Rectangular pipe gallery layered backfill soil monitoring method and monitoring system

Abstract

The application discloses a kind of rectangular pipe gallery layered backfill monitoring method and monitoring system, belong to municipal infrastructure construction monitoring technical field.It includes the following steps: according to pipe gallery structure, delimit the monitoring section of layered backfill;Before each layer backfill, along pipe gallery cross section and longitudinal section, sensor array is arranged according to grid rule;Collect the reference parameter of undisturbed soil and first layer backfill, and carry out accuracy verification;After each layer backfill is completed, the measured parameter of the layer backfill is collected in real time, compared with the reference data collected, after accuracy verification, upload to central processing unit;Based on the reference data uploaded in real time, after pre-processing, input compaction degree evolution model and local settlement prediction model, generate layered quality score and associate grade table output construction suggestion.The application combines the double dynamic analysis of compaction degree evolution model and local settlement prediction model, realizes the real-time monitoring of dry density, settlement and load stress in the process of layered backfill.

Description

Technical Field

[0001] This invention relates to the field of municipal infrastructure construction monitoring technology, and in particular to a method and system for monitoring layered backfill soil in rectangular pipe corridors. Background Technology

[0002] In municipal underground engineering, especially in the construction of urban integrated utility tunnels, rectangular cross-section tunnel structures typically require layered backfilling. The quality of the backfill directly affects the stability of the structure and subsequent settlement control. Currently used methods, such as manual sampling to test compaction and settlement observation point measurement, have drawbacks such as limited monitoring accuracy, slow response, and inability to achieve automation, making it difficult to meet the needs of real-time assessment of the layered compaction process and local settlement trends.

[0003] Therefore, there is an urgent need for an integrated, efficient, and visualized layered backfill monitoring system to achieve dynamic control over the entire backfill soil quality process and provide early warnings and construction optimization suggestions when quality anomalies occur. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for monitoring the layered backfill soil of rectangular utility tunnels, so as to realize dynamic monitoring of backfilling operations during the construction of urban integrated utility tunnels, ensure real-time control of compaction quality and settlement risk, thereby improving structural stability, reducing later maintenance costs, and assisting in intelligent construction and scientific decision-making.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention discloses a method for monitoring layered backfill soil in rectangular utility tunnels, comprising the following steps:

[0007] S1. Monitoring area selection: Delineate the monitoring sections for layered backfilling based on the structure of the utility tunnel;

[0008] S2. Monitoring point layout: Before backfilling each layer, sensor arrays are laid out along the cross-section and longitudinal section of the pipe gallery according to a grid pattern.

[0009] S3. Baseline Data Acquisition: Collect baseline parameters for the undisturbed soil and the first layer of backfill soil, and verify the accuracy.

[0010] S4. Real-time data acquisition and transmission: After each layer of backfill is completed, the measured parameters of the backfill soil in that layer are acquired in real time, compared with the benchmark data acquired in step S3, and after accuracy verification, are uploaded to the central processing unit.

[0011] S5. Data Processing and Dynamic Evaluation: Based on the data uploaded in real time in step S4, after preprocessing, the data is input into the compaction degree evolution model and the local settlement prediction model for calculation, generating a layered quality score and outputting construction suggestions by associating it with the grade table.

[0012] In S5, the formula for the compaction degree evolution model is:

[0013]

[0014] In the formula, t It's time, and the unit is seconds; D i(t) It is the first i Layered backfill soil in time t The compaction degree of the backfill soil at that time; D measured(t) It is the initial density of the undisturbed soil; P j(t) It is the first j External load above the backfill layer, in Pa; H j It is the first j The thickness of the backfill layer, in cm; K j It is the soil consolidation coefficient; α j It is the first j The incremental compaction coefficient of the backfill soil; δP j It is the first j Additional stress in the backfill soil, expressed in Pa; i Indicates the current backfill soil layer. j For the first i All soil layers above the backfill soil;

[0015] in, K j and α j It is pre-calibrated through indoor geotechnical tests and stored in the central processing unit parameter database, automatically matched according to the soil layer type during construction, and supports revision.

[0016] A further option: In S3, the reference parameters include porosity, compressive modulus, additional stress, initial stress, and external load;

[0017] In S4, the measured parameters include: dry density, moisture content, settlement, number of compaction passes, and external load.

[0018] A further option: In S5, the formula for the local settlement prediction model is:

[0019]

[0020] In the formula, t It's time, and the unit is seconds; It is time tThe predicted settlement of backfill soil, in cm; It is the compression coefficient of the i-th layer of backfill soil; It is the first i The thickness of the backfill layer, in cm; It is the first i The initial stress above the backfill layer, in Pa; It is the first i External load above the backfill layer, in Pa; K i It is the soil consolidation coefficient; It is a correction factor for adjusting the influence of external loads; It is the first i Layered backfill soil over time t The varying external load, in Pa;

[0021] K i and It is pre-calibrated through indoor geotechnical tests and stored in the central processing unit parameter database, automatically matched according to the soil layer type during construction, and supports revision.

[0022] A further approach: In S5, the stratified quality score is obtained using the following formula:

[0023]

[0024] In the formula, t It's time, and the unit is seconds; It is a quality score; It is the first i The ratio of the target value to the actual value of the compaction degree of the backfill soil in each layer; It is the first i The ratio of the target value to the actual value of the settlement of the backfill soil layer; Control coefficient The sum is 1.

[0025] in:

[0026] D i * (t) Calculated using the following formula:

[0027]

[0028] In the formula, t It's time, and the unit is seconds; This is the target value for compaction. It is the first i Layered backfill soil in time tThe compaction degree of the backfill soil at that time;

[0029] Calculated using the following formula:

[0030]

[0031] In the formula, t It's time, and the unit is seconds; This is a measured settlement, in cm. It is time t The predicted settlement of backfill soil, in cm; This is the error value.

[0032] Further solutions include step S6:

[0033] The stratified quality scoring results and grading tables are presented as evaluation curves, and the evaluation curves, risk levels, and construction recommendations are visualized and output.

[0034] A further proposed solution is to start the data acquisition process immediately after each backfill layer is completed, and to collect dynamic pressure data every 5-10 minutes during the operation of the compaction machinery.

[0035] Further options: P j(t) Calculated using the following formula:

[0036]

[0037] In the formula, For the first k The wet unit weight of the backfill soil, in kN / m³ 3 ; For the first k The thickness of the backfill layer;

[0038] Calculated using the following formula:

[0039]

[0040] In the formula, Q It is the first i Concentrated load above the backfill layer, in N; R It is the radius of diffusion influence, in cm; η (Z j ) is the attenuation factor.

[0041] Further options: Calculated using the following formula:

[0042]

[0043] In the formula, It is the first j The wet unit weight of the soil layer is expressed in kN / m³. 3 ; It is the first j Soil layer thickness, in cm;

[0044] C i Calculated using the following formula:

[0045]

[0046] In the formula, It is the natural porosity, expressed in % %. It is the compressibility modulus, and its unit is Pa.

[0047] Secondly, this invention discloses a monitoring system used in the above-described method for monitoring layered backfill soil in rectangular pipe corridors, comprising:

[0048] The data acquisition module includes a pore pressure gauge, a dynamic pressure sensor, a sedimentation meter, a laser rangefinder, and a nuclear density meter;

[0049] The data processing and modeling module is used to normalize and filter the data collected by the sensor array, and to build a compaction degree evolution model and a local settlement prediction model.

[0050] The central processing unit receives the processed data and outputs control commands and construction adjustment suggestions.

[0051] The assessment and decision support module is used to output hierarchical quality scores based on the results of the data processing and modeling unit and to output construction recommendations by associating the grade table.

[0052] The user interface and visualization module are used to visualize the results output by the evaluation and decision support unit.

[0053] Compared with the prior art, the beneficial effects of the present invention are:

[0054] By integrating multi-source sensors and wireless transmission technology, and combining dual dynamic analysis with a compaction evolution model and a local settlement prediction model, the system achieves real-time monitoring of dry density, settlement, and load stress throughout the layered backfilling process. Based on a physical quantity-driven scoring mechanism, the system automatically outputs construction optimization suggestions, significantly improving the accuracy of compaction quality assessment and the timeliness of settlement risk early warning, forming a closed-loop control system of "monitoring-assessment-decision-making." This method effectively solves the problems of lag and experience dependence in traditional manual sampling and testing, reduces rework rates, and provides intelligent and visualized scientific construction support for urban integrated utility tunnel projects. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the workflow of the present invention;

[0056] Figure 2 This is a cross-sectional view of the sensor layout in this invention;

[0057] Figure 3 This is a longitudinal section view of the sensor layout in this invention;

[0058] In the figure: 1-pore pressure gauge, 2-dynamic pressure sensor, 3-sedimentation gauge, 4-laser rangefinder, 5-nuclear density meter. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] In the description of this invention, it should be noted that the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0061] In this embodiment, a monitoring system for layered backfill soil in a rectangular utility tunnel includes a data acquisition module, a data processing and modeling unit, a central processing unit, an evaluation and decision support unit, and a user interface and visualization unit, wherein:

[0062] like Figure 2-3As shown, the data acquisition module receives and reads data collected by the sensor array. The acquisition frequency can be set according to the construction process, generally set to collect data immediately after each layer of backfilling is completed. The sensor array is deployed in a "layer control + point control" manner, forming a regular monitoring grid along the cross-section and longitudinal section to ensure complete data coverage of key parts for data acquisition. The sensor array specifically includes a pore pressure gauge 1, a dynamic pressure sensor 2, a settlement gauge 3, a laser rangefinder 4, and a nuclear density meter 5. The pore pressure gauge 1 and the dynamic pressure sensor 2 are used to collect the load borne by the soil. The dynamic pressure sensor 2 is also used to record the number of mechanical compaction cycles and the pressure energy applied per unit area. The nuclear density meter 5 is placed in the uppermost soil layer to determine the dry density and moisture content of the backfill soil. The wet density of the backfill soil is calculated from the dry density and moisture content (wet density = dry density × (1 + moisture content); the units of wet density and dry density are both kN / m³). Pore ​​pressure gauge 1 and dynamic pressure sensor 2 are laid in an array on the i-th soil layer. Settlement gauge 3 is inserted vertically from the i+1-th soil layer, penetrating the i+1-th and i-th soil layers. Laser rangefinder 4 and settlement gauge 3 are used to record local settlement changes during the backfilling process. The position of laser rangefinder 4 needs to be set according to the site conditions.

[0063] The data processing and modeling module normalizes and filters the data collected by the sensor array. The processed data is then input into the modeling module, which includes the compaction degree evolution model and the local settlement prediction model. The compaction degree evolution model is used to derive the compaction degree of the i-th layer of backfill soil at time t. Based on compaction energy, dry density, external load, and soil layer thickness, a time-stress coupling analysis was constructed. A local settlement prediction model was used to derive the settlement evolution curve of the backfill area based on the consolidation coefficient, compression modulus, layer thickness, and external load. ;

[0064] The central processing unit receives the processed data and outputs control commands and construction adjustment suggestions.

[0065] The assessment and decision support module includes an assessment model submodule and a decision support submodule. The assessment model submodule calculates the quality standard value based on the calculation results of the modeling submodule and historical data, and obtains the assessment result by comparing it with the quality level evaluation table set in the system (as shown in Table 1 below). The decision support submodule is used to provide a visual report, presenting the assessment curve, risk level and construction optimization suggestions for on-site management.

[0066] Table 1 Quality Grade Evaluation Table

[0067]

[0068] The user interface and visualization module includes a data display submodule and a report generation submodule; the data display submodule is used to display backfill compaction assessment values ​​through a 3D graphical interface. Compared with the predicted settlement value It also integrates with BIM or GIS platforms; the report generation submodule is used to output construction logs, early warning records and quality assessment reports, and to visualize the results output by the assessment and decision support unit.

[0069] like Figure 1 As shown in this embodiment, a method for monitoring layered backfill soil in a rectangular pipe gallery includes the following steps:

[0070] S1. Monitoring area selection: Delineate the monitoring sections for layered backfilling based on the structure of the utility tunnel;

[0071] S2. Monitoring point layout: Before backfilling each layer, sensor arrays are laid out along the cross-section and longitudinal section of the pipe gallery according to a grid pattern.

[0072] S3. Baseline Data Acquisition: Collect baseline parameters for the undisturbed soil and the first layer of backfill soil, and verify the accuracy.

[0073] S4. Real-time data acquisition and transmission: After each layer of backfill is completed, the measured parameters of the backfill soil in that layer are acquired in real time, compared with the benchmark data acquired in step S3, and after accuracy verification, are uploaded to the central processing unit.

[0074] S5. Data Processing and Dynamic Evaluation: Based on the data uploaded in real time in step S4, after preprocessing, the data is input into the compaction evolution model and the local settlement prediction model for calculation, generating a layered quality score and outputting construction suggestions by associating it with the grade table.

[0075] Furthermore: In S3, the reference parameters include porosity, compressive modulus, additional stress, initial stress, and external load data;

[0076] In S4, the measured parameters include: dry density, moisture content, settlement, number of compaction passes, and external load data.

[0077] Furthermore: In step S5, the formula for the compaction degree evolution model is:

[0078]

[0079] In the formula, t It's time, and the unit is seconds; It is the first i The compaction degree of the backfill soil at time t; It is the initial density of the undisturbed soil; It is the first j External load above the backfill layer, in Pa; It is the first j The thickness of the backfill layer, in cm; K j This is the soil consolidation coefficient, and based on the soil type of silty clay, it is taken as 5 × 10⁻⁶. -8 ; It is the first j The incremental compaction coefficient of the backfill soil, based on the soil type of silty clay, is taken as 3×10. -7 ; It is the first j Additional stress in the backfill soil, expressed in Pa; i This is the soil layer currently being calculated. j It is the upper soil layer that affects the current soil layer. i and j The relationship is:

[0080] j Soil layer range: numbered from the surface downwards ( j= 1 is the top layer), up to the target layer. i The layer directly above (i.e.) j=1 arrive j=i-1 ).

[0081] For example: when calculating the first i= At 3 floors, j It is necessary to traverse the first and second layers above it.

[0082] j right i Impact: Topsoil ( j The load, thickness, and soil parameters of the first soil layer are transferred to the next soil layer through the consolidation effect. i layer).

[0083] in, K j and The parameters are pre-calibrated through indoor geotechnical tests (in this embodiment, the calibration is based on indoor consolidation tests) and stored in the central processing unit parameter database. They are automatically matched according to the soil layer type during construction and revision is also supported.

[0084] It should be noted that, K i The value range is 1×10 -8 ~1×10 -5 ; The value range is 1×10 -8 ~7×10 -7 In other embodiments, for example, if the soil type is medium sand, then K i The value is 1×10 -6 , The value is 5×10 -8 .

[0085] Furthermore: In step S5, the formula for the local settlement prediction model is:

[0086]

[0087] In the formula, t It's time, and the unit is seconds; It is time t The predicted settlement of backfill soil, in cm; This is the compressibility coefficient of the i-th backfill layer, which is taken as 2 × 10⁻⁶ based on the soil type being silty clay. -5 ; It is the first i The thickness of the backfill layer, in cm; It is the first i The initial stress above the backfill layer, in Pa; It is the first i External load above the backfill layer, in Pa; K i This is the soil consolidation coefficient, and based on the soil type of silty clay, it is taken as 5 × 10⁻⁶. -8 ; This is a correction factor for adjusting the influence of external loads, with a value of 1×10. -7 ; It is the first i Layered backfill soil over time t The varying external load, in Pa;

[0088] K i The value range is 1×10 -8 ~1×10 -5 ; The value range is 1×10 -6 ~1×10 -4 ; The value range is 8×10 -9 ~3×10 -7 In other embodiments, the soil type is medium sand, then The value is 5×10 -6 , The value is 1×10 -6 , The value is 3×10 -8 .

[0089] K i and It is pre-calibrated through indoor geotechnical tests and stored in the central processing unit parameter database, automatically matched according to the soil layer type during construction, and supports revision.

[0090] Furthermore: In step S5, the stratified quality score is obtained using the following formula:

[0091]

[0092] In the formula, t It's time, and the unit is seconds; It is a quality score; It is the first i The ratio of the target value to the actual value of the compaction degree of the backfill soil in each layer; It is the first i The ratio of the target value to the actual value of the settlement of the backfill soil layer; Control coefficient The sum is 1.

[0093] in:

[0094] Calculated using the following formula:

[0095]

[0096] In the formula, t It's time, and the unit is seconds; This is the target value for compaction. It is the first i Layered backfill soil in time t The compaction degree of the backfill soil at that time;

[0097] Calculated using the following formula:

[0098]

[0099] In the formula, t It's time, and the unit is seconds; This is a measured settlement, in cm. It is time t The predicted settlement of backfill soil, in cm; It is the error value, this error value The value is 0.8.

[0100] Furthermore, it also includes step S6:

[0101] The stratified quality scoring results and grading tables are presented as evaluation curves, and the evaluation curves, risk levels, and construction recommendations are visualized and output.

[0102] Furthermore: In step S4, the data acquisition frequency is to start immediately after each layer of backfilling is completed, and to collect dynamic pressure data every 5-10 minutes during the operation of the compaction machinery.

[0103] Further: P j(t) Calculated using the following formula:

[0104]

[0105] In the formula, For the first k The wet unit weight of the backfill soil, in kN / m³ 3 ; For the first k The thickness of the backfill layer;

[0106] Calculated using the following formula:

[0107]

[0108] In the formula, Q This is a concentrated load, measured in N. R It is the radius of diffusion influence, in cm; It is the attenuation factor, which is determined by distance: the attenuation factor decreases by 0.2 to 0.3 for every 1 meter of distance; the minimum attenuation factor is 0.1 when the value of the attenuation factor is less than 0.1 (to avoid infinitesimal values).

[0109] Further: Calculated using the following formula:

[0110]

[0111] In the formula, It is the first j The wet unit weight of the soil layer is expressed in kN / m³. 3 ; yes j Layer thickness, in cm;

[0112] Calculated using the following formula:

[0113]

[0114] In the formula, It is the natural porosity, expressed in % %. It is the compressibility modulus, and its unit is Pa.

[0115] The following experiments were conducted according to the monitoring system and method of this invention: The experimental site was a rectangular pipe gallery foundation pit with a cross-section of approximately 3.0 m × 2.5 m. Medium sand and silty clay were used as backfill materials. The first to third layers of backfill soil were medium sand, silty clay, and medium sand, respectively, with the moisture content controlled at 8%–12%. The thickness of each layer was approximately 30 cm, and each layer was compacted 6–8 times. Monitoring points were set at the center of the wheel tracks. The dry density and moisture content were measured using a nuclear density meter, the contact pressure was recorded by a dynamic pressure sensor, the excess pore pressure was monitored by a pore water pressure gauge, and the cumulative settlement was tracked by a settlement meter / laser rangefinder. The number of compaction passes was also simultaneously acquired by the dynamic pressure sensor. All sensors were monitored at 30 s intervals. To automatically collect and upload data at sampling intervals, the system calculates the layered compaction degree (D1, D2, D3), layered settlement (S1, S2, S3), and comprehensive score (the comprehensive score is the average of the layered scores) in real time according to the set formula, thereby realizing the dynamic monitoring and evaluation of the compaction quality of layered backfill. The experimental results are shown in Table 1 and Table 2 below.

[0116] Table 1

[0117]

[0118] Table 2

[0119]

[0120] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0121] Therefore, the above description is only a preferred embodiment of this application and is not intended to limit the scope of this application; that is, all equivalent modifications made in accordance with the scope of the claims of this application shall be within the protection scope of the claims of this application.

Claims

1. A method for monitoring layered backfill soil in rectangular pipe corridors, characterized in that, Includes the following steps: S1. Determine the monitoring sections for layered backfilling based on the structure of the utility tunnel; S2. Before backfilling each layer, sensor arrays are laid out along the cross-section and longitudinal section of the pipe gallery according to a grid pattern. S3. Collect the baseline parameters of the undisturbed soil and the first layer of backfill soil, and verify the accuracy. S4. After each layer of backfill is completed, the measured parameters of the backfill soil in that layer are collected in real time, compared with the benchmark data collected in step S3, and after accuracy verification, are uploaded to the central processing unit. S5. Based on the data uploaded in real time in step S4, after preprocessing, input the compaction degree evolution model and the local settlement prediction model to generate a layered quality score and output construction suggestions by associating it with the grade table. In S5, the formula for the compaction degree evolution model is: In the formula, t It's time, and the unit is seconds; D i(t) It is the first i Layered backfill soil in time t The compaction degree of the backfill soil at that time; D measured(t) It is the initial density of the undisturbed soil; P j(t) It is the first j External load above the backfill layer, in Pa; H j It is the first j The thickness of the backfill layer, in cm; K j It is the soil consolidation coefficient; α j It is the first j The incremental compaction coefficient of the backfill soil; δP j It is the first j Additional stress in the backfill soil, expressed in Pa; i Indicates the current backfill soil layer. j For the first i All soil layers above the backfill soil; in, K j and α j It is pre-calibrated through indoor geotechnical tests and stored in the central processing unit parameter database, automatically matched according to the soil layer type during construction, and supports revision.

2. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 1, characterized in that, In S3, the reference parameters include porosity, compressive modulus, additional stress, initial stress, and external load. In S4, the measured parameters include: dry density, moisture content, settlement, number of compaction passes, and external load.

3. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 1, characterized in that, In S5, the formula for the local settlement prediction model is: In the formula, t It's time, and the unit is seconds; It is time t The predicted settlement of backfill soil, in cm; It is the first i The compression coefficient of the backfill soil; It is the first i The thickness of the backfill layer, in cm; It is the first i The initial stress above the backfill layer, in Pa; It is the first i External load above the backfill layer, in Pa; K i It is the soil consolidation coefficient; It is a correction factor for adjusting the influence of external loads; It is the first i Layered backfill soil over time t The varying external load, in Pa; K i and It is pre-calibrated through indoor geotechnical tests and stored in the central processing unit parameter database, automatically matched according to the soil layer type during construction, and supports revision.

4. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 1, characterized in that, In S5, the stratified quality score is obtained using the following formula: In the formula, t It's time, and the unit is seconds; It is a quality score; It is the first i The ratio of the target value to the actual value of the compaction degree of the backfill soil in each layer; It is the first i The ratio of the target value to the actual value of the settlement of the backfill soil layer; For control coefficients, The sum is 1; in: D i * (t) Calculated using the following formula: In the formula, t It's time, and the unit is seconds; This is the target value for compaction. It is the first i Layered backfill soil in time t The compaction degree of the backfill soil at that time; Calculated using the following formula: In the formula, t It's time, and the unit is seconds; This is a measured settlement, in cm. It is time t The predicted settlement of backfill soil, in cm; This is the error value.

5. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 1, characterized in that, It also includes step S6: The stratified quality scoring results and grading tables are presented as evaluation curves, and the evaluation curves, risk levels, and construction recommendations are visualized and output.

6. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 1, characterized in that, The data acquisition frequency in step S4 is to start immediately after each layer of backfilling is completed, and to collect dynamic pressure data every 5-10 minutes during the operation of the compaction machinery.

7. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 3, characterized in that, P j(t) Calculated using the following formula: In the formula, For the first k The wet unit weight of the backfill soil, in kN / m³ 3 ; For the first k The thickness of the backfill layer, in cm; δP j Calculated using the following formula: In the formula, Q It is the first i Concentrated load above the backfill layer, in N; R It is the radius of diffusion influence, in cm; η(Z j ) is the attenuation factor.

8. The method for monitoring layered backfill soil in rectangular pipe corridors according to claim 4, characterized in that, Calculated using the following formula: In the formula, It is the first j The wet unit weight of the soil layer is expressed in kN / m³. 3 ; It is the first j Soil layer thickness, in cm; C i Calculated using the following formula: In the formula, It is the natural porosity, expressed in % %. It is the compressibility modulus, and its unit is Pa.

9. The monitoring system used in the method for monitoring layered backfill soil of rectangular pipe gallery as described in any one of claims 1-8, characterized in that, include: The data acquisition module includes a pore pressure gauge, a dynamic pressure sensor, a sedimentation meter, a laser rangefinder, and a nuclear density meter; The data processing and modeling module is used to normalize and filter the data collected by the sensor array, and to build a compaction degree evolution model and a local settlement prediction model. The central processing unit receives the processed data and outputs control commands and construction adjustment suggestions. The assessment and decision support module is used to generate hierarchical quality scores based on the results output by the data processing and modeling unit, and to output construction recommendations by associating the grade table with the scores. The user interface and visualization module are used to visualize the results output by the evaluation and decision support unit.

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