A shield settlement control method and its system

Abstract

A shield settlement control method, its model and application system of the present invention belong to the technical field of shield settlement control. Aiming at the above deficiencies of the current mainstream shield settlement control theory in the industry, the present invention breaks through the traditional shield settlement control theory and adopts a "3+1" model of [slag discharge balance ratio + shield body filling rate + shield tail filling rate + formation loss control coefficient] to characterize formation loss, thereby realizing a method for effectively controlling shield construction settlement, and further expanding the development and application, integrating with the shield construction information platform to develop a shield settlement control automatic warning system. The present invention achieves a revolutionary breakthrough in the shield automatic settlement control technology in the industry.

Description

Technical Field

[0001] The present invention belongs to the technical field of shield settlement control theory and technology, and specifically relates to a shield settlement control method and its application model, as well as an application system (shield settlement automatic warning system) constructed based on its control model. Background Art

[0002] Traditional Shield Settlement Control Theory and Its Limitations

[0003] The mechanism of the influence of shield construction on ground settlement is very complex. Generally, it is considered that the ground loss caused by shield construction and the reconsolidation of the surrounding soil strata caused by shield disturbance are the fundamental reasons for ground settlement; for soft soil strata with a relatively deep burial depth, the ground loss caused by shield construction is the main factor leading to ground settlement. Ground loss is the difference between the volume of the soil excavated by the shield and the volume of the completed tunnel. The volume of the completed tunnel includes the volume of filling materials such as synchronous grouting wrapped around the tunnel periphery. The ground loss rate is the percentage of the ground loss to the theoretical soil discharge volume of the shield.

[0004] In the current mainstream shield settlement control theory in the industry, Peck theory believes that under the assumption of ideal conditions, the volume of surface settlement caused by shield construction should be equal to the volume of ground loss, and it is assumed that the ground loss is evenly distributed along the tunnel length, and the lateral distribution of the ground settlement trough presents the form of a normal distribution curve. Then the ground loss rate is:

[0005]

[0006] In this empirical formula, R is the ground loss rate, i is the width of the surface settlement trough, S max is the maximum surface settlement value, and V is the cross-sectional area of the shield.

[0007] Peck theory based on the concept of this ground loss rate has three major limitations in the actual application process:

[0008] 1) It cannot be directly measured. It can only be measured manually by measuring i and S max to calculate inversely, and it cannot be automatically measured by technical means such as sensors.

[0009] 2) Its calculation cannot be accurate. In actual projects, the surface of the area where the shield passes through is often roads, waterweeds, rivers, mud, buildings, etc., resulting in the inability to accurately identify the surface settlement trough, or even unable to measure it at all.

[0010] 3) Its calculation is seriously lagged. The surface settlement of the shield has hysteresis. Generally, it takes 1 week to 1 month after the shield passes through for the influence of the ground loss to be gradually and completely transmitted to the surface. Calculating the shield ground loss rate through the surface settlement trough at this time has no foresight and has no practical risk control significance for shield construction and passing through.

[0011] Industry Development and Its Safety Requirements

[0012] The Shanghai urban rail transit mainly consists of underground shield tunnel projects, with complex working conditions and high safety requirements. For example, the tunnel-bridge ratio of the Airport Link is 96.6%, and all of the Jia-Min Line is underground shield tunnel project. The shield of the Airport Line passes through up to 137 sensitive structures in the urban center area, and the Jia-Min Line passes through up to 186. Among them, the shield of the Airport Line runs parallel to the Shanghai-Hangzhou High-Speed Railway for up to 5.8 km, with a control accuracy of up to 2 mm, high risk and great difficulty. The feasibility study, preliminary design and construction plan documents all clearly state that the formation loss rate should be strictly controlled during shield construction. For example, the formation loss rate of some shield tunneling is less than 3‰. At present, the formation loss rate is a core theoretical index to measure the level of shield construction and whether it can safely pass through sensitive structures, and it is also a clear control index put forward by the design documents for shield construction. Summary of the Invention

[0013] In view of the above deficiencies of the current mainstream shield settlement control theory in the industry, the present invention discloses a brand-new shield settlement control theory and method, which is characterized in that the present invention breaks through the traditional shield settlement control theory, adopts a "3 + 1" model of

slag discharge balance ratio + shield body filling rate + shield tail filling rate + formation loss control coefficient

[0014] The technical solution to be protected is established as

[0015] Technical Solution 1

[0016] A shield settlement control model, characterized in that:

[0017] In the first part, if the shield machine is a slurry balance shield machine, the model includes

[0018] Wherein, i0 is the formation loss control coefficient, ρ1 is the density of the incoming slurry, ρ2 is the density of the discharged slurry, ρ is the formation density, Q1 is the incoming slurry flow rate, Q2 is the discharged slurry flow rate, S0 is the over-excavation area, S1 is the excavation area, S2 is the axial projection area of the shield body gap, S3 is the axial projection area of the shield tail gap, and v is the shield propulsion speed;

[0019] i1 is the slag discharge balance ratio, wherein, ρ1 is the density of the incoming slurry, ρ2 is the density of the discharged slurry, Q1 is the incoming slurry flow rate, Q2 is the discharged slurry flow rate, S0 is the over-excavation area, S1 is the excavation area, v is the shield propulsion speed, and ρ is the formation density;

[0020] i2 is the shield filling rate, where is the injection flow rate of a single hole (the i-th hole) in the shield injection, S2 is the axial projection area of the shield void, and v is the shield propulsion speed;

[0021] i3 is the tail shield filling rate, where is the injection flow rate of a single synchronous grouting hole (the i-th synchronous grouting hole); S3 is the axial projection area of the tail shield void; v is the shield propulsion speed;

[0022] Second part, if the shield machine is an earth pressure balance shield machine, the model includes

[0023] where, i0 is the formation loss control coefficient, ω is the screw conveyor rotation speed, m is the mass discharged per single rotation of the screw conveyor, ρ is the formation density, S0 is the overexcavation area, S1 is the excavation area, v is the shield propulsion speed, S0 is the overexcavation area, S1 is the excavation area, S2 is the axial projection area of the shield void, and S3 is the axial projection area of the tail shield void;

[0024] i1 is the slag discharge balance ratio, where ω is the screw conveyor rotation speed, m is the mass discharged per single rotation of the screw conveyor, S0 is the overexcavation area, S1 is the excavation area, v is the shield propulsion speed, and ρ is the formation density;

[0025] i2 and i3 are the same as those of the slurry shield;

[0026] The above i0 / i1 / i2 / i3 algorithm formulas constitute the "3 + 1" algorithm model of the present invention [slag discharge balance ratio + shield filling rate + tail shield filling rate + formation loss control coefficient], which is used to characterize the formation loss generated by shield (slurry shield and earth pressure balance shield) construction, so as to control the influence of shield construction on soil layer settlement, and is the first in the field.

[0027] Technical solution two

[0028] A shield settlement automatic warning method, characterized in that: based on the algorithm models i0 / i1 / i2 / i3 and its safety index database [a i , b i described in Technical solution one, embed it into the shield construction information system to form a shield settlement automatic warning system, calculate the current i1 / i2 / i3 / i0 values in real time, and compare them with the indicators in its safe interval in real time. Once it exceeds the warning interval then the shield information system automatically sends a warning message to relevant personnel for shield construction intervention and disposal. The on-site professional personnel check the relevant shield construction parameters in the model and adjust them step by step until i1 / i2 / i3 / i0 returns to the safe interval [ai , b i , when i1 / i2 / i3 / i0 ∈ [a i , b i , the shield safety warning disposal is completed, thereby realizing the safety control of the shield construction and crossing on the settlement of the ground and surrounding structures.

[0029] Ideally, the index of i1 / i2 / i3 / i0 should be equal to 1. However, geological conditions, shield burial depth, shield filling materials and their ratios also have a certain impact on the above indicators. According to different geological conditions, the safety control index ranges of different geological conditions and working conditions are summarized as i1 / i2 / i3 / i0 = i i ∈ [a i , b i , a i , b i are respectively the lower limit value and the upper limit value of the safety interval of i i , and a safety index database for different geological conditions and different burial depths of soft soil can be established through data accumulation of multiple projects [a i , b i . Generally, based on preliminary construction experience and economic considerations, i i can be initially valued as i1 ∈ [0.9, 1.1], i2 ∈ [0, 1.1], i3 ∈ [1.1, 1.3], i0 ∈ [1, 1.2]. With the accumulation of relevant data in the shield construction of the present invention, the safety index database can be further corrected and enriched to more accurately guide the shield construction and risk control under different geological conditions and working conditions.

[0030] Technical solution three

[0031] A shield settlement automatic warning system, characterized in that a configuration file is set at the same time, and both the warning system and the configuration file run and are stored in an information platform; the shield settlement automatic warning system includes a calculation system, a safety index database, and a risk determination and warning system; the calculation system includes an algorithm model.

[0032] An implementation plan of a shield settlement automatic warning system, the implementation plan involves a shield information platform serving project management, and a PLC control system and a data acquisition system are provided in the shield machine control room on site. Various sensors are provided for monitoring the operating states of the propulsion system, the mud circulation system, the Claysol injection system, and the synchronous grouting system, as well as actuators corresponding to regulating the operating states of each system;

[0033] The implementation involves the innovative part: the shield settlement automatic warning system and the configuration file, which run and are stored on the information platform; the shield settlement automatic warning system includes a calculation system, a safety index database, and a risk determination and warning system; the calculation system includes an algorithm model.

[0034] The current working conditions and equipment operation data obtained in real time by various sensors on the shield machine are stored in the data acquisition system and synchronously uploaded to the shield settlement automatic warning system via the data acquisition system.

[0035] The implementation also involves an operation client.

[0036] Among them:

[0037] The staff consult the engineering geological exploration data and write the formation density ρ into the configuration file through the usage page of the shield information platform; the configuration file also pre-defines parameter information such as the front shield diameter d1, the tail shield diameter d2, the overexcavation angle θ, the cutter head excavation diameter r, and the overexcavation cutter extension amount l.

[0038] The current working conditions and equipment operation data uploaded by the data acquisition system include the shield propulsion speed v, the inlet mud density ρ1, the outlet mud density ρ2, the inlet mud flow rate Q1, the outlet mud flow rate Q2, and the single-hole injection flow rate of the shield body injection The single-hole injection flow rate of synchronous grouting The calculation system retrieves the configuration file information, calculates the overexcavation area S0, the excavation area S1, the axial projection area S2 of the shield body gap, and the axial projection area S3 of the tail shield gap; the calculation system inputs the calculated overexcavation area S0, excavation area S1, axial projection area S2 of the shield body gap, axial projection area S3 of the tail shield gap, and the current working conditions and equipment operation data uploaded by the data acquisition system into the algorithm model, and after running, obtains the current i1 / i2 / i3 / i0 values.

[0039] The usage page of the shield information platform can display the current i1 / i2 / i3 / i0 values.

[0040] The operation client can receive, consult, and display the current i1 / i2 / i3 / i0 values.

[0041] The risk determination and warning system uses the output current i1 / i2 / i3 / i0 values to compare with the index thresholds [a i , b i in the safety index database, and after comparison, judges the construction operation status of the current on-site shield machine:

[0042] When i i exceeds the warning range An early warning prompt and operation prompts for relevant shield construction parameters in the model are sent through the shield informatization platform to guide relevant personnel to carry out shield construction intervention and disposal. The on-site professionals holding the operation client check the relevant shield construction parameters in the model and gradually adjust them. In the control room, the corresponding actuators are adjusted through the PLC control system;

[0043] Cyclic closed-loop feedback;

[0044] Until the current working conditions and equipment operation data obtained by various sensors in real time are provided to the shield informatization platform system, and the current i1 / i2 / i3 / i0 returns to the safe range [a i ,b i , that is, when i i ∈[a i ,b i , the shield settlement automatic early warning system completes the shield safety early warning and disposal;

[0045] Thus, the above technical solutions can achieve the safety control of shield construction and tunneling on the ground and surrounding structures. Description of the Drawings

[0046] Figure 1 It is a schematic diagram of the three regions of the cutter head area, shield body area and shield tail area of the shield equipment

[0047] Figure 2 It is the implementation plan of the shield settlement automatic early warning system (system composition and application implementation principle of Embodiment 1) Detailed Implementation Modes

[0048] The technical solutions of the present invention are further introduced below in conjunction with the drawings, general knowledge of shield machines and implementation application examples.

[0049] Introduction to the working principle and construction of the industry's shield machines:

[0050] Shield machines usually have two basic types: slurry shield machines and earth pressure balance shield machines. The main components include a cutter head system, a shield body system (front shield, middle shield and tail shield), a segment erection system, a propulsion system, a muck discharging system, a synchronous grouting system, a Clayshield injection system, a control system, a data acquisition system, a guidance system, etc. Among them, the muck discharging system of the slurry shield machine consists of a mud circulation system and a mud separation station, and the muck discharging system of the earth pressure shield machine consists of a screw conveyor and a belt conveyor system. Communication systems, PLC control systems, data acquisition systems and human-machine operation interfaces are configured on the shield machine to centralize various data and instructions of the instruments, sensors and actuators on the shield machine in the driver's operation cab. Various actuators can generally be operated through the local machine control panel or the operation cab control panel.

[0051] The cutter head system rotates to excavate and cut the soil mass, the shield system protects the space inside the shield machine and supports the equipment and instruments inside the shield machine, the segment erection system is used to install tunnel segments to form an underground tunnel, the propulsion system mainly consists of propulsion cylinders to push the shield machine forward, the muck removal system transfers the soil mass cut by the cutter head to the outside of the shield machine. For a slurry shield machine, the slurry circulation system is used to carry the muck in the form of slurry through the slurry pipeline to the surface slurry separation station and then carry out external transportation and treatment. For an earth pressure balance shield machine, the screw conveyor is used to transport the muck in the cutter head area to the belt conveyor transportation system and then transported out of the tunnel by a transport trolley for treatment.

[0052] With the development of the industry, for example, in the Shanghai urban rail transit project, the excavation diameter of the cutter head of the super-large diameter shield machine is 50 - 60 mm larger than the shield diameter, which is beneficial to reducing the friction during the forward movement of the shield. As a result, a construction gap is formed in the shield area. In this sensitive area, this gap needs to be filled in time to reduce soil and ground settlement. Generally, the Clayshield system injects fillers from the shield outward. The Clayshield system consists of instruments such as a power motor, a Clayshield injection pump, a mixing tank, a flow meter, a pressure gauge, and a control panel. Another example is that the tail diameter of the shield machine on the airport line connection line is 370 - 410 mm larger than the outer diameter of the segment. As a result, a construction gap is formed in the tail area of the shield. This gap must be filled in real time to control soil and ground settlement. This gap is filled with mortar injected in real time by the synchronous grouting system. The synchronous grouting system consists of a hydraulic power unit, a synchronous grouting pump, a counting sensor, a pressure sensor, a control panel, etc.

[0053] The theoretical basis and application direction of the algorithm model of the present invention:

[0054] During the normal construction of the shield machine, controlling ground loss essentially means controlling in real time the construction gaps formed during shield construction. According to the characteristics of the shield machine, the gaps formed during shield construction can be divided into three areas: the cutter head area, the shield area, and the tail area, as Figure 1 . In the cutter head area, there should be a matching between the shield slurry circulation (or screw conveyor soil discharge for an earth pressure balance shield machine) and the shield propulsion speed to ensure that the amount of soil at the cutting face in the cutter head area is equal to the muck discharge amount of the slurry circulation system, so as to ensure that the gap excavated by the cutter head is filled in time by the forward movement of the machine head. In the shield area, there should be a matching between the injection amount of shield fillers such as Clayshield and the shield propulsion speed (taking Clayshield as an example) to ensure that the formed shield gap is filled in time. In the tail area, there should be a matching between the synchronous grouting filling injection and the shield propulsion speed to ensure that the formed tail gap is filled in time. The present invention controls the gaps in the above three areas to be filled in real time and timely by directly associating with shield construction parameters, realizing the real-time control of ground loss during shield construction, and thus essentially controlling the soil or ground settlement during shield construction in real time.

[0055] The shield settlement control model first disclosed by the present invention:

[0056] Slurry balance shield machine, model:

[0057]

[0058] Earth pressure balance shield machine, model:

[0059]

[0060] The specific descriptions and acquisition channels of the parameters involved in the formulas in the above models are as follows (Table 1):

[0061]

[0062]

[0063] Note: 1, r is the excavation diameter of the cutter head, l is the extension of the overexcavation cutter, and θ is the overexcavation angle;

[0064] 2, S1 = π×r 2 , S2 = S1 - π×d1 2 , S3 = S1 - π×d2 2 , where r is the excavation radius of the cutter head, d1 is the diameter of the shield body, and d2 is the outer diameter of the segment;

[0065] 3, β is the inclination coefficient, is the muck filling coefficient, ρ is the geological density, D is the effective radius of the screw conveyor blade, and H is the pitch of the screw conveyor

[0066] Derivation process of the algorithm model of the present invention (i.e., theoretical verification):

[0067] (Taking the grams of mud effect as an example)

[0068] Step 1 In the cutter head area, the amount of cut muck on the working face is equal to the amount of slag discharged by the slurry circulation system. For the slurry balance shield, it is determined by Formula 1, and for the earth pressure balance shield, it is determined by Formula 2:

[0069] Formula 1: (S0×v + S1×v)×ρ = ρ2×Q2 - ρ1×Q1

[0070] Formula 2: (S0×v + S1×v)×ρ = ω×m

[0071] Step 2 In the shield body area, there should be a matching between the grams of mud effect and other shield body filling injection amounts and the shield propulsion speed, which is determined by Formula 3:

[0072] Formula 3:

[0073] Step 3 In the shield tail area, there should be a matching between the synchronous grouting filling injection and the shield propulsion speed, which is determined by Formula 4:

[0074] Formula 4:

[0075] In Step 4, based on the overall accumulation in the three zones and the above formula, Formula 5 and Formula 6 are obtained respectively:

[0076] Formula 5: —— Slurry balance shield

[0077] Formula 6: —— Earth pressure balance shield

[0078] In Step 5, Formula 1, Formula 2, Formula 3, Formula 4, Formula 5 and Formula 6 are transformed as follows:

[0079] Formula 7: i1 is the slag discharge balance ratio, applicable to slurry balance shield

[0080] Formula 8: i1 is the slag discharge balance ratio, applicable to earth pressure balance shield

[0081] Formula 9: i2 is the shield filling rate

[0082] Formula 10: i3 is the tail shield filling rate

[0083] Formula 11: i0 is the formation loss control coefficient, applicable to slurry balance shield

[0084] Formula 12: i0 is the formation loss control coefficient, applicable to earth pressure balance shield

[0085] In Step 6, the "3 + 1" model of

slag discharge balance ratio + shield filling rate + tail shield filling rate + formation loss control coefficient

[0086] Based on the algorithm model of the present invention and implanting it into the shield information management platform ( See details in: Example 1 ) or even embedding it into the shield machine PLC system or implanting it into the hardware and then interacting with the shield machine control system, through real-time collection of relevant parameters, the information platform or the shield machine can calculate the i1 / i2 / i3 / i0 values in real time.

[0087] Step 7 Ideally, the indices of i1 / i2 / i3 / i0 should be equal to 1. However, geological conditions, shield burial depth, shield filling materials and their ratios also have a certain impact on the above indices. According to different geological conditions, the safety control index ranges for different geological conditions and working conditions are summarized as i1 / i2 / i3 / i0 = i i ∈[a i ,b i , where a i ,b i are respectively the lower limit value and the upper limit value of the safety interval of i i . And a safety index database for different geological conditions and different burial depths of soft soil can be established through data accumulation of multiple projects [a i ,b i . Generally, based on preliminary construction experience and economic considerations, i i can be initially taken as i1 ∈ [0.9, 1.1], i2 ∈ [0, 1.1], i3 ∈ [1.1, 1.3], i0 ∈ [1, 1.2]. As more relevant data in the present invention accumulates during shield construction, the safety index database can be further corrected and enriched, which can more accurately guide shield construction and risk control under different geological conditions and working conditions.

[0088] Application Example Example 1

[0089] The technical solution of this Example 1 system includes the prior art part: a shield informatization platform serving project management, and a PLC control system and a data acquisition system are provided in the shield machine control room on site. Various sensors are provided for monitoring the operating states of the propulsion system, the mud circulation system, the Claysol injection system, and the synchronous grouting system, as well as actuators corresponding to regulating the operating states of each system;

[0090] The technical solution of Example 1 includes the innovative part: a shield settlement automatic warning system and a configuration file; the shield settlement automatic warning system includes a calculation system, a safety index database, and a risk determination and warning system; the calculation system includes an algorithm model;

[0091] The current working conditions and equipment operation data obtained in real time by various sensors on the shield machine are stored in the data acquisition system, and are synchronously uploaded to the shield settlement automatic warning system via the data acquisition system;

[0092] As an example, the technical solution of this application may further include an operation client; by way of example and not limitation, it may be a mobile client such as a mobile phone or a PAD, or it may be a PC terminal;

[0093] Among them:

[0094] The staff consult the engineering geological exploration data and write the formation density ρ into the configuration file through the usage page of the shield informatization platform; the configuration file also pre-sets parameter information such as the front shield diameter d1, the tail shield diameter d2, the over-excavation angle θ, the cutter head excavation diameter r, and the over-excavation cutter extension amount l;

[0095] The current working conditions and equipment operation data uploaded by the data acquisition system include the shield propulsion speed v, the inlet mud density ρ1, the outlet mud density ρ2, the inlet mud flow rate Q1, the outlet mud flow rate Q2, and the single-hole injection flow rate of the shield body injection The single-hole injection flow rate of synchronous grouting The calculation system retrieves the information in the configuration file and calculates the over-excavation area S0, the excavation area S1, the axial projection area S2 of the shield body gap, and the axial projection area S3 of the tail shield gap; the calculation system inputs the calculated over-excavation area S0, excavation area S1, axial projection area S2 of the shield body gap, axial projection area S3 of the tail shield gap, and the current working conditions and equipment operation data uploaded by the data acquisition system into the algorithm model, and after running, obtains the current i1 / i2 / i3 / i0 values;

[0096] The usage page of the shield informatization platform can display the current i1 / i2 / i3 / i0 values;

[0097] The operation client can receive, consult, and display the current i1 / i2 / i3 / i0 values;

[0098] The risk judgment and early warning system uses the output current i1 / i2 / i3 / i0 values to compare with the index thresholds [a i ,b i in the safety index database, and after comparison, judges the construction operation status of the current on-site shield machine:

[0099] When i i exceeds the warning range Then, an early warning prompt and operation prompts for relevant shield construction parameters in the model are sent out through the shield informatization platform to guide relevant personnel to carry out shield construction intervention and disposal. The on-site professional personnel holding the operation client check the relevant shield construction parameters in the model and gradually adjust them, and adjust the corresponding actuators through the PLC control system in the control room;

[0100] Circular closed-loop feedback;

[0101] Until the current working conditions and equipment operation data obtained in real time by various sensors are provided to the shield informatization platform system, and the current i1 / i2 / i3 / i0 returns to the safe range [a i ,b i , that is, when i i ∈[a i ,b i], the shield settlement automatic warning system will complete the shield safety warning disposal;

[0102] Therefore, the above technical solution can realize the safe control of shield construction and crossing of the ground and surrounding structures.

[0103] Innovation of this invention

[0104] The core originality lies in that the present invention proposes an algorithm model.

[0105] The core original algorithm of this invention constitutes the "3+1" shield settlement control model of [slag balance ratio + shield body filling rate + shield tail filling rate + formation loss control coefficient]. It is a brand-new shield settlement control model. This model can reflect the formation loss control situation of shield construction in real time, accurately and effectively, and fundamentally solves the limitations of current shield settlement theory. It proposes a key technical path for shield settlement automation control technology. Therefore, it is bound to be novel, creative and advanced, and has important revolutionary scientific guiding significance for the safety risk management of shield projects.

Claims

1. A shield settlement control method, characterized in that, This method is implemented using a shield settlement control model. If the shield machine is a slurry balance shield machine, the shield settlement control model includes —— Mucking balance ratio, —— Shield filling rate, —— Shield tail filling rate; Or If the shield machine is an earth pressure balance shield machine, the shield settlement control model includes —— Mucking balance ratio, —— Shield filling rate, —— Shield tail filling rate; Given that the three parameters i1 / i2 / i3 have different weight ratios for the influence on formation settlement, the three parameters are fused as follows: Applicable to slurry shield tunneling machines; Applicable to earth pressure balance shield machines; Define i0 as the formation loss control coefficient, ρ1 as the mud inlet density, ρ2 as the mud discharge density, ρ as the formation density, Q1 as the mud inlet flow rate, Q2 as the mud discharge flow rate, S0 as the over-excavation area, S1 as the excavation area, S2 as the axial projection area of the shield body gap, S3 as the axial projection area of the tail gap, ω as the screw conveyor rotation speed, m as the mass discharged per single rotation of the screw conveyor, and v as the shield propulsion speed; Inject a single hole into the shield body, the i-th hole, injection flow rate; For the single-hole injection flow rate of the synchronous grouting, the i-th synchronous grouting hole; i2 and i3 are the same as those of the slurry balance shield.

2. The shield settlement control method according to claim 1, wherein, The shield settlement control model substantially controls the formation loss rate during shield construction, and thus essentially controls the ground settlement caused by shield construction.

3. The shield settlement control method according to claim 2, characterized in that Based on the model i0 / i1 / i2 / i3 and its safety index database [a i ,b i , embed it into the shield construction informatization system to form an automatic shield settlement warning system, calculate the current i1 / i2 / i3 / i0 values in real time, and compare them with the indicators in its safety range in real time. Once it exceeds the warning range the shield construction informatization system will automatically send a warning message to relevant personnel for shield construction intervention and disposal. The on-site professionals will check the relevant shield construction parameters in the model and adjust them step by step until i1 / i2 / i3 / i0 returns to the safety range [a i ,b i . When i1 / i2 / i3 / i0 ∈ [a i ,b i , the shield safety warning disposal is completed, thereby realizing the safety control of the ground and surrounding structures during shield construction and tunneling.

4. A shield settlement automatic early warning system implemented by using the shield settlement control method of claim 3, characterized in that, At the same time, a configuration file is set up; Both the warning system and the configuration file operate and are stored in the information platform.

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