Reinforcing structure for shield tunnel and reinforcing method for shield tunnel

Abstract

The invention discloses a reinforcing structure and a reinforcing method for a shield tunnel, a first jet grouting pile group comprises a plurality of first jet grouting piles, part of structures of the first jet grouting piles are located above the shield tunnel, and the other part of structures of the first jet grouting piles are located on the side of the shield tunnel; the supporting pile set comprises first supporting piles and second supporting piles, the first supporting piles are located below the shield tunnel, the second supporting piles are located below the shield tunnel, and the second supporting piles are arranged on the two sides of the first supporting piles. Therefore, the partial structure of the first jet grouting pile is located above the shield tunnel, and the first supporting pile and the second supporting pile are both located below the shield tunnel, so that reinforcing combination of an upper soil body and a lower soil body of the shield tunnel can be achieved, soil body deformation in the shield tunnel construction process is effectively controlled, the stability of the excavation face of the shield tunnel is improved, and the construction efficiency of the shield tunnel is improved. After-construction settlement of the shield tunnel is reduced, the construction quality of the shield tunnel is improved, the long-term use performance of the shield tunnel is guaranteed, and the reinforcing structure is convenient to construct and low in construction difficulty.

Description

Technical Field

[0001] The invention relates to the field of civil engineering, and in particular to a reinforcement structure for a shield tunnel and a reinforcement method for a shield tunnel. Background Art

[0002] Deep, under-consolidated soft soil strata are widely distributed in coastal areas. With the rapid development of cities, more and more shield tunnel projects have to be constructed under this special geological condition. However, under-consolidated soft soil has low strength and large deformation, and often has poor stability problems before and after shield tunnel construction, such as instability of the excavation face, deformation of the stratum, and excessive post-construction settlement. These problems seriously affect construction safety and the service life of the tunnel.

[0003] In the related technology, in order to ensure the stability during construction and control the long-term settlement of soft soil layers, it is necessary to pre-reinforce the soft and weak strata within a certain range around the tunnel. However, the existing reinforcement scheme is unreasonable, resulting in poor stability of the excavation surface during excavation, a high risk of water and mud inrush, large post-construction settlement of the tunnel, and easy cracking and leakage of the tunnel segments, which in turn affects the construction quality and long-term performance of the shield tunnel in the under-consolidated soft soil layer. In addition, the existing reinforcement scheme has high requirements for construction conditions and is difficult to construct. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide a reinforcement structure for a shield tunnel, which can reinforce underconsolidated soft soil layers and effectively control soil deformation, thereby improving the construction quality of the shield tunnel and enhancing the long-term performance of the shield tunnel.

[0005] The present invention further proposes a method for reinforcing a shield tunnel.

[0006] The reinforcement structure for a shield tunnel according to the present invention comprises: a jet grouting pile group, the jet grouting pile group comprises at least one first jet grouting pile group, the first jet grouting pile group comprises a plurality of first jet grouting piles, the first jet grouting piles have an angle with a plumb line, a part of the structure of the first jet grouting piles is located above the shield tunnel and along the radial direction of the shield tunnel, another part of the structure of the first jet grouting piles is located on the side of the shield tunnel, and the first jet grouting piles are provided on both sides of the shield tunnel; a supporting pile group, the supporting pile group comprises a first supporting pile and a second supporting pile, the first supporting pile is parallel to the plumb line and located below the shield tunnel, the second supporting pile has an angle with the plumb line, the second supporting piles are located below the shield tunnel and along the radial direction of the shield tunnel, and the second supporting piles are provided on both sides of the first supporting piles.

[0007] According to the reinforcement structure for a shield tunnel of the present invention, by making part of the structure of the first rotary jet pile located above the shield tunnel, and making the first support pile and the second support pile located below the shield tunnel, the reinforcement of the upper soil and the lower soil of the shield tunnel can be combined, and the deformation of the soil during the construction of the shield tunnel can be effectively controlled, the stability of the excavation surface of the shield tunnel can be improved, and the post-construction settlement of the shield tunnel can be reduced, which is beneficial to improving the construction quality of the shield tunnel and ensuring the long-term performance of the shield tunnel. In addition, the reinforcement structure is easy to construct and has low construction difficulty.

[0008] In some examples of the present invention, the rotary jet pile group includes at least one second rotary jet pile group, the second rotary jet pile group includes multiple second rotary jet piles and multiple third rotary jet piles, the second rotary jet piles have an angle with the plumb line, part of the structure of the second rotary jet piles is located above the shield tunnel and along the radial direction of the shield tunnel, another part of the structure of the second rotary jet piles is located on the side of the shield tunnel, the third rotary jet piles are parallel to the plumb line and located above the shield tunnel, and the second rotary jet piles are provided on both sides of the shield tunnel.

[0009] In some examples of the present invention, the shield tunnel and the jet grouting pile group are both located in an underconsolidated soft soil layer, and the diameter of the shield tunnel is D;

[0010] The thickness of the under-consolidated soft soil layer above the bottom of the shield tunnel is Z1, and the angles between the first jet grouting pile, the second jet grouting pile and the plumb line are both α, satisfying the relationship: And / or, the thickness of the underconsolidated soft soil layer below the bottom of the shield tunnel is Z2, and the angle between the second support pile and the plumb line is β, satisfying the relationship:

[0011] In some examples of the present invention, there are multiple first jet grouting pile groups and multiple second jet grouting pile groups. Along the extension direction of the shield tunnel, multiple first jet grouting pile groups are arranged in sequence at intervals, and one second jet grouting pile group is arranged between every preset number of first jet grouting pile groups.

[0012] In some examples of the present invention, the diameters of the first rotary jet pile, the second rotary jet pile, and the third rotary jet pile are all A, the spacing distance between each adjacent two first rotary jet pile groups, the adjacent first rotary jet pile group and the second rotary jet pile group is L, and the diameter of the shield tunnel is D, satisfying the relationship: 1800mm≤L / A≤2400mm.

[0013] In some examples of the present invention, there are multiple supporting pile groups, and along the extension direction of the shield tunnel, the multiple supporting pile groups are arranged in sequence at intervals, the interval distance between each two adjacent supporting pile groups is 2L, and each of the supporting pile groups corresponds to the first rotary jet pile group or the second rotary jet pile group up and down.

[0014] In some examples of the present invention, the diameter of the shield tunnel is D, the top width of the first jet grouting pile group and the top width of the second jet grouting pile group are both D, and the bottom width of the first jet grouting pile group and the bottom width of the second jet grouting pile group are both 3D;

[0015] And / or, the diameters of the first rotary jet grouting pile, the second rotary jet grouting pile, and the third rotary jet grouting pile are all A, satisfying the relationship: 600mm≤A≤800mm;

[0016] And / or, the cement content of the first jet grouting pile is B, which satisfies the relationship: 15%≤B≤20%;

[0017] And / or, the cement content of the second jet grouting pile and the third jet grouting pile is C, satisfying the relationship: 20%≤C≤30%;

[0018] And / or, the spacing between the jet grouting piles in the first jet grouting pile group and the second jet grouting pile group is E, satisfying the relationship: 400mm≤E≤600mm, and the bite amount of the jet grouting piles in the first jet grouting pile group and the second jet grouting pile group is F, satisfying the relationship: 150mm≤F≤250mm.

[0019] In some examples of the present invention, the shield tunnel and the second support piles are both located in an underconsolidated soft soil layer, a portion of the structure of the first support piles is located in the underconsolidated soft soil layer, and another portion of the structure of the first support piles is located in a bottom bearing layer below the underconsolidated soft soil layer;

[0020] And / or, the diameter of the first support pile is G, which satisfies the relationship: 2000mm≤G≤2500mm;

[0021] And / or, the diameter of the second support pile is H, satisfying the relationship: 1000mm≤H≤1500mm.

[0022] A reinforcement method for a shield tunnel according to the present invention comprises: before excavation of the shield tunnel, driving a jet grouting pile group from the ground surface toward the excavation area of ​​the shield tunnel, the jet grouting pile group comprising at least one first jet grouting pile group, the first jet grouting pile group comprising a plurality of first jet grouting piles, the first jet grouting piles having an angle with a plumb line, a part of the structure of the first jet grouting pile being located above the excavation area and along the radial direction of the shield tunnel, another part of the structure of the first jet grouting pile being located on the side of the excavation area, and both sides of the excavation area having the first jet grouting piles;

[0023] After the shield tunnel is assembled, a support pile group is installed through the grouting holes reserved in the internal segments of the shield tunnel. The support pile group includes a first support pile and a second support pile. The first support pile is parallel to the plumb line and is located below the shield tunnel. The second support pile has an angle with the plumb line. The second support pile is located below the shield tunnel and along the radial direction of the shield tunnel. The second support piles are provided on both sides of the first support pile.

[0024] In some examples of the present invention, the rotary jet pile group includes at least one second rotary jet pile group, the second rotary jet pile group includes multiple second rotary jet piles and multiple third rotary jet piles, the second rotary jet piles have an angle with the plumb line, part of the structure of the second rotary jet piles is located above the excavation area and along the radial direction of the shield tunnel, another part of the structure of the second rotary jet piles is located on the side of the excavation area, the third rotary jet piles are parallel to the plumb line and cover the excavation area, and the second rotary jet piles are provided on both sides of the excavation area.

[0025] In some examples of the present invention, there are multiple first jet grouting pile groups and multiple second jet grouting pile groups. Along the extension direction of the shield tunnel, multiple first jet grouting pile groups are arranged in sequence at intervals, and one second jet grouting pile group is arranged between every preset number of first jet grouting pile groups.

[0026] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0028] Figure 1 is a cross-sectional view of a reinforcement structure according to an embodiment of the present invention (a first jet grouting pile group);

[0029] Figure 2 is a cross-sectional view of a reinforcement structure according to an embodiment of the present invention (a second jet grouting pile group);

[0030] Figure 3 is a cross-sectional view from another angle of the reinforcement structure according to an embodiment of the present invention;

[0031] Figure 4 Schematic diagram of a partial structure of a reinforcement structure according to an embodiment of the present invention.

[0032] Reference numerals:

[0033] Reinforced structure 100; shield tunnel 99;

[0034] Top fill layer 1; underconsolidated soft soil layer 2; bottom bearing layer 3;

[0035] Jet grouting pile group 10; first jet grouting pile group 11; second jet grouting pile group 12;

[0036] Support pile group 20; first support pile 21; second support pile 22; grouting hole 23; grouting pipe 24. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0038] Reference below Figure 1-Figure 4 A reinforcement structure 100 for a shield tunnel 99 according to an embodiment of the present invention is described.

[0039] like Figure 1-Figure 4 As shown, a reinforcement structure 100 for a shield tunnel 99 according to an embodiment of the present invention includes: a jet grouting pile group 10 and a supporting pile group 20 .

[0040] The jet grouting pile group 10 includes at least one first jet grouting pile group 11, the first jet grouting pile group 11 includes multiple first jet grouting piles, the first jet grouting piles have an angle with the plumb line, part of the structure of the first jet grouting piles is located above the shield tunnel 99 and along the radial direction of the shield tunnel 99, the other part of the structure of the first jet grouting piles is located on the side of the shield tunnel 99, and the shield tunnel 99 has first jet grouting piles on both sides; the support pile group 20 includes a first support pile 21 and a second support pile 22, the first support pile 21 is parallel to the plumb line and located below the shield tunnel 99, the second support pile 22 has an angle with the plumb line, the second support pile 22 is located below the shield tunnel 99, and along the radial direction of the shield tunnel 99, the second support pile 22 is provided on both sides of the first support pile 21.

[0041] As some embodiments of the present application, the jet grouting pile group 10 includes a first jet grouting pile group 11. As some embodiments of the present application, the jet grouting pile group 10 includes a plurality of first jet grouting pile groups 11. The first jet grouting pile group 11 includes first jet grouting piles, and the number of first jet grouting piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of first jet grouting piles is six, and the six first jet grouting piles all have an angle with the plumb line.

[0042] A portion of the first jet grouting pile is located above the shield tunnel 99, and along the radial direction of the shield tunnel 99 (i.e. Figure 1 In other words, part of the first rotary jet grouting piles can be arranged above and on the left side of the shield tunnel 99, and another part of the first rotary jet grouting piles can be arranged above and on the right side of the shield tunnel 99. A plurality of first rotary jet grouting piles can form a first rotary jet grouting pile group 11.

[0043] The first support pile 21 is parallel to the plumb line and is located below the shield tunnel 99, wherein the plumb line is parallel to the first direction (i.e. Figure 1 The first support pile 21 is parallel to the vertical line, that is, the extension direction of the first support pile 21 is parallel to the first direction (i.e. Figure 1 The first support pile 21 is parallel to the Z direction shown in the figure, and the first support pile 21 is located below the shield tunnel 99.

[0044] The second support pile 22 has an angle with the plumb line, that is, the second support pile 22 is at an angle to the first direction (i.e. Figure 1 The Z direction shown in the figure has an included angle, and the size of the included angle can be but is not limited to 45 degrees, 60 degrees, etc. As some embodiments of the present application, the size of the included angle between the second support pile 22 and the plumb line is 60 degrees, the second support pile 22 is located below the shield tunnel 99, and along the radial direction of the shield tunnel 99 (i.e. Figure 1 In the X direction shown in the figure), second supporting piles 22 are provided on both sides of the first supporting pile 21.

[0045] As some embodiments of the present application, before construction, it is necessary to design the pile diameter, reinforcement range, and length of the jet grouting pile group 10 and the support pile group 20 according to the design parameters of the shield tunnel 99. The design parameters of the shield tunnel 99 include but are not limited to the diameter of the shield tunnel 99, the burial depth, the geological conditions of the strata passed through, etc., and determine the angle between the first jet grouting pile, the second jet grouting pile, the second support pile 22 and the plumb line.

[0046] After the size is determined, the jet grouting pile group 10 is driven into the excavation area of ​​the shield tunnel 99 from the ground surface. If the jet grouting piles in the jet grouting pile group 10 have an angle with the plumb line, the jet grouting piles can be driven obliquely downward from the ground surface toward the excavation area of ​​the shield tunnel 99. In addition, during the construction process, the construction needs to be carried out according to the designed application depth and angle to ensure that the angle and depth meet the design requirements. After the construction is completed, soil can be filled above the jet grouting pile group 10 to form a top fill layer 1. By driving the jet grouting pile group 10 before the excavation of the shield tunnel 99, the stability of the excavation surface during the excavation process can be improved.

[0047] Next, the shield tunnel 99 is excavated and the segments are assembled, and grouting holes 23 are reserved for the support pile groups 20. After the shield tunnel 99 is assembled, the support pile groups 20 are installed through the grouting holes 23 reserved in the segments of the shield tunnel 99. That is to say, the support pile groups 20 can be driven downward into the under-consolidated soft soil layer 2 through the grouting holes 23 reserved in the segments of the assembled shield tunnel 99. As some embodiments of the present application, the second support piles 22 enter the halfway thickness of the under-consolidated soft soil layer 2 at the bottom of the shield tunnel 99.

[0048] As some embodiments of the present application, Figure 4 As shown, the grouting holes 23 reserved in the shield tunnel 99 segments can also be used as lifting holes to avoid secondary opening of the shield tunnel 99, which is beneficial to improving the structural strength of the shield tunnel 99.

[0049] As some embodiments of the present application, the grouting pipe 24 is connected to the grouting hole 23 to grout the first supporting pile 21 .

[0050] As some embodiments of the present application, the entire length of the shield tunnel 99 can be divided into a plurality of tunnel sections. For example, the entire length of the shield tunnel 99 can be divided into a first tunnel section, a second tunnel section, a third tunnel section, and a fourth tunnel section. The first tunnel section, the second tunnel section, the third tunnel section, and the fourth tunnel section have the same distance. During the construction of the shield tunnel 99, first, a jet grouting pile group 10 is applied to the underconsolidated soft soil layer 2 of the first tunnel section. Then, a jet grouting pile group 10 is applied to the underconsolidated soft soil layer 2 of the second tunnel section, and the excavation and assembly of the shield tunnel 99 of the first tunnel section are carried out at the same time. Then, a jet grouting pile group 10 is applied to the underconsolidated soft soil layer 2 of the third tunnel section, and the excavation and assembly of the shield tunnel 99 of the second tunnel section are carried out at the same time, and the support pile group 20 is applied to the first tunnel section at the same time. Then, the jet grouting pile group 10 is applied to the under-consolidated soft soil layer 2 of the fourth tunnel section, and the shield tunnel 99 of the third tunnel section is excavated and assembled at the same time, and the supporting pile group 20 is applied to the second tunnel section at the same time. Then, the shield tunnel 99 of the fourth tunnel section is excavated and assembled, and the supporting pile group 20 is applied to the third tunnel section at the same time. Finally, the supporting pile group 20 is applied to the fourth tunnel section. In this way, the construction efficiency of the shield tunnel 99 can be significantly improved and the construction period can be significantly shortened.

[0051] As some embodiments of the present application, the length of the first support pile 21 is greater than the length of the second support pile 22, and the support pile group 20 and the jet-jet pile group 10 can form an 'umbrella-shaped support system' to significantly improve the reinforcement effect.

[0052] As some embodiments of the present application, pressure sensors and hydraulic joints are required to be used during the construction of the supporting pile group 20. The pressure sensor can measure the internal pressure of the shield tunnel 99 from the grouting hole 23. When the pressure sensor measures that the pressure inside the grouting hole 23 is high, the opening size of the grouting hole 23 can be controlled by the hydraulic joint to adjust the mud discharge amount, thereby controlling the pressure value range in the soil body and reducing the secondary disturbance of grouting to the under-consolidated soft soil layer 2.

[0053] As some embodiments of the present application, the support pile group 20 can be constructed in the pipe segment of a shield tunnel 99 with a diameter of 3.5m or more. The pipe segment of the shield tunnel 99 adopts a unique porous tube, and a forced grouting device is provided at the front end of the pipe segment of the shield tunnel 99. The forced grouting device at the front end can regulate the underground pressure and reduce the risk of secondary disturbance of the under-consolidated soft soil layer 2 caused by grouting.

[0054] It should be noted that the jet grouting pile group 10 is constructed on the surface and should be completed before the excavation of the tunnel section of the corresponding shield tunnel 99 and the assembly of the pipe segments. The construction of the support pile group 20 is implemented when the working space is available after the excavation of the tunnel section of the corresponding shield tunnel 99 and the assembly of the pipe segments are completed. In combination with the above embodiments, it can be understood that after the completion of the jet grouting pile construction of the first tunnel section, the excavation and pipe segment assembly construction of the first tunnel section can be carried out, and the jet grouting pile construction of the second tunnel section can be carried out at the same time. After the excavation and pipe segment assembly construction of the shield tunnel 99 of the first tunnel section are completed, the support pile group 20 can be applied below the first tunnel section, and the excavation and pipe segment assembly construction of the second tunnel section and the jet grouting pile group 10 above the third tunnel section can be carried out at the same time. Such construction can significantly shorten the construction period and improve construction efficiency.

[0055] Furthermore, the reinforcement structure 100 of the present application can significantly improve the stability of the excavation surface of the shield tunnel 99, reduce the probability of water gushing and mud bursting in the shield tunnel 99, reduce the probability of cracking and leakage of the shield tunnel 99 segments, and can also reduce the construction conditions and construction difficulty, ensure the long-term performance of the shield tunnel 99, and effectively extend the service life of the shield tunnel 99.

[0056] Thus, by making part of the structure of the first jet grouting pile located above the shield tunnel 99 and the other part located on the side of the shield tunnel 99, and making the first support pile 21 and the second support pile 22 located below the shield tunnel 99, the upper and lower soil bodies of the shield tunnel 99 can be reinforced together, and the deformation of the soil body during the construction of the shield tunnel 99 can be effectively controlled, and the stability of the excavation surface of the shield tunnel 99 can be improved, and the post-construction settlement of the shield tunnel 99 can be reduced, which is conducive to improving the construction quality of the shield tunnel 99 and ensuring the long-term performance of the shield tunnel 99. In addition, the reinforcement structure 100 is easy to construct and has low construction difficulty.

[0057] By making the first jet grouting pile and the second jet grouting pile have an angle with the plumb line, the under-consolidated soft soil layer 2 above the bottom of the shield tunnel 99 can be reinforced, and the inclined first jet grouting pile and the second jet grouting pile can disperse the soil pressure, thereby effectively reducing the soil pressure on the top of the shield tunnel 99. By making the second support pile 22 have an angle with the plumb line, the under-consolidated soft soil layer 2 below the bottom of the shield tunnel 99 can be reinforced, the structural strength of the support pile group 20 can be improved, and the structural strength of the shield tunnel 99 can be further improved. In addition, the inclined second support pile 22 can disperse the soil pressure and reduce the post-construction settlement of the shield tunnel 99. This arrangement enables the first jet grouting pile group 11, the second jet grouting pile group 12 and the support pile group 20 to form an "umbrella-shaped support system", which can significantly improve the reinforcement effect and significantly improve the stability and safety of the shield tunnel 99.

[0058] In some embodiments of the present invention, Figure 2 As shown, the jet grouting pile group 10 includes at least one second jet grouting pile group 12, the second jet grouting pile group 12 includes a plurality of second jet grouting piles and a plurality of third jet grouting piles, the second jet grouting piles have an angle with the plumb line, and part of the second jet grouting pile structure is located above the shield tunnel 99 and along the radial direction of the shield tunnel 99 (i.e. Figure 1 The other part of the second jet grouting pile is located on the side of the shield tunnel 99, the third jet grouting pile is parallel to the plumb line and is located above the shield tunnel 99, and the shield tunnel 99 has second jet grouting piles on both sides.

[0059] As some embodiments of the present application, the rotary jet pile group 10 includes a second rotary jet pile group 12. As some embodiments of the present application, the rotary jet pile group 10 includes multiple second rotary jet pile groups 12. The second rotary jet pile group 12 includes a second rotary jet pile and a third rotary jet pile. The number of the second rotary jet piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the second rotary jet piles is six, and the second rotary jet pile has an angle with the plumb line.

[0060] The number of the third rotary jet piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the third rotary jet piles is six, and the third rotary jet piles are parallel to the plumb line.

[0061] A portion of the second jet grouting pile is located above the shield tunnel 99, and along the radial direction of the shield tunnel 99 (i.e. Figure 1 In other words, part of the second rotary jet grouting piles can be arranged above and on the left side of the shield tunnel 99, and another part of the second rotary jet grouting piles can be arranged above and on the right side of the shield tunnel 99, that is, both sides of the shield tunnel 99 have second rotary jet grouting piles.

[0062] As some embodiments of the present application, the second jet grouting pile group 12 can be used to reinforce the shield tunnel 99, for example, along the extension direction of the shield tunnel 99 (i.e. Figure 3 In the Y direction shown in the figure, a second jet grouting pile group 12 is provided for every five first jet grouting pile groups 11, or a second jet grouting pile group 12 is provided for every six first jet grouting pile groups 11.

[0063] As some embodiments of the present application, when the first rotary jet pile group 11 is constructed, space needs to be reserved for the shield tunnel 99, that is, the first rotary jet pile group will not cover the excavation area of ​​the shield tunnel 99, and when the second rotary jet pile group 12 is constructed, the excavation area of ​​the shield tunnel 99 can be covered.

[0064] Such an arrangement can make the jet grouting pile group 10 arranged reasonably, which is beneficial to improving the stability of the jet grouting pile group 10 reinforcement, can improve the stability of the excavation surface during the excavation process, reduce the post-construction settlement of the shield tunnel 99, and is beneficial to improving the construction quality of the shield tunnel 99.

[0065] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the shield tunnel 99 and the jet grouting pile group 10 are both located in the under-consolidated soft soil layer 2, and the diameter of the shield tunnel 99 is D; the thickness of the under-consolidated soft soil layer 2 above the bottom of the shield tunnel 99 is Z1, and the angles between the first jet grouting pile, the second jet grouting pile and the plumb line are both α, satisfying the relationship:

[0066]

[0067] Among them, the angle α between the first jet grouting pile, the second jet grouting pile and the plumb line satisfies the relationship: That is to say, the inverse tangent of the ratio of 1.5 times the diameter D of the shield tunnel 99 to the thickness Z1 of the underconsolidated soft soil layer 2 above the bottom of the shield tunnel 99 is the angle α between the first jet grouting pile, the second jet grouting pile and the plumb line.

[0068] As some embodiments of the present application, the diameter of the shield tunnel 99 is D, which is 6.2 m, and the thickness of the underconsolidated soft soil layer 2 above the bottom of the shield tunnel 99 is Z1, which is 15 m. According to the above data, the angle between the first jet grouting pile, the second jet grouting pile and the plumb line is determined to be 22.5°.

[0069] Such a setting can reinforce the under-consolidated soft soil layer 2 above the bottom of the shield tunnel 99, and can make the angles between the first rotary jet grouting pile, the second rotary jet grouting pile and the plumb line reasonable. The inclined first rotary jet grouting pile and the second rotary jet grouting pile can disperse the soil pressure, thereby effectively reducing the soil pressure on the top of the shield tunnel 99.

[0070] In some embodiments of the present invention, Figure 1 As shown, the thickness of the underconsolidated soft soil layer 2 below the bottom of the shield tunnel 99 is Z2, and the angle between the second support pile 22 and the plumb line is β, which satisfies the relationship:

[0071] The angle β between the second support pile 22 and the plumb line satisfies the relationship: That is to say, the inverse tangent of the ratio of the diameter D of the shield tunnel 99 to 0.5 times the sum of the diameter D of the shield tunnel 99 and the thickness Z2 of the underconsolidated soft soil layer 2 below the bottom of the shield tunnel 99 is the angle β between the second support pile 22 and the plumb line.

[0072] As some embodiments of the present application, the diameter D of the shield tunnel 99 is 6.2 m, the thickness Z2 of the underconsolidated soft soil layer 2 below the bottom of the shield tunnel 99 is 9 m, and the angle between the second support pile 22 and the plumb line is determined to be 39.2° based on the above data.

[0073] Such a setting can reinforce the under-consolidated soft soil layer 2 below the bottom of the shield tunnel 99, make the angle of the second support pile 22 reasonable, improve the structural strength of the support pile group 20, further improve the structural strength of the shield tunnel 99, and the inclined second support pile 22 can disperse the soil pressure and reduce the post-construction settlement of the shield tunnel 99.

[0074] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the first jet grouting pile group 11 and the second jet grouting pile group 12 are both multiple and are arranged along the extension direction of the shield tunnel 99 (i.e. Figure 3 The plurality of first jet grouting pile groups 11 are sequentially arranged at intervals, and a second jet grouting pile group 12 is disposed between each preset number of first jet grouting pile groups 11.

[0075] The number of the first jet grouting pile groups 11 may be but not limited to ten, twenty, thirty, etc., and the number of the second jet grouting pile groups 12 may be but not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the first jet grouting pile groups 11 is twenty, the number of the second jet grouting pile groups 12 is four, and ... Figure 3 The twenty first jet grouting pile groups 11 are arranged in sequence at intervals, and a second jet grouting pile group 12 is arranged between every five first jet grouting pile groups 11.

[0076] As some embodiments of the present application, along the extension direction of the shield tunnel 99 (i.e. Figure 3 A second jet grouting pile group 12 is arranged between every six first jet grouting pile groups 11.

[0077] By providing a plurality of first jet grouting pile groups 11 and a plurality of second jet grouting pile groups 12 and providing a second jet grouting pile group 12 between each preset number of first jet grouting pile groups 11, it is beneficial to improve the stability of the jet grouting pile group 10 reinforcement, can significantly enhance the reinforcement effect of the jet grouting pile group 10, and such an arrangement can reduce construction costs, which is beneficial to improving the construction quality of the shield tunnel 99.

[0078] In some embodiments of the present invention, Figure 1 and Figure 3As shown, the diameters of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile are all A, the spacing between each two adjacent first rotary jet pile groups 11 and the spacing between adjacent first rotary jet pile groups 11 and second rotary jet pile groups 12 is L, and the diameter of the shield tunnel 99 is D, satisfying the relationship: 1800mm≤L / A≤2400mm.

[0079] That is to say, the ratio of L to A can be any value between 1800mm and 2400mm. For example, the ratio of L to A can be but not limited to 1800mm, 2000mm, 2400mm, etc. As some embodiments of the present application, the ratio of L to A is 2400mm.

[0080] By setting the ratio of L to A to any value between 1800 mm and 2400 mm, the ratio of L to A can be made reasonable, and the reinforcement effect of the jet grouting pile group 10 can be improved.

[0081] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, there are multiple supporting pile groups 20, along the extension direction of the shield tunnel 99 (i.e. Figure 3 The Y direction shown in the figure), a plurality of support pile groups 20 are arranged in sequence, the interval distance between each two adjacent support pile groups 20 is 2L, and each support pile group 20 corresponds to the first rotary jet pile group 11 or the second rotary jet pile group 12 up and down.

[0082] The number of the supporting pile groups 20 may be, but is not limited to, four, five, six, etc. As some embodiments of the present application, along the extension direction of the shield tunnel 99 (i.e. Figure 3 In the Y direction shown in the figure), six supporting pile groups 20 are arranged in sequence at intervals.

[0083] The spacing distance between each two adjacent support pile groups 20 is 2L, that is, the spacing distance between each two adjacent support pile groups 20 is twice the spacing distance between each two adjacent first rotary jet pile groups 11 and between adjacent first rotary jet pile groups 11 and second rotary jet pile groups 12. In other words, a support pile group 20 is set at every interval of 2L.

[0084] Each supporting pile group 20 corresponds to the first rotary jet pile group 11 or the second rotary jet pile group 12 up and down, that is, the supporting pile group 20 can be set corresponding to the first rotary jet pile group 11, or the supporting pile group 20 can be set corresponding to the second rotary jet pile group 12. In short, the supporting pile group 20 is set corresponding to the rotary jet pile group 10 up and down.

[0085] Such an arrangement can make the arrangement of the support pile group 20 reasonable, and can reliably reinforce the under-consolidated soft soil layer 2 below the bottom of the shield tunnel 99. Moreover, the support pile group 2 and the corresponding rotary jet pile group 10 can form an arch structure-like shape, which is beneficial to improving the strength of the under-consolidated soft soil layer 2 where the shield tunnel 99 is located, and improving the construction quality of the shield tunnel 99.

[0086] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the diameter of the shield tunnel 99 is D, the top width of the first jet grouting pile group 11 and the top width of the second jet grouting pile group 12 are both D, and the bottom width of the first jet grouting pile group 11 and the bottom width of the second jet grouting pile group 12 are both 3D.

[0087] That is to say, the diameter of the shield tunnel 99, the top width of the first rotary jet pile group 11, and the top width of the second rotary jet pile group 12 are all D, and the bottom width of the first rotary jet pile group 11 and the bottom width of the second rotary jet pile group 12 are both 3D. The bottom width of the first rotary jet pile group 11 is three times the diameter of the shield tunnel 99, the bottom width of the first rotary jet pile group 11 is three times the top width of the first rotary jet pile group 11, the bottom width of the first rotary jet pile group 11 is three times the top width of the second rotary jet pile group 12, and the bottom width of the second rotary jet pile group 12 is three times the diameter of the shield tunnel 99, the bottom width of the second rotary jet pile group 12 is three times the top width of the first rotary jet pile group 11, and the bottom width of the second rotary jet pile group 12 is three times the top width of the second rotary jet pile group 12.

[0088] Such an arrangement can significantly improve the stability of the excavation surface during the excavation process, which is beneficial to improving the construction quality of the shield tunnel 99.

[0089] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the diameters of the first rotary jet grouting pile, the second rotary jet grouting pile, and the third rotary jet grouting pile are all A, satisfying the relationship: 600mm≤A≤800mm.

[0090] Among them, the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile satisfies the relationship 600mm≤A≤800mm, that is, the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile can be any value between 600mm and 800mm, the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile can be but not limited to 600mm, 700mm, 800mm, etc. As some embodiments of the present application, the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile are all 800mm.

[0091] By making the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile any value between 600mm and 800mm, the diameter A of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile can be reasonably designed, and the construction difficulty and the reinforcement load of the rotary jet pile group 10 can be taken into account, which is beneficial to improving construction efficiency while ensuring construction quality.

[0092] In some embodiments of the present invention, the cement content of the first jet grouting pile is B, which satisfies the relationship: 15%≤B≤20%.

[0093] Among them, the cement content B of the first rotary jet pile satisfies the relationship 15%≤B≤20%, that is, the cement content B of the first rotary jet pile can be any value between 15% and 20%. For example, the cement content B of the first rotary jet pile can be but not limited to 15%, 18%, 20%, etc. As some embodiments of the present application, the cement content B of the first rotary jet pile is 18%.

[0094] By making the cement content B of the first jet grouting pile any value between 15% and 20%, the cement content of the first jet grouting pile can be reasonable, the structural strength of the first jet grouting pile can be improved, and the reinforcement performance of the first jet grouting pile group 11 can be improved.

[0095] In some embodiments of the present invention, the cement content of the second jet grouting pile and the third jet grouting pile is C, satisfying the relationship: 20%≤C≤30%.

[0096] Among them, the cement content C of the second rotary jet pile and the third rotary jet pile satisfies the relationship 20%≤C≤30%, that is, the cement content C of the second rotary jet pile and the third rotary jet pile can be any value between 20% and 30%. For example, the cement content C of the second rotary jet pile and the third rotary jet pile can be but not limited to 20%, 25%, 30%, etc. As some embodiments of the present application, the cement content C of the second rotary jet pile and the third rotary jet pile is 25%.

[0097] By setting the cement content C of the second and third jet grouting piles to any value between 20% and 30%, the cement content of the second and third jet grouting piles can be made reasonable, which can improve the structural strength of the second and third jet grouting piles and is beneficial to improving the reinforcement performance of the second jet grouting pile group 12.

[0098] In some embodiments of the present invention, the spacing between the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 is E, satisfying the relationship: 400mm≤E≤600mm, and the bite amount of the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 is F, satisfying the relationship: 150mm≤F≤250mm.

[0099] Among them, the spacing between the jet grouting piles in the first jet grouting pile group 11 is E, and the spacing between the jet grouting piles in the second jet grouting pile group 12 is E, and E satisfies the relationship 400mm≤E≤600mm. That is to say, the spacing E between the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 can be any value between 400mm and 600mm. For example, the spacing E between the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 can be but not limited to 400mm, 500mm, 600mm, etc. As some embodiments of the present application, the spacing E between the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 is 600mm.

[0100] The engagement amount of the jet grouting piles in the first jet grouting pile group 11 is F, and the engagement amount of the jet grouting piles in the second jet grouting pile group 12 is F, and F satisfies the relationship 150mm≤F≤250mm. That is to say, the engagement amount F of the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 can be any value between 150mm and 250mm. For example, the engagement amount F of the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 can be but not limited to 150mm, 200mm, 250mm, etc. As some embodiments of the present application, the engagement amount F of the jet grouting piles in the first jet grouting pile group 11 and the second jet grouting pile group 12 is 200mm.

[0101] Such a setting can make the spacing between the jet grouting piles and the bite amount of the jet grouting pile group 10 reasonable, can significantly improve the structural strength and reinforcement performance of the jet grouting pile group 10, can effectively improve the stability of the excavation surface during excavation, and effectively reduce the post-construction settlement of the shield tunnel 99.

[0102] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the shield tunnel 99 and the second support piles 22 are both located in the underconsolidated soft soil layer 2, part of the structure of the first support piles 21 is located in the underconsolidated soft soil layer 2, and another part of the structure of the first support piles 21 is located in the bottom bearing layer 3 below the underconsolidated soft soil layer 2.

[0103] As some embodiments of the present application, the length of another part of the structure of the first supporting pile 21 entering the bottom bearing layer 3 may be, but is not limited to, 0.8 m, 1 m, etc.

[0104] Such an arrangement can make the design of the first support pile 21 reasonable. By inserting part of the structure of the first support pile 21 into the bottom bearing layer 3, the shield tunnel 99 can be effectively supported by the first support pile 21, thereby significantly reducing the post-construction settlement of the shield tunnel 99.

[0105] In some embodiments of the present invention, the diameter of the first support pile 21 is G, satisfying the relationship: 2000mm≤G≤2500mm.

[0106] Among them, the diameter G of the first support pile 21 satisfies the relationship 2000mm≤G≤2500mm, that is, the diameter G of the first support pile 21 can be any value between 2000mm and 2500mm. For example, the diameter G of the first support pile 21 can be but not limited to 2000mm, 2200mm, 2500mm, etc. As some embodiments of the present application, the diameter G of the first support pile 21 is 2200mm.

[0107] By setting the diameter G of the first support pile 21 to any value between 2000 mm and 2500 mm, the diameter of the first support pile 21 can be reasonably designed, and the structural strength of the first support pile 21 can be improved, so that the first support pile 21 can effectively support the shield tunnel 99 .

[0108] In some embodiments of the present invention, the diameter of the second support pile 22 is H, satisfying the relationship: 1000 mm ≤ H ≤ 1500 mm.

[0109] Among them, the diameter H of the second support pile 22 satisfies the relationship 1000mm≤H≤1500mm, that is, the diameter H of the second support pile 22 can be any value between 1000mm and 1500mm. For example, the diameter H of the second support pile 22 can be but not limited to 1000mm, 1200mm, 1500mm, etc. As some embodiments of the present application, the diameter H of the second support pile 22 is 1200mm.

[0110] By setting the diameter H of the second support pile 22 to any value between 1000 mm and 1500 mm, the diameter of the second support pile 22 can be reasonably designed, and the structural strength of the second support pile 22 can be improved, so as to improve the supporting performance of the support pile group 20 .

[0111] A reinforcement method for a shield tunnel according to the present invention comprises: before excavation of the shield tunnel, driving a jet grouting pile group from the ground surface toward the excavation area of ​​the shield tunnel, the jet grouting pile group comprising at least one first jet grouting pile group, the first jet grouting pile group comprising a plurality of first jet grouting piles, the first jet grouting piles having an angle with a plumb line, a part of the first jet grouting pile structure being located above the excavation area and along the radial direction of the shield tunnel, another part of the first jet grouting pile structure being located on the side of the excavation area, and both sides of the excavation area having first jet grouting piles;

[0112] After the shield tunnel is assembled, a support pile group is installed through the grouting holes reserved in the internal segments of the shield tunnel. The support pile group includes a first support pile and a second support pile. The first support pile is parallel to the plumb line and is located below the shield tunnel. The second support pile has an angle with the plumb line. The second support pile is located below the shield tunnel and along the radial direction of the shield tunnel. Second support piles are provided on both sides of the first support pile.

[0113] As some embodiments of the present application, the rotary jet pile group includes a first rotary jet pile group. As some embodiments of the present application, the rotary jet pile group includes multiple first rotary jet pile groups. The first rotary jet pile group includes first rotary jet piles. The number of first rotary jet piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of first rotary jet piles is six, and the six first rotary jet piles have an angle with the plumb line.

[0114] A portion of the first jet grouting pile is located above the shield tunnel, and along the radial direction of the shield tunnel (i.e. Figure 1 In other words, part of the first rotary jet grouting piles can be arranged above and on the left side of the shield tunnel, and another part of the first rotary jet grouting piles can also be arranged above and on the right side of the shield tunnel. A plurality of first rotary jet grouting piles can form a first rotary jet grouting pile group.

[0115] As some embodiments of the present application, before construction, it is necessary to design the pile diameter, reinforcement range, and length of the jet grouting pile group and the support pile group according to the design parameters of the shield tunnel. The design parameters of the shield tunnel include but are not limited to the diameter of the shield tunnel, the burial depth, the geological conditions of the strata passed through, etc., and determine the angles between the first jet grouting pile, the second jet grouting pile, the second support pile and the plumb line.

[0116] After the size is determined, the jet grouting pile group is driven from the ground toward the excavation area of ​​the shield tunnel. If the jet grouting piles in the jet grouting pile group have an angle with the plumb line, the jet grouting piles can be driven obliquely downward from the ground toward the excavation area of ​​the shield tunnel. In addition, during the construction process, construction needs to be carried out according to the designed application depth and angle to ensure that the angle and depth meet the design requirements. After the construction is completed, soil can be filled above the jet grouting pile group to form a top fill layer. By driving the jet grouting pile group before the shield tunnel is excavated, the stability of the excavation surface during the excavation process can be improved.

[0117] Next, the shield tunnel is excavated and the segments are assembled, and grouting holes are reserved for the supporting pile groups. After the shield tunnel is assembled, the supporting pile groups are installed through the grouting holes reserved in the shield tunnel segments. That is to say, the supporting pile groups can be driven downward into the under-consolidated soft soil layer through the grouting holes reserved in the segments of the assembled shield tunnel. As some embodiments of the present application, the second supporting piles enter the position at half the thickness of the under-consolidated soft soil layer at the bottom of the shield tunnel.

[0118] As some embodiments of the present application, the grouting holes reserved in the shield tunnel segments can also be used as lifting holes, avoiding secondary openings in the shield tunnel, which is beneficial to improving the structural strength of the shield tunnel.

[0119] As some embodiments of the present application, Figure 4 As shown, the grouting pipe is connected to the grouting hole to grout the first supporting pile.

[0120] The first support pile is parallel to the plumb line and is located below the shield tunnel, wherein the plumb line is parallel to the first direction (i.e. Figure 1 The first support pile is parallel to the plumb line, that is, the extension direction of the first support pile is parallel to the first direction (i.e. Figure 1 The Z direction shown in the figure) is parallel, and the first supporting pile is located below the shield tunnel.

[0121] The second support pile has an angle with the plumb line, that is, the second support pile is at an angle with the first direction (i.e. Figure 1 The Z direction shown in the figure has an included angle, and the size of the included angle can be but is not limited to 45 degrees, 60 degrees, etc. As some embodiments of the present application, the size of the included angle between the second support pile and the plumb line is 60 degrees, the second support pile is located below the shield tunnel, and along the radial direction of the shield tunnel (i.e. Figure 1 In the X direction shown in the figure), second supporting piles are arranged on both sides of the first supporting pile.

[0122] As some embodiments of the present application, the length of the first support pile is greater than the length of the second support pile, and the support pile group and the jet-jet pile group can form an 'umbrella-shaped support system' to significantly improve the reinforcement effect.

[0123] As some embodiments of the present application, pressure sensors and hydraulic joints are required during the construction of the supporting pile group. The pressure sensors can measure the internal pressure of the tunnel from the grouting holes. When the pressure sensor measures that the pressure inside the grouting holes is high, the opening size of the grouting holes can be controlled by the hydraulic joints to adjust the mud discharge amount, thereby controlling the pressure value range in the soil and reducing the secondary disturbance of grouting to the under-consolidated soft soil strata.

[0124] As some embodiments of the present application, the supporting pile group can be constructed in the segments of a shield tunnel with a diameter of 3.5m or more. The segments of the shield tunnel adopt unique porous tubes, and a forced grouting device is provided at the front end of the shield tunnel segment. The forced grouting device at the front end can regulate the underground pressure and reduce the risk of secondary disturbance of the bottom soft soil by grouting.

[0125] Therefore, by making part of the structure of the first jet grouting pile located above the shield tunnel, and the other part located on the side of the shield tunnel, and making the first support pile and the second support pile located below the shield tunnel, the reinforcement of the upper and lower soil bodies of the shield tunnel can be combined, and the deformation of the soil body during the construction of the shield tunnel can be effectively controlled, which can improve the stability of the excavation surface of the shield tunnel, reduce the post-construction settlement of the shield tunnel, and help improve the construction quality of the shield tunnel and ensure the long-term performance of the shield tunnel. In addition, the reinforcement structure is easy to construct and has low construction difficulty.

[0126] In some embodiments of the present invention, Figure 2 As shown, the rotary jet pile group includes at least one second rotary jet pile group, the second rotary jet pile group includes multiple second rotary jet piles and multiple third rotary jet piles, the second rotary jet piles have an angle with the plumb line, part of the structure of the second rotary jet piles is located above the excavation area and along the radial direction of the shield tunnel, another part of the structure of the second rotary jet piles is located on the side of the excavation area, the third rotary jet piles are parallel to the plumb line and cover the excavation area, and there are second rotary jet piles on both sides of the excavation area.

[0127] As some embodiments of the present application, the rotary jet pile group includes a second rotary jet pile group. As some embodiments of the present application, the rotary jet pile group includes multiple second rotary jet pile groups. The second rotary jet pile group includes a second rotary jet pile and a third rotary jet pile. The number of the second rotary jet piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the second rotary jet piles is six, and the second rotary jet pile has an angle with the plumb line.

[0128] The number of the third rotary jet piles can be but is not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the third rotary jet piles is six, and the third rotary jet piles are parallel to the plumb line.

[0129] A portion of the second jet grouting pile is located above the shield tunnel, and along the radial direction of the shield tunnel (i.e. Figure 1 In other words, part of the second rotary jet grouting piles can be arranged above and on the left side of the shield tunnel, and another part of the second rotary jet grouting piles can be arranged above and on the right side of the shield tunnel, that is, there are second rotary jet grouting piles on both sides of the shield tunnel.

[0130] As some embodiments of the present application, the second jet grouting pile group can be used for the reinforcement of the shield tunnel, for example, along the extension direction of the shield tunnel (i.e. Figure 3 In the Y direction shown in the figure, a second rotary jet grouting pile group is arranged every five first rotary jet grouting pile groups, or a second rotary jet grouting pile group is arranged every six first rotary jet grouting pile groups.

[0131] As some embodiments of the present application, when the first rotary jet pile group is constructed, space needs to be reserved for the shield tunnel, that is, the first rotary jet pile group will not cover the excavation area of ​​the shield tunnel. When the second rotary jet pile group is constructed, the excavation area of ​​the shield tunnel can be covered.

[0132] Such an arrangement can make the jet grouting pile group set up reasonably, which is beneficial to improving the stability of the jet grouting pile group reinforcement, can improve the stability of the excavation surface during the excavation process, reduce the post-construction settlement of the shield tunnel, and is beneficial to improving the construction quality of the shield tunnel.

[0133] In some embodiments of the present invention, Figure 1-Figure 3As shown, the first jet grouting pile group and the second jet grouting pile group are both multiple and are arranged along the extension direction of the shield tunnel (i.e. Figure 3 A plurality of first jet grouting pile groups are arranged in sequence in an interval, and a second jet grouting pile group is arranged between each preset number of first jet grouting pile groups.

[0134] The number of the first jet grouting pile group may be but not limited to ten, twenty, thirty, etc., and the number of the second jet grouting pile group may be but not limited to six, eight, ten, etc. As some embodiments of the present application, the number of the first jet grouting pile group is twenty, the number of the second jet grouting pile group is four, and the number of the first jet grouting pile group is 20, and the number of the second jet grouting pile group is four. Figure 3 Twenty first jet grouting pile groups are arranged in sequence, and a second jet grouting pile group is arranged every five first jet grouting pile groups.

[0135] Such an arrangement can make the first jet grouting pile group and the second jet grouting pile group arranged reasonably, which is beneficial to improving the reinforcement performance of the jet grouting pile group and can significantly enhance the reinforcement effect of the jet grouting pile group. Moreover, such an arrangement can reduce construction costs and is beneficial to improving the construction quality of the shield tunnel.

[0136] As some embodiments of the present application, the construction of rotary jet grouting pile groups, shield tunnel excavation, and support pile group construction are carried out simultaneously.

[0137] During the construction of the rotary jet grouting pile group, the excavation of the shield tunnel can be carried out simultaneously, and the assembled shield tunnel can be placed in the excavation area and the supporting pile group can be constructed at the same time.

[0138] As some embodiments of the present application, the full length of the shield tunnel can be divided into a plurality of tunnel sections. For example, the full length of the shield tunnel can be divided into a first tunnel section, a second tunnel section, a third tunnel section, and a fourth tunnel section. The first tunnel section, the second tunnel section, the third tunnel section, and the fourth tunnel section have the same distance. During the construction of the shield tunnel, first, a rotary jet pile group is applied to the under-consolidated soft soil layer of the first tunnel section. Then, a rotary jet pile group is applied to the under-consolidated soft soil layer of the second tunnel section, and the excavation and assembly of the shield tunnel of the first tunnel section are carried out at the same time. Then, a rotary jet pile group is applied to the under-consolidated soft soil layer of the third tunnel section, and the excavation and assembly of the shield tunnel of the second tunnel section are carried out at the same time, and a supporting pile group is applied to the first tunnel section at the same time. Then, a rotary jet pile group is applied to the under-consolidated soft soil layer of the fourth tunnel section, and the excavation and assembly of the shield tunnel of the third tunnel section are carried out at the same time, and a supporting pile group is applied to the second tunnel section at the same time. Then, the shield tunnel of the fourth tunnel section is excavated and assembled, and the supporting pile group is applied to the third tunnel section at the same time. Finally, the supporting pile group is applied to the fourth tunnel section.

[0139] Such an arrangement can make the construction steps of the shield tunnel reasonable, can significantly reduce the construction period of the shield tunnel, make rational use of the construction time, and is conducive to improving construction efficiency.

[0140] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0141] In the description of the present invention, "first feature" or "second feature" may include one or more of the features.

[0142] In the description of the present invention, "plurality" means two or more.

[0143] In the description of the present invention, a first feature being “on” or “under” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

[0144] In the description of the present invention, “on”, “over” and “above” a first feature from a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0145] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0146] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A reinforcement structure for a shield tunnel, characterized in that: include: A jet grouting pile group, the jet grouting pile group includes at least one first jet grouting pile group, the first jet grouting pile group includes a plurality of first jet grouting piles, the first jet grouting piles have an angle with a plumb line, a part of the structure of the first jet grouting piles is located above the shield tunnel and along the radial direction of the shield tunnel, another part of the structure of the first jet grouting piles is located on the side of the shield tunnel, and both sides of the shield tunnel have the first jet grouting piles; A supporting pile group, the supporting pile group includes a first supporting pile and a second supporting pile, the first supporting pile is parallel to the plumb line and is located below the shield tunnel, the second supporting pile has an angle with the plumb line, the second supporting pile is located below the shield tunnel and along the radial direction of the shield tunnel, and the second supporting piles are arranged on both sides of the first supporting pile.

2. The reinforcement structure for a shield tunnel according to claim 1, characterized in that: The rotary jet pile group includes at least one second rotary jet pile group, the second rotary jet pile group includes multiple second rotary jet piles and multiple third rotary jet piles, the second rotary jet piles have an angle with the plumb line, part of the structure of the second rotary jet piles is located above the shield tunnel and along the radial direction of the shield tunnel, another part of the structure of the second rotary jet piles is located on the side of the shield tunnel, the third rotary jet piles are parallel to the plumb line and located above the shield tunnel, and the second rotary jet piles are provided on both sides of the shield tunnel.

3. The reinforcement structure for a shield tunnel according to claim 2, characterized in that: The shield tunnel and the jet-jet pile group are located in an under-consolidated soft soil layer, and the diameter of the shield tunnel is D; The thickness of the under-consolidated soft soil layer above the bottom of the shield tunnel is Z1, and the angles between the first jet grouting pile, the second jet grouting pile and the plumb line are both α, satisfying the relationship: And / or, the thickness of the underconsolidated soft soil layer below the bottom of the shield tunnel is Z2, and the angle between the second support pile and the plumb line is β, satisfying the relationship:

4. The reinforcement structure for a shield tunnel according to claim 2, characterized in that: There are multiple first jet grouting pile groups and multiple second jet grouting pile groups. Along the extension direction of the shield tunnel, multiple first jet grouting pile groups are arranged in sequence at intervals, and one second jet grouting pile group is arranged between every preset number of first jet grouting pile groups.

5. The reinforcement structure for a shield tunnel according to claim 4, characterized in that: The diameters of the first rotary jet pile, the second rotary jet pile and the third rotary jet pile are all A, the spacing between each adjacent two first rotary jet pile groups and the spacing between the adjacent first rotary jet pile groups and the second rotary jet pile groups is L, and the diameter of the shield tunnel is D, satisfying the relationship: 1800mm≤L / A≤2400mm.

6. The reinforcement structure for a shield tunnel according to claim 5, characterized in that: There are multiple support pile groups, which are arranged in sequence along the extension direction of the shield tunnel. The interval between each two adjacent support pile groups is 2L, and each support pile group corresponds to the first rotary jet pile group or the second rotary jet pile group up and down.

7. The reinforcement structure for a shield tunnel according to claim 2, characterized in that: The diameter of the shield tunnel is D, the top width of the first jet grouting pile group and the top width of the second jet grouting pile group are both D, and the bottom width of the first jet grouting pile group and the bottom width of the second jet grouting pile group are both 3D; And / or, the diameters of the first rotary jet grouting pile, the second rotary jet grouting pile, and the third rotary jet grouting pile are all A, satisfying the relationship: 600mm≤A≤800mm; And / or, the cement content of the first jet grouting pile is B, which satisfies the relationship: 15%≤B≤20%; And / or, the cement content of the second jet grouting pile and the third jet grouting pile is C, satisfying the relationship: 20%≤C≤30%; And / or, the spacing between the jet grouting piles in the first jet grouting pile group and the second jet grouting pile group is E, satisfying the relationship: 400mm≤E≤600mm, and the bite amount of the jet grouting piles in the first jet grouting pile group and the second jet grouting pile group is F, satisfying the relationship: 150mm≤F≤250mm.

8. The reinforcement structure for a shield tunnel according to any one of claims 1 to 7, characterized in that: The shield tunnel and the second support piles are both located in an underconsolidated soft soil layer, a portion of the structure of the first support piles is located in the underconsolidated soft soil layer, and another portion of the structure of the first support piles is located in a bottom bearing layer below the underconsolidated soft soil layer; And / or, the diameter of the first support pile is G, which satisfies the relationship: 2000mm≤G≤2500mm; And / or, the diameter of the second support pile is H, satisfying the relationship: 1000mm≤H≤1500mm.

9. A method for reinforcing a shield tunnel, characterized in that: include: Before the shield tunnel is excavated, a jet grouting pile group is driven from the ground surface toward the excavation area of ​​the shield tunnel, the jet grouting pile group includes at least one first jet grouting pile group, the first jet grouting pile group includes a plurality of first jet grouting piles, the first jet grouting piles have an angle with a plumb line, a part of the structure of the first jet grouting pile is located above the excavation area and along the radial direction of the shield tunnel, another part of the structure of the first jet grouting pile is located on the side of the excavation area, and both sides of the excavation area have the first jet grouting piles; After the shield tunnel is assembled, a support pile group is installed through the grouting holes reserved in the internal segments of the shield tunnel. The support pile group includes a first support pile and a second support pile. The first support pile is parallel to the plumb line and is located below the shield tunnel. The second support pile has an angle with the plumb line. The second support pile is located below the shield tunnel and along the radial direction of the shield tunnel. The second support piles are provided on both sides of the first support pile.

10. The method for reinforcing a shield tunnel according to claim 9, characterized in that: The rotary jet pile group includes at least one second rotary jet pile group, the second rotary jet pile group includes multiple second rotary jet piles and multiple third rotary jet piles, the second rotary jet piles have an angle with the plumb line, part of the structure of the second rotary jet piles is located above the excavation area and along the radial direction of the shield tunnel, another part of the structure of the second rotary jet piles is located on the side of the excavation area, the third rotary jet piles are parallel to the plumb line and cover the excavation area, and the second rotary jet piles are provided on both sides of the excavation area.

11. The method for reinforcing a shield tunnel according to claim 10, characterized in that: There are multiple first jet grouting pile groups and multiple second jet grouting pile groups. Along the extension direction of the shield tunnel, multiple first jet grouting pile groups are arranged in sequence at intervals, and one second jet grouting pile group is arranged between every preset number of first jet grouting pile groups.

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