A tunnel multi-structure thermal-mechanical coupling test system

Abstract

The present application provides a tunnel multi-structure thermal coupling test system, which relates to the technical field of high-temperature tunnel structure testing. The system includes: a central control subsystem, which is used to obtain the target working condition of the lining to be tested to determine its target pressure value, target state information and target temperature, and send the target pressure value to the longitudinal loading subsystem, send the target state information to the sample fixing subsystem, and send the target temperature to the controllable heating subsystem, and the target state information includes the target angle and target height; the sample fixing subsystem is used to clamp the lining to be tested, and adjust the angle and height of the lining to be tested so that the target stress surface of the lining to be tested and the target stress point on the target stress surface are facing the longitudinal loading subsystem; the longitudinal loading subsystem is used to apply a loading pressure of the target pressure value to the target stress point of the lining to be tested in the longitudinal direction; the controllable heating subsystem is used to apply the target temperature to the lining to be tested. The present application can improve the accuracy and efficiency of the test.

Description

Technical Field

[0001] The present application relates to the technical field of high-temperature tunnel structure testing, and in particular to a tunnel multi-structure thermal-mechanical coupling testing system. Background Art

[0002] Tunnels are an important part of my country's transportation infrastructure. my country has always attached great importance to the development and research of tunnel technology. At present, my country's development in the field of tunnels has reached the international advanced level, and the total length of existing tunnels has exceeded 20,000 kilometers. However, with the increase in the number of tunnels, the frequency of tunnel fire accidents has also increased. Fire has multiple negative effects on the tunnel lining structure system. First, the fire will significantly reduce the mechanical properties of the various parts of the tunnel structure, thereby weakening its bearing capacity and may even cause the collapse of the structure. In addition, the tunnel lining structure system is different from the ground building. The permanent deformation caused by the fire will not only redistribute the internal force of the structural system, resulting in a decrease in its bearing capacity, but may also have adverse effects on the ground buildings and nearby structures. Therefore, it is particularly important to study the mechanical properties of the tunnel structure system under high temperature environment.

[0003] Due to the randomness of accidents and the complexity of underground structures, the forces on tunnel structures are also diverse. Integrity: when an accident occurs, in addition to the lining, which is the main force-bearing structure, the tunnel's beams, upper lane slabs, supporting columns and other structures may be subjected to heat and force; multi-directionality: there are many possibilities for the forces on the tunnel structures, not all of which are vertical forces, and even the internal forces on the lining during some accidents; complexity: due to the complex internal structure of the tunnel and the many factors that affect its internal load and heat transfer when an accident occurs, the load sharing of each structure is complex. However, most of the current devices for high-temperature mechanical properties test research on tunnel structures are uniaxial vertical loading of linings / segments, and a small number are multi-point loading. In addition, under the same fire environment, the performance degradation of other tunnel structures under fire is not considered. A comprehensive test system capable of conducting mechanical properties tests on various tunnel structures at high temperatures has not yet been reported. Summary of the invention

[0004] The present application provides a tunnel multi-structure thermal-mechanical coupling test system to solve the problem in the prior art of inaccurate detection of mechanical properties of tunnel structures under fire conditions due to different forces at different angles of the tunnel structure.

[0005] In a first aspect, the present application provides a tunnel multi-structure thermal-mechanical coupling test system, including a central control subsystem, a longitudinal loading subsystem, a sample fixing subsystem and a controllable temperature rise subsystem, wherein the central control subsystem is respectively connected in communication with the longitudinal loading subsystem, the sample fixing subsystem and the controllable temperature rise subsystem;

[0006] The central control subsystem is used to obtain the target working condition of the lining to be tested, determine the target pressure value, target state information and target temperature of the lining to be tested based on the target working condition, and send the target pressure value to the longitudinal loading subsystem, send the target state information to the sample fixing subsystem, and send the target temperature to the controllable temperature rising subsystem, wherein the target state information includes a target angle and a target height;

[0007] The sample fixing subsystem is used to clamp the lining to be tested, and adjust the angle and height of the lining to be tested according to the target state information, so that the target force-bearing surface of the lining to be tested and the target force-bearing point on the target force-bearing surface face the longitudinal loading subsystem;

[0008] The longitudinal loading subsystem is used to apply a loading pressure of the target pressure value to a target stress point on a target stress surface of the lining to be tested in the longitudinal direction;

[0009] The controllable temperature rise subsystem is used to apply the target temperature to the lining to be tested.

[0010] The present application provides a tunnel multi-structure thermal-mechanical coupling test system, which integrates multiple subsystems such as longitudinal loading, sample fixing and controllable heating through a central control subsystem, realizes a high degree of automation of the experimental process, simplifies the operation process, and improves the accuracy and efficiency of the test; then, the central control subsystem can accurately determine the target pressure value, target state information and target temperature according to the input target working condition and send them to the corresponding system, so that the system can more accurately simulate the stress state and temperature change of the tunnel lining in the actual working environment, thereby providing more reliable test data; in addition, the sample fixing subsystem can adjust the angle and height of the lining to be tested according to the target state information to ensure that the target stress surface and the target stress point thereon are facing the longitudinal loading subsystem. This flexibility and adaptability make the system applicable to tunnel lining tests of different types and sizes, greatly enhancing the versatility and practicality of the system; at the same time, by combining the longitudinal loading and controllable heating functions, the system can simultaneously simulate the coupling effect of the tunnel lining under stress and temperature change, which is helpful to more comprehensively evaluate the performance and safety of the tunnel lining, and provide strong technical support for the design and construction of tunnel engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0012] Figure 1 It is a structural schematic diagram of a tunnel multi-structure thermal-mechanical coupling test system provided in an embodiment of the present application;

[0013] Figure 2 is a structural schematic diagram of a self-reaction force frame provided in an embodiment of the present application;

[0014] Figure 3 is a structural schematic diagram of a longitudinal loading subsystem provided in an embodiment of the present application;

[0015] Figure 4 is a schematic structural diagram of a sample fixing subsystem provided in an embodiment of the present application;

[0016] Figure 5 is a structural schematic diagram of a first lining fixing subsystem provided in an embodiment of the present application;

[0017] Figure 6 It is a structural schematic diagram of a controllable temperature-raising subsystem provided in an embodiment of the present application;

[0018] Figure 7 It is a structural schematic diagram of a box-type heating device provided in an embodiment of the present application;

[0019] Figure 8 is a schematic diagram of the structure of a cooling subsystem provided in an embodiment of the present application;

[0020] Fig. 9 It is a structural schematic diagram of the micrometer and pressure sensor provided in the embodiment of the present application in the longitudinal loading subsystem. DETAILED DESCRIPTION

[0021] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0022] In order to make the purpose, technical solutions and advantages of the present application clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0023] Due to the different forces at different angles of the tunnel structure, the mechanical properties of each structure of the tunnel under the fire environment are inaccurately tested. This application provides a tunnel multi-structure thermal coupling test system. While having a complete tunnel lining thermal coupling test system, this application also has equipment for numerical simulation of tunnel fires, a device for loading each load-bearing part of the tunnel, and a complete automated process from sample placement to cooling equipment at the end of the test. Compared with the traditional lining test system, this application can load each surface, point, and angle of the lining, and can perform mechanical property tests and safety tests on the weak parts of each structure of the tunnel under the same working condition based on the disaster simulation results of the three-dimensional tunnel twin model. Better simulate the stress conditions of the tunnel lining structure under a complex underground environment; be able to apply a variety of load-temperature conditions to the tunnel structure, grasp the conditions of each structure of the tunnel, and have a more comprehensive understanding of the overall situation of the tunnel when an accident occurs; be able to realize the automation of the entire system from fixing the lining structure to cooling at the end of the test to eliminate errors, make the test results more accurate, make the test process safer, and reduce costs. And it can meet market demand and is worth promoting.

[0024] Specific tunnel multi-structure thermal-mechanical coupling test system reference Figure 1 , Figure 1 This is a schematic diagram of the structure of the tunnel multi-structure thermal coupling test system provided in the embodiment of the present application. Figure 1 As shown, the tunnel multi-structure thermal-mechanical coupling test system includes a central control subsystem 1, a longitudinal loading subsystem 2, a sample fixing subsystem 3 and a controllable temperature rise subsystem 4. The central control subsystem 1 is communicated with the longitudinal loading subsystem 2, the sample fixing subsystem 3 and the controllable temperature rise subsystem 4 respectively.

[0025] The central control subsystem 1 is used to obtain the target working condition of the lining to be tested, determine the target pressure value, target state information and target temperature of the lining to be tested based on the target working condition, and send the target pressure value to the longitudinal loading subsystem 2, send the target state information to the sample fixing subsystem 3, and send the target temperature to the controllable heating subsystem 4. The target state information includes the target angle and target height.

[0026] The sample fixing subsystem 3 is used to clamp the lining to be tested and adjust the angle and height of the lining to be tested according to the target state information so that the target stress surface of the lining to be tested and the target stress point on the target stress surface face the longitudinal loading subsystem 2.

[0027] The longitudinal loading subsystem 2 is used to apply a loading pressure of a target pressure value to a target stress point on a target stress surface of the lining to be tested in the longitudinal direction.

[0028] The controllable temperature rise subsystem 4 is used to apply a target temperature to the lining to be tested.

[0029] The embodiment of the present application can solve the problem of loading each point and angle of each tunnel structure, and can simulate the stress of each tunnel structure under the same fire condition, and can safely and reliably carry out high-temperature mechanical performance tests of tunnel lining structure systems. The present application can also carry out loading / heating tests on other structures in the tunnel (upper lane slabs, crash stones, columns, beams, etc.), which helps to more comprehensively understand the overall situation of the tunnel when a fire occurs.

[0030] In one possible implementation, referring to Figure 1 The tunnel multi-structure thermal-mechanical coupling test system may further include a self-reaction frame 5. The self-reaction frame 5 is connected to the longitudinal loading subsystem 2 and is used to bear the reverse force of the loading pressure applied by the longitudinal loading subsystem 2 to the lining to be tested.

[0031] Reference Figure 2 The self-reaction frame 5 may include a first group of columns 51, a second group of columns 52, a main beam 53, a first beam 54, a second beam 55, a first triangular plate 56, a second triangular plate 57 and a bottom base 58. The first group of columns 51 includes a first main column 511, a first column 512 and a second column 513, and the second group of columns 52 includes a second main column 521, a third column 522 and a fourth column 523.

[0032] The top ends of the first main column 511, the first column 512 and the second column 513 are fixedly connected to the first crossbeam 54, and the first main column 511 is located in the middle position between the first column 512 and the second column 513, and the bottom ends of the first main column 511, the first column 512 and the second column 513 are all connected to the ground.

[0033] The top ends of the second main column 521, the third column 522 and the fourth column 523 are all fixedly connected to the second cross beam 55, and the second main column 521 is located in the middle position between the third column 522 and the fourth column 523, and the bottom ends of the second main column 521, the third column 522 and the fourth column 523 are all connected to the ground.

[0034] The main beam 53 is fixed between the first beam 54 and the second beam 55, and the first end of the main beam 53 is fixed at the first position of the first beam 54, and the second end of the main beam 53 is fixed at the first position of the second beam 55. The first position is the middle position of the first beam 54 and the second beam 55 in the length direction.

[0035] The first triangular plate 56 is fixedly connected to the first main column 511 and the main beam 53 , and the second triangular plate 57 is fixedly connected to the second main column 521 and the main beam 53 .

[0036] The side surface of the first main column 511 is fixedly connected to the first end of the bottom base 58, and the side surface of the second main column 521 is fixedly connected to the second end of the bottom base 58. The first end of the bottom base 58 and the second end of the bottom base 58 are opposite ends.

[0037] Among them, the fixed connections of various parts of the self-reaction frame are all connected by bolts and welding to ensure the stability and safety of the test device, including the fixed connection between the column and the beam, the fixed connection between the main beam and the secondary beam, the fixed connection between the triangle plate and the column and the beam, and the fixed connection between the column and the bottom base. For example, the top ends of the first main column, the first column and the second column are fixedly connected to the first beam by welding and bolts.

[0038] Optionally, the embodiment of the present application constructs a self-reaction frame for the purpose of bearing, placing and fixing other structures, and at the same time bearing the reverse force of the loading pressure applied to the lining to be tested by the longitudinal loading subsystem.

[0039] In one possible implementation, referring to Figure 3 The longitudinal loading subsystem 2 may include a pressure head 21 , a first sensor 22 , a hydraulic press 23 and a first connecting plate 24 .

[0040] The upper surface of the first connecting plate 24 is connected to the lower surface of the main cross beam 53, the lower surface of the first connecting plate 24 is connected to the upper end of the hydraulic press 23, the lower end of the hydraulic press 23 is connected to the pressure head 21, and the first sensor 22 is located in the hydraulic press 23 ( Figure 3 The first sensor 22 is not shown in the figure).

[0041] Among them, since a slide rail is provided on the lower surface of the main beam, which is slidably connected to the longitudinal loading subsystem, the purpose of loading all surfaces, points and angles of the lining is achieved through the movement of the longitudinal loading subsystem and the coordinated adjustment of the sample fixing subsystem.

[0042] In a possible implementation, the central control subsystem is used to send the target pressure value to the first sensor;

[0043] The first sensor is used to control the hydraulic press to drive the pressure head to apply a loading pressure of a target pressure value to a target stress point on a target stress surface of the lining to be tested in the longitudinal direction.

[0044] Among them, the central control subsystem is also used to obtain the target movement data of the longitudinal loading subsystem, and send the target movement data to the longitudinal loading subsystem so that it can move to the required position of the longitudinal loading subsystem according to the target movement data through the slide rail.

[0045] Correspondingly, after receiving the target pressure value, the first sensor controls the hydraulic press to drive the pressure head to apply a loading pressure of the target pressure value to the target stress point on the target stress surface of the lining to be measured in the longitudinal direction.

[0046] In a possible implementation, the target angle may include a first target angle and a second target angle, and the target height may include a first target height and a second target height.

[0047] Reference Figure 4 The sample fixing subsystem 3 may include a first lining fixing subsystem 31 , a second lining fixing subsystem 32 , a first lifting device 33 and a second lifting device 34 .

[0048] The first lining fixing subsystem 31 is fixed on the first lifting device 33, and the first lifting device 33 is located on the first side of the bottom base 58. The second lining fixing subsystem 32 is fixed on the second lifting device 34, and the second lifting device 34 is located on the second side of the bottom base 58. The first side and the second side are opposite sides.

[0049] The first lining fixing subsystem 31 is used to clamp the first end of the lining to be tested and rotate it to a first target angle, and the second lining fixing subsystem 32 is used to clamp the second end of the lining to be tested and rotate it to a second target angle to drive the surface of the lining to be tested facing the longitudinal loading subsystem 2 to the target force-bearing surface.

[0050] The first lifting device 33 is used to adjust the first lining fixing subsystem 31 to reach a first target height, where the first target height is the height of the first lining fixing subsystem 31 relative to the bottom base 58 .

[0051] The second lifting device 34 is used to adjust the second lining fixing subsystem 32 to reach a second target height, where the second target height is the height of the second lining fixing subsystem 32 relative to the bottom base 58 .

[0052] The first lining fixing subsystem and the first lifting device are distributed on the first side of the bottom base, the second lining fixing subsystem and the second lifting device are distributed on the second side of the bottom base, and the first side and the second side are opposite sides. In addition, the first end of the lining to be tested and the second end of the lining to be tested are also opposite ends.

[0053] Each lifting device is connected to the bottom base and the main column of the self-reaction frame by welding and bolts.

[0054] Optionally, the embodiment of the present application utilizes a sample fixing subsystem to fix the tunnel lining to be tested, and a lifting device to place the lining to be tested at a desired position, and cooperates with the longitudinal loading subsystem to realize loading tests on various surfaces, points, and angles of tunnel structures of different sizes.

[0055] It should be clarified that the first lining fixing subsystem and the second lining fixing subsystem have the same structure, and the first lifting device and the second lifting device also have the same structure.

[0056] In one possible implementation, referring to Figure 5 The first lining fixing subsystem 31 may include a rotatable transverse arm 311 , a clamp 312 , a lower support frame 313 and a second connecting plate 314 .

[0057] The clamping head 312 is fixed to the first end of the rotatable transverse arm 311 by means of a lower support frame 313 .

[0058] The second end of the rotatable transverse arm 311 is fixedly connected to the second connecting plate 314 .

[0059] The second connecting plate 314 is fixedly connected to the first lifting device 33 .

[0060] Optionally, the embodiment of the present application utilizes a chuck to clamp the lining to be tested, and adjusts the surface of the lining to be tested facing the longitudinal loading subsystem to the target force-bearing surface by rotating the transverse arm.

[0061] In one possible implementation, referring to Figure 1 The sample fixing subsystem may further include a gantry 35 .

[0062] An image collector with adjustable viewing angle is installed in the middle position of the upper part of the gantry and on the side column. The specific position of the tunnel lining can be determined by the image collector for the installation of the lining to be tested.

[0063] In addition, during the test, the image acquisition device identifies the exact position of the lining to be tested, the gantry automatically lifts the lining to be tested, and moves it slowly and steadily to the vicinity of the test system. The mechanical arm then places the lining to be tested on the bottom base, and the rotatable transverse arm is rotated to achieve loading on all sides of the lining to be tested. Subsequently, the lifting device and the extension and retraction of the transverse arm are used to control the lining to be tested to reach the required angle for the test, and then loading is carried out.

[0064] The embodiment of the present application can realize loading on each surface, point and angle of the tunnel lining through the sample fixing subsystem, and can more accurately simulate the actual tunnel stress environment and draw more reliable conclusions.

[0065] In one possible implementation, referring to Figure 6 The controllable temperature-increasing subsystem 4 may include a gas storage tank 41 , a first controller 42 , a box-type temperature-increasing device 43 and a ventilation duct 44 .

[0066] The gas storage tank 41 is connected to the box-type temperature increasing device 43 through the ventilation pipe 44 , and the gas storage tank 41 is connected to the first controller 42 for communication.

[0067] The box-type heating device 43 is fixed below the bottom base.

[0068] The box-type heating device is located in the middle below the bottom base, which is convenient for heating the lining to be tested and ensures that the lining to be tested is heated evenly. The box-type heating device and the bottom base are connected by bolts and welding.

[0069] Optionally, the box-type heating device is connected to the bottom base of the self-reaction frame by bolts and welding, and the gas storage tank is connected to the box-type heating device through a pipeline, and connected to the first controller and controlled by a computer. During the test, the purpose of controllable heating is achieved by receiving the target temperature sent by the central control subsystem and notifying the gas flow rate. The embodiment of the present application can ensure the stability and reliability of the test temperature and the safety of the test through the controllable heating subsystem.

[0070] In one possible implementation, referring to Figure 7 , the box-type heating device 43 may include a box body;

[0071] The box body comprises an outer shell 431 , a heat-insulating layer 432 and a temperature-reducing layer 433 from the inside to the outside.

[0072] The ventilation pipe 44 passes through the first side surface of the box body to connect the gas storage tank 41 with the box-type heating device 43. The first side surface is any side surface of the box body except the upper and lower top surfaces.

[0073] Among them, the ventilation duct is composed of multiple ones.

[0074] Optionally, the box-type heating device comprises a box body, which is composed of an outer shell, an intermediate heat-insulating layer, and an internal cooling layer, wherein two ventilation ducts are provided on both sides of the rear of the box-type heating device and are connected to the ventilation equipment.

[0075] A ventilation pipeline is arranged on the first side of the box-type heating device and is connected to the gas storage tank.

[0076] A temperature sensor and a collection device are arranged in the box-type heating device.

[0077] A device for controlling the gas flow is arranged outside the ventilation duct. This structure can determine the test temperature, reliability and safety of the test.

[0078] Among them, the temperature sensor, collection device and gas flow control device are not in Figure 7 It is reflected in.

[0079] In one possible implementation, referring to Figure 1 The tunnel multi-structure thermal-mechanical coupling test system may also include a cooling subsystem 6 for temperature reduction treatment.

[0080] Reference Figure 8The cooling subsystem 6 may include a water storage tank 61 , a water pipe 62 and a blower 63 .

[0081] The blower 63 is connected to the water storage tank 61 .

[0082] The water storage tank 61 is connected to the box-type heating device 43 by using a water pipe 62 to pass through the second side of the box body. The second side is any side other than the first side.

[0083] In the embodiment of the present application, the water pipes include multiple ones. The water pipes connecting the water storage tank and the box-type heating device are actually connected to the cooling layer in the box body, and accordingly, a cooling pipe is provided on the second side of the box-type heating device, which is connected to the cooling subsystem.

[0084] Optionally, during the test or after the test, when cooling is required, the water supply of the water outlet of the cooling subsystem is controlled by a computer to lower the temperature in the box-type heating device.

[0085] In a possible implementation, the tunnel multi-structure thermal-mechanical coupling test system may further include a data acquisition subsystem for acquiring and transmitting data, wherein the data acquisition subsystem includes a micrometer, a thermal sensor, and a pressure sensor.

[0086] The micrometer is arranged on the longitudinal loading subsystem and is used to collect the longitudinal displacement data of the target stress point on the target stress surface of the lining to be tested.

[0087] The thermal sensor is arranged in the controllable temperature rise subsystem to collect the temperature data in real time when the lining to be tested is cracked during the test.

[0088] The pressure sensor is arranged in the longitudinal loading subsystem and is used for real-time acquisition of the loading pressure applied by the longitudinal loading subsystem to the target stress point on the target stress surface of the lining to be tested.

[0089] In this embodiment of the present application, the data acquisition subsystem also includes a computer.

[0090] Reference Fig. 9 The micrometer 71 is installed on the side of the longitudinal loading subsystem, and the pressure sensor 72 is installed inside the longitudinal loading subsystem.

[0091] During the test, the longitudinal displacement data of the lining to be tested is measured by a micrometer, the pressure sensor is responsible for measuring the loading pressure applied by the longitudinal loading subsystem, and the thermal sensor obtains the temperature data when the lining to be tested breaks during the test, and all the data are transmitted to the computer for storage through the sensors.

[0092] The embodiments of the present application can adapt to a variety of working conditions, such as heating up first and then loading, loading first and then heating up, or loading during the heating process. In addition to conveniently conducting mechanical property tests on the tunnel lining structure system at high temperature (after high temperature), it can also conduct mechanical property tests at room temperature.

[0093] In addition, the embodiments of the present application can realize the mechanical performance test of the tunnel structure at (after) high temperature under different surface-stress point-angle-temperature-load conditions, and can also realize the research and analysis of the damage of fire to the tunnel lining structure system under different fire scenarios, as well as the effective fire resistance measures of the structural system. At the same time, based on the numerical simulation results, the performance test of various parts of the tunnel when simulating a fire can be carried out.

[0094] In one possible implementation, the central control subsystem is located in the control room to ensure the safety of the test personnel. It can perform numerical simulation analysis on the tunnel structure under various disaster conditions, obtain the weak points, force direction, temperature, etc. of each structure, and determine the fixed position of the lining to be tested for the sample fixing subsystem.

[0095] Among them, the central control subsystem includes a controller, numerical simulation equipment and transmission equipment. During the test, various disasters in the tunnel (fire, impact, collapse, etc.) are analyzed.

[0096] After simulating the test conditions and understanding the stress characteristics and weak points of each tunnel structure under these conditions, the temperature, heating rate, load (displacement) loading conditions, etc. required for the test are set on the controller and transmitted to the longitudinal loading subsystem, specimen fixing subsystem and controllable heating subsystem.

[0097] The specific process of obtaining the required temperature, pressure and status information of the lining to be tested is as follows:

[0098] Step 101, obtaining the tunnel structure, the composition of each structural material and performance parameters.

[0099] The embodiment of the present application can obtain tunnel data and tunnel disaster test cases in an actual tunnel by wired or wireless means. The tunnel disaster test cases may include tunnel disaster test information and test samples. The tunnel disaster test cases may be information used to establish a disaster scenario in a three-dimensional digital twin model of a tunnel for simulation processing.

[0100] It should be noted that the wireless connection methods proposed above may include but are not limited to 3G / 4G / 5G connections, WiFi connections, and other wireless connection methods currently known or to be developed in the future.

[0101] Step 102, using the acquired tunnel structure, the composition of each structural material and the performance parameters, a three-dimensional digital twin model of the tunnel is established, and tunnel data and tunnel disaster test cases are input to simulate the tunnel disaster scenario to obtain a tunnel model under the disaster state.

[0102] The three-dimensional digital twin model of the tunnel can be established in proportion to the actual tunnel. The data in the tunnel model under disaster conditions can be updated according to the state changes of the tunnel disaster scene to simulate the changes in the data in the tunnel during the tunnel disaster process.

[0103] The tunnel data mentioned above is a set of information about each structure in the tunnel over a period of time. The tunnel disaster test information included in the tunnel disaster test case may include: disaster test type, disaster test vector coordinates, disaster test level, and disaster data to be tested corresponding to one or more disaster scenarios. Here, the disaster test type may be a disaster type mark. For example, the disaster type may include but is not limited to at least one of the following: fire type, impact type, and collapse type. In practice, if the disaster test coordinates are not set, the disaster test coordinates can be randomly generated.

[0104] The disaster test level may be a fire level, where the fire level may be defined in advance according to the flame range when the fire is detected, and this embodiment does not make a specific limitation. In addition, the disaster data to be tested corresponding to one or more disaster scenarios may represent one or more disaster scenarios that need to be tested in the current simulation test.

[0105] The above-mentioned three-dimensional digital twin model of the tunnel may include: simulated tunnel lining, beams, upper lane slabs, columns, anti-collision plates, etc.

[0106] The specific implementation process is as follows:

[0107] First, the structural models corresponding to each structure in the tunnel data are injected into the three-dimensional digital twin model of the tunnel. The density, tensile and compressive damage parameters, thermal damage parameters, thermal coefficients, etc. are set on each structure in the three-dimensional digital twin model of the tunnel to characterize the structural performance in the three-dimensional digital twin model of the tunnel.

[0108] Second, the tunnel disaster test information included in the tunnel disaster test case is injected into the tunnel three-dimensional digital twin model, so that at the disaster test coordinate position included in the tunnel disaster test information, according to the disaster test type and the disaster test level, the data of the disaster test coordinate position is adjusted to obtain the adjusted data. Among them, a disaster map can be generated at the disaster test coordinate position according to the disaster test type and the disaster test level.

[0109] For example, if the disaster test type is a simultaneous occurrence of fire, impact, and collapse, a three-dimensional thermal map, impact load map, and collapse load map are generated along the tunnel direction. The final thermal-mechanical coupling three-dimensional view is generated through the constitutive model, mechanical properties, thermal coefficients of each structure, and interface bonding parameters between the structures. The heat and stress of each structure are calculated, the dangerous points in each structure are marked, and the temperature, load size, and force direction of the point are explained.

[0110] If the disaster type is other than fire, impact, collapse, etc., the disaster map can also be generated according to the above method.

[0111] Step 103, based on the results of the numerical simulation of the three-dimensional digital twin model of the tunnel, the sample fixing subsystem, the longitudinal loading subsystem and the controllable heating subsystem are used to simulate the actual disaster conditions and test the dangerous points of each structure of the tunnel. That is, the results of the simulation of the three-dimensional digital twin model of the tunnel are sent to the sample fixing subsystem, the longitudinal loading subsystem and the controllable heating subsystem through the central control subsystem for testing.

[0112] First, determine the test structure, and automatically identify the tunnel structure through the sample fixing subsystem. The gantry will lift the sample and slowly move it to the vicinity of the sample table. The robotic arm will automatically clamp the sample and cooperate with the lifting platform to fix the sample according to the required loading surface, position and angle.

[0113] Then, for the samples that need to be heated, the controllable heating subsystem heats the samples to the required temperature, and then the longitudinal loading subsystem loads the samples.

[0114] Finally, after the experiment, the cooling subsystem cools the device down to room temperature.

[0115] The embodiment of the present application uses a central control system to simulate the stress characteristics of each structure of the tunnel when a fire occurs, grasp the stress conditions of each structure of the tunnel, and quickly conduct accurate tests on the weak parts based on the simulation results. At the same time, the central control system automates the overall test, using program control and automatic data acquisition technology to reduce human errors, improve work efficiency, reduce labor costs, and improve the safety of the test.

[0116] Based on the above discussion, it can be seen that the tunnel multi-structure thermal coupling test system can accomplish the following functions in the embodiment of the present application:

[0117] (1) The system can be used to conduct a wide range of mechanical property tests on tunnel lining structure systems at (or after) high temperatures; the propagation and distribution law of temperature field within the tunnel segment structure system; the safety, damage form, damage mechanism and weak links of tunnel lining segment structures and other load-bearing structures under different fire scenarios and stress conditions; the overall deformation, stability and bearing capacity of tunnel structures at and after high temperatures: the permanent deformation caused by the post-fire structure system and its impact on the surrounding environment; the fire resistance limit of the lining structure system under different fire scenarios and stress conditions; and the effectiveness test of different repair and reinforcement methods for the post-fire lining structure system.

[0118] (2) This system can be used to conduct high temperature mechanical performance tests on various concrete, reinforced concrete, steel fiber concrete, ultra-high performance concrete, and steel structure systems. The shape of the tunnel segment structure system is arc-shaped. At the same time, due to the use of horizontal temperature increase loading, larger-sized structural systems can also be tested conveniently.

[0119] (3) This system can be used to test the mechanical properties of tunnel segments and steel structure systems at high temperatures (the load-temperature path can be used, which is loading first and then heating or heating first and then loading), and can also be used to test the mechanical properties of lining structures after high temperatures. At the same time, the mechanical properties of tunnel segments and steel structure systems at room temperature can also be tested.

[0120] (4) The maximum heating temperature of this system can reach 1350℃, and the maximum heating rate can reach 250℃ / min. This well reflects the characteristics of fast heating rate and high maximum temperature of tunnel fire. At the same time, through program control, it can simulate a variety of internationally used standard temperature-time curves, such as RABT, RWS, HC standard curves, etc. Taking the HC standard curve as an example, actual tests show that this test system can simulate well.

[0121] The present application provides a tunnel multi-structure thermal-mechanical coupling test system, which integrates multiple subsystems such as longitudinal loading, sample fixing and controllable heating through a central control subsystem, realizes a high degree of automation of the experimental process, simplifies the operation process, and improves the accuracy and efficiency of the test; then, the central control subsystem can accurately determine the target pressure value, target state information and target temperature according to the input target working condition and send them to the corresponding system, so that the system can more accurately simulate the stress state and temperature change of the tunnel lining in the actual working environment, thereby providing more reliable test data; in addition, the sample fixing subsystem can adjust the angle and height of the lining to be tested according to the target state information to ensure that the target stress surface and the target stress point thereon are facing the longitudinal loading subsystem. This flexibility and adaptability make the system applicable to tunnel lining tests of different types and sizes, greatly enhancing the versatility and practicality of the system; at the same time, by combining the longitudinal loading and controllable heating functions, the system can simultaneously simulate the coupling effect of the tunnel lining under stress and temperature change, which is helpful to more comprehensively evaluate the performance and safety of the tunnel lining, and provide strong technical support for the design and construction of tunnel engineering.

[0122] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0123] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A tunnel multi-structure thermal-mechanical coupling test system, characterized in that: It includes a central control subsystem, a longitudinal loading subsystem, a sample fixing subsystem and a controllable temperature rising subsystem, wherein the central control subsystem is respectively connected to the longitudinal loading subsystem, the sample fixing subsystem and the controllable temperature rising subsystem in communication; The central control subsystem is used to obtain the target working condition of the lining to be tested, determine the target pressure value, target state information and target temperature of the lining to be tested based on the target working condition, and send the target pressure value to the longitudinal loading subsystem, send the target state information to the sample fixing subsystem, and send the target temperature to the controllable temperature rising subsystem, wherein the target state information includes a target angle and a target height; The sample fixing subsystem is used to clamp the lining to be tested, and adjust the angle and height of the lining to be tested according to the target state information, so that the target force-bearing surface of the lining to be tested and the target force-bearing point on the target force-bearing surface face the longitudinal loading subsystem; The longitudinal loading subsystem is used to apply a loading pressure of the target pressure value to a target stress point on a target stress surface of the lining to be tested in the longitudinal direction; The controllable temperature rise subsystem is used to apply the target temperature to the lining to be tested; Wherein, the tunnel multi-structure thermal coupling test system further includes a self-reaction force frame, and the self-reaction force frame includes a bottom base; the target angle includes a first target angle and a second target angle, the target height includes a first target height and a second target height, and the sample fixing subsystem includes a first lining fixing subsystem, a second lining fixing subsystem, a first lifting device and a second lifting device; The first lining fixing subsystem is fixed to the first lifting device, and the first lifting device is located on a first side of the bottom base, the second lining fixing subsystem is fixed to the second lifting device, and the second lifting device is located on a second side of the bottom base, and the first side and the second side are opposite sides; The first lining fixing subsystem is used to clamp the first end of the lining to be tested and rotate it to the first target angle, and the second lining fixing subsystem is used to clamp the second end of the lining to be tested and rotate it to the second target angle to drive the surface of the lining to be tested facing the longitudinal loading subsystem to the target force-bearing surface; The first lifting device is used to adjust the first lining fixing subsystem to reach the first target height, and the first target height is the height of the first lining fixing subsystem relative to the bottom base; The second lifting device is used to adjust the second lining fixing subsystem to reach the second target height, and the second target height is the height of the second lining fixing subsystem relative to the bottom base; Wherein, the first lining fixing subsystem comprises a rotatable transverse arm, a clamp, a lower support frame and a second connecting plate; The chuck is fixed to the first end of the rotatable transverse arm by means of the lower support frame; The second end of the rotatable transverse arm is fixedly connected to the second connecting plate; The second connecting plate is fixedly connected to the first lifting device.

2. The tunnel multi-structure thermal-mechanical coupling test system according to claim 1 is characterized in that: The self-reaction frame is connected to the longitudinal loading subsystem; it is used to bear the reverse force of the loading pressure applied to the lining to be tested by the longitudinal loading subsystem; the self-reaction frame includes a first group of columns, a second group of columns, a main beam, a first beam, a second beam, a first triangular plate, and a second triangular plate; the first group of columns includes a first main column, a first column, and a second column; the second group of columns includes a second main column, a third column, and a fourth column; The top ends of the first main column, the first column and the second column are all fixedly connected to the first crossbeam, and the first main column is located in the middle of the first column and the second column, and the bottom ends of the first main column, the first column and the second column are all connected to the ground; The top ends of the second main column, the third column and the fourth column are all fixedly connected to the second cross beam, and the second main column is located in the middle of the third column and the fourth column, and the bottom ends of the second main column, the third column and the fourth column are all connected to the ground; The main crossbeam is fixed between the first crossbeam and the second crossbeam, and the first end of the main crossbeam is fixed at a first position of the first crossbeam, and the second end of the main crossbeam is fixed at a first position of the second crossbeam, and the first position is a middle position of the first crossbeam and the second crossbeam in the length direction; The first triangular plate is fixedly connected to the first main column and the main beam, and the second triangular plate is fixedly connected to the second main column and the main beam; The side surface of the first main column is fixedly connected to the first end of the bottom base, the side surface of the second main column is fixedly connected to the second end of the bottom base, and the first end of the bottom base and the second end of the bottom base are opposite ends.

3. The tunnel multi-structure thermal-mechanical coupling test system according to claim 2 is characterized in that: The longitudinal loading subsystem includes a pressure head, a first sensor, a hydraulic press and a first connecting plate; The upper surface of the first connecting plate is connected to the lower surface of the main beam, the lower surface of the first connecting plate is connected to the upper end of the hydraulic press, the lower end of the hydraulic press is connected to the pressure head, and the first sensor is located in the hydraulic press.

4. The tunnel multi-structure thermal-mechanical coupling test system according to claim 3 is characterized in that: The central control subsystem is used to send the target pressure value to the first sensor; The first sensor is used to control the hydraulic press to drive the pressure head to apply a loading pressure of the target pressure value to a target stress point on a target stress surface of the lining to be tested in the longitudinal direction.

5. The tunnel multi-structure thermal-mechanical coupling test system according to claim 1 is characterized in that: The controllable temperature-raising subsystem includes a gas storage tank, a first controller, a box-type temperature-raising device and a ventilation pipeline; The gas storage tank is connected to the box-type heating device through the ventilation pipe, and the gas storage tank is in communication with the first controller; The box-type heating device is fixed below the bottom base.

6. The tunnel multi-structure thermal-mechanical coupling test system according to claim 5 is characterized in that: The box-type heating device comprises a box body; The box body comprises an outer shell, a heat-insulating layer and a cooling layer from the inside to the outside; The ventilation duct passes through a first side surface of the box body so that the gas storage tank is connected to the box-type heating device. The first side surface is any side surface of the box body except the upper and lower top surfaces.

7. The tunnel multi-structure thermal-mechanical coupling test system according to claim 6, characterized in that: The tunnel multi-structure thermal coupling test system also includes a cooling subsystem for temperature reduction treatment, and the cooling subsystem includes a water storage tank, a water pipeline and a blower; The blower is connected to the water storage tank; The water storage tank is connected to the box-type heating device by passing the water conduit through the second side of the box body, and the second side is any side except the first side.

8. The tunnel multi-structure thermal-mechanical coupling test system according to claim 1 is characterized in that: The tunnel multi-structure thermal-mechanical coupling test system also includes a data acquisition subsystem for collecting and transmitting data, and the data acquisition subsystem includes a micrometer, a thermal sensor, and a pressure sensor; The micrometer is arranged on the longitudinal loading subsystem and is used to collect the displacement data of the target force-bearing point on the target force-bearing surface of the lining to be tested in the longitudinal direction; The thermal sensor is arranged in the controllable temperature rise subsystem, and is used to collect temperature data in real time when the lining to be tested is cracked during the test; The pressure sensor is arranged in the longitudinal loading subsystem, and is used for collecting in real time the loading pressure applied by the longitudinal loading subsystem to the target stress point on the target stress surface of the lining to be tested.

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