Shield tunneling perturbation control method

Abstract

The invention relates to the field of shield tunneling, in particular to a shield tunneling micro-disturbance control method which comprises the following steps: calculating the pressure of a soil bin, which is obtained by the sum of lateral horizontal loosening pressure, underground water pressure and set preparation pressure and can be adjusted according to the amount of cut soil and the amount of discharged soil; calculating shield thrust and cutterhead torque, wherein the shield thrust is obtained by the front soil pressure of the shield equipment and the friction force of the soil borne by the side surface of the shield equipment; the cutterhead torque comprises friction torque between cutterhead soil bodies, formation resistance and torque generated by a cutter; calculating the propelling speed, wherein the propelling speed influence factors comprise the soil output speed of the shield tunneling machine, the grouting speed and the shield tail grease injection speed; and controlling the posture of the shield, wherein the control of the posture of the shield is a dynamic adjustment process. Through calculation of a plurality of tunneling influence factors such as a soil bin pressure tunneling state, micro-disturbance control of tunneling is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of shield tunneling, and in particular to a shield tunneling micro-disturbance control method. Background Art

[0002] The shield method is a fully mechanized construction method in the underground excavation method. With the vigorous development of rail transit construction in major cities, the shield method has been widely used due to its good safety, high efficiency and low noise.

[0003] Compared with strata composed of pure mudstone, shield construction in fractured and rich mudstone strata causes greater settlement and disturbance to the strata. For some buildings that are old, have poor structural stability, and weak ability to resist surface deformation, if settlement is not properly controlled, it will cause excessive settlement of the surface and buildings, causing cracks, tilts, or even collapse of the buildings, resulting in significant economic losses and adverse social impacts. Therefore, how to perform micro-disturbance control and reduce stratum settlement during shield excavation in fractured and rich mudstone strata is a problem that technicians in this field need to consider. Summary of the invention

[0004] The purpose of the present invention is to provide a shield tunneling micro-disturbance control method to solve the problems of large settlement during shield construction in cement-rich rock strata with developed fissures in the prior art.

[0005] The technical solution of the present invention is: a shield tunneling micro-disturbance control method, comprising the following steps:

[0006] S1. Calculate the soil bin pressure, which is obtained by the sum of the lateral horizontal loosening pressure, the groundwater pressure and the set preparation pressure, and can be adjusted according to the amount of soil cut and the amount of soil discharge;

[0007] S2, calculating the shield thrust and cutter head torque, wherein the shield thrust is obtained by the front soil pressure of the shield equipment and the friction of the soil on the side; the cutter head torque includes the friction torque between the cutter head and the soil, the formation resistance and the torque generated by the cutter;

[0008] S3, calculating the advancement speed, wherein the factors affecting the advancement speed include the speed at which the shield machine outputs soil, the grouting speed, and the grease injection speed at the shield tail;

[0009] S4. Control of the shield posture. The control of the shield posture is a dynamic adjustment process, including shield zoning control, serpentine correction and rolling control.

[0010] Preferably, the soil bin pressure is calculated as follows:

[0011] The lateral horizontal loosening pressure P1 is:

[0012]

[0013] Where P0 = 0.45 × 2 6-s γw;

[0014] w=1+i(B-5);

[0015] Therefore, P1 = (0.45 × 2 6-s γ(1+i(B-5)));

[0016] Where, S is the surrounding rock type, which can be obtained by looking up the table in the current "Railway Tunnel Design Code", B is the net width of the tunnel (m), i is the rate of increase or decrease of surrounding rock pressure when B increases or decreases by 1m based on B=5m, when B<5m, i=0.2, B>5m, i=0.1;

[0017] Calculation of groundwater pressure P2:

[0018] P2 = qγh;

[0019] Where: q is an empirical value determined based on the permeability coefficient of the soil; γ is the bulk density of water, γ = 10kN / m3; h is the height of the groundwater level from the top of the cutterhead.

[0020] Based on the above calculations, the set soil bin pressure P is:

[0021] P=P1+P2+P 备 ;

[0022] Where P 备 is the set reserve pressure.

[0023] Preferably, when the shield advances, the shield body gradually sinks into the soil, and its thrust gradually increases. The shield thrust is calculated as follows:

[0024] The positive soil pressure is:

[0025]

[0026] The friction force of the soil on the side of the shield equipment is:

[0027]

[0028] Among them, P e is the pressure on the shield machine, P e =γH+P0;

[0029] P1 is the lateral water and soil pressure at the top of the shield machine, P1 = P e K0;

[0030] P2 is the lateral water and soil pressure at the bottom of the shield machine, P2 = (P1 + γH) K0;

[0031] P 01 is the uniform pressure at the bottom of the shield machine,

[0032] Among them, G is the weight of the shield machine, D is the outer diameter of the shield machine, l is the length of the shield machine, and u is the friction coefficient between the shield and the soil;

[0033] The thrust of the shield machine is: F = F1 + F2 + F3;

[0034] Among them, F3 is the friction resistance of the matching trailer, which is an empirical value.

[0035] Preferably, the friction torque between the cutter head and the soil includes the friction resistance torque T1 between the front of the cutter head and the soil; the friction resistance torque T2 between the back of the cutter head and the soil in the pressure chamber; the torque generated by the formation resistance and the cutter is T3, then the cutter head torque is:

[0036] T = T1 + T2 + T3;

[0037] in,

[0038] T2 = W1μ1r;

[0039]

[0040] Where K0 is the lateral earth pressure coefficient, f is the friction factor between the cutterhead and the soil, γ is the gravity density of the soil, H is the tunnel depth (calculated to the center of the tunnel) (m), η is the cutterhead opening ratio of the shield machine, W1 is the cutterhead mass, μ1 is the cutterhead coefficient, r is the cutterhead radius, D is the outer diameter of the shield machine, u is the shield machine excavation speed, ω is the cutterhead speed, q u is the uniaxial compressive strength of soil.

[0041] Preferably, in step S3, in the control of the speed of the shield machine outputting soil, the soil is discharged by the screw conveyor, and the discharge amount needs to be controlled to maintain the volume balance of the cut soil amount and the discharge amount. When the shield machine advances for each length L, the volume of the cut soil amount is:

[0042]

[0043] Where D is the diameter of the shield machine;

[0044] The weight of the soil removed is:

[0045] m1=ρ1V1;

[0046] Among them, ρ1 is the density of the cut soil;

[0047] According to the maximum and minimum values ​​of the density of the cut soil, the maximum and minimum values ​​of the cut soil weight can be obtained:

[0048] m 1max =ρ 1max V1;

[0049] m 1min =ρ 1min V1.

[0050] Preferably, in the control of the soil output speed, it is necessary to maintain a balance between the weight of the cut soil volume and the discharge soil volume; the shield machine needs to be injected with water during cutting, and the cut natural soil needs to be improved by adding an improver solution before discharge. When the shield machine advances for a length of K, the weight of the discharged soil volume is:

[0051] m2=m1+m3+m4;

[0052] Then the maximum and minimum values ​​of discharged soil are obtained as follows:

[0053] m 2max =m 1max +m3+m4;

[0054] m 2min =m 1min +m3+m4;

[0055] Among them, m3 is the weight of the improver solution, which is an empirical value; m4 is the amount of water used during cutting, which is an empirical value;

[0056] Volume of discharged soil:

[0057]

[0058] The maximum and minimum values ​​of the volume of discharged soil are:

[0059]

[0060] Among them, ρ2 is the density of the discharged soil, which can be measured;

[0061] When the shield machine advances a distance L, the amount of soil discharged is controlled at V 2min and V 2max Within the range, when the amount of discharged soil is less than V 2min When the amount of soil discharged is greater than V 2max When the speed of the shield machine is too fast or the speed of the screw machine is too fast.

[0062] Preferably, the grouting speed is ensured to be synchronous with the grouting of the equal tunnel segments while the shield is being machined.

[0063] Preferably, in step S4, the shield zoning control is divided into multiple hydraulic zones according to multiple groups of oil cylinders at the cutter head end of the shield machine, and each group is provided with a stroke sensor to perform separate pressure control so that the cutter head end of the shield machine is in an upward forward posture.

[0064] Compared with the prior art, the advantages of the present invention are:

[0065] (1) In the present invention, the required shield thrust can be calculated by calculating the soil bin pressure, and can be continuously optimized and adjusted during the excavation process to maintain the dynamic balance and stability of the pressure in the soil bin;

[0066] The tunneling speed is controlled by the thrust of the shield machine and the torque of the cutter head. In accordance with the relationship between the amount of soil discharged and the amount of cutting, the various working state parameters of the shield machine can be optimized according to the actual geological conditions and the state of soil discharged during the actual tunneling process, so that the tunneling speed, the thrust of the shield machine, the torque of the cutter head and the transmission of the screw machine can maintain a dynamic balance, thereby ensuring the micro-disturbance control of tunneling.

[0067] (2) In terms of shield machine posture control, shield zone control is used to keep the cutter head of the shield machine in a slightly upward excavation trend to avoid the shield machine from falling headward due to its own weight, which may cause the shield machine posture to lose control; the shield machine posture is adjusted and corrected by adjusting the different propulsion speeds and pressures of each group of cylinders; and the method of forward and reverse rotation of the cutter head is used to correct the rolling of the shield. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0069] Figure 1 This is a flow chart of the control method of the present invention;

[0070] Figure 2 This is a schematic diagram of the shield type soil pressure structure of the present invention. DETAILED DESCRIPTION

[0071] The present invention is further described in detail below in conjunction with specific embodiments:

[0072] As shown in the figure, the present invention is applied to shield tunneling technology. When tunneling in a cement-rich rock formation with developed fissures, the purpose of reducing the impact on stratum settlement during tunneling is achieved through theoretical calculation of soil bin pressure, shield thrust, propulsion speed, etc. and adjustment of shield posture. Specifically, a shield tunneling micro-disturbance control method includes the following steps:

[0073] S1. Calculate the soil bin pressure, which is obtained by the sum of the lateral horizontal loosening pressure, groundwater pressure and the set preparatory pressure. If the soil pressure is too small, it will cause large settlement deformation; if the soil pressure value is set too large, the stratum will rise, the shield thrust and cutter torque will increase, the excavation speed will slow down, the difficulty of slag improvement will increase, and the shield construction in the fissure-developed cement rock stratum will be more prone to soil bin or cutterhead mud cake phenomenon, and the disturbance of the stratum by shield excavation will become greater. The soil bin pressure is mainly achieved by maintaining the balance between the excavation volume and the discharge volume. The purpose of maintaining the soil bin pressure is achieved by setting the excavation speed and adjusting the discharge volume or setting the discharge volume and adjusting the excavation speed.

[0074] First, according to the determination method of deep and shallow buried tunnels, the calculated tunnel is determined to be a deep buried tunnel or a shallow buried tunnel. The boundary depth between deep and shallow buried tunnels is usually 2 to 2.5 times the average height of the construction collapse. This calculation and determination method is a prior art and will not be repeated in this embodiment. This embodiment takes a deep buried tunnel as an example:

[0075] The lateral horizontal loosening pressure P1 is:

[0076]

[0077] Where P0 = 0.45 × 2 6-s γw;

[0078] w=1+i(B-5);

[0079] Therefore, P1 = (0.45 × 2 6-s γ(1+i(B-5)));

[0080] Among them, S is the surrounding rock type, which can be obtained by looking up the table according to the current "Railway Tunnel Design Code", B is the net width of the tunnel (m), i is the rate of increase or decrease of surrounding rock pressure when B increases or decreases by 1m based on B=5m, when B<5m, i=0.2, B>5m, i=0.1.

[0081] The stratum generates vertical pressure as well as lateral pressure. The calculation of lateral horizontal loosening pressure P1 is shown in Table 1-1 below:

[0082] 1-1 Lateral horizontal loosening pressure

[0083]

[0084] Calculation of groundwater pressure P2:

[0085] 1) When the shield machine stops, due to the existence of pressure head difference in the stratum, groundwater will inevitably flow into the soil bin until the head pressure in the stratum is eliminated. The water pressure at this time is:

[0086] P2 = qγh;

[0087] Where: q is an empirical value determined based on the permeability coefficient of the soil; γ is the bulk density of water, γ = 10kN / m3; h is the height of the groundwater level from the top of the cutterhead.

[0088] 2) In actual construction, since groundwater in the pipe may form a water channel along the gaps outside the pipe segments, a certain pressure head will be formed when the shield is shut down for a long time.

[0089] P 2实际 =q1γh;

[0090] Where q1 is an empirical value determined by the permeability coefficient of the mortar and the degree of grouting fullness, generally ranging from 0.8 to 1.0; h is the height difference between the reinforcement grouting point and the top of the cutter head.

[0091] The groundwater pressure is P2 and P 2实际 The larger value of the two, in this embodiment, P2>P 2实际 Take this as an example to obtain the value.

[0092] Preparation pressure P 备 for:

[0093] Due to uncertain factors that may occur during construction, the construction soil pressure is less than the static soil pressure in the original soil. The value of soil pressure is usually based on theoretical calculations and takes into account a preliminary pressure of 10 to 20 kPa.

[0094] Based on the above calculations, the set soil bin pressure P is:

[0095] P=P1+P2+P 备 ;

[0096] In actual experience, in order to maintain the stability of the excavation face, the set soil bin pressure value can be slightly larger than the calculated soil bin pressure value P. By comparing the actual soil pressure value Pi in the shield soil bin with the set soil pressure value, the balance between the two is taken as the control target, and soil discharge management is carried out according to this pressure difference.

[0097] S2. Calculate the shield thrust and cutter torque. The shield thrust is obtained by the front soil pressure of the shield equipment and the friction of the soil on the side; the cutter torque includes the friction torque between the cutter and the soil, the formation resistance and the torque generated by the cutter.

[0098] When the shield advances, the main body of the shield gradually sinks into the soil, and its thrust gradually increases. The calculation method of the shield thrust is:

[0099] The positive soil pressure is:

[0100]

[0101] The friction force of the soil on the side of the shield equipment is:

[0102]

[0103] Among them, P e is the pressure on the shield machine, P e =γH+P0;

[0104] P1 is the lateral water and soil pressure at the top of the shield machine, P1 = P e K0;

[0105] P2 is the lateral water and soil pressure at the bottom of the shield machine, P2 = (P1 + γH) K0;

[0106] P 01 is the uniform pressure at the bottom of the shield machine,

[0107] Among them, G is the weight of the shield machine, D is the outer diameter of the shield machine, l is the length of the shield machine, and u is the friction coefficient between the shield and the soil;

[0108] The thrust of the shield machine is: F = F1 + F2 + F3;

[0109] Among them, F3 is the friction resistance of the matching trailer, which is an empirical value.

[0110] The friction torque between the cutterhead and the soil includes the friction resistance torque T1 between the front of the cutterhead and the soil; the friction resistance torque T2 between the back of the cutterhead and the soil in the pressure chamber; the torque generated by the formation resistance and the tool is T3, so the cutterhead torque is:

[0111] T = T1 + T2 + T3;

[0112] in,

[0113] T2 = W1μ1r;

[0114]

[0115] Where K0 is the lateral earth pressure coefficient, f is the friction factor between the cutterhead and the soil, γ is the gravity density of the soil, H is the tunnel depth (m), η is the cutterhead opening ratio of the shield machine, W1 is the cutterhead mass, μ1 is the cutterhead coefficient, r is the cutterhead radius, D is the outer diameter of the shield machine, u is the shield machine excavation speed, ω is the cutterhead speed, q u is the uniaxial compressive strength of soil.

[0116] On the basis of the pressure balance of the soil bin, the thrust of the shield and the torque of the cutterhead are set to reduce the disturbance caused by the shield tunneling to the surrounding strata.

[0117] S3. Calculate the advancement speed. Factors affecting the advancement speed include the speed at which the shield machine outputs soil, the grouting speed, and the grease injection speed at the shield tail.

[0118] During the shield tunneling process, the screw conveyor soil discharge system carries out soil discharge operations corresponding to the shield advancement, always maintaining a balance between the amount of soil cut and the amount of soil discharged to maintain the soil pressure in the bin. The pressure in the soil bin counteracts the soil pressure and water pressure of the working face to maintain the stability of the soil at the working face, prevent the collapse of the working face and the outflow of groundwater, so that the shield machine can dig in the surrounding rock without loosening, ensure that no stratum loss occurs, and realize the earth pressure balance excavation mode. When the soil bin pressure is balanced, stable and not over-excavated, the amount of soil discharged per ring (segment width L) is equal to the amount of earth excavated by each ring of the cutter disc. The volume of soil cut is:

[0119]

[0120] Where D is the diameter of the shield machine;

[0121] The weight of the soil removed is:

[0122] m1=ρ1V1;

[0123] Among them, ρ1 is the density of the cut soil;

[0124] According to the maximum and minimum values ​​of the density of the cut soil, the maximum and minimum values ​​of the cut soil weight can be obtained:

[0125] m 1max =ρ 1max V1;

[0126] m 1min =ρ 1min V1.

[0127] In the control of soil output speed, it is necessary to maintain a balance between the weight of the cut soil and the amount of soil discharged; the shield machine needs to be injected with water during cutting, and the cut natural soil needs to be improved by adding an improver solution before discharging the soil. When the shield machine advances for each length L, the weight of the discharged soil is:

[0128] m2=m1+m3+m4;

[0129] Then the maximum and minimum values ​​of discharged soil are obtained as follows:

[0130] m 2max =m 1max +m3+m4;

[0131] m 2min =m 1min +m3+m4;

[0132] Among them, m3 is the weight of the improver solution, which is an empirical value; m4 is the amount of water used during cutting, which is an empirical value;

[0133] Volume of discharged soil:

[0134]

[0135] The maximum and minimum values ​​of the volume of discharged soil are:

[0136]

[0137] Among them, ρ2 is the density of the discharged soil, which can be measured;

[0138] When the shield machine advances a distance L, the amount of soil discharged is controlled at V 2min and V 2max Within the range, when the amount of discharged soil is less than V 2min When the amount of soil discharged is greater than V 2max When the speed of the shield machine is too fast or the speed of the screw machine is too fast.

[0139] In this embodiment, shield earth removal adopts dual control indicators of weight and volume to control the stratum loss, which is generally not more than 3%, so as to achieve the purpose of balancing the amount of soil cut and the amount of earth removed.

[0140] In the control of grouting rate, for synchronous grouting, the synchronous grouting speed and the advancing speed are kept synchronized, that is, sufficient grouting is carried out while the shield machine is advancing. Synchronous grouting adopts dual control of grouting pressure and grouting volume, with grouting volume control as the main method to ensure that the filling behind the segment is dense and avoid soil disturbance.

[0141] Among them, the grouting volume is the amount of slurry required to fill the gap between the cut soil and the outer wall of the segment.

[0142] Grouting volume: Based on empirical formula calculations and previous shield construction experience, the grouting volume is 1.5 to 2 times the theoretical volume of the annular gap.

[0143] Theoretical grouting volume V = π(D2-d2)L / 4;

[0144] Theoretical grouting volume Q = (1.5 ~ 2.0) V;

[0145] Where: D is the cutter head diameter, d is the outer diameter of the segment, and L is the segment width.

[0146] The synchronous grouting pressure is set so that the pressure at the pressure inlet is greater than the sum of the static water pressure and soil pressure at that point. If the grouting pressure is too high, the soil layer outside the segment will be disturbed by the slurry, causing the ground to bulge and easily cause leakage from the shield tail; if the grouting pressure is too low, the slurry filling speed is too slow, the filling is insufficient, and the surface will sink and cause segment displacement.

[0147] S4. Shield posture control: Shield posture control is a dynamic adjustment process. The more unstable the shield posture is and the greater the deviation correction adjustment range is, the greater the disturbance caused by shield construction will be. It mainly includes shield zoning control, serpentine deviation correction and rolling control.

[0148] Shield zoning control is based on multiple groups of oil cylinders at the cutter head of the shield machine, which are divided into multiple hydraulic zones. Each group is equipped with a stroke sensor for separate pressure control, so that the cutter head of the shield machine is in an upward forward posture. During the shield excavation process, it is necessary to strictly control the shield posture to advance smoothly according to different geological conditions and horizontal and vertical curves of the line, reduce the serpentine value and rolling, and achieve the purpose of controlling the disturbance of shield construction. When rolling occurs, the method of forward and reverse cutting disc is adopted to correct the shield posture.

[0149] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A shield tunneling micro-disturbance control method, characterized in that: The following steps are involved: S1. Calculate the soil bin pressure, which is obtained by the sum of the lateral horizontal loosening pressure, the groundwater pressure and the set preparation pressure, and can be adjusted according to the amount of soil cut and the amount of soil discharge; S2, calculating the shield thrust and cutter head torque, wherein the shield thrust is obtained by the front soil pressure of the shield equipment and the friction of the soil on the side; the cutter head torque includes the friction torque between the cutter head and the soil, the formation resistance and the torque generated by the cutter; S3, calculating the advancement speed, wherein the factors affecting the advancement speed include the speed at which the shield machine outputs soil, the grouting speed, and the grease injection speed at the shield tail; S4. Control of the shield posture. The control of the shield posture is a dynamic adjustment process, including shield zoning control, serpentine correction and rolling control.

2. A shield tunneling micro-disturbance control method according to claim 1, characterized in that: The calculation method of the soil bin pressure is: The lateral horizontal loosening pressure P1 is: Where P0 = 0.45 × 2 6-s γw; w=1+i(B-5); Therefore, P1 = (0.45 × 2 6-s γ(1+i(B-5))); Where, S is the surrounding rock type, which can be obtained by looking up the table in the current "Railway Tunnel Design Code", B is the net width of the tunnel (m), i is the rate of increase or decrease of surrounding rock pressure when B increases or decreases by 1m based on B=5m, when B<5m, i=0.2, B>5m, i=0.1; Calculation of groundwater pressure P2: P2 = qγh; Where: q is an empirical value determined based on the permeability coefficient of the soil; γ is the bulk density of water, γ = 10kN / m3; h is the height of the groundwater level from the top of the cutterhead. Based on the above calculations, the set soil bin pressure P is: P=P1+P2+P 备 ; Where P 备 is the set reserve pressure.

3. A shield tunneling micro-disturbance control method according to claim 2, characterized in that: When the shield advances, the main body of the shield gradually sinks into the soil, and its thrust gradually increases. The calculation method of the shield thrust is: The positive soil pressure is: The friction force of the soil on the side of the shield equipment is: Among them, P e is the pressure on the shield machine, P e =γH+P0; P1 is the lateral water and soil pressure at the top of the shield machine, P1 = P e K0; P2 is the lateral water and soil pressure at the bottom of the shield machine, P2 = (P1 + γH) K0; P 01 is the uniform pressure at the bottom of the shield machine, Among them, G is the weight of the shield machine, D is the outer diameter of the shield machine, l is the length of the shield machine, and u is the friction coefficient between the shield and the soil; The thrust of the shield machine is: F = F1 + F2 + F3; Among them, F3 is the friction resistance of the matching trailer, which is an empirical value.

4. A shield tunneling micro-disturbance control method according to claim 3, characterized in that: The friction torque between the cutter head and the soil includes the friction resistance torque T1 between the front of the cutter head and the soil; the friction resistance torque T2 between the back of the cutter head and the soil in the pressure chamber; the torque generated by the formation resistance and the cutter is T3, then the cutter head torque is: T = T1 + T2 + T3; in, T2 = W1μ1r; Where K0 is the lateral earth pressure coefficient, f is the friction factor between the cutterhead and the soil, γ is the gravity density of the soil, H is the tunnel depth (calculated to the center of the tunnel) (m), η is the cutterhead opening ratio of the shield machine, W1 is the cutterhead mass, μ1 is the cutterhead coefficient, r is the cutterhead radius, D is the outer diameter of the shield machine, u is the shield machine excavation speed, ω is the cutterhead speed, q u is the uniaxial compressive strength of soil.

5. A shield tunneling micro-disturbance control method according to claim 4, characterized in that: In step S3, in the control of the speed of the shield machine's output soil, the screw conveyor is used to discharge soil, and the discharge volume needs to be controlled to maintain the volume balance between the amount of cut soil and the amount of discharge soil. When the shield machine advances for each length L, the volume of the cut soil is: Where D is the diameter of the shield machine; The weight of the soil removed is: m1=ρ1V1; Among them, ρ1 is the density of the cut soil; According to the maximum and minimum values ​​of the density of the cut soil, the maximum and minimum values ​​of the cut soil weight can be obtained: m 1max =ρ 1max V1; m 1min =ρ 1min V1.

6. A shield tunneling micro-disturbance control method according to claim 5, characterized in that: In the control of soil output speed, it is necessary to maintain a balance between the weight of the cut soil and the amount of soil discharged; the shield machine needs to be injected with water during cutting, and the cut natural soil needs to be improved by adding an improver solution before discharging the soil. When the shield machine advances for each length L, the weight of the discharged soil is: m2=m1+m3+m4; Then the maximum and minimum values ​​of discharged soil are obtained as follows: me 2max =m 1max +m3+m4; me 2min =m 1min +m3+m4; Among them, m3 is the weight of the improver solution, which is an empirical value; m4 is the amount of water used during cutting, which is an empirical value; Volume of discharged soil: The maximum and minimum values ​​of the volume of discharged soil are: Among them, ρ2 is the density of the discharged soil, which can be measured; When the shield machine advances a distance L, the amount of soil discharged is controlled at V 2min and V 2max Within the range, when the amount of discharged soil is less than V 2min When the amount of soil discharged is greater than V 2max When the speed of the shield machine is too fast or the speed of the screw machine is too fast.

7. A shield tunneling micro-disturbance control method according to claim 6, characterized in that: The grouting speed is ensured to be synchronous with the grouting of the equal tunnel segments while the shield is being machined.

8. The shield tunneling micro-disturbance control method according to claim 1, characterized in that: In step S4, the shield machine zoning control is divided into multiple hydraulic zones according to multiple groups of oil cylinders at the cutter head end of the shield machine, and each group is provided with a stroke sensor to perform separate pressure control so that the cutter head end of the shield machine is in an upward forward posture.

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