Construction method and experimental method of large experimental model for thermophysical response of rock mass structure

Abstract

The invention provides a building method and an experiment method of a large experimental model for thermophysical response of a rock mass structure, and the method comprises the steps: laying a simulated rock mass bottom layer frame through regular granite base blocks with different specifications and sizes, and reserving and building transverse fracture vacancies and longitudinal fractures with different lengths on a group of opposite edges of the simulated rock mass bottom layer frame; according to the experimental method, the surface image of the experimental model is obtained through shooting of the unmanned aerial vehicle, the thermal infrared information of the real mountain is obtained through shooting of the unmanned aerial vehicle, and the crack condition of the real mountain can be predicted by comparing the obtained infrared information of the crack of the model with the infrared information of the real mountain. And meanwhile, through the combination of the temperature and humidity information and the infrared information of the model, the humidity and cracks in a real mountain are predicted, mountain peeling hazards caused by large cracks and large humidity can be prevented in advance, and meanwhile, through the combination of the temperature and humidity information and the infrared information of the model, the heat conduction characteristic of a rock mass structure can be comprehensively monitored.

Description

Technical Field

[0001] The invention relates to the field of rock mass structure exploration, and in particular to a method for building a large-scale experimental model of thermal physical response of a rock mass structure. Background Art

[0002] The stability and integrity of rock mass structure are the key to geothermal energy development, CO 2 It is an important research topic in the fields of geological storage, groundwater seepage, slope stability, etc. In these fields, the formation and development of rock cracks and the migration behavior of water vapor have an important influence on the mechanical properties and stability of the rock mass. In order to gain a deeper understanding of the behavioral characteristics of rock cracks, experimental and numerical simulation studies are usually required. In the natural environment, the formation and development of rock cracks are affected by many factors, including natural stress fields, temperature changes, and humidity conditions. Although existing indoor experiments can accurately control the experimental conditions, it is often difficult to fully simulate the complex conditions in the natural environment. At the same time, the scale is relatively small, and there is no physical model that can simulate large-scale rock structures in the field. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a method for constructing a large-scale experimental model of the thermal physical response of rock mass structure.

[0004] S1: A simulated rock mass bottom frame is laid by regular granite foundation blocks of different sizes, and transverse crack spaces of different lengths are reserved on a group of relative sides of the simulated rock mass bottom frame. Several layers of crack simulation modules of corresponding lengths are stacked at the transverse crack spaces of different lengths, and filling layers are placed between the stacked crack simulation modules. The filling layers of the upper two layers form four groups of thick transverse cracks, and the filling layers of the lower two layers form four groups of thin transverse cracks; the four groups of transverse cracks in the upper two layers are filled with sand, soil, and a mixture of sand and soil, and one group is left vacant, and the four groups of transverse cracks in the lower two layers are filled with sand, soil, and a mixture of sand and soil, and one group is left vacant;

[0005] S2: Continue to lay a multi-layer structure along the height direction of the simulated rock mass bottom frame through granite foundation blocks, leaving gaps between the stacked granite foundation blocks to form longitudinal cracks, the longitudinal cracks extending from the side of the simulated rock mass bottom frame to the inside; the longitudinal cracks are located on another set of opposite sides of the simulated rock mass bottom frame;

[0006] S3: Set up water vapor field monitoring units in transverse cracks, longitudinal cracks and granite base blocks.

[0007] Preferably, the simulated rock mass bottom layer framework comprises a first opposite side and an opposite second opposite side, the transverse crack vacancies are respectively located at the two first opposite sides, and the longitudinal cracks are respectively located at the two second opposite sides.

[0008] Preferably, the longitudinal cracks located on one second opposite side have the same crack width and different extension lengths, and the longitudinal cracks located on the other second opposite side have the same extension lengths and different crack widths.

[0009] Preferably, in S3, the water vapor field monitoring unit is also arranged in the granite, a hole is opened on the granite base block at the placement position, and the communication line of the water vapor field monitoring unit is led out from the hole and externally connected to the collection terminal.

[0010] Preferably, the hole is filled with epoxy resin material.

[0011] Preferably, the fracture simulation module is composed of an arrangement of granite blocks.

[0012] Preferably, several groups of water vapor field monitoring units are arranged in each group of transverse cracks, longitudinal cracks and granite.

[0013] Preferably, the water vapor field monitoring unit is located at the 1 / 8 position in the direction perpendicular to the crack surface and the 1 / 4 position parallel to the crack surface of each transverse crack, with two symmetrically arranged sensors. Three sensors are also arranged at the center position of each transverse crack and at two corner positions close to the inside. A total of five sensors are arranged in each transverse crack.

[0014] Preferably, the water vapor field monitoring units include 6 units, 2 of which are located at the 1 / 8 position on both sides of each longitudinal crack in the direction perpendicular to the crack surface, 2 are located at the 1 / 2 position on the center line of the longitudinal crack in the direction perpendicular to the crack surface, and 2 are located at two corner positions close to the inside.

[0015] An experimental method for the thermophysical response of rock structures.

[0016] S1: Build the aforementioned experimental model outdoors, monitor the temperature and humidity information of cracks of various sizes and the entire model in real time through the water vapor field monitoring units in the horizontal gaps and longitudinal gaps, and derive the analysis and processing to obtain the spatiotemporal distribution and dynamic change characteristics of the temperature and humidity of the model;

[0017] S2: Obtain the surface image of the experimental model by taking photos with a drone, and use the high-resolution thermal infrared camera and image analysis software on the drone to take photos of the thermal infrared information of the side of the experimental model on four sides of the experimental model respectively; the route planning photography is carried out on the top of the model, and the flight route is set in advance to allow it to automatically fly and collect thermal infrared information on the top of the model; the image analysis software analyzes and processes the image acquisition information to obtain the thermal infrared information of the surface of the experimental model, especially the cracks; and record the different humidity corresponding to different infrared information positions;

[0018] S3: The thermal infrared information of the real mountain is obtained through the automatic flight route of the drone. By comparing the thermal infrared characteristics of the experimental model with the thermal infrared characteristics of the rock, it is quickly determined whether there are cracks in the slope. At the same time, the temperature and humidity information obtained by the temperature and humidity sensors of the model and the thermal infrared image acquisition data are combined to record the corresponding relationship between temperature and humidity and infrared images, monitor the thermal conduction characteristics of the rock structure, and predict the humidity and cracks inside the real rock based on the temperature and humidity information of the model and the infrared image acquisition data.

[0019] The construction method and experimental method of the large-scale experimental model of the thermal physical response of the rock structure proposed in the present invention have the following beneficial effects: the large-scale physical experimental model is placed outdoors to fully simulate the complex conditions in the natural environment and obtain the data closest to the field site. A number of natural regular granite blocks are used to build a model to truly reproduce the shape and characteristics of the field rock slope. The rock fracture simulation module fills part of the transverse fractures with soil and sand materials to simulate fractures with different parameters in the field. By comparing the infrared information detected by the model with the infrared information obtained by the detection of the real mountain, the internal fracture conditions of the real mountain can be predicted, thereby preventing the two rocks and the fractures in the middle in advance to prevent disasters such as spalling from occurring and causing harm to people.

[0020] At the same time, combined with the temperature and humidity data obtained by the temperature and humidity sensors installed in the model, we can know what thermal infrared characteristics the cracks will present when the humidity is too high. After extending this characteristic to the wild mountains, we can take precautions in advance against these two rocks and the cracks in the middle to prevent disasters such as peeling. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0022] Figure 1 It is a general schematic diagram of the experimental model in a specific embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the first layer construction process of the experimental model in a specific embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of the bottom frame of the rock mass in a specific embodiment of the present invention;

[0025] Figure 4 Schematic diagram of each crack simulation module in a specific embodiment of the present invention;

[0026] Figure 5 It is a top view schematic diagram of the layout points of the first and fourth layers of the water vapor field monitoring unit of the monitoring module in a specific embodiment of the present invention;

[0027] Figure 6It is a top view schematic diagram of the second and third layer layout points of the water vapor field monitoring unit of the monitoring module in a specific embodiment of the present invention;

[0028] Figure 7 This is a working principle diagram of the infrared thermal imager in the thermal infrared monitoring unit of the monitoring module in a specific embodiment of the present invention;

[0029] Figure 8 is a flow chart of the experimental method of the present invention;

[0030] Fig. 9 It is a schematic diagram of the arrangement of the water vapor field monitoring unit of the longitudinal crack of the present invention;

[0031] Fig.10 is a schematic diagram of the distribution of fillers on the first opposite side A of the present invention;

[0032] Fig.11 is a schematic diagram of the distribution of fillers on the first opposite side C of the present invention;

[0033] Among them, 1, 2, granite base block; 3, transverse cracks; 41, 42, 43, transverse crack vacancies; 5, longitudinal cracks; 6, water vapor field monitoring unit; 7, filling layer; 71, sand; 72, soil; 73, sand-soil mixture 74, vacant; 8, object; 9, radiation; 10, lens; 11, grating; 12, detector; 13, infrared thermal map. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0035] Example

[0036] The present invention proposes a method for constructing a large-scale experimental model of the thermal physical response of rock mass structure.

[0037] S1: The simulated rock mass bottom frame is laid by regular granite blocks of different sizes, wherein the granite blocks have about 11 sizes. Different granite sizes are selected according to the specific laying size. A set of relative sides of the simulated rock mass bottom frame are reserved for building transverse crack spaces of different lengths, and several layers of crack simulation modules of corresponding lengths are stacked at the transverse crack spaces of different lengths. In this embodiment, the thickness of the thin transverse crack is 1 cm, and the thickness of the thick transverse crack is 3 cm. It can also be designed to other thicknesses, not limited to the above two thicknesses.

[0038] In this embodiment, the structure in this embodiment is as follows Figure 3As shown, of course, it is not limited to the size of this embodiment. Granite blocks are arranged to form a square structure, and three groups of transverse crack vacancies are formed on the opposite sides of the square structure. The sides are defined as the first opposite side A and the first opposite side C, and the two sides without transverse crack vacancies are defined as the second opposite side B and the second opposite side D. The lengths of the three groups of transverse crack vacancies are 50 cm, 100 cm, and 150 cm respectively, and are formed by stacking the crack simulation modules. Specifically, a crack of 50 cm in length is formed by placing a granite block 2 at the transverse crack vacancies 41, and stacking them in the height direction. Similarly, a transverse crack 3 of 100 cm uses four second granites, which are placed in a transverse crack vacancies 42 in a 2*2 pattern. A transverse crack 3 of 150 cm is formed by placing nine second granites in a 3*3 pattern at a transverse crack vacancies 43. Similarly, they are stacked in sequence. A filling layer 7 is set between two adjacent layers. Four filling layers 7 are formed from bottom to top, two of which are 1 cm thick filling layers 7, and two of which are 3 cm thick filling layers 7.

[0039] There are three groups of longitudinal cracks 5 on the second relative surface. The longitudinal cracks 5 refer to the directions vertically set on the ground. The gaps are left in the vertical direction by adjacent stacked granite blocks or granite blocks 2. In this embodiment, the longitudinal cracks 5 are not filled, and the height of the longitudinal cracks 5 is the same at 80 cm. There are four inward extension lengths: 75 cm, 125 cm, 150 cm, and 175 cm, and the widths are 1 cm, 2 cm, and 3 cm respectively. For the three layers of longitudinal cracks 5 as described above, the filling width of the second relative side B is 2 cm, and the inward extension lengths from left to right are 75 cm, 125 cm, and 175 cm respectively; the inward extension length of the second relative side D is 150 cm, and the filling widths from left to right are 1 cm, 2 cm, and 3 cm respectively. Fig.10 , Fig.11 As shown, a filling layer is placed between the stacked crack simulation modules. The thickness of the filling layer of the upper two layers is 3 cm. The two first opposite sides A and the second opposite sides C of each layer have transverse cracks respectively. The two layers form a total of 4 groups of thin transverse cracks. The four groups of transverse cracks are filled with sand 71, soil 72, sand-soil mixture 73 and vacant space 74 respectively. The filling layer of the lower two layers forms 4 groups of thin transverse cracks. The thickness of the four groups of transverse cracks in the lower two layers is 1 cm. The interior is filled with sand 71, soil 72, sand-soil mixture 73 and a group of vacant space 74 respectively, so as to ensure that different fillers have parameter comparisons in different length parameters and thickness parameters of the cracks.

[0040] After the stacking is completed, the final result is as follows Figure 1The structure shown in the figure requires that a water vapor field monitoring unit 6 be set in the transverse gap and the longitudinal gap. The water vapor field monitoring unit 6 uses a high-precision temperature and humidity sensor, which is composed of a collection terminal and a sensor probe, which are connected by a communication line. The sensors are arranged in four layers, which is the same as the number of layers of the transverse cracks 3. The point arrangement of each layer is as follows: Figure 5 , Figure 6 As shown, the first and fourth layers adopt Figure 5 Layout method, the second and third layers adopt Figure 6 The water vapor field monitoring unit is arranged at the 1 / 8 position of each transverse crack in the direction perpendicular to the crack surface, the 1 / 4 position parallel to the crack surface, and the angular position. There are two groups in total and they are arranged symmetrically. There are five water vapor field detection units in each transverse crack. The arrangement on the longitudinal crack is similar to that on the transverse crack, with a total of 6 water vapor field monitoring units, 2 of which are located at the 1 / 8 position of each longitudinal crack in the direction perpendicular to the crack surface on both sides, 2 at the 1 / 2 position of the center line of the longitudinal crack in the direction perpendicular to the crack surface, and 2 at the two corners near the inside. For details, see Fig. 9 , the temperature and humidity information of cracks of various sizes and the model as a whole can be monitored in real time, and can be exported for analysis and processing in order to obtain the temporal and spatial distribution and dynamic change characteristics of the temperature and humidity of the model.

[0041] The setting of the water vapor field monitoring unit 6 requires drilling a 2 cm hole at the corresponding position of each layer of a small number of the granite blocks to facilitate the passage of the probe communication line of the temperature and humidity sensor so that the probe of the temperature and humidity sensor can be extended to the designed point. After the probe communication line of the temperature and humidity sensor passes smoothly through the granite block after the hole is drilled, the gap left on the granite block is sealed with epoxy resin to prevent external water vapor from passing through the gap to affect the experimental data.

[0042] In this embodiment, the thermal infrared monitoring unit is a drone close-up photogrammetry software system, including a high-resolution thermal infrared camera and image analysis software installed on the drone. The thermal infrared camera on the drone collects images of the surface of the physical experimental model in a non-contact manner. The principle of the above-mentioned collection method can refer to the high-steep slope multi-angle close-up photogrammetry method disclosed in the applicant's prior application publication number: CN117664086A. Its working principle is as follows Figure 7As shown, the acquisition method includes route planning and fixed-point shooting, wherein a total of four points are set for fixed-point shooting, which are located on the four sides of the model to capture the thermal infrared information of the side of the model; route planning photography is performed on the top of the model, and the flight route is set in advance to allow it to automatically fly and collect thermal infrared information on the top of the model. The image analysis software analyzes and processes the image acquisition information to obtain thermal infrared information on the surface of the experimental model, especially the cracks. By comparing the thermal infrared characteristics of the cracks with the thermal infrared characteristics of the real mountain rocks, it is helpful to quickly distinguish whether there are cracks in the slope in the field. The presence of rock cracks has an important influence on the mechanical properties and stability of the rock mass. When the cracks are large in scale, the stability of the rock mass will also be reduced, and geological disasters are prone to occur.

[0043] like Figure 8 As shown, the above-mentioned experimental model is built outdoors by the above-mentioned method, and the temperature and humidity information of cracks of various sizes and the entire model are monitored in real time through the water vapor field monitoring unit 6 in the horizontal gap and the longitudinal gap, and the temporal and spatial distribution and dynamic change characteristics of the temperature and humidity of the model are obtained by deriving and analyzing the information;

[0044] The surface image of the experimental model is obtained by drone photography. The thermal infrared information of the side of the experimental model is photographed on four sides of the experimental model by using the high-resolution thermal infrared camera and image analysis software on the drone. The route planning photography is carried out on the top of the model. The flight route is set in advance to allow the drone to automatically fly and collect thermal infrared information on the top of the model. The image analysis software analyzes and processes the image acquisition information to obtain thermal infrared information on the surface of the experimental model, especially on the cracks. The temperature and humidity information of each crack and inside the granite is recorded, and the infrared information, temperature and humidity information corresponding to different crack lengths, thicknesses and different fillings are recorded.

[0045] By using drones to follow automatic flight routes to obtain thermal infrared information of real mountains, and by comparing the thermal infrared characteristics of the experimental model with those of rocks, it is possible to quickly identify whether there are cracks in the slope. Combined with the temperature and humidity information of the model, it is possible to predict the temperature and humidity changes of the model under different environmental conditions. When the humidity is too high, what thermal infrared characteristics will the cracks present? When extended to wild mountains, this characteristic indicates that the cracks in the mountain contain a lot of water, and water plays a lubricating and promoting role in landslides and collapses. Therefore, these two rocks and the cracks in the middle can be prevented in advance to prevent disasters such as spalling, which would cause harm to people.

[0046] At the same time, combined with temperature and humidity sensors and thermal infrared image acquisition data, the thermal conduction characteristics of the rock structure are monitored, which provides an important basis for in-depth research on the thermal physical response of the rock structure surface under different parameters, and then provides an important reference for deducing the internal structure of the rock mass. At the same time, it will also open up new perspectives for analyzing scientific issues such as weathering depth, freeze-thaw cycles and geothermal conduction.

Claims

1. A method for constructing a large-scale experimental model of the thermal physical response of a rock mass structure, characterized in that: S1: A simulated rock mass bottom frame is laid by regular granite foundation blocks of different sizes, and transverse crack spaces of different lengths are reserved on a group of relative sides of the simulated rock mass bottom frame. Several layers of crack simulation modules of corresponding lengths are stacked at the transverse crack spaces of different lengths, and filling layers are placed between the stacked crack simulation modules. The filling layers of the upper two layers form four groups of thick transverse cracks, and the filling layers of the lower two layers form four groups of thin transverse cracks; the four groups of transverse cracks in the upper two layers are filled with sand, soil, and a mixture of sand and soil, and one group is left vacant, and the four groups of transverse cracks in the lower two layers are filled with sand, soil, and a mixture of sand and soil, and one group is left vacant; S2: Continue to lay a multi-layer structure along the height direction of the simulated rock mass bottom frame through granite foundation blocks, leaving gaps between the stacked granite foundation blocks to form longitudinal cracks, the longitudinal cracks extending from the side of the simulated rock mass bottom frame to the inside; the longitudinal cracks are located on another set of opposite sides of the simulated rock mass bottom frame; S3: Set up water vapor field monitoring units in transverse cracks, longitudinal cracks and granite base blocks.

2. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 1, characterized in that: The simulated rock mass bottom frame comprises a first opposite side and an opposite second opposite side, the transverse crack vacancies are respectively located at the two first opposite sides, and the longitudinal cracks are respectively located at the two second opposite sides.

3. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 2, characterized in that: The longitudinal cracks located on one second opposite side have the same crack width and different extension lengths, and the longitudinal cracks located on the other second opposite side have the same extension lengths and different crack widths.

4. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 1, characterized in that: In S3, the water vapor field monitoring unit is also arranged in the granite, a hole is opened on the granite base block at the placement position, and the communication line of the water vapor field monitoring unit is led out from the hole and connected to an external collection terminal.

5. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 5, characterized in that: The holes are filled with epoxy resin material.

6. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 1, characterized in that: The fracture simulation module is composed of an arrangement of granite blocks.

7. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 1, characterized in that: Several groups of water vapor field monitoring units are arranged in each group of transverse cracks, longitudinal cracks and granite.

8. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 7, characterized in that: The water vapor field monitoring unit is located at the 1 / 8 position perpendicular to the crack surface, the 1 / 4 position parallel to the crack surface, and the angular position of each transverse crack. There are five water vapor field detection units in each transverse crack, and they are symmetrically arranged.

9. The large-scale experimental model of the thermophysical response of rock mass structure according to claim 7, characterized in that: The water vapor field monitoring units include 6 units, 2 of which are located at the 1 / 8 position on both sides of each longitudinal crack in the direction perpendicular to the crack surface, 2 are located at the 1 / 2 position on the center line of the longitudinal crack in the direction perpendicular to the crack surface, and 2 are located at the two corners near the inside.

10. An experimental method for the thermophysical response of rock mass structure, characterized in that: S1: Building an experimental model as described in any one of claims 1 to 8 outdoors, monitoring the temperature and humidity information of cracks of various sizes and the model as a whole in real time through the water vapor field monitoring units in the transverse gaps and the longitudinal gaps, and deriving and analyzing the temporal and spatial distribution and dynamic change characteristics of the temperature and humidity of the model; S2: Obtain the surface image of the experimental model by taking photos with a drone, and use the high-resolution thermal infrared camera and image analysis software on the drone to take photos of the thermal infrared information of the side of the experimental model on four sides of the experimental model respectively; the route planning photography is carried out on the top of the model, and the flight route is set in advance to allow it to automatically fly and collect thermal infrared information on the top of the model; the image analysis software analyzes and processes the image acquisition information to obtain the thermal infrared information of the surface of the experimental model, especially the cracks; and record the different humidity corresponding to different infrared information positions; S3: The thermal infrared information of the real mountain is obtained through the automatic flight route of the drone. By comparing the thermal infrared characteristics of the experimental model with the thermal infrared characteristics of the rock, it is quickly determined whether there are cracks in the slope. At the same time, the temperature and humidity information obtained by the temperature and humidity sensors of the model and the thermal infrared image acquisition data are combined to record the corresponding relationship between temperature and humidity and infrared images, monitor the thermal conduction characteristics of the rock structure, and predict the humidity and cracks inside the real rock based on the temperature and humidity information of the model and the infrared image acquisition data.

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