Method for determining influence of cutter head collision on soil body during shield civil engineering underground butt joint

Abstract

The application provides a method for determining the influence of cutter head collision on soil body when two shield machines are butt-jointed in earth, which comprises the following steps: (1) determining the rated torque M 1，max , 2，max of the cutter heads of the two shield machines, the diameters D1 and D2 of the cutter heads and the length L of the shield machines; (2) determining the position A (x0, y0) of the collision point of the two cutter heads; (3) determining the undrained shear strength c u of the soil body around the cutter heads; (4) determining the cutting torque M generated by the cutter heads on the soil body; (5) determining the maximum range of the influence of the deflection of the cutter heads on the soil body; (5-1) determining the central position B (x1, y1) of the rotating cutter head and the intersection C (x2, y2) of the peripheries of the two cutter heads; (5-2) determining the maximum range boundary generated by the cutter heads on the soil body; (6) determining the sectional area of the range of the influence of the cutter heads on the soil body, i.e. the area surrounded by the curve CGF and the curve CDEF; and (7) determining the volume of the influence of the whole shield machine on the surrounding soil body.

Description

TECHNICAL FIELD

[0001] The application relates to a method for determining the influence of cutter head collision on surrounding soil during shield civil engineering ground-in-ground butt joint. BACKGROUND

[0002] With the development of rail transit in China, the demand for tunnels has significantly increased, and the shield method is applied more and more widely. In order to solve the problems caused by construction conditions such as large-span, cross-sea tunnels, and the inability to set a working well in a densely populated urban area, the shield civil engineering ground-in-ground butt joint construction method is often used. Shield civil engineering ground-in-ground butt joint is a construction method in which two shield machines are pushed towards each other, and the cutter heads of the two shield machines are completely close to each other at the butt joint point, and the shield machines are disassembled in the hole. When the two shield machines are constantly approaching, the cutter heads of the two shield machines are prone to collision and deflection, thereby causing extrusion and cutting of the surrounding soil, which can seriously affect the quality and progress of the project. At present, there is no reliable method to determine the above problems. SUMMARY

[0003] The main technical problem to be solved by the application is to provide a method for determining the influence of cutter head collision on soil during shield civil engineering ground-in-ground butt joint, which is used to solve the problem that the cutter heads of two shield machines excavating towards each other collide due to carelessness when shield civil engineering ground-in-ground butt joint is used, and finally the shield machine deviates from the predetermined track and causes deformation of the surrounding soil.

[0004] In order to solve the above technical problems, the application provides a method for determining the influence of cutter head collision on soil during shield civil engineering ground-in-ground butt joint, which comprises the following steps:

[0005] (1) determining the rated torque M of the cutter heads of the two shield machines 1，max , M 2，max , the diameters D1, D2 of the cutter heads, and the length L of the shield machine;

[0006] (2) determining the position A(x0, y0) of the collision point of the two cutter heads;

[0007] (3) determining the undrained shear strength c of the soil around the cutter heads u ;

[0008] (4) determining the cutting torque M generated by the cutter heads on the soil;

[0009] (5) determining the maximum range of the influence of cutter head deflection on the soil;

[0010] (5-1) determining the center position B(x1, y1) of the rotating cutter head and the intersection point C(x2, y2) of the periphery of the two cutter heads;

[0011] (5-2) Determine the maximum range of the cutter head on the soil boundary, which is curve CE, EF; Curve CE is a part of a circle with B(x1, y1) as the center, curve EF is a part of a circle with A(x0, y0) as the center, a part of a circle with radius L;

[0012] (6) Determine the cross-sectional area of the cutter head affecting the soil, which is the area enclosed by curve CGF and curve CDEF;

[0013] The area enclosed by curve CGF and curve CDEF is calculated by the method of block integration, where point C is the intersection of the two cutter heads, point G is the intersection of the fixed cutter head 2 and the x-axis, point F is the starting point of the deflection, point D is the farthest point of the trajectory CDEF along the negative x-axis, and point E is the demarcation point of different expressions of the deflection trajectory of the deflection cutter head 1.

[0014] (7) Determine the volume of the entire shield machine affecting the surrounding soil.

[0015] In a preferred embodiment: In step 1, according to the selected shield machine model, the rated torques M 1，max , M 2，max of the two cutter heads of the shield machine are determined, as well as the diameters D1, D2 of the cutter heads and the length L of the shield machine.

[0016] In a preferred embodiment: In step 2, a rectangular coordinate system is established with the center of the tunnel cross section as the origin, the horizontal direction as the x-axis, the vertical direction as the y-axis, and the tunnel length direction as the z-axis; The position of the collision point A(x0, y0) of the two cutter heads is determined by geophysical prospecting.

[0017] In a preferred embodiment: In step 3, the undrained shear strength c u of the soil is determined by triaxial compression test.

[0018] In a preferred embodiment: Step 4 includes the following sub-steps:

[0019] (4-1) When one cutter head rotates and the other cutter head is stationary, the cutting torque of the cutter head on the soil is M = M 1，max ;

[0020] (4-2) When one cutter head rotates and the other cutter head rotates in the same direction, the cutting torque of the cutter head on the soil is M = M 1，max + M 2，max ;

[0021] (4-3) When one cutter head rotates and the other cutter head rotates in the opposite direction, the cutting torque of the cutter head on the soil is M = |M 1，max -M 2，max |

[0022] Compared with the prior art, the technical scheme of the present application has the following beneficial effects:

[0023] 1. The method for determining the influence of cutter head collision on surrounding soil during shield docking of the present application can accurately calculate the analytical expression of the maximum range of the deflected cutter head and determine the influence range of the deflected cutter head on the soil.

[0024] 2. The method for determining the influence of cutter head collision on surrounding soil during shield docking of the present application can macroscopically calculate the influence of the entire deflected shield machine on the soil within the length range of the shield machine.

[0025] 3. The method for determining the influence of cutter head collision on surrounding soil during shield docking of the present application is simple and clear, and the calculation method is simple and easy to understand. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a schematic diagram for calculating the cross-sectional area of the maximum range of the influence of the cutter head on the soil.

[0027] Figure 2 is a schematic diagram for calculating the volume of the influence of the entire shield machine on the soil. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application; obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom end" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "provided with", "sleeved / connected", "connected" and the like should be understood broadly, for example, "connected" can be wall-mounted connection, can be detachable connection, or integral connection, can be mechanical connection, can be electrical connection, can be direct connection, can be indirect connection through intermediate medium, can be internal communication of two elements, and the specific meaning of the above terms in the present application can be understood according to the specific circumstances by those skilled in the art.

[0031] Reference Figure 1 And Figure 2 The embodiment provides a method for determining the influence of cutter head collision on soil body when two shield machines are docked in the ground in a shield civil engineering mode, and the method comprises the following steps:

[0032] (1) determining the rated torques M 1，max , M 2，max of the cutter heads of two shield machines, the diameters D1 and D2 of the cutter heads and the length L of the shield machine.

[0033] According to the selected model of the shield machine, the rated torques M 1，max , M 2，max of the cutter heads of two shield machines, the diameters D1 and D2 of the cutter heads and the length L of the shield machine are determined.

[0034] (2) determining the position A(x0, y0) of the collision point of the two cutter heads.

[0035] A rectangular coordinate system is established with the center of the tunnel cross section as the coordinate origin, the horizontal direction as the x-axis, the vertical direction as the y-axis and the length direction of the tunnel as the z-axis. The position A(x0, y0) of the collision point of the two cutter heads is determined according to the method of geophysical prospecting.

[0036] (3) determining the undrained shear strength c u of the soil body around the cutter head.

[0037] The undrained shear strength c u of the soil body is determined by triaxial compression test.

[0038] (4) determining the cutting torque M generated by the cutter head on the soil body.

[0039] (4-1) when one cutter head of a shield machine rotates and the other cutter head of the shield machine is stationary, the cutting torque M generated by the cutter head on the soil body is M=M 1，max .

[0040] (4-2) when one cutter head of a shield machine rotates and the other cutter head of the shield machine rotates in the same direction, the cutting torque M generated by the cutter head on the soil body is M=M 1，max +M 2，max .

[0041] (4-3) When one shield machine cutterhead rotates and the other cutterhead reverses, the cutting torque generated by the cutterheads on the soil is M = |M 1，max -M 2，max |.

[0042] (5) Determine the maximum range of the impact of the cutterhead deflection on the soil. (See Figure 4) Figure 1 )

[0043] (5-1) Determine the center position B(x1, y1) of the rotating cutterhead and the intersection C(x2, y2) of the two cutterhead peripheries.

[0044] Determine the torque M = T generated by the soil on the collision point when the cutterhead is just stopped, then

[0045]

[0046]

[0047]

[0048]

[0049] where

[0050] It should be noted that after the cutterhead collides, it rotates around the collision point A, and the maximum range of the impact of the cutterhead deflection on the soil is composed of curve CE and curve EF, curve CE is the part of the cutterhead directly contacting the soil, and curve EF is the maximum range of the cutterhead that has been cut before stopping. Together with the above (1)-(4) equations, B(x1, y1), C(x2, y2) can be solved, and the angle is in radians.

[0051] (5-2) Determine the maximum range boundary generated by the cutterhead on the soil, which is curve CE, EF.

[0052] Curve CE:

[0053]

[0054] Curve EF:

[0055]

[0056] where

[0057]

[0058] The maximum range boundary generated by the cutterhead on the soil is composed of curve CE and curve EF, curve CE is a circle with B(x1, y1) as the center, A(x0, y0) as the center, curve EF is a part of a circle with radius A(x0, y0) as the center, curve EF is a part of a circle with radius

[0059] (6) Determine the cross-sectional area of the range of the cutter head affecting the soil, that is, the area enclosed by curve CGF and curve CDEF

[0060]

[0061] It should be noted that the area enclosed by curve CGF and curve CDEF is calculated by the method of block integration, where point C is the intersection of the two cutter heads, point G is the intersection of the fixed cutter head 2 and the x-axis, point F is the starting point of the deflection, point D is the farthest point of the trajectory CDEF along the negative x-axis, and point E is the demarcation point of different expressions of the deflection trajectory of the deflection cutter head 1; the angle is in radians.

[0062] (7) Determine the volume of the entire shield machine affecting the surrounding soil.

[0063]

[0064] It should be noted that the cross-sectional area of the entire shield machine affecting the surrounding soil is assumed to be linearly variable, with the maximum cross-sectional area of the cutter head being S, and the shield tail being connected to the segment, which is considered fixed, so the cross-sectional area of the shield tail affected is 0. The above formula is obtained by integration.

[0065] Example

[0066] A certain project uses two shield machines to excavate in opposite directions, using the method of civil underground docking. Due to negligence, the cutter heads of the two shield machines collide, one of which has stopped, and the deformation of the overlying soil at this time needs to be calculated using the method of the present application. According to the selected shield machine model, the rated torque M 1，max of the cutter heads of the two shield machines is determined as M 2，max = 5538 kN·m, the cutter head diameter D1 = D2 = 6.48 m, and the shield machine length L = 13.05 m. The center of the tunnel cross section is taken as the coordinate origin, the horizontal direction is taken as the x-axis, and the vertical direction is taken as the y-axis to establish a rectangular coordinate system. According to the method of geophysical prospecting, the position of the collision point of the two cutter heads A(-1.92 m, 1.34 m) is determined. According to the triaxial compression test, the undrained shear strength of the soil around the cutter head is c u = 41.21 kPa. The cutting torque of the cutter head on the soil is M = 5538 kN·m. Substituting into the formula, the maximum range of the cutter head allowed to rotate is obtained at positions B(-2.16, -0.99) and C(-2.33, 2.25), and the analytical expression of the maximum range curve is:

[0067] (x + 2.16) 2 +(y + 0.99)2 = 10.50 (-5.40≤x≤-2.33, -4.21≤y≤2.25)

[0068] (x+1.92) 2 +(y-1.34) 2 = 31.15 (-2.49≤x≤2.66, -4.21≤y≤-1.85)

[0069] The cross-sectional area S of the range of the cutter head affecting the soil is 13.921 m 2 . The volume V of the range of the whole shield machine affecting the soil is 90.835 m 3 .

[0070] The above description is only the preferred embodiment of the present application, but the design concept of the present application is not limited to this. Any skilled person in the art can make non-essential changes to the present application within the scope of the present application, which is an infringement of the protection scope of the present application.

Claims

1. A method for determining the influence of cutter head collision on the soil body when a shield and a civil earth tunnel butt in the ground, characterized in that The method comprises the following steps: (1) determining the rated torque M of the two shield machine cutters 1，max , M 2，max , the diameters D1, D2 of the cutters and the length L of the shield machine; (2) determining the position A(x0, y0) of the collision point of the two cutters; (3) determining the undrained shear strength c of the soil mass around the cutterhead u ; (4) determining the cutting torque M generated by the cutter on the soil; (5) determining the maximum range of the influence of the deflection of the cutter on the soil; (5-1) determining the center position B(x1, y1) of the rotating cutter and the intersection C(x2, y2) of the peripheries of the two cutters; When the cutter just stops, the torque M generated by the soil on the collision point is T, then wherein (5-2) Determine the maximum range of the cutter head on the soil boundary, which is curve CE, EF; Curve CE is a part of a circle with B(x1, y1) as the center, Curve EF is a part of a circle with A(x0, y0) as the center, with a radius of length (6) determining the sectional area of the range of the influence of the cutter on the soil, i.e. the area enclosed by the curve CGF and the curve CDEF; The area enclosed by the curve CGF and the curve CDEF is calculated by the method of block integration, wherein the point C is the intersection of the two cutters, the point G(x6, y6) is the intersection of the fixed cutter and the x axis, the point F(x5, y5) is the starting point of the deflection, the point D(x3, y3) is the farthest point of the trajectory CDEF in the negative direction of the x axis, and the point E(x4, y4) is the demarcation point of different expressions of the deflection trajectory of the deflected cutter. (7) determining the volume of the influence of the whole shield machine on the surrounding soil:

2. The method of claim 1, wherein the method is characterized by: In step 1, the rated torque M of the cutterheads of the two tunnel boring machines is determined based on the selected tunnel boring machine model. 1，max M 2，max The diameters D1 and D2 of the cutterhead and the length L of the tunnel boring machine.

3. The method of claim 1, wherein the method further comprises: determining the influence of the collision of the cutterhead on the soil mass based on the determined position of the shield tunneling machine and the determined position of the earthwork machine. In step 2, the center of the tunnel cross section is taken as the coordinate origin, the horizontal direction is taken as the x axis, the vertical direction is taken as the y axis, and the length direction of the tunnel is taken as the z axis to establish a rectangular coordinate system; and the position A(x0, y0) of the collision point of the two cutters is determined according to the method of geophysical prospecting.

4. The method of claim 1, wherein the method further comprises: determining the influence of the collision of the cutterhead on the soil mass when the shield and the earthwork are connected in the ground. The undrained shear strength c of the soil body is determined in Step 3 using triaxial compression testing u .

5. The method of claim 1, wherein the method further comprises: determining the influence of the collision of the cutterhead on the soil mass when the shield and the earthwork are docked in the ground. In step 4, the following sub-steps are included: (4-1) When one shield machine cutterhead rotates and the other shield machine cutterhead is stationary, the cutting torque generated by the cutterhead on the soil body is M=M 1，max ; (4-2) When one shield machine cutterhead rotates and the other shield machine cutterhead rotates in the same direction, the cutting torque generated by the cutterheads on the soil body is M = M 1，max + M 2，max ; (4-3) When one shield machine cutterhead rotates and the other shield machine cutterhead reverses rotation, the cutting torque generated by the cutterheads on the soil body is M = |M 1，max -M 2，max |

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