vault subsidence measurement and the clearance variation measurement is the same according to the monitoring measurement frequency determined by the distance from the excavation face.

9. The method of claim 1, wherein the time for monitoring and measuring the surface subsidence measurement, the vault subsidence measurement and the clearance variation measurement is continued until the surface subsidence is stabilized until the secondary lining structure of the tunnel is closed.

10. The method according to claim 1, wherein after the raw data is collected, the data is sorted and a temporal curve is formed; and (5) performing regression analysis according to the temporal curve to predict the highest value and the change rate of the settlement.

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