A shield tunnel and ground deformation control method

Abstract

The present invention discloses a method for controlling the deformation of a shield tunnel and strata. Before the segments are assembled, an adjusting pad is installed on the outside of each segment. The adjusting pad is provided with a secondary adjusting pad that fits tightly with the outside of the segment and a tertiary adjusting pad that fits tightly with the secondary adjusting pad. A primary adjusting pad that fits tightly with the secondary adjusting pad is arranged inside the secondary adjusting pad. The deformation of the tunnel and strata is controlled by grouting the primary adjusting pad, the secondary adjusting pad and the tertiary adjusting pad: during shield tunneling, the primary adjusting pad is activated to fill the gap at the shield tail; after the shield tunneling, the secondary adjusting pad is activated to form a grouting protective layer; during the process of the tunnel being put into use, the tertiary adjusting pad is activated. The present invention can not only accurately control the deformation of the shield tunnel and strata during the shield construction process, but also accurately control the deformation of the shield tunnel and strata after the tunnel is put into use, thereby ensuring the safety of the tunnel and its surrounding buildings for a long time.

Description

Technical Field

[0001] The invention relates to the technical field of shield construction, and in particular to a shield tunnel and a stratum deformation control method. Background Art

[0002] With the acceleration of the construction of modern cities in my country, urban public transportation has been vigorously developed. In urban rail transit, shield tunneling has become the mainstream construction method. In shield tunneling construction, synchronous grouting is widely used to control soil deformation. However, due to the uneven diffusion of slurry and the uneven properties of soil layers, it is difficult to accurately control soil deformation with synchronous grouting.

[0003] For shield tunnels across rivers, across seas and in coastal areas, the strata have high water content, large groundwater flow and strong scouring force. While the structure is subjected to high-pressure water, it also needs to withstand the corrosion of corrosive groundwater or seawater due to the high permeability of the strata. The protective layer formed by traditional synchronous grouting is easily diluted and scour by groundwater under the conditions of high water content, making it difficult to form a high-quality impermeable layer, which in turn affects the performance of the tunnel structure.

[0004] The shell diameter of the shield machine is larger than the outer diameter of the segment, resulting in a gap at the shield tail, causing ground subsidence. The relevant specifications have increasingly higher requirements for soil settlement and deformation. Traditional synchronous grouting is difficult to accurately control surface settlement to meet the expected standards. The grouting volume and grouting pressure are more controlled based on previous engineering experience. Improper operation during construction often causes problems such as excessive surface settlement, floating of the segment, and slurry flowing into the shield tail.

[0005] After synchronous grouting, a permanent protective structure is formed on the outside of the segment. During the long-term use of the tunnel, the tunnel will inevitably deform due to various construction projects around the tunnel. In this case, usually only various passive or active measures are taken during construction to control the tunnel from excessive deformation. This control cannot be accurate to a certain ring of the tunnel segment, so undesirable phenomena such as segment misalignment and excessive ovality will still occur. Therefore, it is necessary to develop a shield tunnel and stratum deformation control method that can economically, quickly and accurately control stratum and tunnel deformation, which can be applied both during the shield process and after the tunnel is put into use. Summary of the invention

[0006] In order to solve the technical problems existing in the known technology, the present invention provides a method for controlling the deformation of a shield tunnel and strata, which can not only accurately control the deformation of the shield tunnel and strata during the shield construction process, but also accurately control the deformation of the shield tunnel and strata after the tunnel is put into use, thereby ensuring the safety of the tunnel and its surrounding buildings in the long term.

[0007] The technical solution adopted by the present invention to solve the technical problems existing in the known technology is: a shield tunnel and stratum deformation control method, before the pipe segments are assembled, an adjustment pad is equipped on the outside of each pipe segment, the adjustment pad is provided with a secondary adjustment pad that fits tightly with the outside of the pipe segment and a tertiary adjustment pad that fits tightly with the secondary adjustment pad, a primary adjustment pad that fits tightly with the secondary adjustment pad is arranged inside the secondary adjustment pad, the primary adjustment pad has the same volume as the shield tail gap, is made of water-impermeable and grout-impermeable material, and ruptures under a set grouting pressure, the secondary adjustment pad is made of water-permeable and grout-permeable material, the tertiary adjustment pad is made of water-impermeable and grout-impermeable material, a grouting interface I is provided on the primary adjustment pad, the grouting interface I passes through the side wall of the pipe segment and the secondary adjustment pad, and a grouting interface II is provided on the tertiary adjustment pad, the grouting interface II passes through Through the pipe segment, the first-level adjustment pad and the second-level adjustment pad, the deformation of the tunnel and the stratum is controlled by grouting into the first-level adjustment pad, the second-level adjustment pad and the third-level adjustment pad: during shield excavation, the first-level adjustment pad is activated to fill the shield tail gap; after shield excavation, when the first-level adjustment pad cannot meet the design requirements of the tunnel and stratum deformation, the second-level adjustment pad is activated, and the method is: grouting is again injected into the first-level adjustment pad, the slurry bursts the first-level adjustment pad and seeps out through the second-level adjustment pad to form a grouting protective layer around the tunnel pipe segment; during the use of the tunnel, when it is necessary to control the deformation of the tunnel and the stratum, the corresponding third-level adjustment pad is activated to perform fine control on the deformation position of the tunnel; the slurry used in the first-level adjustment pad, the second-level adjustment pad and the third-level adjustment pad has slow setting characteristics and good fluidity, and has the required strength after initial setting.

[0008] The first-stage adjustment pad, the second-stage adjustment pad and the third-stage adjustment pad are made of anti-corrosion materials.

[0009] The secondary adjustment pad is made of elastic material.

[0010] The three-stage adjustment pad is made of elastic material.

[0011] The advantages and positive effects of the present invention are:

[0012] 1) The present invention adopts graded adjustment pads, which can adjust the deformation of the tunnel and soil layer multiple times. The shape of the adjustment pads is relatively fixed and easy to control, which greatly improves the construction accuracy. After the first-level adjustment pad is activated, whether to activate the second or third-level adjustment pad can be considered according to the specific construction conditions, which greatly improves the flexibility.

[0013] 2) The first-level adjustment pad used in the present invention can accurately fill the shield tail gap generated by each ring of segments. If the construction accuracy is sufficient, the construction difficulty can be greatly reduced.

[0014] 3) The secondary regulating pad adopted in the present invention can form a grouting protective layer on the basis of the rupture of the primary regulating pad, and has strong integrity.

[0015] 4) The three-stage adjustment pad designed by the present invention can be used in the later use of the tunnel. It can accurately and actively adjust the tunnel deformation caused by the surrounding foundation pit construction or other underground projects, and because of the use of slow-setting slurry, the regulation has the characteristic of "reversibility".

[0016] 5) The adjustment pad used in the present invention has an anti-corrosion outer wall protection, and the slurry forms a whole inside the adjustment pad, which can protect the grouting body from being easily corroded by groundwater. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A longitudinal section schematic diagram of the application of the present invention;

[0018] Figure 2 A schematic diagram of a three-dimensional model used in the present invention;

[0019] Figure 3 for Figure 1 Cross-sectional view of

[0020] Figure 4 is a flow chart of the present invention;

[0021] Figure 5 is a schematic cross-sectional view of a single pipe segment 6-1 in an initial state of the present invention;

[0022] Figure 6 It is a schematic longitudinal section diagram of a single pipe segment 6-1 in the initial state of the present invention;

[0023] Figure 7 A cross-sectional schematic diagram of a single pipe segment 6-2 in which the first-stage regulation is started according to the present invention;

[0024] Figure 8 This is a schematic longitudinal section diagram of a single pipe segment 6-2 when the first-level regulation of the present invention is started;

[0025] Fig. 9 A cross-sectional schematic diagram of a single pipe segment 6-3 for starting secondary regulation of the present invention;

[0026] Fig.10 This is a schematic longitudinal section diagram of a single pipe segment 6-3 when the second-level regulation is started in the present invention;

[0027] Fig.11 A cross-sectional schematic diagram of a single pipe segment 6-4 with three-stage regulation activated according to the present invention;

[0028] Fig.12 This is a schematic longitudinal section diagram of a single pipe segment 6-4 when the third-level regulation is started according to the present invention.

[0029] In the figure: 1. First-level adjusting pad; 2. Second-level adjusting pad; 3. Third-level adjusting pad; 4. Grouting interface I; 5. Grouting interface II; 6-1, 6-2, 6-3, 6-4, respectively represent the segments in four states; 7. Grouting protective layer; 8. Segment deformation monitoring device; 9. Grouting pump; 10. Control system. DETAILED DESCRIPTION

[0030] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0031] See also Figures 1 to 12 A shield tunnel and stratum deformation control method. Before the segments are assembled, an adjustment pad is installed on the outside of each segment. The adjustment pad is provided with a secondary adjustment pad 2 which fits tightly with the outside of the segment and a tertiary adjustment pad 3 which fits tightly with the secondary adjustment pad. A primary adjustment pad 1 which fits with the secondary adjustment pad is arranged inside the secondary adjustment pad 2.

[0032] The first-level adjustment pad 1 has the same volume as the shield tail gap, is made of water-impermeable and grout-impermeable materials, and ruptures under the set grouting pressure.

[0033] The secondary adjustment pad 2 is made of water-permeable and slurry-permeable material.

[0034] The three-stage adjustment pad 3 is made of water-proof and slurry-proof material.

[0035] A grouting interface I4 is provided on the primary adjusting pad 1 , and the grouting interface I4 passes through the pipe segment and the side wall of the secondary adjusting pad 2 .

[0036] A grouting interface II5 is provided on the third-level adjusting pad 3 , and the grouting interface II5 passes through the pipe segment, the first-level adjusting pad 1 and the second-level adjusting pad 2 .

[0037] The deformation of the tunnel and the stratum is controlled by injecting grout into the first-level adjustment pad 1, the second-level adjustment pad 2 and the third-level adjustment pad 3:

[0038] During shield construction, segments are assembled while tunneling. Please refer to segment 6-1 in the attached figure, where the outer adjustment pad is in the initial state.

[0039] During shield excavation, the first-level adjustment pad 1 is activated to fill the gap at the shield tail. Please refer to the segment 6-2 in the attached figure. The first-level adjustment pad 1 is activated on the outer adjustment pad.

[0040] After shield tunneling, when the primary adjustment pad 1 cannot meet the design requirements of tunnel and stratum deformation, the secondary adjustment pad 2 is activated. Please refer to the pipe segment 6-3 in the attached figure. The secondary adjustment pad 2 is activated on the outer adjustment pad. The method of activating the secondary adjustment pad 2 is: grouting into the primary adjustment pad 1 again, the slurry bursts the primary adjustment pad 1 and seeps out through the secondary adjustment pad 2, forming a grouting protective layer 7 around the tunnel. The secondary adjustment pad 2 has no grouting port, and the slurry enters the secondary adjustment pad 2 after the primary adjustment pad 1 breaks.

[0041] During the operation of the tunnel, when the deformation of the tunnel and the ground needs to be controlled, the three-level adjustment pad 3 is activated. Please refer to the pipe segment 6-4 in the attached figure. The outer adjustment pad activates the three-level adjustment pad 3. The method of activating the three-level adjustment pad 3 is: grouting into the three-level adjustment pad 3 through the corresponding grouting interface II5 to perform fine control on the deformation position of the tunnel.

[0042] The slurry used in the first-stage adjustment pad 1, the second-stage adjustment pad 2 and the third-stage adjustment pad 3 has a slow-setting property and good fluidity, and has a strength that meets the requirements after initial setting.

[0043] In this embodiment, in order to improve the anti-corrosion performance of the control structure, the first-level adjustment pad 1, the second-level adjustment pad 2 and the third-level adjustment pad 3 are made of anti-corrosion materials. In order to enhance the integrity of the grouting protective layer 7, the second-level adjustment pad 2 is made of elastic material. In order to simplify the structural design, the third-level adjustment pad 3 is made of elastic material.

[0044] When the present invention is applied, the deformation of the tunnel segments and the strata is monitored by the segment deformation monitoring device 8, the adjusting pad is grouted by the grouting pump 9, the control system 10 receives the adjusting pad pressure monitoring data and the segment deformation monitoring data, and the tunnel deformation data is calculated. The construction personnel can adjust the required grouting pressure and grouting amount according to the information of the control system.

[0045] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments, which are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can make many forms without departing from the scope of protection of the present invention and the claims, all of which fall within the scope of protection of the present invention.

Claims

1. A shield tunnel and ground deformation control method, characterized in that: Before assembling the pipe segments, an adjustment pad is installed on the outside of each pipe segment. The adjustment pad is provided with a secondary adjustment pad that fits tightly with the outside of the pipe segment and a tertiary adjustment pad that fits tightly with the secondary adjustment pad. A primary adjustment pad that fits tightly with the secondary adjustment pad is arranged inside the secondary adjustment pad. The first-level adjustment pad has the same volume as the shield tail gap and is made of water-impermeable and grout-impermeable materials. It will rupture under the set grouting pressure. The secondary adjustment pad is made of water-permeable and slurry-permeable materials. The three-stage adjustment pad is made of water-proof and slurry-proof material. A grouting interface I is provided on the first-level adjusting pad, and the grouting interface I passes through the pipe segment and the side wall of the second-level adjusting pad. A grouting interface II is provided on the third-level adjusting pad, and the grouting interface II passes through the pipe segment, the first-level adjusting pad and the second-level adjusting pad; The deformation of the tunnel and the ground is controlled by injecting grout into the first-stage adjustment pad, the second-stage adjustment pad and the third-stage adjustment pad: When the shield is being driven, the first-level adjustment pad is activated to fill the gap at the shield tail; After shield tunneling, when the primary adjustment pad cannot meet the design requirements of tunnel and stratum deformation, the secondary adjustment pad is activated by injecting grout into the primary adjustment pad again, so that the grout bursts the primary adjustment pad and seeps out through the secondary adjustment pad to form a grouting protection layer around the tunnel segment; During the operation of the tunnel, when it is necessary to control the deformation of the tunnel and the ground, the corresponding three-level adjustment pad is activated to perform fine control on the deformation position of the tunnel; The slurry used in the first-stage adjusting pad, the second-stage adjusting pad and the third-stage adjusting pad has slow-setting properties and good fluidity, and has a strength that meets the requirements after initial setting.

2. The shield tunnel and stratum deformation control method according to claim 1, characterized in that: The first-stage adjustment pad, the second-stage adjustment pad and the third-stage adjustment pad are made of anti-corrosion materials.

3. The shield tunnel and stratum deformation control method according to claim 2, characterized in that: The secondary adjustment pad is made of elastic material.

4. The shield tunnel and stratum deformation control method according to claim 1, characterized in that: The three-stage adjustment pad is made of elastic material.

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