Stacked tunnel deformation settlement control method and system

Abstract

The invention relates to the technical field of tunnel settlement, in particular to a stacked tunnel deformation settlement control method and system.The stacked tunnel deformation settlement control method comprises the steps that construction preparation and deployment are conducted before stacked tunnel construction, and monitoring points are arranged on an upper soil body in a shield tunnel; a special pipe piece is used for tunnel construction, grouting hole positions and pre-embedded grouting pipes are arranged on the special pipe piece in the transverse direction and the longitudinal direction, the grouting pipes are distributed towards the periphery in an X shape, and two grout outlet hole positions are formed in each forked position; the deformation and settlement conditions in the stacked tunnel construction process are monitored in real time, and monitoring data are obtained; and in the shield construction process, construction parameters are adjusted in real time according to monitoring data, and grouting reinforcement is conducted. Omnibearing uniform grouting is achieved through an X-shaped grouting system of a special pipe piece, a real-time monitoring and dynamic adjusting mechanism is combined, stratum settlement and tunnel deformation are remarkably reduced, and the maximum settlement of the earth surface is reduced by 45% or above. According to the method, only the duct pieces need to be slightly transformed, the cost increase is small, and an efficient and reliable control scheme is provided for stacked tunnel construction.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel settlement, and in particular to a method and system for controlling deformation and settlement of a stacked tunnel. Background Art

[0002] In recent years, due to factors such as station setting, environmental assessment and space utilization restrictions, the spatial layout of shield sections in some urban subway lines sometimes adopts the method of stacking two tunnels. Compared with parallel tunnels, the construction of stacked tunnels has a more complex impact on the existing tunnel structure and stratum deformation. The construction of stacked tunnels will cause multiple construction disturbances to the stratum, resulting in aggravated deformation of the stratum and surrounding structures, and the later built tunnel will cause large displacement and adverse force on the existing tunnel structure.

[0003] Therefore, the key to the construction of stacked shield tunnels is to control the mutual influence of tunnel construction and the impact on surrounding buildings (structures) within the required limits. Since the construction of stacked tunnels has a significant impact on the surrounding strata, it is particularly necessary to study the deformation of the surrounding soil and tunnel settlement caused by the crossing of the stacked shield and to formulate reasonable and effective reinforcement control measures. Although the number of stacked tunnel engineering projects has gradually increased in recent years, there are relatively few related research results, and the research on the mutual influence of stacked shield tunnel construction and its impact on the surrounding environment is still insufficient. There is also a relative lack of relevant experience in reinforcement control measures, making it difficult to balance safety and economy. Either the construction quality and safety are not guaranteed, or economic losses are caused due to excessive conservatism. The present invention proposes a method for controlling deformation and settlement of stacked tunnels, which can effectively control the deformation, settlement and adverse stress conditions of stacked tunnel sections at a relatively low cost. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to solve the adverse effects of large displacement and stress on the existing tunnel structure caused by the construction of the stacked tunnel. On the basis of the existing shield segments, a new segment is used to replace the existing shield segments. In the overlapping section of the tunnel, a special segment with newly added grouting holes in the horizontal and vertical directions is used. When the segments are prefabricated, grouting pipes are installed inside the segments. Finally, during the construction of the stacked tunnel, the newly added grouting holes in the segments are used to reinforce the overlapping parts with grouting, so as to achieve the purpose of controlling the displacement and adverse stress of the existing tunnel. How to solve the problem of effectively controlling the settlement and adverse stress of the completed tunnel.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a method for controlling deformation and settlement of a stacked tunnel, which includes, before the stacked tunnel is constructed, performing construction preparation and deployment, and arranging monitoring points in the upper soil in the shield tunnel;

[0008] Tunnel construction is carried out using special segments, wherein the special segments are provided with grouting holes and pre-buried grouting pipes in the transverse and longitudinal directions;

[0009] Real-time monitoring of deformation and settlement during the construction of the stacked tunnel to obtain monitoring data;

[0010] During the shield construction process, construction parameters are adjusted in real time according to monitoring data and grouting reinforcement is carried out.

[0011] As a preferred solution of the deformation and settlement control method of the stacked tunnel described in the present invention, the grouting pipes of the special pipe segment are made of polymer materials and are distributed in an X-shape inside the pipe segment.

[0012] Two additional slurry outlet holes are set at each bifurcation, totaling 8 slurry outlet holes;

[0013] The slurry outlet hole is a circular tube with a diameter of 10 cm, which is used to reinforce the lateral and radial soil of the pipe segment.

[0014] As a preferred solution of the deformation and settlement control method of the stacked tunnel described in the present invention, the installation of the grouting pipe includes: when manufacturing the pipe segment in the pipe segment factory, firstly putting the grouting pipe into the mold, fixing it and plugging the grouting hole and the grouting outlet;

[0015] Tie up the steel bars and pour concrete in the mold for curing; after curing is completed, remove the plugs from the grouting holes and outlets.

[0016] As a preferred solution of the deformation and settlement control method of a stacked tunnel described in the present invention, the tunnel soil pressure control value is 1.2 bar; the tunneling speed of the shield machine is controlled at 20 mm / min; the cutter head speed is controlled at 0.8 r / min; the cutter head torque is controlled at 3000 KN〃m; and the cutter head thrust is controlled at 800t to 1500t.

[0017] As a preferred solution of the deformation and settlement control method of a stacked tunnel described in the present invention, the grouting reinforcement includes synchronous grouting and secondary grouting;

[0018] The synchronous grouting adopts cement mortar, the grouting pressure is 0.5~1.0MPa, and the grouting volume per ring is ≥6m 3 Secondary grouting The sleeve valve pipe with t=3mm and length of 2m is injected with cement-water-glass double liquid slurry through the pre-buried grouting hole, and the grouting pressure is 0.5-1.0MPa;

[0019] After grouting is completed, the unconfined compressive strength of the reinforced body shall not be less than 0.8MPa.

[0020] As a preferred solution of the deformation and settlement control method of the stacked tunnel described in the present invention, the grouting reinforcement range is the soil within the 3-5m line outside the segment within the 180° range of the tunnel arch;

[0021] When the overlapping distance of two tunnels is less than the tunnel diameter, the surrounding strata should be reinforced to a range of 6 times the tunnel diameter;

[0022] The radial grouting reinforcement length is 3D to 6D, where D is the tunnel diameter; when the distance between the new and old tunnels is less than the tunnel diameter, the reinforcement length is 6D.

[0023] As a preferred solution of the deformation and settlement control method of the stacked tunnels described in the present invention, the construction is carried out according to the following steps: firstly, the down tunnel is constructed, and then the upper tunnel is constructed, so as to ensure that the tunnel constructed first is not disturbed by the later tunnel and thus does not undergo settlement and deformation;

[0024] Dynamically adjust construction parameters based on monitoring data. When large deformation is detected, reduce the shield machine's propulsion speed and cutterhead speed.

[0025] During the tunneling process of the shield machine, the operating parameters of the shield machine are calculated and adjusted according to the cover depth.

[0026] In a second aspect, an embodiment of the present invention provides a deformation and settlement control system for a stacked tunnel, which comprises

[0027] Deployment module: Before the construction of the stacked tunnel, construction preparation and deployment are carried out, and monitoring points are set up in the upper soil of the shield tunnel;

[0028] Construction module, using special segments for tunnel construction, the special segments are provided with grouting holes and pre-buried grouting pipes in the horizontal and vertical directions;

[0029] Monitoring module, real-time monitoring of deformation and settlement during the construction of the stacked tunnel, and acquisition of monitoring data;

[0030] The grouting module adjusts the construction parameters in real time according to the monitoring data and performs grouting reinforcement during the shield construction process.

[0031] In a third aspect, an embodiment of the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of a method for controlling deformation and settlement of a stacked tunnel as described in the first aspect of the present invention are implemented.

[0032] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of a method for controlling deformation and settlement of a stacked tunnel as described in the first aspect of the present invention are implemented.

[0033] The beneficial effects of the present invention are as follows: the deformation and settlement control method and system of the stacked tunnel provided by the present invention can effectively control the displacement and adverse stress of the existing tunnel; in view of the deformation and settlement problems that are easy to occur during the construction of the stacked tunnel, sensors are added to monitor the deformation and settlement of the tunnel in real time, so as to adjust the grouting amount synchronously according to the deformation and settlement conditions; in view of the adverse effects of the large displacement and stress caused by the construction of the stacked tunnel on the existing tunnel structure, on the basis of the existing shield segments, special segments with newly added grouting holes in the horizontal and vertical directions are used in the overlapping sections of the tunnel, and grouting pipes are installed inside the segments when prefabricating the segments, and slurry is discharged through multiple holes; compared with the prior art, the deformation and settlement control method of the stacked tunnel proposed by the present invention uses a relatively low cost to effectively control the settlement and adverse stress of the completed tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 It is a flow chart of a method and system for controlling deformation and settlement of a stacked tunnel;

[0036] Figure 2 A computer equipment diagram of a stacked tunnel deformation and settlement control method and system;

[0037] Figure 3 It is an overall schematic diagram of a common shield segment of a stacked tunnel deformation and settlement control method and system;

[0038] Figure 4 It is an overall schematic diagram of a new type of special segment used in the present invention of a stacked tunnel deformation and settlement control method and system;

[0039] Figure 5 A cross-sectional structural diagram of a special segment for a stacked tunnel deformation and settlement control method and system;

[0040] Figure 6 A top view of the structure of a special segment of a stacked tunnel deformation and settlement control method and system;

[0041] Figure 7A schematic diagram of the scope of soil layer reinforcement through grouting of special pipe segments in a stacked tunnel deformation settlement control method and system;

[0042] Figure 8 A new tunnel of a stacked tunnel deformation and settlement control method and system is located below an existing tunnel, and a schematic diagram of the reinforcement range;

[0043] Fig. 9 A new tunnel of a stacked tunnel deformation and settlement control method and system is located below the existing tunnel, and a schematic diagram of the reinforcement range;

[0044] Fig.10 A new tunnel of a stacked tunnel deformation and settlement control method and system is located above an existing tunnel, and a schematic diagram of the reinforcement range;

[0045] Fig.11 A new tunnel of a stacked tunnel deformation and settlement control method and system is located above the existing tunnel, and a schematic diagram of the reinforcement range;

[0046] Fig.12 A schematic diagram of the simulation of ground settlement produced by using a stacked tunnel deformation settlement control method and system using the scheme;

[0047] Fig.13 The schematic diagram of settlement simulation of a deformation and settlement control method and system for a stacked tunnel and a common construction method that does not adopt this scheme is shown. DETAILED DESCRIPTION

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0050] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0051] Example 1

[0052] Reference Figure 1-2 , which is the first embodiment of the present invention, provides a method for controlling deformation and settlement of a stacked tunnel, comprising:

[0053] S100: Before the construction of the stacked tunnel, construction preparation and deployment are carried out, and monitoring points are set up in the upper soil of the shield tunnel;

[0054] S200: Use special segments for tunnel construction, with grouting holes and pre-buried grouting pipes in the horizontal and vertical directions;

[0055] S201: The grouting pipes of the special pipe segments are made of polymer materials and are distributed in an X shape inside the pipe segments.

[0056] Two additional slurry outlet holes are set at each bifurcation, totaling 8 slurry outlet holes;

[0057] The slurry outlet hole is a circular tube with a diameter of 10 cm, which is used to reinforce the lateral and radial soil of the pipe segment.

[0058] S202: When manufacturing the pipe segment in the pipe segment factory, firstly put the grouting pipe into the mold, fix it, and plug the grouting hole and the grouting outlet;

[0059] Tie up the steel bars and pour concrete in the mold for curing; after curing is completed, remove the plugs from the grouting holes and outlets.

[0060] S300: Real-time monitoring of deformation and settlement during the construction of the stacked tunnel to obtain monitoring data;

[0061] S400: During the shield construction process, the construction parameters are adjusted in real time according to the monitoring data and grouting reinforcement is carried out.

[0062] S401: Shield construction parameters include: tunnel soil pressure control value is 1.2bar; shield machine excavation speed is controlled at 20mm / min; cutter head speed is controlled at 0.8r / min; cutter head torque is controlled at 3000KN〃m; cutter head thrust is controlled at 800t~1500t.

[0063] S402: The above-mentioned grouting reinforcement includes synchronous grouting and secondary grouting;

[0064] The synchronous grouting adopts cement mortar, the grouting pressure is 0.5-1.0MPa, and the grouting volume per ring is ≥6m 3 Secondary grouting The sleeve valve pipe with t=3mm and length of 2m is injected with cement-water-glass double grout through the pre-buried grouting hole, and the grouting pressure is 0.51.0MPa;

[0065] After grouting is completed, the unconfined compressive strength of the reinforced body shall not be less than 0.8MPa.

[0066] S403: The grouting reinforcement range is the soil within the 3-5m line outside the segment within 180° of the tunnel arch;

[0067] When the overlapping distance of two tunnels is less than the tunnel diameter, the surrounding strata should be reinforced to a range of 6 times the tunnel diameter;

[0068] The radial grouting reinforcement length is 3D to 6D, where D is the tunnel diameter; when the distance between the new and old tunnels is less than the tunnel diameter, the reinforcement length is 6D.

[0069] The construction is carried out in the following steps: first carry out the down tunnel construction, then the upper tunnel construction, to ensure that the tunnel constructed first is not disturbed by the later tunnel construction and does not undergo settlement and deformation;

[0070] Dynamically adjust construction parameters based on monitoring data. When large deformation is detected, reduce the shield machine's propulsion speed and cutterhead speed.

[0071] During the tunneling process of the shield machine, the operating parameters of the shield machine are calculated and adjusted according to the cover depth.

[0072] Furthermore, this embodiment also provides a stacked tunnel deformation and settlement control system, including:

[0073] Deployment module: Before the construction of the stacked tunnel, construction preparation and deployment are carried out, and monitoring points are set up in the upper soil of the shield tunnel;

[0074] Construction module, using special segments for tunnel construction, with grouting holes and pre-buried grouting pipes in the horizontal and vertical directions;

[0075] Monitoring module, real-time monitoring of deformation and settlement during the construction of the stacked tunnel, and acquisition of monitoring data;

[0076] The grouting module adjusts the construction parameters in real time according to the monitoring data and performs grouting reinforcement during the shield construction process.

[0077] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, a method for controlling deformation and settlement of a stacked tunnel as proposed in the above embodiment is implemented.

[0078] In summary, the X-shaped distributed grouting pipe structure achieves 360-degree all-round grouting coverage, overcoming the problem of uneven coverage of traditional single-point grouting; the multi-point grouting design makes the grouting more uniform and improves the reinforcement effect; the embedded design avoids the damage to the pipe segment structure caused by on-site drilling and improves the overall strength of the pipe segment; by arranging multiple monitoring points, real-time dynamic monitoring of the entire section is achieved, improving the monitoring accuracy; through real-time data analysis and curve fitting, abnormal deformation can be discovered in time; construction parameters are adjusted based on monitoring data to achieve precise construction control; through a reasonable construction sequence arrangement, the upper tunnel is avoided from being affected by the lower construction and causing additional deformation; the ground settlement is reduced by about 45%, significantly improving the construction quality; and the The impact on surrounding buildings was reduced; the reinforcement effect was improved through the double grouting process, and the settlement value was reduced by 53.6% to 60.4%; the reasonable grouting pressure and range design avoided the waste of resources caused by excessive grouting; the grouting range was accurately controlled to achieve a balance between economy and safety; compared with the traditional solution, the cost of each special segment only increased by 10-50 yuan; the grouting volume did not increase significantly, but the effect was significantly improved; a cost-effective deformation control effect was achieved; the maximum surface settlement was reduced from 22cm to 12cm; the settlement of the left-line tunnel was reduced by 60.4%, and the settlement of the right-line was reduced by 53.6%; the construction safety and project quality were significantly improved; with only a slight increase in cost, an unexpected settlement control effect (reduced by more than 45%) was obtained

[0079] The X-shaped grouting pipe design not only improves the grouting efficiency, but also unexpectedly enhances the overall strength of the pipe segment; the synergistic effect of multi-point monitoring and dynamic parameter adjustment makes the project quality control accuracy exceed expectations.

[0080] Example 2

[0081] Reference Figure 3 - Fig.13 , which is the second embodiment of the present invention, and provides a method for controlling deformation and settlement of a stacked tunnel.

[0082] A novel stacked tunnel reinforcement method comprises the following steps:

[0083] 1) Use a shield machine to excavate the new tunnel;

[0084] 2) When assembling lining segments in new tunnel construction, special segments with newly added grouting holes in the transverse and longitudinal directions are used in the overlapping sections of the tunnel. When prefabricating the segments, grouting pipes are installed inside the segments to discharge grout through multiple holes;

[0085] 3) When there is an existing tunnel near the newly constructed tunnel, the segments above the newly constructed tunnel shall use special segments with newly added grouting holes in the horizontal and vertical directions, and the surrounding soil shall be grout-reinforced while installing the segments;

[0086] 4) During construction, simultaneous grouting reinforcement is used to ensure the stability of the stacked tunnel construction.

[0087] Among them, for the stacked shield tunnel during the shield construction process, 8 evenly distributed and symmetrical wire displacement sensor monitoring points are set on the octagonal structure support in the shield tunnel to realize the real-time dynamic monitoring of the convergence and deformation of the completed segments. It can realize real-time monitoring of the convergence and deformation values ​​of the segments in the tunnel, and determine the elliptical shape of a certain ring of the stacked shield tunnel in real time through calculation and curve fitting, realize real-time monitoring and real-time evaluation, and control the reinforcement grouting amount of the surrounding soil.

[0088] A number of monitoring points are arranged in the soil above the stacked tunnel to collect the surface settlement data at each monitoring point in real time.

[0089] Design of special segments: Compared with conventional segments, special segments have additional grouting holes in the horizontal and vertical directions. Taking the segments used in shield tunnels with a diameter of 6m as an example, when prefabricating the segments, grouting pipes are pre-buried inside the mold. The grouting pipe is made of polymer material, and the inner wall is smooth and corrosion-resistant. The grouting pipes are distributed in an X-shape inside the mold, and two grouting holes are added at each bifurcation, adding a total of 8 grouting holes. If used in shield tunnels with a larger diameter, the grouting holes of the segments can be increased as appropriate to meet the needs of tunnel reinforcement. The slurry outlet is a circular tube with a diameter of 10cm. The slurry is pumped out from the newly added grouting holes to reinforce the lateral and radial soil of the segments.

[0090] Installation of grouting pipe: The pre-buried grouting pipe is produced separately by the pipe making factory. When the pipe segment factory makes the pipe segment, the grouting pipe is first placed in the mold to fix it and the grouting hole and the grouting outlet are blocked. Then the steel bars are tied and concrete is poured in the mold for curing. After the curing is completed, the plugs of the grouting hole and the grouting outlet are removed.

[0091] Grouting is carried out into the ground through reserved grouting holes and additional grouting holes. Due to the grouting holes added to various parts of the special segments, the grouting reinforcement range is expanded compared to the smaller reinforcement angle of conventional single-hole grouting segments. The grouting reinforcement range is expanded to the soil within 3-5m line outside the segment within 180° of the tunnel arch.

[0092] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0093] Conventional shield tunnel excavation usually starts with the right line excavation, and then the shield machine is hoisted and transferred to the left line to start excavation.

[0094] According to the design of the overlapping tunnel, if the left line of the shield tunnel is at the bottom and the right line is at the top, if the right line (upward) tunnel is constructed first, then when the left line (downward) tunnel is constructed, the stratum loss caused by the shield excavation below will inevitably lead to settlement of the stratum above, that is, settlement and deformation of the right line tunnel. Therefore, the construction procedure is adjusted to construct the downward tunnel first and then the upper tunnel. This can ensure that the tunnel constructed first will not be disturbed by the later constructed tunnel and cause settlement and deformation.

[0095] During the tunneling process of the shield machine, the main working parameters of the shield machine will be calculated based on the covering depth of the shield machine in the lower tunnel and the upper tunnel combined with the construction experience, and the parameters of the shield machine will be adjusted according to the actual tunneling status during the actual tunneling process. When the sensor detects that the adjacent tunnel and the stratum have undergone large deformation, the propulsion speed and cutter head speed of the shield machine should be reduced to reduce the disturbance of the construction process to the adjacent tunnel and the surrounding stratum. Specifically, the working parameters of the shield machine include but are not limited to soil pressure, propulsion speed, cutter head speed, cutter head torque and / or thrust, etc. In some optional embodiments, the tunnel soil pressure control value is 1.2bar~2.3bar; the tunneling speed of the shield machine can be controlled at 20mm / min~40mm / min, for example; the cutter head speed can be controlled at 0.8r / min~1.2r / min, for example; the cutter head torque can be controlled at 1500KN〃m~3000KN〃m, and the cutter head thrust can be controlled at 800t~1500t. This excavation parameter is suitable for most soft soil strata and causes less disturbance to adjacent tunnels and surrounding strata.

[0096] In some optional implementation situations, the overlapping tunnel construction will be carried out first. During the construction of the lower tunnel, appropriate earthwork pressure and excavation speed will be used. Excavation parameters will be adjusted in time according to monitoring conditions. Synchronous grouting and secondary grouting will be carried out at the same time. According to the curve of surface settlement changing with excavation time, the stratum will reach its maximum uplift during excavation, and unloading will occur when the shield tail is dragged out, resulting in settlement. Therefore, during the synchronous grouting process, a water glass solution will be added to the top to reduce the initial setting time of the synchronous slurry; the secondary grouting will use double liquid slurry, and grouting reinforcement will be carried out at multiple points, multiple times, in small amounts, and evenly in layers. Cement mortar is used for synchronous grouting, and the grouting pressure is 0.5-1.0MPa. The grouting volume per ring is ≥6m 3 , secondary grouting adopts The sleeve valve pipe with t=3mm and length of 2m is injected with cement-water-glass double slurry through the pre-buried grouting hole, and the grouting pressure is 0.5-1.0MPa. After the grouting is completed, the unconfined compressive strength of the reinforced body is not less than 0.8MPa. This method is the key point of grouting in conventional projects to control deformation and settlement through grouting. Combining with the method of the present invention, a more excellent effect can be achieved.

[0097] In some optional implementations, after the interlayer soil of the overlapping tunnel is grout-reinforced by the method provided by the present invention, the surface settlement amplitude is significantly reduced. Fig.12 and Fig.13 In the finite element simulation, the deformation and settlement control method of the stacked tunnel provided by the present invention was not adopted. After the left line was connected, the settlement value reached 7.67mm. After the method provided by the present invention was adopted, the settlement value was reduced to 3.04mm, and the settlement value was reduced by 60.4%. Without the method provided by the present invention, the settlement value reached 13.73mm after the right line was connected. After the method provided by the present invention was adopted, the settlement value was reduced to 6.37mm, and the settlement value was reduced by 53.6%. It can be seen that for stacked tunnels, the deformation and settlement control method of the stacked tunnel provided by the present invention can effectively reduce surface settlement.

[0098] The control effect of the deformation and settlement control method of the overlapping tunnel provided by the present invention is significant, and the maximum settlement and deformation value of the tunnel can be controlled within the control standard value, ensuring the safety of the overlapping section of the tunnel. At the same time, the use of a reasonable grouting reinforcement range can not only ensure the safety of the overlapping tunnel construction, but also ensure the rationality of the grouting reinforcement. For some optional implementation situations, it is recommended that the radial grouting reinforcement length range is 3D to 6D, where D is the tunnel diameter. If the overlapping distance of the two tunnels is close, such as <1D, that is, the distance between the new and old tunnels is less than the tunnel diameter, the surrounding strata should adopt a larger reinforcement length, such as reinforcing the surrounding 6D strata.

[0099] The present invention proposes a method for controlling deformation and settlement of stacked tunnels. Figure 3 The conventional shield segment shown in the figure, the present invention adds grouting holes in the transverse and longitudinal directions of the segment, installs grouting pipes inside the segment when prefabricating the segment, and discharges grout through multiple holes, as shown in the attached Figure 7 As shown in the figure, in order to reduce soil settlement and ensure the structural safety of the shield tunnel built in the lower layer, grouting is carried out on the soil layer near the interlayer. A grouting pipe of a certain length (if the distance is insufficient, the length can be taken according to the actual situation) is set in the hoisting hole and the reserved grouting hole added on the arch of the pipe segment, and penetrates into the stratum. After the shield of the superimposed section tunnel passes, grouting is injected into the soil layer around the tunnel through the grouting pipe.

[0100] like Fig.12 As shown, using the deformation settlement control method of the stacked tunnel provided by the present invention, grouting holes are added at the upper pipe segment and radial grouting is performed in the soil layer. The maximum settlement of the upper soil layer of the tunnel is about 12 cm.

[0101] Comparative Example 1 Fig.13 As shown, the deformation settlement control method for the stacked tunnel provided by the present invention is not used, and only conventional synchronous grouting treatment is performed on the tunnel, and the maximum settlement of the upper soil layer of the tunnel is about 22 cm.

[0102] Based on the embodiments and comparative examples, under the same construction conditions and geological conditions, the deformation and settlement control method of the stacked tunnel provided by the present invention can reduce the settlement of the upper soil layer of the tunnel by about 45%.

[0103] Compared with the traditional construction method, the present invention effectively controls the deformation and settlement in the construction of the stacked tunnel. Figure 1 Compared with the traditional shield segments, only special segments with additional grouting holes need to be used on the upper part. Compared with ordinary segments, special segments have more grouting pipes with grouting outlets pre-buried inside. According to the market price, the cost of a single special segment increases by 10-50 yuan depending on the size of the segment. The additional grouting volume is controlled separately according to the size of the settlement. Due to the additional grouting holes, the slurry diffusion is more uniform, the settlement control effect is better, and the amount of slurry used is not significantly increased compared with the traditional reinforcement method. Combining the above two points, the present invention does not significantly increase the cost while achieving better results compared with the traditional method. Figure 6-8 The principle of grouting by adding grouting holes and the scope of reinforced soil layers are shown. Fig. 9 and Fig.10 It can be seen from the comparison that the deformation settlement control method of the stacked tunnel provided by the present invention can reduce the settlement of the upper stratum during the stacked tunnel construction process by about 45%.

[0104] The present invention provides a method for controlling deformation and settlement of stacked tunnels. In view of the adverse effects of stacked tunnel construction on the existing tunnel structure, which produces large displacement and stress, special segments with newly added grouting holes in the horizontal and vertical directions are used in the overlapping sections of the tunnel on the basis of existing shield segments. Grouting pipes are installed inside the segments during prefabrication, and grout is discharged through multiple holes to achieve the purpose of controlling the displacement and adverse stress of the existing tunnel. Compared with the prior art, the reinforcement method proposed by the present invention can effectively control the settlement and adverse stress of the completed tunnel, and the construction difficulty and cost are not significantly increased.

[0105] Example 3

[0106] Reference Figure 2 - Fig.13 , which is the third embodiment of the present invention, provides a method for controlling deformation and settlement of a stacked tunnel. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0107] This embodiment selects the intersection section of a certain city rail transit line 4 and line 1 as the test section. This section is located in the soft soil layer, and the geological conditions are: the surface layer is miscellaneous fill (0-3m), and the underlying silty clay (3-8m), silty soil (8-15m), and fine sand (15-25m). The diameter of the test section tunnel is 6.2m, the burial depth is 18m, and the minimum clear distance between the two tunnels is 0.8D (D is the outer diameter of the tunnel). In order to verify the effectiveness of the method of the present invention, the test section is divided into two sections, A and B, each with a length of 100m. Section A adopts the control method of the present invention, and section B adopts the traditional construction method.

[0108] Section A is constructed with special segments, 35cm thick, and cast with C50 concrete. When prefabricating the segments, a polymer composite material (polyethylene, 2mm wall thickness) is used to make an X-shaped grouting pipe network, with a pipe main diameter of 45mm and a branch pipe diameter of 30mm. 8 slurry outlet holes with a diameter of 100mm are pre-buried at the slurry outlet points, and the inner wall of the slurry outlet hole is treated with Teflon coating to prevent slurry solidification and clogging. The grouting pipe network is fixed with a positioning frame when prefabricated in the factory to ensure that the position does not shift during the pouring process. The concrete vibration uses low-frequency (45Hz) vibration to avoid damage to the pipe network.

[0109] A set of displacement monitoring sensors (accuracy 0.01mm) is arranged every 2m within the 120° range of the tunnel vault, and a set of soil pressure boxes (measurement range 0-2MPa) is buried every 5m in the soil around the tunnel. The monitoring data is uploaded to the construction control center in real time through the wireless transmission module.

[0110] During the construction process, the shield tunneling parameters are strictly controlled according to the settings: when the soil pressure sensor shows that the formation pressure exceeds 1.3bar, the tunneling speed is reduced from 20mm / min to 15mm / min, and the cutter head speed is reduced from 0.8r / min to 0.6r / min. The synchronous grouting uses a two-component slurry (cement slurry + water glass), with a slurry ratio of 0.8 cement slurry water-cement ratio and a water glass Baume degree of 38°. The grouting pressure is maintained at 0.8MPa through an intelligent pressure control system. When the deformation of the pipe segment exceeds 2mm, the grouting volume is automatically increased by 20%.

[0111] The secondary grouting uses micro-expansion cement slurry, and the expansion rate is controlled within 0.02% in 28 days. It is injected in 4 times through the X-type grouting pipe network, with an interval of 12 hours between each grouting, and a single grouting volume of 2.0m 3 During the grouting process, a real-time ultrasonic detection system is used to monitor the grouting fullness, and the grouting is stopped when the fullness reaches 95%.

[0112] Test data comparison

[0113]

[0114] Through detailed monitoring and data analysis of the construction process of sections A and B, the method of the present invention shows significant advantages in multiple key performance indicators:

[0115] Deformation Control Effect:

[0116] In section A using the method of the present invention, the maximum surface settlement is only 8.6 mm, which is 59.8% lower than the 21.4 mm of the traditional method. More importantly, the width of the surface settlement trough is reduced from 25.6 m to 18.2 m, indicating that the method of the present invention not only controls the amount of settlement, but also effectively reduces the scope of settlement influence. This effect is due to the uniform grouting of the X-type grouting network and the precise control of the real-time monitoring feedback system.

[0117] Structural stability:

[0118] The vault settlement and horizontal convergence of the upper tunnel were 5.2mm and 4.1mm, respectively, which were 59.4% and 57.3% lower than those of the traditional method. In particular, the maximum opening value of the segment joint was only 0.8mm, much lower than the 2.3mm of the traditional method, which fully demonstrated the structural advantages of the special segment and the effectiveness of the grouting system. By comparing the data, it can be found that the method of the present invention keeps the tunnel structure in a state of small deformation, effectively avoiding the occurrence of cumulative deformation.

[0119] Reinforcement effect:

[0120] The soil grouting fullness obtained by the method of the present invention reaches 95.6%, which is much higher than the 82.4% of the traditional method. The unconfined compressive strength of the reinforced soil reaches 1.2MPa, which is twice that of the traditional method. This significant improvement is due to the uniform distribution of the X-shaped grouting pipe network and the synergistic effect of multi-point grouting, which realizes the all-round reinforcement of the surrounding soil. The high fullness and strength not only ensure the construction safety, but also provide reliable guarantee for the later operation.

[0121] Economic benefits:

[0122] Although the production cost of the special segment is slightly higher, the grouting material consumption of Section A is reduced by 15.3% compared with the traditional method by optimizing the grouting process. At the same time, thanks to the automated control system and optimized construction process, the construction progress is increased by 16.7%. In comprehensive calculation, the total construction cost of Section A is reduced by 7.7% compared with the traditional method, reflecting good economic efficiency.

[0123] Unexpected effects:

[0124] During the construction process, it was found that the method of the present invention not only achieved the expected deformation control target, but also brought some unexpected positive effects. For example, through real-time monitoring and automatic control systems, the common problem of over-grouting in traditional construction was effectively avoided, which not only saved materials but also avoided disturbance to the surrounding strata. At the same time, the existence of the X-shaped grouting network improved the integrity of the pipe segment, making the pipe segment show better toughness during the stress process, which was a favorable effect that was not foreseen at the beginning of the design.

[0125] In summary, through actual engineering tests, the method of the present invention has shown significant advantages in deformation control, structural stability, reinforcement effect and economic benefits, which fully verifies its innovation and practical value. In particular, the significant improvement in grouting effect and deformation control provides reliable technical support for similar projects.

[0126] Example 3

[0127] This embodiment also provides a computer device, which is applicable to a forced oscillation detection and positioning method for a distribution network, including a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement a forced oscillation detection and positioning method for a distribution network as proposed in the above embodiment.

[0128] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0129] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0130] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0131] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering, or processing in another suitable manner as necessary, and then stored in a computer memory.

[0132] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0133] This embodiment further provides a storage medium on which a computer program is stored. When the program is executed by a processor, a forced oscillation detection and positioning method for a distribution network is implemented as proposed in the above embodiment.

[0134] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for controlling deformation and settlement of a stacked tunnel, characterized in that: include, Before the construction of the stacked tunnel, construction preparation and deployment are carried out, and monitoring points are set up in the upper soil of the shield tunnel; Tunnel construction is carried out using special segments, wherein the special segments are provided with grouting holes and pre-buried grouting pipes in the transverse and longitudinal directions; Real-time monitoring of deformation and settlement during the construction of the stacked tunnel to obtain monitoring data; During the shield construction process, construction parameters are adjusted in real time according to monitoring data and grouting reinforcement is carried out.

2. A method for controlling deformation and settlement of a stacked tunnel according to claim 1, characterized in that: The grouting pipes of the special pipe segment are made of polymer materials and are distributed in an X-shape inside the pipe segment. Two additional slurry outlet holes are set at each bifurcation, totaling 8 slurry outlet holes; The slurry outlet hole is a circular tube with a diameter of 10 cm, which is used to reinforce the lateral and radial soil of the pipe segment.

3. A method for controlling deformation and settlement of a stacked tunnel as claimed in claim 2, characterized in that: The installation of the grouting pipe includes: when manufacturing the pipe segment in the pipe segment factory, firstly, placing the grouting pipe in the mold, fixing it and plugging the grouting hole and the grouting outlet; Tie up the steel bars and pour concrete in the mold for curing; after curing is completed, remove the plugs from the grouting holes and outlets.

4. A method for controlling deformation and settlement of a stacked tunnel as claimed in claim 3, characterized in that: The shield construction parameters include: tunnel soil pressure control value is 1.2 bar; shield machine excavation speed is controlled at 20 mm / min; cutter head speed is controlled at 0.8 r / min; cutter head torque is controlled at 3000 KN·m; cutter head thrust is controlled at 800t~1500t.

5. A method for controlling deformation and settlement of a stacked tunnel as claimed in claim 4, characterized in that: The grouting reinforcement includes synchronous grouting and secondary grouting; The synchronous grouting adopts cement mortar, the grouting pressure is 0.5~1.0MPa, and the grouting volume per ring is ≥6m 3 ; The secondary grouting uses a sleeve valve pipe with a diameter of 38, t=3mm and a length of 2m, and injects cement-water-glass double liquid slurry through the pre-buried grouting hole. The grouting pressure is 0.5-1.0MPa. After grouting is completed, the unconfined compressive strength of the reinforced body shall not be less than 0.8MPa.

6. A method for controlling deformation and settlement of a stacked tunnel as claimed in claim 5, characterized in that: The grouting reinforcement range is the soil within the 3-5m line outside the segment within 180° of the tunnel arch; When the overlapping distance of two tunnels is less than the tunnel diameter, the surrounding strata should be reinforced to a range of 6 times the tunnel diameter; The radial grouting reinforcement length is 3D to 6D, where D is the tunnel diameter; when the distance between the new and old tunnels is less than the tunnel diameter, the reinforcement length is 6D.

7. A method for controlling deformation and settlement of a stacked tunnel as claimed in claim 6, characterized in that: The construction is carried out according to the following steps: firstly carry out the down tunnel construction, and then carry out the upper tunnel construction, so as to ensure that the tunnel constructed first is not disturbed by the later tunnel construction and does not undergo settlement and deformation; Dynamically adjust construction parameters based on monitoring data. When large deformation is detected, reduce the shield machine's propulsion speed and cutterhead speed. During the tunneling process of the shield machine, the operating parameters of the shield machine are calculated and adjusted according to the cover depth.

8. A deformation and settlement control system for a stacked tunnel, based on a deformation and settlement control method for a stacked tunnel according to any one of claims 1 to 7, characterized in that: Also includes, Deployment module: Before the construction of the stacked tunnel, construction preparation and deployment are carried out, and monitoring points are set up in the upper soil of the shield tunnel; Construction module, using special segments for tunnel construction, the special segments are provided with grouting holes and pre-buried grouting pipes in the horizontal and vertical directions; Monitoring module, real-time monitoring of deformation and settlement during the construction of the stacked tunnel, and acquisition of monitoring data; The grouting module adjusts the construction parameters in real time according to the monitoring data and performs grouting reinforcement during the shield construction process.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for controlling deformation and settlement of a stacked tunnel as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a method for controlling deformation and settlement of a stacked tunnel as described in any one of claims 1 to 7 are implemented.

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