Tunnel freezing and thawing cycle excavation operation method and device, storage medium and electronic equipment

Abstract

The invention relates to a tunnel freezing and thawing cycle excavation operation method and device, a storage medium and electronic equipment. The tunnel freezing and thawing cycle excavation operation method comprises the steps that the geomechanical environment where tunnel surrounding rock is located is evaluated, and heat damage characteristics of the tunnel surrounding rock and environmental factors influencing the heat damage characteristics are obtained; according to the heat damage characteristics of the tunnel surrounding rock and the environmental factors influencing the heat damage characteristics, a freeze-thaw cycle strategy is determined; wherein the freezing and thawing cycle strategy at least comprises arrangement of drill holes, freezing and thawing temperature of tunnel surrounding rock and freezing and thawing cycle times; according to the tunnel environment temperature and the degradation condition of the surrounding rock, the freezing and thawing cycle strategy is adjusted, and when the tunnel environment temperature and the degradation state of the surrounding rock reach the preset state, tunnel surrounding rock excavation operation is conducted, so that the tunnel construction environment is improved, and the tunnel construction difficulty degree is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of civil engineering technology, and in particular to a tunnel freeze-thaw cycle excavation operation method, a tunnel freeze-thaw cycle excavation operation device, a storage medium and an electronic device. Background Art

[0002] With the development of national economy and technology, many water conservancy, hydropower, railway and highway tunnels or tunnel projects have been developed in depth, and a large number of projects with a depth of more than one kilometer have emerged. In the construction of these projects, high geothermal heat damage is inevitable. The coupling of high geothermal and other factors aggravates the deformation and damage of tunnel surrounding rocks, increases the risk of excavation, and causes great difficulties for the construction and operation of underground projects. Summary of the invention

[0003] In view of this, the embodiments of the present disclosure are intended to provide a tunnel freeze-thaw cycle excavation operation method, a tunnel freeze-thaw cycle excavation operation device, a storage medium and an electronic device.

[0004] The technical solution of the present disclosure is achieved as follows:

[0005] In a first aspect, the present disclosure provides a tunnel freeze-thaw cycle excavation operation method.

[0006] The freeze-thaw cycle excavation method for a tunnel provided by the embodiment of the present disclosure includes:

[0007] Evaluate the geomechanical environment of the tunnel surrounding rock to obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics;

[0008] Determine a freeze-thaw cycle strategy based on the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freeze-thaw temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles;

[0009] The freeze-thaw cycle strategy is adjusted according to the tunnel environment temperature and the deterioration of the surrounding rock, and the tunnel surrounding rock excavation operation is carried out when the tunnel environment temperature and the deterioration state of the surrounding rock reach a predetermined state.

[0010] In some embodiments, the freeze-thaw cycle strategy is determined according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics, including:

[0011] By testing the thermal physical properties of the tunnel surrounding rock, the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock are obtained;

[0012] The freeze-thaw coefficient Kf and freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested through freeze-thaw tests;

[0013] Based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf, analyzing the rock degradation cycle of the tunnel surrounding rock, and determining the number of freeze-thaw cycles of the tunnel surrounding rock;

[0014] Determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT;

[0015] The layout positions of the drilling holes are determined according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock.

[0016] In some embodiments, analyzing the rock degradation cycle of the tunnel surrounding rock based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf to determine the number of freeze-thaw cycles of the tunnel surrounding rock includes:

[0017] According to the thermal expansion coefficient α and freeze-thaw coefficient Kf of the tunnel surrounding rock, the deformation and fracture mechanism of the tunnel surrounding rock is studied, the influence of a single hot and cold cycle on the tunnel surrounding rock is analyzed, and the deterioration and damage of the surrounding rock of the tunnel surrounding rock caused by a single hot and cold cycle is determined;

[0018] The number of freeze-thaw cycles of the tunnel surrounding rock is determined based on the freeze-thaw coefficient Kf of the tunnel surrounding rock and the deterioration and damage of the tunnel surrounding rock caused by a single cold and hot cycle.

[0019] In some embodiments, the step of obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes:

[0020] The geothermal anomaly section is analyzed through the borehole temperature data, and the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock; among which, the thermal damage characteristics of the tunnel surrounding rock include the geothermal anomaly section;

[0021] By investigating the geological structure, fault development, and groundwater seepage in the project area, the environmental factors and locations that affect the characteristics of heat damage are analyzed; the environmental factors that affect the characteristics of heat damage include at least one of the regional geological structure, fault development, and groundwater seepage.

[0022] In some embodiments, determining the layout position of the drilling arrangement according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock includes:

[0023] Drill more holes at locations where geothermal anomalies are controlled, and arrange holes at the tunnel face in a uniform distribution method;

[0024] The borehole spacing is calculated based on the thermal conductivity K of the tunnel surrounding rock so that interaction can occur between the two boreholes, allowing the freezing temperature and the melting temperature to be uniformly radiated on the tunnel face.

[0025] In some embodiments, the step of testing the thermal physical properties of the tunnel surrounding rock to obtain the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock includes:

[0026]

[0027] Where K is the thermal conductivity of the tunnel surrounding rock, Q is the heat flow, L is the length or thickness of the rock used in the experiment (m), and A is the area of ​​the rock used in the experiment (m 2 ), T2-T1 is the temperature gradient difference; T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature;

[0028]

[0029] Among them, α(T) is the expansion coefficient of the sample, L0 is the initial length of the rock used in the experiment (mm), and dL(T) is the length change of the rock used in the experiment in the temperature range dT (mm).

[0030] In some embodiments, the freeze-thaw coefficient Kf and the freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested by freeze-thaw test, including:

[0031]

[0032] Among them, K f is the freeze-thaw coefficient of rock, is the average value of saturated uniaxial compressive strength after freeze-thaw test (MPa), is the average value of saturated uniaxial compressive strength before freeze-thaw test (MPa);

[0033] ΔT = T2 - T1;

[0034] Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

[0035] In a second aspect, the present disclosure provides a tunnel freeze-thaw cycle excavation operation device, comprising:

[0036] Information acquisition module, used to evaluate the geomechanical environment of the tunnel surrounding rock, obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics;

[0037] A freeze-thaw cycle strategy determination module is used to determine the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freeze-thaw temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles;

[0038] The excavation operation module is used to adjust the freeze-thaw cycle strategy according to the tunnel environment temperature and the degradation of the surrounding rock, and to perform tunnel surrounding rock excavation operations when the tunnel environment temperature and the degradation state of the surrounding rock reach a predetermined state.

[0039] In a third aspect, the present disclosure provides a computer-readable storage medium on which a tunnel freeze-thaw cycle excavation operation program is stored. When the tunnel freeze-thaw cycle excavation operation program is executed by a processor, the tunnel freeze-thaw cycle excavation operation method described in the first aspect is implemented.

[0040] In a fourth aspect, the present disclosure provides an electronic device comprising a memory, a processor, and a tunnel freeze-thaw cycle excavation operation program stored in the memory and executable on the processor, wherein when the processor executes the tunnel freeze-thaw cycle excavation operation program, the tunnel freeze-thaw cycle excavation operation method described in the first aspect is implemented.

[0041] According to the freeze-thaw cycle excavation operation method of the tunnel embodiment of the present disclosure, the method includes evaluating the geomechanical environment in which the tunnel surrounding rock is located, obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; determining the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the temperature of the tunnel surrounding rock freezing and thawing, and the number of freeze-thaw cycles; adjusting the freeze-thaw cycle strategy according to the tunnel ambient temperature and the degradation of the surrounding rock, and performing tunnel surrounding rock excavation operations when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state. In the present application, by evaluating the geomechanical environment in which the tunnel surrounding rock is located, obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics, determining the freeze-thaw cycle strategy, adjusting the freeze-thaw cycle strategy according to the tunnel ambient temperature and the degradation state of the surrounding rock, and performing tunnel surrounding rock excavation operations when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state, it is beneficial to improve the tunnel construction environment and reduce the difficulty of tunnel construction.

[0042] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a flow chart of a tunnel freeze-thaw cycle excavation method according to an exemplary embodiment;

[0044] Figure 2 is a schematic diagram of drilling arrangement according to an exemplary embodiment;

[0045] Figure 3a is a schematic diagram showing the tunnel damage and crack penetration in the initial freeze-thaw cycle according to an exemplary embodiment;

[0046] Figure 3b is a schematic diagram showing the tunnel damage and crack penetration in the final freeze-thaw cycle according to an exemplary embodiment;

[0047] Figure 4 It is a schematic structural diagram of a tunnel freeze-thaw cycle excavation operation device according to an exemplary embodiment. DETAILED DESCRIPTION

[0048] Embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be construed as limiting the present disclosure.

[0049] With the development of national economy and technology, many water conservancy, hydropower, railway and highway tunnels or tunnel projects have been developed in depth, and a large number of projects with a depth of more than one kilometer have emerged. In the construction of these projects, high geothermal heat damage is inevitable. The coupling of high geothermal and other factors aggravates the deformation and damage of tunnel surrounding rocks, increases the risk of excavation, and causes great difficulties for the construction and operation of underground projects.

[0050] In view of the above situation, the present invention provides a tunnel freeze-thaw cycle excavation operation method. Figure 1 FIG. 1 is a flow chart of a tunnel freeze-thaw cycle excavation method according to an exemplary embodiment. Figure 1 As shown, the freeze-thaw cycle excavation method of the tunnel includes:

[0051] Step 10: Evaluate the geomechanical environment of the tunnel surrounding rock to obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics;

[0052] Step 11: Determine a freeze-thaw cycle strategy based on the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freeze-thaw temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles;

[0053] Step 12: adjusting the freeze-thaw cycle strategy according to the tunnel environment temperature and the degradation of the surrounding rock, and performing tunnel surrounding rock excavation when the tunnel environment temperature and the degradation of the surrounding rock reach a predetermined state.

[0054] In this exemplary embodiment, the step of obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes:

[0055] Surrounding rock temperature measurement: First, the geothermal thermal anomaly section is analyzed through the borehole temperature data. Then, the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock. 28°C is used as the limiting temperature value for evaluating thermal damage. Among them, the thermal damage characteristics of the tunnel surrounding rock include the geothermal thermal anomaly section.

[0056] Investigation of high geothermal control factors: Investigate the geological structure, fault development, groundwater seepage, etc. in the project area, analyze the main control factors and positions of geothermal temperature; Environmental factors that affect the characteristics of heat damage, including regional geological structure, fault development, groundwater seepage, etc.

[0057] In this exemplary embodiment, the freeze-thaw cycle strategy is adjusted according to the tunnel environmental temperature and the degradation of the surrounding rock, including: adjusting the layout of boreholes, the freeze-thaw temperature of the tunnel surrounding rock and the number of freeze-thaw cycles according to the tunnel environmental temperature and the degradation of the surrounding rock, so that the tunnel environmental temperature and the degradation state of the surrounding rock reach a predetermined state, thereby reducing the difficulty of tunnel excavation.

[0058] According to the freeze-thaw cycle excavation operation method of the tunnel embodiment of the present disclosure, the method includes evaluating the geomechanical environment in which the tunnel surrounding rock is located, obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; determining the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the temperature of the tunnel surrounding rock freezing and thawing, and the number of freeze-thaw cycles; adjusting the freeze-thaw cycle strategy according to the tunnel ambient temperature and the degradation of the surrounding rock, and performing tunnel surrounding rock excavation operations when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state. In the present application, by evaluating the geomechanical environment in which the tunnel surrounding rock is located, obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics, determining the freeze-thaw cycle strategy, adjusting the freeze-thaw cycle strategy according to the tunnel ambient temperature and the degradation state of the surrounding rock, and performing tunnel surrounding rock excavation operations when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state, it is beneficial to improve the tunnel construction environment and reduce the difficulty of tunnel construction.

[0059] In some embodiments, the freeze-thaw cycle strategy is determined according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics, including:

[0060] By testing the thermal physical properties of the tunnel surrounding rock, the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock are obtained;

[0061] The freeze-thaw coefficient Kf and freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested through freeze-thaw tests;

[0062] Based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf, analyzing the rock degradation cycle of the tunnel surrounding rock, and determining the number of freeze-thaw cycles of the tunnel surrounding rock;

[0063] Determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT;

[0064] The layout positions of the drilling holes are determined according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock.

[0065] In this exemplary embodiment, analyzing the rock degradation cycle of the tunnel surrounding rock based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf to determine the number of freeze-thaw cycles of the tunnel surrounding rock includes:

[0066] According to the thermal expansion coefficient α and freeze-thaw coefficient Kf of the tunnel surrounding rock, the deformation and fracture mechanism of the tunnel surrounding rock is studied, the influence of a single hot and cold cycle on the tunnel surrounding rock is analyzed, and the deterioration and damage of the surrounding rock of the tunnel surrounding rock caused by a single hot and cold cycle is determined;

[0067] The number of freeze-thaw cycles of the tunnel surrounding rock is determined based on the freeze-thaw coefficient Kf of the tunnel surrounding rock and the deterioration and damage of the tunnel surrounding rock caused by a single cold and hot cycle.

[0068] In this exemplary embodiment, the freeze-thaw coefficient Kf of the tunnel surrounding rock changes and is updated every time the tunnel surrounding rock is frozen and thawed. After N times of freezing and thawing, the freeze-thaw coefficient Kf of the tunnel surrounding rock remains unchanged. The number of freeze-thaw cycles N obtained at this time is the number of freeze-thaw cycles that need to be performed on the tunnel surrounding rock before tunnel excavation.

[0069] In this exemplary embodiment, the rock degradation cycle is analyzed according to the freeze-thaw coefficient Kf obtained above, and the number of freeze-thaw cycles of the surrounding rock on site is calculated;

[0070] The freeze-thaw cycle is set according to the optimal time of the rock freeze-thaw cycle in indoor experiments. Generally, one freeze-thaw cycle is set to 12 hours, and the freezing and melting time are set to 6 hours respectively.

[0071] In some embodiments, determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT comprises:

[0072] ΔT = T2 - T1;

[0073] Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

[0074] In this exemplary embodiment, the measured temperature T2 of the surrounding rock is determined to be the melting temperature of the surrounding rock.

[0075] In some embodiments, the step of obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes:

[0076] The geothermal anomaly section is analyzed through the borehole temperature data, and the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock; among which, the thermal damage characteristics of the tunnel surrounding rock include the geothermal anomaly section;

[0077] By investigating the geological structure, fault development, and groundwater seepage in the project area, the environmental factors and locations that affect the characteristics of heat damage are analyzed; the environmental factors that affect the characteristics of heat damage include at least one of the regional geological structure, fault development, and groundwater seepage.

[0078] In this exemplary embodiment, during the construction process, the engineering geothermal thermal anomaly section is first analyzed through the drilling temperature data, and then the temperature of the face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock, with 28°C as the limiting temperature value for assessing heat damage problems; the geological structure, fault development, groundwater seepage, etc. in the geothermal thermal anomaly area are investigated. For high geothermal phenomena caused by hot dry rocks, a freeze-thaw cycle method is required for construction operations. For high geothermal phenomena caused by groundwater or hot springs, a freezing method is required to control the flow of groundwater, relying on the temperature of the groundwater itself for circulation and melting.

[0079] In some embodiments, determining the layout position of the drilling arrangement according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock includes:

[0080] Drill more holes at locations where geothermal anomalies are controlled, and arrange holes at the tunnel face in a uniform distribution method;

[0081] The borehole spacing is calculated based on the thermal conductivity K of the tunnel surrounding rock so that interaction can occur between the two boreholes, allowing the freezing temperature and the melting temperature to be uniformly radiated on the tunnel face.

[0082] In this exemplary embodiment, Figure 2 FIG. 1 is a schematic diagram of drilling arrangement according to an exemplary embodiment. Figure 2 As shown in the figure, firstly, the drilling process is carried out at the location of the geothermal anomaly control factor, and the drilling arrangement is carried out at the rest of the tunnel face according to the uniform distribution method. The drilling spacing is calculated according to the rock thermal conductivity K to ensure that the two boreholes can interact with each other and ensure that the freezing temperature and melting temperature can be evenly radiated on the tunnel face. Among them, the drilling arrangement depth can be 2m, the drilling hole diameter can be 75mm, and it is generated at one time using a pneumatic down-the-hole hammer drill.

[0083] In some embodiments, the step of testing the thermal physical properties of the tunnel surrounding rock to obtain the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock includes:

[0084]

[0085] Where K is the thermal conductivity of the tunnel surrounding rock, Q is the heat flow, L is the length or thickness of the rock used in the experiment (m), and A is the area of ​​the rock used in the experiment (m 2 ), T2-T1 is the temperature gradient difference; T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature;

[0086]

[0087] Among them, α(T) is the expansion coefficient of the sample, L0 is the initial length of the rock used in the experiment (mm), and dL(T) is the length change of the rock used in the experiment in the temperature range dT (mm).

[0088] In this exemplary embodiment, the freeze-thaw coefficient Kf and the freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested by freeze-thaw test, including:

[0089]

[0090] Among them, K f is the freeze-thaw coefficient of rock, is the average value of saturated uniaxial compressive strength after freeze-thaw test (MPa), is the average value of saturated uniaxial compressive strength before freeze-thaw test (MPa);

[0091] ΔT = T2 - T1;

[0092] Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

[0093] In this exemplary embodiment, the freeze-thaw test is a repeated freezing and thawing process. After reaching a certain number of times, the physical properties of the rock itself, including strength parameters and elastic parameters, will remain unchanged, that is, Kf remains unchanged, and the number of freeze-thaw cycles can be obtained at this time.

[0094] In this exemplary embodiment, Figure 3a is a schematic diagram showing the tunnel damage and crack penetration in the initial freeze-thaw cycle according to an exemplary embodiment; Figure 3b FIG. 1 is a schematic diagram showing the tunnel damage and crack penetration in the final freeze-thaw cycle according to an exemplary embodiment. Figure 3a , 3bAs shown in the figure, after multiple freeze-thaw cycles from the initial freeze-thaw cycle to the final freeze-thaw cycle, the development degree of the surrounding rock cracks can be judged by observing the changes in the cracks around the boreholes and between the holes. Secondly, the electrical measurement method is used to measure the changes in the resistivity between the holes to judge the deterioration of the surrounding rock. When the resistivity remains unchanged and the value is low, the operation can be stopped.

[0095] In this exemplary embodiment, the temperature of the surrounding rock in the hole and the surface temperature of the rock wall and the face are measured, and the ambient temperature in the cave is measured to evaluate the cooling effect.

[0096] In this exemplary embodiment, the groundwater seepage is observed, and its flow rate and water temperature are measured, and compared with before the freeze-thaw cycle operation, the plugging effect can be evaluated.

[0097] In the present application, the surrounding rock and groundwater are frozen to control the high temperature heat damage and groundwater inrush phenomenon, which is beneficial to reduce the impact of high temperature heat damage on personnel operations.

[0098] In the present application, the freeze-thaw cycle method is beneficial to deteriorate the surrounding rock parameters, so that the surrounding rock can achieve the purpose of breaking the rock or reducing the difficulty of excavation by utilizing the degradation of rock parameters during multiple freeze-thaw cycles.

[0099] The present invention discloses a tunnel freeze-thaw cycle excavation operation device. Figure 4 FIG. 1 is a schematic diagram of a tunnel freeze-thaw cycle excavation device according to an exemplary embodiment. Figure 4 As shown, the tunnel freeze-thaw cycle excavation operation device includes:

[0100] The information acquisition module 40 is used to evaluate the geomechanical environment of the tunnel surrounding rock, obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics;

[0101] A freeze-thaw cycle strategy determination module 41 is used to determine a freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freezing and thawing temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles;

[0102] The excavation operation module 42 is used to adjust the freeze-thaw cycle strategy according to the tunnel environment temperature and the degradation of the surrounding rock, and perform tunnel surrounding rock excavation operations when the tunnel environment temperature and the degradation state of the surrounding rock reach a predetermined state.

[0103] In this exemplary embodiment, the step of obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes:

[0104] Surrounding rock temperature measurement: First, the geothermal thermal anomaly section is analyzed through the borehole temperature data. Then, the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock. 28°C is used as the limiting temperature value for evaluating thermal damage. Among them, the thermal damage characteristics of the tunnel surrounding rock include the geothermal thermal anomaly section.

[0105] Investigation of high geothermal control factors: Investigate the geological structure, fault development, groundwater seepage, etc. in the project area, analyze the main control factors and positions of geothermal temperature; Environmental factors that affect the characteristics of heat damage, including regional geological structure, fault development, groundwater seepage, etc.

[0106] In this exemplary embodiment, the freeze-thaw cycle strategy is adjusted according to the tunnel environmental temperature and the degradation of the surrounding rock, including: adjusting the layout of boreholes, the freeze-thaw temperature of the tunnel surrounding rock and the number of freeze-thaw cycles according to the tunnel environmental temperature and the degradation of the surrounding rock, so that the tunnel environmental temperature and the degradation state of the surrounding rock reach a predetermined state, thereby reducing the difficulty of tunnel excavation.

[0107] According to the tunnel freeze-thaw cycle excavation operation device of the embodiment of the present disclosure, it is used to evaluate the geomechanical environment in which the tunnel surrounding rock is located, obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; determine the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the temperature of the tunnel surrounding rock freezing and thawing, and the number of freeze-thaw cycles; according to the tunnel ambient temperature and the degradation of the surrounding rock, the freeze-thaw cycle strategy is adjusted, and when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state, the tunnel surrounding rock excavation operation is performed. In the present application, by evaluating the geomechanical environment in which the tunnel surrounding rock is located, obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics, determining the freeze-thaw cycle strategy, and adjusting the freeze-thaw cycle strategy according to the tunnel ambient temperature and the degradation state of the surrounding rock, and when the tunnel ambient temperature and the degradation state of the surrounding rock reach a predetermined state, the tunnel surrounding rock excavation operation is performed, which is conducive to improving the tunnel construction environment and reducing the difficulty of tunnel construction.

[0108] In some embodiments, the freeze-thaw cycle strategy determination module 41 is used to

[0109] By testing the thermal physical properties of the tunnel surrounding rock, the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock are obtained;

[0110] The freeze-thaw coefficient Kf and freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested through freeze-thaw tests;

[0111] Based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf, analyzing the rock degradation cycle of the tunnel surrounding rock, and determining the number of freeze-thaw cycles of the tunnel surrounding rock;

[0112] Determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT;

[0113] The layout positions of the drilling holes are determined according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock.

[0114] In this exemplary embodiment, analyzing the rock degradation cycle of the tunnel surrounding rock based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf to determine the number of freeze-thaw cycles of the tunnel surrounding rock includes:

[0115] According to the thermal expansion coefficient α and freeze-thaw coefficient Kf of the tunnel surrounding rock, the deformation and fracture mechanism of the tunnel surrounding rock is studied, the influence of a single hot and cold cycle on the tunnel surrounding rock is analyzed, and the deterioration and damage of the surrounding rock of the tunnel surrounding rock caused by a single hot and cold cycle is determined;

[0116] The number of freeze-thaw cycles of the tunnel surrounding rock is determined based on the freeze-thaw coefficient Kf of the tunnel surrounding rock and the deterioration and damage of the tunnel surrounding rock caused by a single cold and hot cycle.

[0117] In this exemplary embodiment, the freeze-thaw coefficient Kf of the tunnel surrounding rock changes and is updated every time the tunnel surrounding rock is frozen and thawed. After N times of freezing and thawing, the freeze-thaw coefficient Kf of the tunnel surrounding rock remains unchanged. The number of freeze-thaw cycles N obtained at this time is the number of freeze-thaw cycles that need to be performed on the tunnel surrounding rock before tunnel excavation.

[0118] In this exemplary embodiment, the rock degradation cycle is analyzed according to the freeze-thaw coefficient Kf obtained above, and the number of freeze-thaw cycles of the surrounding rock on site is calculated;

[0119] The freeze-thaw cycle is set according to the optimal time of the rock freeze-thaw cycle in indoor experiments. Generally, one freeze-thaw cycle is set to 12 hours, and the freezing and melting time are set to 6 hours respectively.

[0120] In some embodiments, determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT comprises:

[0121] ΔT = T2 - T1;

[0122] Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

[0123] In this exemplary embodiment, the measured temperature T2 of the surrounding rock is determined to be the melting temperature of the surrounding rock.

[0124] In some embodiments, the information acquisition module 40 is used to

[0125] The geothermal anomaly section is analyzed through the borehole temperature data, and the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock; among which, the thermal damage characteristics of the tunnel surrounding rock include the geothermal anomaly section;

[0126] By investigating the geological structure, fault development, and groundwater seepage in the project area, the environmental factors and locations that affect the characteristics of heat damage are analyzed; the environmental factors that affect the characteristics of heat damage include at least one of the regional geological structure, fault development, and groundwater seepage.

[0127] In this exemplary embodiment, during the construction process, the engineering geothermal thermal anomaly section is first analyzed through the drilling temperature data, and then the temperature of the face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock, with 28°C as the limiting temperature value for assessing heat damage problems; the geological structure, fault development, groundwater seepage, etc. in the geothermal thermal anomaly area are investigated. For high geothermal phenomena caused by hot dry rocks, a freeze-thaw cycle method is required for construction operations. For high geothermal phenomena caused by groundwater or hot springs, a freezing method is required to control the flow of groundwater, relying on the temperature of the groundwater itself for circulation and melting.

[0128] In some embodiments, determining the layout position of the drilling arrangement according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock includes:

[0129] Drill more holes at locations where geothermal anomalies are controlled, and arrange holes at the tunnel face in a uniform distribution method;

[0130] The borehole spacing is calculated based on the thermal conductivity K of the tunnel surrounding rock so that interaction can occur between the two boreholes, allowing the freezing temperature and the melting temperature to be uniformly radiated on the tunnel face.

[0131] In this exemplary embodiment, Figure 2 FIG. 1 is a schematic diagram of drilling arrangement according to an exemplary embodiment. Figure 2 As shown in the figure, firstly, the drilling process is carried out at the location of the geothermal anomaly control factor, and the drilling arrangement is carried out at the rest of the tunnel face according to the uniform distribution method. The drilling spacing is calculated according to the rock thermal conductivity K to ensure that the two boreholes can interact with each other and ensure that the freezing temperature and melting temperature can be evenly radiated on the tunnel face. Among them, the drilling arrangement depth can be 2m, the drilling hole diameter can be 75mm, and it is generated at one time using a pneumatic down-the-hole hammer drill.

[0132] In some embodiments, the step of testing the thermal physical properties of the tunnel surrounding rock to obtain the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock includes:

[0133]

[0134] Where K is the thermal conductivity of the tunnel surrounding rock, Q is the heat flow, L is the length or thickness of the rock used in the experiment (m), and A is the area of ​​the rock used in the experiment (m 2 ), T2-T1 is the temperature gradient difference; T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature;

[0135]

[0136] Among them, α(T) is the expansion coefficient of the sample, L0 is the initial length of the rock used in the experiment (mm), and dL(T) is the length change of the rock used in the experiment in the temperature range dT (mm).

[0137] In this exemplary embodiment, the freeze-thaw coefficient Kf and the freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested by freeze-thaw test, including:

[0138]

[0139] Among them, K f is the freeze-thaw coefficient of rock, is the average value of saturated uniaxial compressive strength after freeze-thaw test (MPa), is the average value of saturated uniaxial compressive strength before freeze-thaw test (MPa);

[0140] ΔT = T2 - T1;

[0141] Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

[0142] In this exemplary embodiment, the freeze-thaw test is a repeated freezing and thawing process. After reaching a certain number of times, the physical properties of the rock itself, including strength parameters and elastic parameters, will remain unchanged, that is, Kf remains unchanged, and the number of freeze-thaw cycles can be obtained at this time.

[0143] In this exemplary embodiment, Figure 3a , 3b As shown in the figure, after multiple freeze-thaw cycles from the initial freeze-thaw cycle to the final freeze-thaw cycle, the development degree of the surrounding rock cracks can be judged by observing the changes in the cracks around the boreholes and between the holes. Secondly, the electrical measurement method is used to measure the changes in the resistivity between the holes to judge the deterioration of the surrounding rock. When the resistivity remains unchanged and the value is low, the operation can be stopped.

[0144] In this exemplary embodiment, the temperature of the surrounding rock in the hole and the surface temperature of the rock wall and the face are measured, and the ambient temperature in the cave is measured to evaluate the cooling effect.

[0145] In this exemplary embodiment, the groundwater seepage is observed, and its flow rate and water temperature are measured, and compared with before the freeze-thaw cycle operation, the plugging effect can be evaluated.

[0146] In the present application, the surrounding rock and groundwater are frozen to control the high temperature heat damage and groundwater inrush phenomenon, which is beneficial to reduce the impact of high temperature heat damage on personnel operations.

[0147] In the present application, the freeze-thaw cycle method is beneficial to deteriorate the surrounding rock parameters, so that the surrounding rock can achieve the purpose of breaking the rock or reducing the difficulty of excavation by utilizing the degradation of rock parameters during multiple freeze-thaw cycles.

[0148] The present disclosure provides a computer-readable storage medium on which a tunnel freeze-thaw cycle excavation operation program is stored. When the tunnel freeze-thaw cycle excavation operation program is executed by a processor, the tunnel freeze-thaw cycle excavation operation method described in the above embodiments is implemented.

[0149] The present disclosure provides an electronic device, including a memory, a processor, and a tunnel freeze-thaw cycle excavation operation program stored in the memory and executable on the processor. When the processor executes the tunnel freeze-thaw cycle excavation operation program, the tunnel freeze-thaw cycle excavation operation method described in the above embodiments is implemented.

[0150] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented 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 combination with these 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 combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (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 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 and then editing, interpreting or otherwise processing in a suitable manner if necessary, and then stored in a computer memory.

[0151] It should be understood that the various parts of the present disclosure can be implemented in hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: 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.

[0152] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0153] In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0154] In addition, the terms "first", "second", etc. used in the embodiments of the present disclosure are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the embodiments. Therefore, the features defined by the terms "first", "second", etc. in the embodiments of the present disclosure may explicitly or implicitly indicate that at least one of the features is included in the embodiment. In the description of the present disclosure, the word "multiple" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0155] In the present disclosure, unless otherwise clearly specified or limited in the embodiments, the terms "installed", "connected", "connected" and "fixed" etc. appearing in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integrated connection. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements, or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to the specific implementation situation.

[0156] In the present disclosure, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0157] Although the embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present disclosure. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present disclosure.

Claims

1. A tunnel freeze-thaw cycle excavation method, characterized in that: include: Evaluate the geomechanical environment of the tunnel surrounding rock to obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; Determine a freeze-thaw cycle strategy based on the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freeze-thaw temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles; The freeze-thaw cycle strategy is adjusted according to the tunnel environment temperature and the deterioration of the surrounding rock, and the tunnel surrounding rock excavation operation is carried out when the tunnel environment temperature and the deterioration state of the surrounding rock reach a predetermined state.

2. The freeze-thaw cycle tunnel excavation method according to claim 1, characterized in that: Determining the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes: By testing the thermal physical properties of the tunnel surrounding rock, the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock are obtained; The freeze-thaw coefficient Kf and freeze-thaw temperature range ΔT of the tunnel surrounding rock are tested through freeze-thaw tests; Based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf, analyzing the rock degradation cycle of the tunnel surrounding rock, and determining the number of freeze-thaw cycles of the tunnel surrounding rock; Determining the freezing temperature and the melting temperature according to the freeze-thaw temperature range ΔT; The layout positions of the drilling holes are determined according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock.

3. The freeze-thaw cycle tunnel excavation method according to claim 2, characterized in that: The step of analyzing the rock degradation cycle of the tunnel surrounding rock based on the thermal expansion coefficient α and the freeze-thaw coefficient Kf to determine the number of freeze-thaw cycles of the tunnel surrounding rock includes: According to the thermal expansion coefficient α and freeze-thaw coefficient Kf of the tunnel surrounding rock, the deformation and fracture mechanism of the tunnel surrounding rock is studied, the influence of a single hot and cold cycle on the tunnel surrounding rock is analyzed, and the deterioration and damage of the surrounding rock of the tunnel surrounding rock caused by a single hot and cold cycle is determined; The number of freeze-thaw cycles of the tunnel surrounding rock is determined based on the freeze-thaw coefficient Kf of the tunnel surrounding rock and the deterioration and damage of the tunnel surrounding rock caused by a single cold and hot cycle.

4. The freeze-thaw cycle tunnel excavation method according to claim 1, characterized in that: The step of obtaining the thermal damage characteristics of the tunnel surrounding rock and the environmental factors affecting the thermal damage characteristics includes: The geothermal anomaly section is analyzed through the borehole temperature data, and the temperature of the tunnel face and rock wall is measured in the thermal anomaly section to analyze the temperature level of the surrounding rock; among them, the thermal damage characteristics of the tunnel surrounding rock include the geothermal anomaly section; By investigating the geological structure, fault development, and groundwater seepage in the project area, the environmental factors and locations that affect the characteristics of heat damage are analyzed; the environmental factors that affect the characteristics of heat damage include at least one of the regional geological structure, fault development, and groundwater seepage.

5. The freeze-thaw cycle tunnel excavation method according to claim 2, characterized in that: The method of determining the layout position of the drilling holes according to the geomechanical environment of the tunnel surrounding rock and the thermal conductivity K of the tunnel surrounding rock comprises: Drill more holes at locations where geothermal anomalies are controlled, and arrange holes at the tunnel face in a uniform distribution method; The borehole spacing is calculated based on the thermal conductivity K of the tunnel surrounding rock so that interaction can occur between the two boreholes, allowing the freezing temperature and the melting temperature to be uniformly radiated on the tunnel face.

6. The freeze-thaw cycle tunnel excavation method according to claim 2, characterized in that: The thermal physical property test of the tunnel surrounding rock is performed to obtain the thermal conductivity K and thermal expansion coefficient α of the tunnel surrounding rock, including: Where K is the thermal conductivity of the tunnel surrounding rock, Q is the heat flow, L is the length or thickness of the rock used in the experiment (m), and A is the area of ​​the rock used in the experiment (m 2 ), T2-T1 is the temperature gradient difference; T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; Among them, α(T) is the expansion coefficient of the sample, L0 is the initial length of the rock used in the experiment (mm), and dL(T) is the length change of the rock used in the experiment in the temperature range dT (mm).

7. The freeze-thaw cycle tunnel excavation method according to claim 2, characterized in that: The freeze-thaw test is used to test the freeze-thaw coefficient Kf and the freeze-thaw temperature range ΔT of the tunnel surrounding rock, including: Among them, K f is the freeze-thaw coefficient of rock, is the average value of saturated uniaxial compressive strength after freeze-thaw test (MPa), is the average value of saturated uniaxial compressive strength before freeze-thaw test (MPa); ΔT = T2 - T1; Among them, ΔT is the freeze-thaw temperature range, T2 is the measured temperature of the surrounding rock, and T1 is the freezing temperature; among them, the freezing temperature is the temperature value corresponding to the rock degradation condition remaining unchanged as the temperature decreases.

8. A tunnel freeze-thaw cycle excavation device, characterized in that: include: Information acquisition module, used to evaluate the geomechanical environment of the tunnel surrounding rock, obtain the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; A freeze-thaw cycle strategy determination module is used to determine the freeze-thaw cycle strategy according to the thermal damage characteristics of the tunnel surrounding rock and the environmental factors that affect the thermal damage characteristics; wherein the freeze-thaw cycle strategy at least includes the layout of the boreholes, the freeze-thaw temperature of the tunnel surrounding rock, and the number of freeze-thaw cycles; The excavation operation module is used to adjust the freeze-thaw cycle strategy according to the tunnel environment temperature and the degradation of the surrounding rock, and to perform tunnel surrounding rock excavation operations when the tunnel environment temperature and the degradation state of the surrounding rock reach a predetermined state.

9. A computer-readable storage medium, characterized in that: A tunnel freeze-thaw cycle excavation operation program is stored thereon. When the tunnel freeze-thaw cycle excavation operation program is executed by the processor, the tunnel freeze-thaw cycle excavation operation method described in any one of claims 1 to 7 is implemented.

10. An electronic device, characterized in that: The invention comprises a memory, a processor and a tunnel freeze-thaw cycle excavation operation program stored in the memory and executable on the processor. When the processor executes the tunnel freeze-thaw cycle excavation operation program, the tunnel freeze-thaw cycle excavation operation method described in any one of claims 1 to 7 is implemented.

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