A deformation dynamic control method for a single-hole double-layer tunnel crossing road

Abstract

The present application relates to a kind of single-hole double-layer tunnel crossing road deformation dynamic control method, comprising: obtaining the positional relationship of crossing tunnel and road, crossing tunnel and road municipal pipeline;Formulate construction measures based on positional relationship, and obtain the deformation law of single-layer double-hole tunnel crossing road under construction measures by construction simulation;The construction process is divided into first stage and second stage, and the dynamic deformation control value of road in first stage and second stage is calculated based on deformation law, and first deformation control early warning threshold and second deformation control early warning threshold are set based on the dynamic deformation control value of road;The dynamic deformation of road in the construction process of first stage and second stage is real-time early warning respectively through first deformation control early warning threshold and second deformation control early warning threshold, and construction measures are adjusted according to early warning result.The present application can more accurately control the deformation caused by tunnel crossing road by studying deformation law for two-stage dynamic control, and ensure the safety of road structure.

Description

Technical Field

[0001] This invention relates to the field of safety evaluation technology for tunnels crossing roads, and in particular to a dynamic deformation control method for a single-hole double-layer tunnel crossing a road. Background Technology

[0002] When a tunnel crosses a road, the excavation process causes ground deformation. If the deformation exceeds the road engineering deformation control value, it can lead to adverse effects such as tunnel collapse, roadbed subsidence, road surface cracking, and rupture of municipal pipelines. This not only damages the infrastructure of the road or municipal pipelines but also affects the driving safety of the road.

[0003] Power lines are often laid out in single-bore, double-layer tunnels. The construction method for single-bore, double-layer tunnels involves construction of the upper layer and the lower layer. In road crossing projects, to protect the road structure, three construction measures are commonly adopted: first, increasing the spacing of the tunnel support grid; second, using curtain grouting to reinforce the soil around the tunnel; and third, using anchor bolts to ensure the stability of the soil arch. In such complex situations, different construction methods for the same soil often overlap. For example, before excavating the upper layer, grouting is performed within a certain range outside the upper tunnel outline. After the initial support of the upper tunnel is completed, before excavating the lower tunnel, the grouted soil within the lower tunnel excavation area must be removed. Furthermore, the excavation is also divided into two stages: upper excavation and lower excavation. This construction method causes greater soil disturbance than single-bore, single-tunnel construction, making the situation more complex. How to control the deformation caused by single-bore, double-layer tunnels crossing roads is a problem that urgently needs to be solved.

[0004] Currently, deformation control of single-hole double-layer tunnels crossing roads mainly focuses on controlling the final value of the control value. Once the deformation warning value is reached, it may be too late to take measures. Therefore, in order to control deformation more accurately, a dynamic deformation control method for single-hole double-layer tunnels crossing roads is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a dynamic control method for the deformation of a single-hole double-layer tunnel crossing a road. By studying the deformation law and performing two-stage dynamic control, the deformation caused by the tunnel crossing the road can be controlled more accurately, thus ensuring the safety of the road structure.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for dynamic deformation control of a single-bore, double-layer tunnel crossing a road includes:

[0008] Obtain the locational relationship between tunnels and roads, and between tunnels and municipal pipelines along roads;

[0009] Based on the aforementioned location relationship, construction measures were formulated, and the deformation pattern of a single-layer double-hole tunnel crossing a road under the aforementioned construction measures was obtained through construction simulation.

[0010] The construction process is divided into a first stage and a second stage. Based on the deformation law, the dynamic deformation control values ​​of the road in the first stage and the second stage are calculated. Based on the dynamic deformation control values ​​of the road, a first deformation control early warning threshold and a second deformation control early warning threshold are set.

[0011] The dynamic deformation of the road during the first and second stages of construction is given real-time warnings using the first deformation control warning threshold and the second deformation control warning threshold, respectively. The construction measures are adjusted according to the warning results to complete the dynamic deformation control of the single-layer double-hole tunnel crossing the road.

[0012] Optionally, obtaining the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines along the road, includes:

[0013] The analysis of the road crossing overview determines the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines. The road crossing overview includes the road overview and the single-bore double-layer tunnel overview. The road overview includes the road grade, road cross-sectional layout, road structure, and road ancillary facilities. The single-bore double-layer tunnel overview includes the tunnel's horizontal alignment, tunnel cross-sectional form, tunnel longitudinal section, tunnel geological conditions, tunnel depth, and overburden.

[0014] Optionally, formulating the construction measures based on the location relationship includes:

[0015] Based on the aforementioned location relationships, and considering road safety, the aforementioned construction measures were formulated.

[0016] Construction simulation was conducted using finite element analysis to obtain the deformation characteristics of a single-layer double-hole tunnel crossing a road under the aforementioned construction measures.

[0017] If the deformation pattern satisfies road safety requirements, then the construction measures are determined.

[0018] If the deformation pattern does not meet road safety requirements, the construction measures shall be adjusted until road safety is met, and then the construction measures shall be determined.

[0019] Optionally, construction simulation is performed using finite element analysis to obtain the deformation characteristics of a single-layer, double-hole tunnel crossing a road under the aforementioned construction measures, including:

[0020] A three-dimensional construction model was established using finite element analysis software. The three-dimensional construction model includes soil, working shaft, receiving shaft, and tunnel.

[0021] Based on the aforementioned construction measures, a construction simulation was performed on the three-dimensional construction model, and the surface deformation patterns during the simulation process were recorded.

[0022] Optionally, the construction process of a single-layer double-hole tunnel crossing a road can be divided into the construction processes of the upper and lower tunnels. The first stage consists of grouting and reinforcement of the soil around the upper tunnel, excavation of the soil in the upper tunnel, and completion of the initial support of the upper tunnel. The second stage consists of grouting and reinforcement of the soil around the lower tunnel, excavation of the soil in the lower tunnel, completion of the initial support of the lower tunnel, completion of the secondary lining of the lower tunnel, and completion of the secondary lining of the upper tunnel.

[0023] Optionally, the method for calculating the road dynamic deformation control values ​​for the first and second stages based on the deformation law is as follows:

[0024]

[0025] C2 = S

[0026] Wherein, C1--control value of surface deformation in the first stage, C2--control value of surface deformation in the second stage; δ1---surface deformation value after the completion of grouting reinforcement of the soil around the upper tunnel; δ6---cumulative surface deformation value after the completion of the secondary lining of the upper tunnel; S--control value of road structure deformation.

[0027] Optionally, real-time early warning of road dynamic deformation during the first and second stages of construction is provided using the first deformation control early warning threshold and the second deformation control early warning threshold, respectively, and the construction measures are adjusted based on the early warning results, including:

[0028] During the first phase of construction, the measured dynamic deformation value of the first road is monitored in real time. If the measured dynamic deformation value of the first road reaches the first deformation control warning threshold, work is immediately stopped and the corresponding construction measures are adjusted. If the measured dynamic deformation value of the first road does not reach the first deformation control warning threshold by the end of the first phase of construction, the second phase of construction begins. During the second phase of construction, the measured dynamic deformation value of the second road is monitored in real time. If the measured dynamic deformation value of the second road reaches the second deformation control warning threshold, work is immediately stopped and the corresponding construction measures are adjusted. If the measured dynamic deformation value of the second road does not reach the second deformation control warning threshold by the end of the second phase of construction, the construction is completed.

[0029] The beneficial effects of this invention are as follows:

[0030] The present invention proposes a dynamic deformation control method for single-hole double-layer tunnels crossing roads. By studying the deformation law, the road deformation control value is divided into two stages. Compared with the previous control based on the final deformation value, this method is more scientific and reasonable, and can more accurately control the deformation caused by the tunnel crossing the road, ensuring the safety of the road structure. If the first stage exceeds the warning value, the construction plan is immediately adjusted or work is stopped. The construction unit and the contractor can detect and solve problems earlier, thereby avoiding the occurrence of safety accidents. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a flowchart of a method for dynamic deformation control of a single-hole double-layer tunnel crossing a road, according to an embodiment of the present invention.

[0033] Figure 2 This is a cross-sectional view of a single-hole double-layer tunnel according to an embodiment of the present invention;

[0034] Figure 3 This is a construction process diagram of a single-hole double-layer tunnel crossing a road according to an embodiment of the present invention. (a) shows grouting reinforcement of the soil around the upper tunnel; (b) shows excavation of the soil in the upper tunnel with initial support completed; (c) shows grouting reinforcement of the soil around the lower tunnel; (d) shows excavation of the soil in the lower tunnel with initial support completed; (e) shows completion of the secondary lining of the lower tunnel; (f) shows completion of the secondary lining of the upper tunnel. Ⅰ-First part of the soil in the upper tunnel; Ⅱ-Second part of the soil in the upper tunnel; Ⅲ-First part of the soil in the lower tunnel; Ⅳ-Second part of the soil in the lower tunnel.

[0035] Figure 4 This is a cross-sectional view of the road crossing Yaojiayuan Road according to an embodiment of the present invention;

[0036] Figure 5 The following are vertical deformation cloud diagrams during the construction process simulation stage of this invention embodiment: (a) is the vertical deformation cloud diagram of the stress balance of the double-layer tunnel, (b) is the vertical deformation cloud diagram of the vehicle load, (c) is the vertical deformation cloud diagram of the upper grouting, (d) is the vertical deformation cloud diagram of the upper excavation and initial support, (e) is the vertical deformation cloud diagram of the lower grouting, (f) is the vertical deformation cloud diagram of the lower excavation and initial support, (g) is the vertical deformation cloud diagram of the lower secondary lining, and (h) is the vertical deformation cloud diagram of the upper secondary lining.

[0037] Figure 6 This illustrates the vertical displacement distribution during the construction process simulation phase of this invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] This embodiment provides a method for dynamic deformation control of a single-hole, double-layer tunnel crossing a road, including:

[0041] Obtain the locational relationship between tunnels and roads, and between tunnels and municipal pipelines along roads;

[0042] Construction measures were formulated based on location relationships, and the deformation patterns of a single-layer double-hole tunnel crossing a road were obtained through construction simulation.

[0043] The construction process is divided into a first stage and a second stage. Based on the deformation law, the dynamic deformation control values ​​of the road in the first and second stages are calculated, and a first deformation control early warning threshold and a second deformation control early warning threshold are set based on the dynamic deformation control values ​​of the road.

[0044] The dynamic deformation of the road during the first and second stages of construction is monitored in real time by using the first deformation control warning threshold and the second deformation control warning threshold respectively. Based on the warning results, the construction measures are adjusted to achieve dynamic deformation control of the single-layer double-hole tunnel crossing the road.

[0045] like Figure 1 As shown, the control method provided in this embodiment specifically includes:

[0046] S1. Analyze the general situation of the road crossing project and obtain the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines.

[0047] The road crossing information is mainly divided into road overview and single-bore double-layer tunnel overview. As shown in Table 1, the road overview includes basic information such as road grade, cross-sectional layout, structural form, and ancillary facilities. The single-bore double-layer tunnel overview includes tunnel alignment, cross-sectional form, longitudinal section, geological conditions, burial depth, and overburden. Based on the road overview and the single-bore double-layer tunnel overview, the locational relationship between the tunnel and the road, and the locational relationship between the tunnel and municipal pipelines, are determined. These basic information forms the basis for determining the risk level of the crossing project.

[0048] Table 1

[0049]

[0050]

[0051] S2. Determine construction measures to protect road safety based on location relationships;

[0052] Cross-sectional diagram of a single-hole double-layer tunnel as shown below Figure 2 As shown, in order to ensure the construction safety of a single-hole double-layer tunnel crossing a road, the construction measures to protect the road safety are determined based on the geological conditions, the backfill of the road crossing project, and the clearance from municipal pipelines. Generally, the following three construction measures are adopted: First, the spacing of the tunnel support grid is increased; second, curtain grouting is used to reinforce the soil around the tunnel; and third, anchor bolts are used to ensure the stability of the soil arch.

[0053] S3. Study the deformation law of single-layer and double-layer tunnels crossing roads under construction measures through construction simulation;

[0054] A three-dimensional model including the soil, working shaft, receiving shaft, and tunnel was established using the finite element method software Midas-GTS to analyze the impact of construction on the road. The soil was modeled using the Mohr-Coulomb constitutive model, while the working shaft, receiving shaft, and tunnel were simulated using elastic solid elements.

[0055] The construction process of a single-bore double-layer tunnel crossing a road is as follows: Figure 3 As shown, (a) is the grouting reinforcement of the soil around the upper tunnel, (b) is the excavation of the soil in the upper tunnel and the completion of the initial support, (c) is the grouting reinforcement of the soil around the lower tunnel, (d) is the excavation of the soil in the lower tunnel and the completion of the initial support, (e) is the completion of the secondary lining of the lower tunnel, and (f) is the completion of the secondary lining of the upper tunnel.

[0056] The excavation of the upper tunnel soil is carried out in two parts. First, the first part of the upper tunnel soil I is excavated, the core soil is retained, the top and side initial lining grids are erected, and sprayed concrete is applied. Then, the second part of the upper tunnel soil II is excavated, the top and side initial lining grids are erected, sprayed concrete is applied, the upper pilot tunnel initial lining structure is closed, and the initial support is completed.

[0057] Similarly, the excavation of the lower tunnel soil was also carried out in two parts. First, the first part of the lower tunnel soil III was excavated, the core soil was retained, the top and side initial lining grids were erected, and sprayed concrete was applied. Then, the second part of the lower tunnel soil IV was excavated, the top and side initial lining grids were erected, sprayed concrete was applied, the lower pilot tunnel initial lining structure was closed, and the initial support was completed.

[0058] Based on the construction process of the single-hole double-layer tunnel crossing the road and similar engineering construction experience, and considering the most adverse impact of construction on the roadbed, the construction process simulation is divided into the following working conditions:

[0059] (1) Construction process simulation step 1: Ground stress balance;

[0060] (2) Construction process simulation step 2: Excavation of working wells at both ends;

[0061] (3) Construction process simulation step 3: upper grouting;

[0062] (4) Construction process simulation step 4: upper excavation, initial support completed;

[0063] (5) Simulation of construction process step 5: lower grouting;

[0064] (6) Construction process simulation step 6: lower excavation, initial support completed;

[0065] (7) Construction process simulation step 7: lower secondary lining completed;

[0066] (8) Construction process simulation step 8: The upper secondary lining is completed.

[0067] Record the following values ​​in the simulated construction process: δ1---Surface deformation value after the completion of upper grouting; δ2---Cumulative surface deformation value after the completion of upper excavation and initial support; δ3---Cumulative surface deformation value after the completion of lower grouting; δ4---Cumulative surface deformation value after the completion of lower excavation and initial support; δ5---Cumulative surface deformation value after the completion of lower secondary lining; δ6---Cumulative surface deformation value after the completion of upper secondary lining.

[0068] Based on the simulated construction process steps, the construction process is divided into two stages: Stage 1: Grouting and reinforcement of the soil around the upper tunnel, excavation of the upper tunnel soil, and completion of the initial support of the upper tunnel; Stage 2: Grouting and reinforcement of the soil around the lower tunnel, excavation of the lower tunnel soil, completion of the initial support of the lower tunnel, and completion of the secondary lining of both tunnels. The deformation in the two stages is analyzed based on the simulation results.

[0069] S4. Determine the dynamic deformation control value of the road based on the deformation law;

[0070] First-stage deformation control values:

[0071] First-stage deformation control value: C2 = S;

[0072] Among them, C1 is the control value of surface deformation in the first stage; C2 is the control value of surface deformation in the second stage; S is the control value of road structure deformation, which is based on the local standard "Technical Requirements for Engineering of Facilities Crossing Existing Roads".

[0073] S5, deformation monitoring and dynamic deformation control;

[0074] Based on the road dynamic deformation control values, a first deformation control early warning threshold and a second deformation control early warning threshold are set. Real-time early warnings of road dynamic deformation during the first and second stages of construction are provided using these thresholds, respectively. Construction measures are adjusted based on the early warning results. The specific control process includes:

[0075] During the first phase of construction, the measured values ​​of dynamic deformation of the first road are monitored in real time. If the measured values ​​of dynamic deformation of the first road reach the first deformation control warning threshold, construction will be stopped immediately and the corresponding construction measures will be adjusted. If the measured values ​​of dynamic deformation of the first road do not reach the first deformation control warning threshold by the end of the first phase of construction, the second phase of construction will begin.

[0076] During the second phase of construction, the measured values ​​of dynamic deformation of the second road will be monitored in real time. If the measured values ​​of dynamic deformation of the second road reach the second deformation control warning threshold, construction will be stopped immediately and the corresponding construction measures will be adjusted. If the measured values ​​of dynamic deformation of the second road do not reach the second deformation control warning threshold by the end of the second phase of construction, the construction will be completed.

[0077] The following is a detailed description of the control method proposed in this embodiment, taking the dynamic control of road deformation when the CBD 500 kV transmission and transformation project (power transmission section) (section 5) crosses Yaojiayuan Road as an example:

[0078] S1. Overview of the road crossing project, and obtain the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines.

[0079] The CBD 500kV power transmission project's cable tunnel starts from the planned CBD 500kV substation. The starting point connects with the tunnel inside the substation on the north side, then runs north through the planned East-West Street of the business center before turning east. A new 2600×5500 mm single-hole double-layer cable tunnel is built 3-5 meters north along the east side of Yongzhong Road of Tuanjiehu Road, reaching Chaoyang Park South Road, where it connects with the planned integrated utility tunnel of Metro Line 3.

[0080] The technical specifications for Yaojiayuan Road are as follows:

[0081] 1) Road design grade: Urban arterial road;

[0082] 2) Road width: 40 meters;

[0083] 3) Design speed: 40 km / h;

[0084] 4) Road cross-sectional layout as follows Figure 4 As shown, the width of Yaojiayuan Road from north to south is: 8.0m (sidewalk) + 2.4m (non-motorized vehicle lane) + 2.0m (median strip) + 15.5m (motorized vehicle lane) + 2.0m (median strip) + 2.4m (non-motorized vehicle lane) + 8.1m (sidewalk).

[0085] Road pavement structure:

[0086] The surface layer is 4 cm thick and made of fine-grained asphalt concrete AC-13C.

[0087] The bottom layer is 6 cm thick, made of medium-grained asphalt concrete AC-20C;

[0088] The upper base layer is 18 cm thick, consisting of lime, fly ash, and crushed stone.

[0089] The lower layer is 18 cm thick, consisting of lime, fly ash, and crushed stone.

[0090] The base layer is 18 cm thick and consists of lime, fly ash, and crushed stone.

[0091] Total thickness 64 cm.

[0092] The shallowest overburden at the point where it crosses Yaojiayuan Road is 8.3m deep, passing through three layers of fine sand. The groundwater level distribution is as follows: Figure 4 As shown.

[0093] S2. Determine construction measures to protect road safety based on location relationships;

[0094] To ensure construction safety when a single-hole double-layer tunnel crosses a road, construction measures to protect road safety are determined based on geological conditions, the backfill of the road crossing project, and the clearance from municipal pipelines. The following three construction measures are adopted in this project: First, the spacing of the tunnel support grid is increased to 0.5m; second, curtain grouting is used to reinforce the soil around the tunnel, with the reinforcement range being 1.5m around the tunnel; and third, anchor bolts are used to ensure the stability of the soil arch.

[0095] The determination of the above construction measures provides the scope of soil reinforcement for the next step of deformation law analysis, which is a 1.5m range of soil around the tunnel; the spacing of the tunnel support grid is increased to enhance the strength of the simulated tunnel primary support and secondary lining.

[0096] S3. Study the deformation law of single-layer and double-layer tunnels crossing roads under construction measures through construction simulation;

[0097] A three-dimensional model including the soil, working shaft, receiving shaft, and tunnel was established using the finite element method software Midas-GTS to analyze the impact of construction on the road. The soil was modeled using the Mohr-Coulomb constitutive model, while the working shaft, receiving shaft, and tunnel were simulated using elastic solid elements. The physical and mechanical parameters of the soil used in the calculations are available in the geological survey report.

[0098] The model's dimensions along the X, Y, and Z directions are 320m, 120m, and 38m, respectively, where X represents the tunnel excavation direction, Y represents the direction perpendicular to the tunnel, and Z represents the vertical direction.

[0099] Based on the design scheme and similar engineering construction experience, and considering the most adverse effects of construction on the roadbed, the construction process is divided into the following working conditions.

[0100] (1) Construction process simulation step 1: Ground stress balance;

[0101] (2) Construction process simulation step 2: Excavation of working wells at both ends;

[0102] (3) Construction process simulation step 3: upper grouting;

[0103] (4) Construction process simulation step 4: upper excavation, initial support completed;

[0104] (5) Simulation of construction process step 5: lower grouting;

[0105] (6) Construction process simulation step 6: lower excavation, initial support completed;

[0106] (7) Construction process simulation step 7: lower secondary lining completed;

[0107] (8) Construction process simulation step 8: The upper secondary lining is completed.

[0108] After calculation and analysis, the vertical deformation cloud maps for each simulation stage are as follows: Figure 5 As shown, where, Figure 5 (a) is the vertical deformation cloud diagram of the stress balance of the double-layer tunnel, (b) is the vertical deformation cloud diagram of the vehicle load, (c) is the vertical deformation cloud diagram of the upper grouting, (d) is the vertical deformation cloud diagram of the upper excavation and initial support, (e) is the vertical deformation cloud diagram of the lower grouting, (f) is the vertical deformation cloud diagram of the lower excavation and initial support, (g) is the vertical deformation cloud diagram of the lower secondary lining, and (h) is the vertical deformation cloud diagram of the upper secondary lining.

[0109] The vertical deformation distribution of the road surface in each simulation stage is as follows: Figure 6 As shown, after the initial support of the upper tunnel excavation is completed, the maximum settlement of the road surface is 6.3 mm; after the initial support of the lower tunnel excavation is completed, the maximum settlement of the road surface is 8.9 mm; after the secondary lining of the lower tunnel is completed, the maximum settlement of the road surface is 9.1 mm; and after the secondary lining of the upper tunnel is completed, the maximum settlement of the road surface is 9.2 mm.

[0110] Based on the deformation law, the construction process is mainly divided into two stages: the first stage is the grouting and reinforcement of the soil around the upper tunnel, the excavation of the soil around the upper tunnel, and the completion of the initial support of the upper tunnel; the second stage is the grouting and reinforcement of the soil around the lower tunnel, the excavation of the soil around the lower tunnel, the completion of the initial support of the lower tunnel, and the completion of the secondary lining of both the upper and lower tunnels.

[0111] S4. Determine the dynamic deformation control value of the road based on the deformation law;

[0112] The road structure deformation control values ​​obtained according to the Beijing local standard "Technical Requirements for Engineering Facilities Crossing Existing Roads" are shown in Table 2.

[0113] Table 2

[0114]

[0115]

[0116] Calculate the road dynamic deformation control values ​​for the two stages:

[0117] Phase 1:

[0118] Second stage: C2 = 15.

[0119] S5, deformation monitoring and dynamic deformation control;

[0120] Table 3 shows the first and second deformation control early warning thresholds for a single-hole double-layer tunnel crossing a road, based on the dynamic deformation control values ​​of the road.

[0121] Table 3

[0122]

[0123] After construction begins, the measured values ​​of dynamic deformation of the first road during the first phase of construction will be monitored. If the measured values ​​of dynamic deformation of the first road reach the first deformation control warning threshold (i.e., road surface heave reaches 3mm or road surface settlement reaches 10mm), then more frequent monitoring will be implemented, support parameters will be optimized, excavation progress will be adjusted, and process methods will be improved, or even work will be suspended. If the measured values ​​of dynamic deformation of the first road do not reach the first deformation control warning threshold by the end of the first phase of construction, then the second phase of construction will commence.

[0124] After the start of the second phase of construction, the measured values ​​of dynamic deformation of the second road will be monitored during the construction process. If the measured values ​​of dynamic deformation of the second road reach the second deformation control warning threshold (i.e., the road surface heave reaches 5mm or the road surface settlement reaches 15mm), then more frequent monitoring will be implemented, support parameters will be optimized, excavation progress will be adjusted, and process methods will be improved, or even work will be suspended. If the measured values ​​of dynamic deformation of the second road do not reach the second deformation control warning threshold by the end of the second phase of construction, then the construction is considered complete.

[0125] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for dynamic deformation control of a single-hole, double-layer tunnel crossing a road, characterized in that, include: Obtain the locational relationship between tunnels and roads, and between tunnels and municipal pipelines along roads; Based on the aforementioned location relationship, construction measures were formulated, and the deformation pattern of a single-hole double-layer tunnel crossing a road under the aforementioned construction measures was obtained through construction simulation. The construction process is divided into two stages: the construction process of the single-hole double-layer tunnel crossing the road is divided into the construction process of the upper tunnel and the lower tunnel. The first stage consists of grouting and reinforcement of the soil around the upper tunnel, excavation of the soil in the upper tunnel, and completion of the initial support of the upper tunnel. The second stage consists of grouting and reinforcement of the soil around the lower tunnel, excavation of the soil in the lower tunnel, completion of the initial support of the lower tunnel, completion of the secondary lining of the lower tunnel, and completion of the secondary lining of the upper tunnel. Based on the aforementioned deformation pattern, calculate the road dynamic deformation control values ​​for the first and second stages: C1 = ×S C2=S Wherein, C1 is the control value for surface deformation in the first stage, and C2 is the control value for surface deformation in the second stage; --Surface deformation value after the grouting reinforcement of the soil around the upper tunnel is completed; --Cumulative surface deformation value after the completion of the secondary lining of the upper tunnel; S--Road structure deformation control value; And based on the road dynamic deformation control values, a first deformation control early warning threshold and a second deformation control early warning threshold are set; The dynamic deformation of the road during the first and second stages of construction is given real-time warnings using the first deformation control warning threshold and the second deformation control warning threshold, respectively. The construction measures are adjusted according to the warning results to complete the dynamic deformation control of the single-hole double-layer tunnel crossing the road.

2. The deformation dynamic control method for a single-hole double-layer tunnel crossing a road according to claim 1, characterized in that, Obtaining the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines along the road, includes: The analysis of the road crossing overview determines the positional relationship between the tunnel and the road, and between the tunnel and the municipal pipelines. The road crossing overview includes the road overview and the single-bore double-layer tunnel overview. The road overview includes the road grade, road cross-sectional layout, road structure, and road ancillary facilities. The single-bore double-layer tunnel overview includes the tunnel's horizontal alignment, tunnel cross-sectional form, tunnel longitudinal section, tunnel geological conditions, tunnel depth, and overburden.

3. The deformation dynamic control method for a single-hole double-layer tunnel crossing a road according to claim 1, characterized in that, The construction measures formulated based on the aforementioned location relationship include: Based on the aforementioned location relationships, and considering road safety, the aforementioned construction measures were formulated. Construction simulation was conducted using finite element analysis to obtain the deformation characteristics of a single-hole double-layer tunnel crossing a road under the aforementioned construction measures. If the deformation pattern satisfies road safety requirements, then the construction measures are determined. If the deformation pattern does not meet road safety requirements, the construction measures shall be adjusted until road safety is met, and then the construction measures shall be determined.

4. The deformation dynamic control method for a single-hole double-layer tunnel crossing a road according to claim 3, characterized in that, Construction simulation was conducted using finite element analysis to obtain the deformation characteristics of a single-hole double-layer tunnel crossing a road under the aforementioned construction measures, including: A three-dimensional construction model was established using finite element analysis software. The three-dimensional construction model includes soil, working shaft, receiving shaft, and tunnel. Based on the aforementioned construction measures, a construction simulation was performed on the three-dimensional construction model, and the surface deformation patterns during the simulation process were recorded.

5. The deformation dynamic control method for a single-hole double-layer tunnel crossing a road according to claim 1, characterized in that, Real-time early warnings are issued for road dynamic deformation during the first and second stages of construction using the first deformation control early warning threshold and the second deformation control early warning threshold, respectively. Adjustments to the construction measures based on the early warning results include: During the first phase of construction, the measured value of dynamic deformation of the first road is monitored in real time. If the measured value of dynamic deformation of the first road reaches the first deformation control warning threshold, construction is stopped immediately and the corresponding construction measures are adjusted. If the measured value of dynamic deformation of the first road does not reach the first deformation control warning threshold by the end of the first phase of construction, the second phase of construction begins. During the second phase of construction, the measured value of dynamic deformation of the second road is monitored in real time. If the measured value of dynamic deformation of the second road reaches the second deformation control warning threshold, construction is stopped immediately and the corresponding construction measures are adjusted. If the measured value of dynamic deformation of the second road does not reach the second deformation control warning threshold by the end of the second phase of construction, the construction is completed.

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