A method and system for judging soil pressure balance shield gushing under the action of cutterhead excavation vibration load

Abstract

The application provides a soil pressure balance shield gushing judgment method and system under the action of a cutter head excavation vibration load. The soil pressure balance shield gushing judgment method under the action of the cutter head excavation vibration load comprises the following steps: a vibration pore pressure model of a soil pressure balance shield under the action of a cutter head excavation vibration load is established based on a one-dimensional consolidation method; wherein the vibration pore pressure model is used to characterize the vibration pore pressure growth of the soil pressure balance shield under the action of the cutter head excavation vibration load; and the pore water pressure in the soil layer at any time t is determined based on an eigenfunction method according to the vibration pore pressure model. In this way, the gushing of the soil body is judged based on the pore pressure condition of the dynamic load with time growth.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shield construction, in particular to a method and system for judging soil pressure balance shield gushing under the action of cutter head tunneling vibration load. BACKGROUND

[0002] Soil pressure balance shield gushing is closely related to the pore pressure at the rear gate of the screw conveyor. When the pore pressure at the rear gate of the screw conveyor is too large, gushing will occur, causing mud to spew out and the shield to be unable to tunnel normally.

[0003] Gushing will seriously affect the construction environment in the connecting bridge area, and even the shield tail and the entire trolley working range. This will inevitably cause downtime during construction, and the spoil must be cleaned up manually, which is time-consuming. Secondly, when the shield machine stops tunneling and closes the screw conveyor discharge gate, the mud in the soil bin quickly fills the entire screw conveyor. Once the gate is reopened, gushing will occur again. This will form a vicious cycle, slowing down the tunneling speed, and the shield tail spoil cleaning time is very long, which seriously affects the progress of shield construction. Thirdly, due to the inability to effectively control the actual amount of earthwork during gushing, it is difficult to establish a true soil pressure balance during shield advancement, thereby increasing the disturbance to the stratum and even causing ground subsidence and other secondary disasters.

[0004] Currently, research on gushing disasters at home and abroad mainly focuses on the prevention and improvement of gushing. From the perspective of one-dimensional statics, the influence of shield construction load on the distribution of pore water pressure in the bottom layer is considered, a soil pressure balance shield pressure cabin and screw conveyor integrated model is established, and the conditions for gushing are analyzed, but the change in water pressure distribution in the pressure cabin and screw conveyor under the action of cutter head tunneling vibration load is not considered, and the calculation of pore pressure on the tunneling face during tunneling under the action of cutter head tunneling vibration load is not considered.

[0005] Therefore, it is necessary to provide an improved technical solution to address the deficiencies of the prior art. SUMMARY

[0006] The purpose of the present application is to provide a method and system for judging soil pressure balance shield gushing under the action of cutter head tunneling vibration load to solve or alleviate the problems existing in the prior art.

[0007] In order to achieve the above purpose, the present application provides the following technical solution:

[0008] The application provides a method for judging soil pressure balance shield gushing under the action of cutterhead tunneling vibration load, comprising the following steps: S101, a vibration pore pressure model of the soil pressure balance shield under the action of the cutterhead tunneling vibration load is established based on a one-dimensional consolidation method; wherein the vibration pore pressure model is used for characterizing the vibration pore pressure growth of the soil pressure balance shield under the action of the cutterhead tunneling vibration load, and the vibration pore pressure model is:

[0009]

[0010] wherein the tunneling face is taken as a zero point, x represents the distance from the tunneling face of the shield tunneling machine, μ represents the pore water pressure in the soil layer, μ(x, t) represents the pore water pressure at the x distance from the tunneling face of the shield tunneling machine at the t moment; C v represents the consolidation coefficient of the soil layer; γ w represents the unit weight of water; and L is the total length of the shield tunneling machine. represents the muck water head distribution of the soil pressure balance shield in a static state; μ g represents the rise of the pore pressure vibration of the saturated sand soil under the undrained condition; f is the vibration frequency of the cyclic load; and T is the vibration period of the cyclic load; σ' c is the soil bin pressure, and a and b are fitting parameters related to the dynamic load, frequency and soil bin pressure of the tunneling face; S102, the pore water pressure in the soil layer at any moment t is determined according to the vibration pore pressure model based on the eigenfunction method.

[0011] Preferably, in step S101, the muck water head distribution is:

[0012]

[0013] wherein Q is the water flow in the soil pressure bin, L1 is the length of the pressure cabin, L is the total length of the shield tunneling machine, A1 is the cross-sectional area of the pressure cabin, A2 is the cross-sectional area of the screw soil discharger, H1 is the water head height of the pressure tube at the front end of the pressure cabin, H2 is the water head height of the pressure tube at the outlet of the soil discharger, θ is the installation inclination angle of the screw soil discharger, and k is the permeability coefficient of the muck of the shield tunneling machine.

[0014] Preferably, step S102 comprises: the pore water pressure in the soil layer at any moment t is determined according to the vibration pore pressure model based on a preset eigenfunction set; wherein the eigenfunction set is:

[0015]

[0016] correspondingly,

[0017]

[0018] the pore water pressure μ(x, t) in the soil layer at any moment t is obtained.

[0019] Preferably, the earth pressure balance shield gushing judgment method under the cutter head tunneling vibration load further comprises: determining the water flow Q in the earth pressure balance shield machine under the tunneling state according to the average advancing speed and the pressure cabin diameter of the earth pressure balance shield machine, and the porosity of the excavated soil body.

[0020] Preferably, the porosity e0 of the excavated soil body is 0.5.

[0021] Preferably, in step S101, the permeability coefficient k of the excavated soil of the shield machine is 1*10 -6 cm / s; the consolidation coefficient C v of the soil layer is 0.102 cm 2 / s.

[0022] Preferably, the earth chamber pressure σ' c is 100 kPa, the vibration frequency f of the cyclic load is 1 hz, a is 3.304, and b is 0.28.

[0023] The embodiment of the application further provides a shield gushing judgment system under the cutter head tunneling vibration load, comprising: a model establishing unit configured to establish a vibration pore pressure model of the earth pressure balance shield under the cutter head tunneling vibration load based on a one-dimensional consolidation method; wherein the vibration pore pressure model is used to characterize the vibration pore pressure growth of the earth pressure balance shield under the cutter head tunneling vibration load, and the vibration pore pressure model is:

[0024]

[0025] wherein the tunneling face is taken as a zero point, x represents the distance from the tunneling face of the shield machine, μ represents the pore water pressure in the soil layer, μ(x, t) represents the pore water pressure in the soil layer at the x distance from the tunneling face of the shield machine at the t moment; C v represents the consolidation coefficient of the soil layer; γ w represents the unit weight of water; L is the total length of the shield machine; represents the slurry water head distribution of the earth pressure balance shield in the static state; μ g represents the rise of the pore pressure vibration of the saturated sand soil under the undrained condition; f is the vibration frequency of the cyclic load; T is the vibration period of the cyclic load; σ' c is the earth chamber pressure, and a and b are fitting parameters related to the dynamic load, the frequency and the earth chamber pressure of the tunneling face;

[0026] A pore water pressure unit is configured to determine the pore water pressure in the soil layer at any moment t based on the vibration pore pressure model according to the eigenfunction method.

[0027] Beneficial effects:

[0028] The earth pressure balance shield tunneling blowout judgment technology under cutterhead tunneling vibration load provided in this application embodiment firstly establishes a vibration pore pressure model of the earth pressure balance shield tunneling machine under static state with the distribution of slag and soil water head under cutterhead tunneling vibration load based on a one-dimensional consolidation method; then, based on the eigenfunction method, the pore water pressure in the soil layer at any time t under cutterhead vibration load is determined according to the vibration pore pressure model. Thus, the pore pressure situation as the dynamic load increases over time provides a basis for judging soil blowout. Attached Figure Description

[0029] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein:

[0030] Figure 1 This is a flowchart illustrating a method for determining blowout in earth pressure balance shield tunneling under the action of cutterhead tunneling vibration load, according to some embodiments of this application.

[0031] Figure 2 This is a schematic diagram illustrating the principle of soil and water head distribution in a static state of an earth pressure balance shield tunneling machine according to some embodiments of this application.

[0032] Figure 3 This is a schematic diagram comparing the pore water pressure obtained from the vibration pore pressure model at time t=0 with the pore pressure value under the initial conditions of the earth pressure balance shield tunnel in a specific embodiment of this application.

[0033] Figure 4 for Figure 3 Diagram of pore pressure variation at the discharge port obtained under the initial conditions of the embodiment;

[0034] Figure 5 This is a structural schematic diagram of an earth pressure balance shield tunneling blowout detection system under the action of cutterhead tunneling vibration load, according to some embodiments of this application. Detailed Implementation

[0035] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. In fact, those skilled in the art will recognize that modifications and variations can be made to the present application without departing from the scope or spirit thereof. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the present application encompass such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0036] Figure 1A flowchart of a method for judging a soil pressure balance shield gushing under the action of a cutterhead excavation vibration load according to some embodiments of the present application is shown in the figure; Figure 2 A principle diagram of a muck water head distribution of a soil pressure balance shield in a static state according to some embodiments of the present application is shown in the figure; Figure 1 、 Figure 2 As shown in the figure, the method for judging a soil pressure balance shield gushing under the action of a cutterhead excavation vibration load includes the following steps: S101, a vibration pore pressure model of a soil pressure balance shield under the action of a cutterhead excavation vibration load is established based on a one-dimensional consolidation method; wherein the vibration pore pressure model is used to characterize the vibration pore pressure growth of the soil pressure balance shield under the action of the cutterhead excavation vibration load, and the vibration pore pressure model is shown in formula (1), which is as follows:

[0037]

[0038] wherein the excavation face is taken as a zero point, x represents a distance from the excavation face of the shield machine, μ represents a pore water pressure in the soil layer; μ (x, t) represents the pore water pressure in the soil layer at a distance x from the excavation face of the shield machine at time t; C v represents a consolidation coefficient of the soil layer; γ w represents a unit weight of water; and L is a total length of the shield machine. represents a muck water head distribution of a soil pressure balance shield in a static state; μ g represents an increase of a pore pressure vibration of saturated sand under undrained conditions, that is, a pore water pressure increase of a soil body in the shield machine under the action of a cyclic vibration load under the undrained conditions of the saturated sand; f is a vibration frequency of the cyclic load; T is a vibration period of the cyclic load; σ′ c is a soil chamber pressure, and a and b are parameters related to a dynamic load, a frequency and the soil chamber pressure of the excavation face. Here, it should be noted that the cyclic load is a vibration load during cutterhead excavation, and the vibration frequency is measured in the field during the excavation of the soil pressure balance shield. The vibration frequency and the vibration period are inversely related to each other. N1 is an influence parameter related to the vibration frequency f in the vibration pore pressure model.

[0039] In the embodiments of the present application, a and b are fitting parameters, which are affected by the dynamic load, the frequency and the soil chamber pressure; by taking the soil body in the field, using a high-frequency vibration triaxial apparatus, and performing a simulation test according to the vibration frequency, the dynamic load and the soil chamber pressure measured in the field, data of a change of the pore water pressure in the soil body with time are obtained, and a and b are obtained after nonlinear fitting using the data and μ g .

[0040] Specifically, the vibration load P of the cutter head during tunneling is monitored by a vibration sensor, according to the soil vibration liquefaction characteristic experiment, the liquefaction time t' (maximum vibration pore pressure) of the experimental soil sample during liquefaction and a plurality of data (f, t') of the vibration frequency f and the liquefaction time t' are obtained, and then t' = 10 a f b-1 The plurality of data (f, t') is fitted to obtain the fitting parameters a and b.

[0041] During the tunneling process of the shield machine, the jacking force of the tunneling face of the shield machine is large and the drainage of the soil discharge port is not smooth, which can be regarded as undrained, and for the soil in the shield machine at this time, affected by the tunneling vibration, the pore water pressure in the soil will rise, and when the pore pressure rises to a certain extent, there is a risk of gushing. Therefore, based on the one-dimensional saturated consolidation method of soil mechanics, a vibration pore pressure model of the pore water pressure in the shield under the action of the cutter head tunneling vibration load under the condition of the slurry water head distribution of the shield in the static state is established, and the vibration pore pressure growth of the earth pressure balance shield under the action of the cutter head tunneling vibration load is described.

[0042] The water body in the shield machine in the static state obeys Darcy's law, and the slurry water head distribution of the earth pressure balance shield in the static state is established; in step S101, the slurry water head distribution is shown in formula (2), and formula (2) is as follows:

[0043]

[0044] Wherein, Q is the water flow in the earth pressure chamber, L1 is the length of the pressure tank, L is the total length of the shield machine, A1 is the cross-sectional area of the pressure tank, A2 is the cross-sectional area of the spiral soil discharger, H1 is the water head height of the pressure tube at the front end of the pressure tank, H2 is the water head height of the pressure tube at the outlet of the soil discharger, θ is the installation inclination angle of the spiral soil discharger, and k is the permeability coefficient of the shield machine for excavating slurry.

[0045] In the embodiment of the application, the soil in the shield machine is simulated by the slurry water head distribution of the earth pressure balance shield; the pressure tube is installed at the front end of the pressure tank and the outlet of the soil discharger respectively, so as to monitor the water head height H1 of the pressure tube at the front end of the pressure tank and the water head height H2 of the pressure tube at the outlet of the soil discharger.

[0046] Step S102, based on the eigenfunction method, the pore water pressure in the soil layer at any time t is determined according to the vibration pore pressure model.

[0047] In the embodiment of the present application, the drainage port of the screw conveyor of the earth pressure balance shield is a water-impermeable boundary, an intrinsic function set is selected according to the water-impermeable boundary condition, and then the change rule of the pore water pressure is determined according to the vibration pore pressure model. Specifically, based on the preset intrinsic function set, the pore water pressure in the soil layer at any time t is determined according to the vibration pore pressure model.

[0048] wherein the intrinsic function set is shown in formula (3), and formula (3) is as follows:

[0049]

[0050] wherein μ (x, t) and According to the expansion of the intrinsic function set, the change rule of the pore water pressure is shown in formula (4), and formula (4) is as follows:

[0051]

[0052] wherein n = 0, g n (0) represents the pore water pressure at t = 0; n = 1, 2, 3, …, g n (0) represents the speed of the pore water pressure mutation, and the greater the value, the faster the speed of the pore water pressure mutation.

[0053] Here, it should be noted that g n (0) is influenced by the water flow Q in the earth pressure chamber, the length L1 of the pressure tank, the total length L of the shield machine, the cross-sectional area A1 of the pressure tank, the cross-sectional area A2 of the screw earth discharger, the water head height H1 of the pressure tube at the front end of the excavation surface of the pressure tank, the water head height H2 of the pressure tube at the outlet of the earth discharger, the installation angle θ of the screw earth discharger, and the permeability coefficient k of the shield machine for excavating the spoil. Among them, the water flow Q in the earth pressure chamber, the water head height H1 of the pressure tube at the front end of the excavation surface of the pressure tank, and the water head height H2 of the pressure tube at the outlet of the earth discharger are in a proportional relationship with the speed g n (0) of the pore water pressure mutation; the length L1 of the pressure tank, the total length L of the shield machine, the installation angle θ of the screw earth discharger, and the permeability coefficient k of the shield machine for excavating the spoil are in an inverse proportional relationship with the speed g n (0) of the pore water pressure mutation.

[0054] In a specific example, the initial conditions for the judgment of the gushing of the earth pressure balance shield under the action of the cutter head driving vibration load are shown in Table 1, and Table 1 is as follows:

[0055]

[0056] Table 1

[0057] In the embodiments of the present application, the change rule of the pore water pressure when n=0 (formula (4)) is calculated, and the pore water pressure when n=0 is as shown in formula (5), and formula (5) is as follows:

[0058]

[0059] The change rule of the pore water pressure when n=1, 2, 3, … is calculated, and the pore water pressure when n=1, 2, 3, … is as shown in formula (6), and formula (6) is as follows:

[0060]

[0061] The soil pressure balance shield static state under the muck water head distribution Substituting formula (5) and formula (6), formula (7) and formula (8) are obtained respectively, and formula (7) and formula (8) are as follows:

[0062]

[0063]

[0064] Further, the summation of n=0 and n=1, 2, 3, … is calculated, and the pore water pressure in the soil pressure chamber under the one-dimensional model is as shown in formula (9), and formula (9) is as follows:

[0065]

[0066] That is, the pore water pressure μ(x, t) in the soil layer at any time t.

[0067] Further, through the pore water pressure in the shield machine at different times, the spouting that may occur when the jacking force of the jacking face of the shield machine is large and the soil discharge port is not smooth is predicted.

[0068] In some optional embodiments, the soil pressure balance shield spouting judgment method under the action of the cutter head excavation vibration load further includes: determining the water flow Q in the soil pressure chamber of the soil pressure balance shield machine in the jacking state according to the average jacking speed and the pressure chamber diameter of the soil pressure balance shield machine, and the porosity of the excavated soil.

[0069] In the embodiments of the present application, the water flow in the soil pressure chamber of the soil pressure balance shield machine in the jacking state is determined according to formula (10), and formula (10) is as follows:

[0070] Q=e0A1V………………………………(10)

[0071] Wherein, V represents the average jacking speed of the soil pressure balance shield machine.

[0072] In a specific example, the average advance speed of the earth pressure balance shield tunneling machine is V = 12 m / day, the diameter of the pressure chamber is D1 = 6 m, and the porosity of the excavated soil is e0 = 0.5. From formula (10), the water delivery volume (water flow rate in the earth pressure chamber) of the earth pressure balance shield tunneling machine during tunneling can be obtained as Q = 1.98 (cm³). 3 / s). Here, porosity e0 represents the volume ratio of the entire transported soil in the pore water station. The porosity of the excavated soil was obtained through on-site measurement.

[0073] In another specific example, the permeability coefficient k of the excavated soil by the tunnel boring machine is 1 × 10⁻⁶. -6 cm / s; soil consolidation coefficient C v =0.102cm 2 / s. Furthermore, the earth pressure σ′ c =100KPa, the vibration frequency of the cyclic load is f=1HZ, and the parameters related to the dynamic load and frequency on the tunnel face are a=3.304 and b=0.28.

[0074] From formula (9), we can obtain a comparison between the pore water pressure obtained from the vibration pore pressure model at t=0 and the pore pressure value under the initial conditions of earth pressure balance shield tunneling, as follows: Figure 3 As shown; using the above initial conditions, the resulting diagram of pore pressure variation at the discharge outlet is as follows. Figure 4 As shown, when the drainage outlet is not draining, the water head at the drainage outlet will increase significantly in a short period of time. After that, as time goes on, the water head at the drainage outlet continues to increase steadily until the soil liquefies at about 420 minutes, at which point the pore pressure stops increasing.

[0075] The earth pressure balance shield tunneling gushing judgment technology under the action of cutterhead tunneling vibration load provided in this application embodiment takes into account the vibration load generated at the excavation face during the tunneling process, establishes the slag and water head distribution of the earth pressure balance shield tunneling screw conveyor during the tunneling process, and obtains the theoretical solution of pore pressure increasing with time under dynamic load through the seepage equation. Therefore, the pore pressure situation of dynamic load increasing with time provides a basis for judging soil gushing.

[0076] Figure 5 This is a structural schematic diagram of an earth pressure balance shield tunneling blowout detection system under cutterhead tunneling vibration load according to some embodiments of this application; as shown. Figure 5 As shown, the earth pressure balance shield tunneling blowout judgment system under cutterhead tunneling vibration load includes: a model building unit 501 and a pore water pressure unit 502. The model building unit 501 is configured to establish a vibration pore pressure model of the earth pressure balance shield tunneling under cutterhead tunneling vibration load based on a one-dimensional consolidation method. The vibration pore pressure model is used to characterize the increase in vibration pore pressure of the earth pressure balance shield tunneling under cutterhead tunneling vibration load. The vibration pore pressure model is as follows:

[0077]

[0078] wherein, taking the tunneling face as zero point, x represents the distance from the tunneling face of the shield machine, μ represents the pore water pressure in the soil layer, μ(x, t) represents the pore water pressure in the soil layer at the x distance from the tunneling face of the shield machine at the t moment; C v represents the consolidation coefficient of the soil layer; γ w represents the unit weight of water; L is the total length of the shield machine; represents the muck water head distribution of the earth pressure balance shield in the static state; μ g represents the rise of the pore pressure vibration of the saturated sand soil under the undrained condition; f is the vibration frequency of the cyclic load; T is the vibration period of the cyclic load; σ' c is the soil chamber pressure, and a and b are fitting parameters related to the dynamic load, frequency and soil chamber pressure borne by the tunneling face.

[0079] The pore water pressure unit 502 is configured to determine the pore water pressure in the soil layer at any moment t according to the vibration pore pressure model based on the eigenfunction method.

[0080] The cutter tunneling vibration load acting earth pressure balance shield gushing judgment system provided by the embodiments of the present application can implement the steps and processes of any one of the cutter tunneling vibration load acting earth pressure balance shield gushing judgment method embodiments described above, and achieve the same technical effects, and will not be repeated here.

[0081] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for determining a soil pressure balance shield gushing caused by a cutterhead excavation vibration load, characterized in that, Comprising: Step S101, based on one-dimensional consolidation method, the vibration pore pressure model of the soil pressure balance shield under the action of the cutterhead excavation vibration load is established; wherein, the vibration pore pressure model is used to characterize the vibration pore pressure growth of the soil pressure balance shield under the action of the cutterhead excavation vibration load, and the vibration pore pressure model is: ； wherein the face is taken as zero point, represents the distance from the face of the shield machine, represents the pore water pressure in the soil layer, represents the distance from the face of the shield machine, the pore water pressure at the time of ; represents the consolidation coefficient of the soil layer; represents the specific weight of water; is the total length of the shield machine; represents the muck water head distribution of the earth pressure balance shield in the static state; represents the rise of the pore water pressure of the soil in the shield machine under the action of the cyclic vibration load under undrained conditions of the saturated sand; is the vibration frequency of the cyclic load; is the vibration period of the cyclic load; is the soil chamber pressure, and are fitting parameters related to the vibration load, frequency and soil chamber pressure of the face. Step S102, based on the eigenfunction method, determining the pore pressure at any time t according to the vibration pore pressure model Pore water pressure in soil layer; In step S101, the muck water head distribution is: ； wherein, is the water flow rate in the earth pressure chamber, is the length of the pressure chamber, is the total length of the shield machine, is the cross-sectional area of the pressure chamber, is the cross-sectional area of the screw earth discharger, is the water head height of the piezometer tube at the front end of the excavation surface of the pressure chamber, is the water head height of the piezometer tube at the outlet of the earth discharger, is the installation inclination angle of the screw earth discharger, is the permeability coefficient of the shield machine excavation spoil. According to the average advancing speed of the earth pressure balance shield machine and the pressure cabin diameter, and the porosity of the excavated soil body, the water flow in the earth pressure balance shield machine in the tunneling state is determined .

2. The earth pressure balance shield gushing judgment method of cutterhead excavation vibration load action according to claim 1, characterized by, Step S102 includes: Based on a preset set of eigenfunctions, a vibration pore pressure model is determined according to the vibration pore pressure model at any time Pore water pressure in the soil layer; Wherein, the set of eigenfunctions is: ； Correspondingly, by ； obtaining an arbitrary time pore water pressure in the soil layer .

3. The earth pressure balance shield gushing judgment method of cutterhead excavation vibration load action according to claim 1, characterized in that, Porosity of excavated soil .

4. The earth pressure balance shield gushing judgment method of cutterhead excavation vibration load action according to claim 1, characterized by, In step S101, Permeability coefficient of excavated soil by shield machine ; consolidation coefficient of soil layer .

5. The cutterhead excavation vibration load acting on the soil pressure balance shield gushing judgment method according to claim 1, characterized in that, soil bin pressure vibration frequency of the cyclic load , ; .

6. A soil pressure balance shield gushing judgment system of a cutter head excavation vibration load, characterized in that, Comprising: The model establishing unit is configured to establish the vibration pore pressure model of the soil pressure balance shield under the action of the cutterhead excavation vibration load based on one-dimensional consolidation method; wherein, the vibration pore pressure model is used to characterize the vibration pore pressure growth of the soil pressure balance shield under the action of the cutterhead excavation vibration load, and the vibration pore pressure model is: ； wherein the face is taken as zero point, represents the distance from the face of the shield machine, represents the pore water pressure in the soil layer, represents the distance from the face of the shield machine the pore water pressure at the time of ; represents the consolidation coefficient of the soil layer; represents the specific weight of water; is the total length of the shield machine; represents the muck water head distribution of the earth pressure balance shield in the static state; represents the rise of the pore water pressure of the soil in the shield machine under the action of the cyclic vibration load under undrained conditions; is the vibration frequency of the cyclic load; is the vibration period of the cyclic load; is the soil chamber pressure, and is a fitting parameter related to the vibration load, frequency and soil chamber pressure on the face. A pore water pressure unit is configured to determine, at any time instant, the pore water pressure in the soil layer based on the eigenfunction method according to the vibrating pore pressure model pore water pressure in the soil layer; The muck water head distribution is: ； wherein, is the water flow rate in the earth pressure chamber, is the length of the pressure chamber, is the total length of the shield machine, is the cross-sectional area of the pressure chamber, is the cross-sectional area of the screw earth discharger, is the water head height of the piezometer tube at the front end of the pressure chamber, is the water head height of the piezometer tube at the outlet of the earth discharger, is the installation inclination angle of the screw earth discharger, is the permeability coefficient of the shield machine to excavate the earth. The water flow in the earth pressure balance shield machine in the tunneling state is determined according to the average advancing speed of the earth pressure balance shield machine, the pressure cabin diameter, and the porosity of the excavated soil body .

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