CN114241876A - Experiment method of karst collapse experiment device based on top cover layer with dominant channels - Google Patents
Experiment method of karst collapse experiment device based on top cover layer with dominant channels Download PDFInfo
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Abstract
The invention relates to the field of research on karst collapse technologies, in particular to an experimental method of a karst collapse experimental device based on an upper cover layer containing a dominant channel. The karst collapse experimental device comprises a model box, a rainfall device positioned above the model box, a water supply tank positioned below the model box, a first variable water head tank and a second variable water head tank, wherein the first variable water head tank and the second variable water head tank are positioned on two sides of the model box and are adjustable in height; a partition plate is horizontally arranged in the middle of the model box to divide the model box into an upper cover layer model box and a lower karst cave model box; clay blocks are uniformly paved in the cover layer model box; the first water outlet pipe is communicated with a first variable water head tank, the second water outlet pipe is communicated with a second variable water head tank, and the third water outlet pipe is communicated with a rainfall device; therefore, on one hand, the invention provides a brand-new technical means for researching osmotic deformation generated by a soil layer in the rainfall process, karst collapse caused by the dominant flow and the like, also reproduces and reveals the cause mechanism of the karst collapse process, and provides a certain reference value for the prevention and prediction work of the karst collapse.
Description
Technical Field
The invention relates to the field of research on karst collapse technologies, in particular to an experimental method of a karst collapse experimental device based on an upper cover layer containing a dominant channel.
Background
In nature, soil is often perforated due to the interpenetration of plant roots, micro animals move to form channels and holes, dense dry shrinkage seams are generated in partial areas due to low water content of the soil, finger-shaped soil permeation channels are formed due to unstable wetting fronts, and the like, and the channels existing in the soil are called as dominant channels.
The process of water and solute passing through the porous medium through the dominant channel is called the preferential flow, and the preferential flow is used as the reflection form of the phenomenon that water moves in a certain part of the soil faster than other parts of the soil, so that the soil profile has irregular wetting degree. An important feature of the dominant flow is that when wet, the water content peak can quickly spread to a certain depth, while the migration rate around most of the matrix pore space is far beyond the range predicted by the Richards equation. Another important feature of the gravity flow is its own imbalance, i.e. the gravity flow acts as a flow path in which the infiltrated water does not have sufficient time to equilibrate with the rest of the soil matrix's slow migration, but is unbalanced.
For a karst area with an upper cover layer containing a dominant channel, in the rainfall process, rainwater gradually enters a deep karst through the upper cover layer, the dominant channel is used as a flow path, in the path, the sufficient time for infiltration of water is not kept in balance with other parts in the soil matrix which are slowly transported, at the moment, the rapid water flow can bring soil micro-particles into the deep karst channel, and the karst collapse phenomenon is accelerated under the combined action of the seepage force, the soil body gravity and a possible negative pressure effect.
Because the karst collapse has the characteristics of concealment in space, paroxysmal property in time and the like, great difficulty is brought to the research on the analysis of the cause mechanism of the karst collapse and the like, and the prevention, the control and the disaster reduction of the karst collapse are also one of the important scientific research problems at present. Therefore, the development of research on karst collapse is of great significance.
At present, the prediction and forecast of karst collapse is mainly a karst danger zoning method based on GIS technology, and the method mainly evaluates and analyzes influence factors of karst collapse, gives different weights to the influence factors, and realizes the grading of karst danger by applying the functions of GIS superposition analysis and the like. The prediction method has a good effect on forecasting and predicting karst collapse in a macroscopic region, but has large subjectivity on the aspects of selection of evaluation factors, weight assignment and the like, and can not make quantitative prediction and evaluation on the collapse range of a specific karst region, so that engineering management of karst disasters can not be effectively guided. A simulation experiment based on a similar theory brings possibility for researching analysis of a karst collapse microscopic cause mechanism and guides directions for quantitative prediction and evaluation of karst collapse.
At present, an existing karst collapse simulation device cannot effectively research the karst collapse type of an upper cover layer containing a dominant channel. Based on the above, research is now conducted on a karst collapse experimental device and an experimental method for an upper cover layer containing a dominant channel, and the collapse phenomenon can be effectively simulated through a physical model test.
Disclosure of Invention
The invention provides a karst collapse experimental device and method for an upper cover layer containing an advantageous channel, which can intuitively know the whole process of karst collapse of the upper cover layer containing the advantageous channel under a rainfall condition.
The technical scheme adopted by the invention is as follows: an experimental method based on a karst collapse experimental device with an upper cover layer containing dominant channels,
the karst collapse experimental device comprises a model box made of organic glass, a rainfall device 2 positioned above the model box, a water supply tank 3 positioned below the model box, a first variable water head tank 41 and a second variable water head tank 42 which are positioned on two sides of the model box and adjustable in height;
a non-contact video displacement measuring instrument 5 is erected right in front of the model box;
a partition plate 11 is horizontally arranged in the middle of the model box to divide the model box into an upper cover layer model box 12 and a lower karst cave model box 13; the partition board 11 is uniformly provided with water permeable holes, and the middle part of the partition board 11 is provided with more than two simulation holes 111 with adjustable hole areas; clay blocks 112 are uniformly paved in the overlay model box 12, an advantageous channel 113 and a soil pressure sensor 114 are embedded in each clay block 112, the advantageous channel 113 is a plastic film pipeline, and the soil pressure sensor 114 is connected with a soil pressure data acquisition device;
the side wall of the karst cave model box 13 is provided with pressure measuring holes, and each pressure measuring hole is connected with a water pressure data acquisition device through a water pressure sensor 131;
the outlet of the water supply tank 3 is communicated with three water outlet pipes, the first water outlet pipe is communicated with a first water changing head tank 41 through a first water pump 31, the second water outlet pipe is communicated with a second water changing head tank 42 through a second water pump 32, the third water outlet pipe is communicated with a rainfall device through a third water pump 33, and a water outlet valve 34 is arranged on the third water outlet pipe;
the first variable water head tank 41 is communicated with the cover layer model tank 12 through a first water injection pipeline 411, and the second variable water head tank 42 is communicated with the karst cave model tank 13 through a second water injection pipeline 421;
the experimental method specifically comprises the following steps:
step (1): the preparation of the dominant channel 113 is performed,
preparing a pair of circular iron rings and more than two iron wires, wherein two ends of each iron wire are respectively welded on the pair of circular iron rings to form a pipeline supporting framework, a plastic film layer is covered outside the pipeline supporting framework, and holes are uniformly pricked on the plastic film layer;
step (2): the preparation of the clay block 112 is carried out,
preparing a cubic model box, paving a metal mesh in the model box, filling clay into the model box, and embedding the soil pressure sensor 114 and the dominant channel 113 while filling so that two ports of the dominant channel 113 are positioned at different heights in the clay block 112;
compacting to form a clay block 112 after clay is filled in the model box, attaching a metal mesh to the outer surface of the clay block 112 to form a metal mesh layer, and forming more than two leakage holes on the metal mesh layer;
and (3): the clay blocks 112 are paved on the concrete block,
and (4): opening a simulation hole 111 on the partition board 11, and adjusting the opening position and the opening degree of the simulation hole 111;
and (5): the second water pump 32 is started and the height of the second water changing head box 42 is adjusted, so that the water supply tank 3 feeds water into the second water changing head box 42, the second water changing head box 42 feeds water into the karst cave model box 13 through the second water injection pipeline 421, the water level in the karst cave model box 13 gradually rises, and after a certain time, the karst cave model box 13 has a certain water level, namely, the simulated karst cave has a stable underground water level;
and (6): the first water pump 31 is turned on, the height of the first water changing head tank 41 is adjusted, so that the water supply tank 3 feeds water into the first water changing head tank 41, the first water changing head tank 41 feeds water into the overlay model tank 12 through the first water injection pipeline 411, the water level in the overlay model tank 12 gradually rises, and after a certain time, a certain water level is arranged in the overlay model tank 12, namely, the simulated overlay has a stable underground water level;
and (7): opening a third water pump 33 and controlling the opening degree of a water outlet valve 34 to enable the water supply tank 3 to supply water to the rainfall device, and uniformly leaking water downwards by the rainfall device, namely simulating rainfall on a karst area;
s1: the influence of rainfall and the size of the karst cave opening on karst collapse is researched,
the above steps (1), (2), (3), (5) and (6) are kept unchanged,
adjusting the opening position and the opening degree of the simulated hole 111 in the step (4), or adjusting the opening degree of the water outlet valve 34 in the step (7);
the soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument 5 respectively record and read information;
s2: the influence of the change of the underground water level and the size of the karst cave opening on the karst collapse is researched,
the above steps (1), (2), (3) and (6) remain unchanged, (deletion 7, no rainfall)
And (3) closing the third water pump 33 and screwing the water outlet valve 34, and adjusting the opening position and the opening degree of the simulated hole 111 in the step (4) or adjusting the height of the second variable water head tank 42 in the step (5) so that a vacuum negative pressure state is generated between the water level of the karst cave model tank 13 and the partition plate 11.
The soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument 5 respectively record and read information;
further, the rainfall device 2 comprises a rainfall box 21 and a rainfall guide pipe 22, the rainfall box 21 is horizontally arranged right above the model box through rainfall box brackets 23 arranged at four corners of the bottom surface, and water leakage holes are uniformly formed in the bottom surface of the rainfall box 21;
the rainfall guide pipe 22 is horizontally arranged at the upper part of the rainfall tank 21, and one end of the rainfall guide pipe 22 is communicated with a third water outlet pipe.
Further, the first variable water head tank 41 and the second variable water head tank 42 have the same structure and comprise a tank body and a tank body support 7 which is arranged at the bottom of the tank body and is adjustable in height, a vertical partition plate 71 which is vertical to the bottom surface of the tank body is arranged in the tank body, the height of the vertical partition plate 71 is lower than that of the tank body, and the tank body is divided into a water inlet tank and a water outlet tank by the vertical partition plate 71;
the water inlet tank of the first variable water head tank 41 is respectively communicated with the water supply tank 3 and the overlay model tank 12 through a first water pump 31 and a first water injection pipeline 411, and the water outlet tank of the first variable water head tank 41 is communicated with the water supply tank 3 through a pipeline;
the water inlet tank of the second water changing head tank 42 is respectively communicated with the water supply tank 3 and the karst cave model tank 13 through a second water pump 32 and a second water injection pipeline 421, and the water outlet tank of the second water changing head tank 42 is communicated with the water supply tank 3 through a pipeline.
Further, the middle part of the partition board 11 is provided with 3 simulation holes 111, and the 3 simulation holes 111 are uniformly formed along the length direction of the partition board 11;
each simulation hole 111 is provided with an adjusting mechanism 6, each adjusting mechanism 6 comprises a pair of circular baffles 61 and four arc-shaped plates 62, the circular baffles 61 are fixedly installed at intervals up and down, and a round hole with the same aperture is formed in the middle of each circular baffle corresponding to the simulation hole 111;
each arc-shaped plate 62 is movably arranged between the pair of circular baffles 61 through key groove matching;
when the corresponding ends of the four arc-shaped plates 62 are closed or separated, a pair of round holes on the pair of round baffles 61 are closed or opened, so that the corresponding simulation holes 111 are closed or opened.
The invention has the following beneficial technical effects:
(1) the karst collapse experimental device with the superiority channel in the overburden layer provided by the invention takes the karst collapse case with the superiority channel in the nature as a research object, can complete indoor experiments by means of the device, simulates different underground water supply and change conditions by a rainfall device and a variable water head box, and collects the experimental data of the whole process by a soil pressure, water pressure and displacement data acquisition device, so that the generation and development processes of dominant currents in the overburden layer under the rainfall condition can be clearly and intuitively displayed, the corrosion and deformation of a bottom plate under the overburden layer and the stable state of different time caused by water level fluctuation or change can be displayed, and the whole process of karst collapse development can be reproduced.
(2) According to the experimental method based on the karst collapse experimental device with the superior channel on the upper cover layer, when the experimental method is used, the clay blocks are prepared and paved, and the data acquisition device can collect and read data to a computer in real time by reasonably combining the influence factors through controlling the rainfall device, the variable water head tank and the simulation hole, so that the experimental data and the experimental rule have great reference values. The experimental data and the experimental rules are very favorable for analyzing and researching the essential relationship between different groundwater supplies and changes and karst collapse geological disasters, on one hand, good basic conditions are provided for deeply researching the collapse whole process of an overburden layer containing the dominant channel in a karst area, particularly, a novel technical means is provided for researching karst collapse caused by dominant flow, and on the other hand, the causative mechanism of the collapse whole process of the overburden layer containing the dominant channel under the mutual influence of a seepage field, a stress field and a displacement field can be reproduced and revealed. The invention can be implemented indoors, and has the advantages of visual phenomenon, short period, low cost, convenient movement and the like. The method also has the advantages of repeatability of experimental phenomena, reliable and real data, extremely high coincidence degree with the actual engineering and the like.
(3) The invention can provide a new idea for researchers in the field to explore the cause and mechanism of karst collapse in complex areas, solves the problems of quantification and visualization research in the field of karst collapse research to a certain extent, and provides a new method for prediction and forecast of karst collapse.
Drawings
FIG. 1 is a schematic structural diagram of a karst collapse experimental device based on an upper cover layer containing dominant channels.
FIG. 2 is a schematic view of the rainfall apparatus of the present invention.
FIG. 3 is a schematic structural view of a overlay model box of the present invention.
Fig. 4 is a diagram illustrating the alignment of the arc plates in the adjusting mechanism of the present invention.
Fig. 5 is a state diagram of the adjusting mechanism of the present invention in which the arc plate is unscrewed.
FIG. 6 is a schematic structural diagram of a cave model box of the present invention.
Fig. 7 is a schematic view showing a structure of a water service box according to the present invention.
FIG. 8 is a schematic view of the clay block of the present invention.
Fig. 9 is a view a-a of fig. 8.
Wherein: 11 partition plates, 111 simulation holes, 112 clay blocks, 113 dominant channels, 114 soil pressure sensors, 12 overlay model boxes, 13 karst cave model boxes, 131 water pressure sensors, 2 rainfall devices, 21 rainfall boxes, 22 rainfall conduits, 23 rainfall box supports, 3 water supply boxes, 31 first water pumps, 32 second water pumps, 33 third water pumps, 34 water outlet valves, 41 first water changing head boxes, 411 first water injection pipelines, 42 second water changing head boxes, 421 second water injection pipelines, 5 non-contact video displacement measuring instruments, 7 box body supports, 71 vertical partition plates, 6 adjusting mechanisms, 61 pairs of circular baffle plates and 62 arc plates.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the detailed description and specific examples, while indicating the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Examples
Referring to fig. 1, an experimental method based on a karst collapse experimental device with an upper cover layer containing dominant channels,
the karst collapse experimental device comprises a model box made of organic glass, a rainfall device 2 positioned above the model box, a water supply tank 3 positioned below the model box, a first variable water head tank 41 and a second variable water head tank 42 which are positioned on two sides of the model box and adjustable in height;
a non-contact video displacement measuring instrument 5 is erected right in front of the model box;
a partition plate 11 is horizontally arranged in the middle of the model box to divide the model box into an upper cover layer model box 12 and a lower karst cave model box 13; the partition board 11 is uniformly provided with water permeable holes, and the middle part of the partition board 11 is provided with more than two simulation holes 111 with adjustable hole areas; clay blocks 112 are uniformly paved in the overlay model box 12, an advantageous channel 113 and a soil pressure sensor 114 are embedded in each clay block 112, the advantageous channel 113 is a plastic film pipeline, and the soil pressure sensor 114 is connected with a soil pressure data acquisition device;
the first variable head tank 41 is connected to the cap model tank 12 through a first water injection pipe 411, and the second variable head tank 42 is connected to the karst cave model tank 13 through a second water injection pipe 421.
The first variable water head tank 41 and the second variable water head tank 42 are identical in structure and comprise a tank body and a tank body support 7 which is arranged at the bottom of the tank body and is adjustable in height, a vertical partition plate 71 which is vertical to the bottom surface of the tank body is arranged in the tank body, the height of the vertical partition plate 71 is lower than that of the tank body, and the tank body is divided into a water inlet tank and a water outlet tank by the vertical partition plate 71;
the water inlet tank of the first variable water head tank 41 is respectively communicated with the water supply tank 3 and the overlay model tank 12 through a first water pump 31 and a first water injection pipeline 411, and the water outlet tank of the first variable water head tank 41 is communicated with the water supply tank 3 through a pipeline;
the water inlet tank of the second water changing head tank 42 is respectively communicated with the water supply tank 3 and the karst cave model tank 13 through a second water pump 32 and a second water injection pipeline 421, and the water outlet tank of the second water changing head tank 42 is communicated with the water supply tank 3 through a pipeline.
Referring to fig. 2, the rainfall device 2 comprises a rainfall tank 21 and rainfall guide pipes 22, the rainfall tank 21 is horizontally arranged right above the model box through rainfall tank brackets 23 arranged at four corners of the bottom surface, and water leakage holes are uniformly formed in the bottom surface of the rainfall tank 21;
the rainfall guide pipe 22 is horizontally arranged at the upper part of the rainfall tank 21, and one end of the rainfall guide pipe 22 is communicated with a third water outlet pipe.
Referring to fig. 3, the middle of the partition plate 11 is provided with 3 simulation holes 111, and the 3 simulation holes 111 are uniformly formed along the length direction of the partition plate 11;
referring to fig. 4 and 5, each simulation hole 111 is provided with an adjusting mechanism 6, each adjusting mechanism 6 comprises a pair of circular baffles 61 and four arc-shaped plates 62, the pair of circular baffles 61 are fixedly installed at intervals up and down, and a round hole with the same aperture is formed in the middle of each circular baffle corresponding to the simulation hole 111;
each arc-shaped plate 62 is movably arranged between the pair of circular baffles 61 through key groove matching;
when the corresponding ends of the four arc-shaped plates 62 are closed or separated, a pair of round holes on the pair of round baffles 61 are closed or opened, so that the corresponding simulation holes 111 are closed or opened.
Referring to fig. 6, pressure measuring holes are formed in the side wall of the karst cave model box 13, and each pressure measuring hole is connected with a water pressure data acquisition device through a water pressure sensor 131; the bottom of the karst cave model box 13 is provided with a water drainage hole which is communicated with the water supply tank 3 through a pipeline.
Referring to fig. 7, the outlet of the water supply tank 3 is connected with three water outlet pipes, the first water outlet pipe is connected with a first variable water head tank 41 through a first water pump 31, the second water outlet pipe is connected with a second variable water head tank 42 through a second water pump 32, the third water outlet pipe is connected with a rainfall device through a third water pump 33, and a water outlet valve 34 is arranged on the third water outlet pipe;
referring to fig. 8 and 9, the soil pressure sensor 114 and the dominant channel 113 are buried in the clay block 112 such that two ports of the dominant channel 113 are located at different heights in the clay block 112;
the outer surface of the clay block 112 is attached with a metal mesh layer, and the metal mesh layer is provided with more than two leakage holes.
The experimental method specifically comprises the following steps:
step (1): the preparation of the dominant channel 113 is performed,
preparing a pair of circular iron rings and more than two iron wires, wherein two ends of each iron wire are respectively welded on the pair of circular iron rings to form a pipeline supporting framework, a plastic film layer is covered outside the pipeline supporting framework, and holes are uniformly pricked on the plastic film layer;
step (2): the preparation of the clay block 112 is carried out,
preparing a cubic model box, paving a metal mesh in the model box, filling clay into the model box, and embedding the soil pressure sensor 114 and the dominant channel 113 while filling so that two ports of the dominant channel 113 are positioned at different heights in the clay block 112;
compacting to form a clay block 112 after clay is filled in the model box, attaching a metal mesh to the outer surface of the clay block 112 to form a metal mesh layer, and forming more than two leakage holes on the metal mesh layer;
and (3): the clay blocks 112 are paved on the concrete block,
paving clay blocks 112 in the cap rock model box 12, so that the paving height of the clay blocks 112 is 0.5-1.5 times of the height of the karst cave model box 13;
and (4): opening a simulation hole 111 on the partition board 11, and adjusting the opening position and the opening degree of the simulation hole 111;
and (5): the second water pump 32 is started and the height of the second water changing head box 42 is adjusted, so that the water supply tank 3 feeds water into the second water changing head box 42, the second water changing head box 42 feeds water into the karst cave model box 13 through the second water injection pipeline 421, the water level in the karst cave model box 13 gradually rises, and after a certain time, the karst cave model box 13 has a certain water level, namely, the simulated karst cave has a stable underground water level;
and (6): the first water pump 31 is turned on, the height of the first water changing head tank 41 is adjusted, so that the water supply tank 3 feeds water into the first water changing head tank 41, the first water changing head tank 41 feeds water into the overlay model tank 12 through the first water injection pipeline 411, the water level in the overlay model tank 12 gradually rises, and after a certain time, a certain water level is arranged in the overlay model tank 12, namely, the simulated overlay has a stable underground water level;
and (7): opening a third water pump 33 and controlling the opening degree of a water outlet valve 34 to enable the water supply tank 3 to supply water to the rainfall device, and uniformly leaking water downwards by the rainfall device, namely simulating rainfall on a karst area;
s1: the influence of rainfall and the size of the karst cave opening on karst collapse is researched,
the above steps (1), (2), (3), (5) and (6) are kept unchanged,
adjusting the opening position and the opening degree of the simulated hole 111 in the step (4), or adjusting the opening degree of the water outlet valve 34 in the step (7);
the soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument 5 respectively record and read information;
s2: the influence of the change of the underground water level and the size of the karst cave opening on the karst collapse is researched,
the above steps (1), (2), (3) and (6) remain unchanged, (deletion 7, no rainfall)
And (3) closing the third water pump 33 and screwing the water outlet valve 34, and adjusting the opening position and the opening degree of the simulated hole 111 in the step (4) or adjusting the height of the second variable water head tank 42 in the step (5) so that a vacuum negative pressure state is generated between the water level of the karst cave model tank 13 and the partition plate 11.
The soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument 5 record and read information respectively.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (4)
1. An experimental method of an experimental device for karst collapse based on an upper cover layer containing a dominant channel is characterized in that:
the karst collapse experimental device comprises a model box made of organic glass, a rainfall device (2) positioned above the model box, a water supply box (3) positioned below the model box, a first variable water head box (41) and a second variable water head box (42), wherein the first variable water head box and the second variable water head box are positioned on two sides of the model box and are adjustable in height;
a non-contact video displacement measuring instrument (5) is erected right in front of the model box;
a partition plate (11) is horizontally arranged in the middle of the model box to divide the model box into an upper cover layer model box (12) and a lower karst cave model box (13); the water permeable holes are uniformly formed in the partition plate (11), and more than two simulation holes (111) with adjustable hole areas are formed in the middle of the partition plate (11); clay blocks (112) are uniformly paved in the overlay model box (12), an advantageous channel (113) and a soil pressure sensor (114) are buried in each clay block (112), the advantageous channel (113) is a plastic film pipeline, and the soil pressure sensor (114) is connected with a soil pressure data acquisition device;
the side wall of the karst cave model box (13) is provided with pressure measuring holes, and each pressure measuring hole is connected with a water pressure data acquisition device through a water pressure sensor (131);
an outlet of the water supply tank (3) is communicated with three water outlet pipes, the first water outlet pipe is communicated with a first water changing head tank (41) through a first water pump (31), the second water outlet pipe is communicated with a second water changing head tank (42) through a second water pump (32), the third water outlet pipe is communicated with a rainfall device through a third water pump (33), and a water outlet valve (34) is arranged on the third water outlet pipe;
the first variable water head tank (41) is communicated with the cover layer model tank (12) through a first water injection pipeline (411), and the second variable water head tank (42) is communicated with the karst cave model tank (13) through a second water injection pipeline (421);
the experimental method specifically comprises the following steps:
step (1): the preparation of the dominant channel (113) is carried out,
preparing a pair of circular iron rings and more than two iron wires, wherein two ends of each iron wire are respectively welded on the pair of circular iron rings to form a pipeline supporting framework, a plastic film layer is covered outside the pipeline supporting framework, and holes are uniformly pricked on the plastic film layer;
step (2): preparation of a clay block (112),
preparing a cubic model box, paving a metal mesh in the model box, filling clay into the model box, burying a soil pressure sensor (114) and an advantage channel (113) while filling, and enabling two ports of the advantage channel (113) to be located at different heights in a clay block (112);
compacting to form a clay block (112) after clay is filled in the model box, attaching a metal mesh to the outer surface of the clay block (112) to form a metal mesh layer, and forming more than two soil leaking holes in the metal mesh layer;
and (3): paving the clay blocks (112),
paving clay blocks (112) in the cap layer model box (12) to enable the paving height of the clay blocks (112) to be 0.5-1.5 times of the height of the karst cave model box (13);
and (4): opening a simulation hole (111) on the partition board (11), and adjusting the opening position and the opening degree of the simulation hole (111);
and (5): a second water pump (32) is started, the height of a second variable water head tank (42) is adjusted, so that the water supply tank (3) feeds water into the second variable water head tank (42), the second variable water head tank (42) feeds water into the karst cave model tank (13) through a second water injection pipeline (421), the water level in the karst cave model tank (13) gradually rises, and after a certain time, a certain water level is arranged in the karst cave model tank (13), namely, the simulated karst cave has a stable underground water level;
and (6): opening a first water pump (31) and adjusting the height of a first water changing head tank (41) to enable a water supply tank (3) to feed water into the first water changing head tank (41), enabling the first water changing head tank (41) to feed water into a overlay model tank (12) through a first water injection pipeline (411), enabling the water level in the overlay model tank (12) to gradually rise, and after a certain time, enabling the interior of the overlay model tank (12) to have a certain water level, namely simulating that an upper overlay has a stable underground water level;
and (7): opening a third water pump (33) and controlling the opening degree of a water outlet valve (34) to enable the water supply tank (3) to supply water to the rainfall device, and uniformly leaking water downwards by the rainfall device, namely simulating rainfall on a karst area;
s1: the influence of rainfall and the size of the karst cave opening on karst collapse is researched,
the above steps (1), (2), (3), (5) and (6) are kept unchanged,
adjusting the opening position and the opening degree of the simulated hole (111) in the step (4), or adjusting the opening degree of the water outlet valve (34) in the step (7);
at the moment, the soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument (5) respectively record and read information;
s2: the influence of the change of the underground water level and the size of the karst cave opening on the karst collapse is researched,
the above steps (1), (2), (3) and (6) are kept unchanged,
closing the third water pump (33) and screwing the water outlet valve (34), and adjusting the opening position and the opening degree of the simulated hole (111) in the step (4) or adjusting the height of the second variable water head tank (42) in the step (5) to enable a vacuum negative pressure state to be generated between the water level of the karst cave model tank (13) and the partition plate (11);
at the moment, the soil pressure data acquisition device, the water pressure data acquisition device and the non-contact video displacement measuring instrument (5) respectively record and read information.
2. The experimental method of the experimental device for the karst collapse based on the upper covering layer containing the dominant channel as claimed in claim 1, wherein: the rainfall device (2) comprises a rainfall box (21) and rainfall guide pipes (22), the rainfall box (21) is horizontally arranged right above the model box through rainfall box brackets (23) arranged at four corners of the bottom surface, and water leakage holes are uniformly formed in the bottom surface of the rainfall box (21);
the rainfall guide pipe (22) is horizontally arranged at the upper part of the rainfall box (21), and one end of the rainfall guide pipe (22) is communicated with the third water outlet pipe.
3. The experimental method of the experimental device for the karst collapse based on the overburden including the dominant channel as claimed in claim 1, wherein: the first water-changing head tank (41) and the second water-changing head tank (42) are identical in structure and comprise a tank body and a tank body support (7) which is arranged at the bottom of the tank body and is adjustable in height, a vertical partition plate (71) which is vertical to the bottom surface of the tank body is arranged in the tank body, the height of the vertical partition plate (71) is lower than that of the tank body, and the tank body is divided into a water inlet tank and a water outlet tank by the vertical partition plate (71);
the water inlet tank of the first water changing head tank (41) is respectively communicated with the water supply tank (3) and the overlay model tank (12) through a first water pump (31) and a first water injection pipeline (411), and the water outlet tank of the first water changing head tank (41) is communicated with the water supply tank (3) through a pipeline;
and a water inlet tank of the second water changing head tank (42) is respectively communicated with the water supply tank (3) and the karst cave model tank (13) through a second water pump (32) and a second water injection pipeline (421), and a water outlet tank of the second water changing head tank (42) is communicated with the water supply tank (3) through a pipeline.
4. The experimental method of the experimental device for the karst collapse based on the overburden including the dominant channel as claimed in claim 1, wherein: the middle part of the partition board (11) is provided with 3 simulation holes (111), and the 3 simulation holes (111) are uniformly formed along the length direction of the partition board (11);
each simulation hole (111) is provided with an adjusting mechanism (6), each adjusting mechanism (6) comprises a pair of circular baffles (61) and four arc-shaped plates (62), the pair of circular baffles (61) are fixedly installed at intervals up and down, and the middle of each circular baffle, corresponding to the simulation hole (111), is provided with a round hole with the same aperture;
each arc-shaped plate (62) is movably arranged between the pair of circular baffles (61) in a matched manner through a key slot;
when the corresponding ends of the four arc-shaped plates (62) are involutory or separated, a pair of round holes on the pair of round baffles (61) is closed or opened, so that the corresponding simulation holes (111) are closed or opened.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114563263A (en) * | 2022-03-29 | 2022-05-31 | 中国地质大学（武汉） | Device and method for simulating engineering impact induced karst collapse in seepage environment |
| CN117388466A (en) * | 2023-10-31 | 2024-01-12 | 山东科技大学 | Experimental device for simulating karst ground subsidence formation and evolution |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109036065A (en) * | 2018-08-20 | 2018-12-18 | 成都理工大学 | Single layer waterproofing type cap rock is collapsed to because of experimental provision |
| AU2020103048A4 (en) * | 2019-12-16 | 2020-12-24 | Guilin University Of Technology | Anti-floating simulation device of subways in karst areas |
-
2021
- 2021-12-20 CN CN202111559435.6A patent/CN114241876B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109036065A (en) * | 2018-08-20 | 2018-12-18 | 成都理工大学 | Single layer waterproofing type cap rock is collapsed to because of experimental provision |
| AU2020103048A4 (en) * | 2019-12-16 | 2020-12-24 | Guilin University Of Technology | Anti-floating simulation device of subways in karst areas |
Non-Patent Citations (1)
| Title |
|---|
| 吴庆华;张伟;刘煜;崔皓东;: "基于物理模型试验的岩溶塌陷定量研究", 长江科学院院报, no. 03 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114563263A (en) * | 2022-03-29 | 2022-05-31 | 中国地质大学（武汉） | Device and method for simulating engineering impact induced karst collapse in seepage environment |
| CN114563263B (en) * | 2022-03-29 | 2023-09-05 | 中国地质大学（武汉） | Experimental method for simulating engineering impact induced karst collapse device in seepage environment |
| CN117388466A (en) * | 2023-10-31 | 2024-01-12 | 山东科技大学 | Experimental device for simulating karst ground subsidence formation and evolution |
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