2018 results about "Karst" patented technology

The invention provides a fissure-cave type carbonate-reservoir reservoir body modeling method, and belongs to the field of carbonate reservoir exploitation geology. The method comprises the steps of (1) distinguishing karst cave reservoir body development segment in a single well; (2) building karst zone models along the vertical direction, building ancient landform unit distribution models in a plane; (3) respectively imitating three-dimensional distribution of the karst cave reservoir body in different karst zones and different ancient landform units, obtaining a three-dimensional distribution model of the karst cave reservoir body of a modeling target stratum; (4) counting development occurrence of a fissure reservoir body and single-well fissure development density; and (5) under control of a fault, building a three-dimensional discrete distribution model of the fissure reservoir body. According to the fissure-cave type carbonate-reservoir reservoir body modeling method, accuracy of the class of reservoir modeling is improved, a true condition of the reservoir is approached in a more objective mode, and important practical significance is provided for exploitation of the reservoir.

The invention provides a physical simulation experimental device for oil and gas charging of a fracture-cave carbonate reservoir. The physical simulation experiment device comprises a fracture-cave model, an experiment table with a window, surrounding rock and a camera shooting and monitoring system, wherein the fracture-cave model comprises simulation caves in different sizes and simulation fractures in different sizes, and the simulation caves are communicated through the simulation fractures; the fracture-cave model is arranged in the experiment table with the window, and the simulation caves in at least one side of the fracture-cave model are visible through the window of the experiment table; the surrounding rock surrounds the fracture-cave model to form the fracture-cave carbonate reservoir in a simulating manner; and the camera shooting and monitoring system is used for detecting and adjusting changes of both the flow rate and pressure in the charging process and recording images, displayed in the window, of the fractures and the caves in the charging process. The invention further provides a physical simulation method for oil and gas charging of the fracture-cave carbonate reservoir, and the physical simulation method employs the experimental device. According to the physical simulation method and the physical simulation experimental device for oil and gas charging of the fracture-cave carbonate reservoir, an oil-gas-water distribution rule can be obtained according to such parameters as karst, fractures, crude oil density and oil-gas-water distribution.

The present invention provides a physical simulation experiment device of fracture-cavity carbonate reservoir hydrocarbon charge. The experiment device comprises a fracture-cavity model, an experiment stand with windows, a wall rock and a camera monitoring system; the fracture-cavity model comprises simulation caves in different sizes and simulation fractures in different sizes; the simulation caves are connected to one another via the simulation fractures; the fracture-cavity model is arranged inside the experiment stand with windows, and the simulation caves of at least one side of the fracture-cavity model are visual through the windows of the experiment stand; a surrounding of the wall rock is arranged around the fracture-cavity model to simulate a formation of fracture-cavity carbonate reservoir; the camera monitoring system is used for measuring and adjusting changes in flow rate and pressure in a charge process, and recording an image of fracture and cave in the charge process displayed in the windows. The present invention further provides a physical simulation method of fracture-cavity carbonate reservoir hydrocarbon charge, which uses the above-mentioned experiment device. The present invention can obtain regularities of distribution of oil, gas and water through parameters such as karsts, fractures, density of cruel oil, and oil, gas and water distribution and the like.

The invention provides a method for identifying and interpreting carbonate rock ancient karst reservoir layer three-dimensional structure. Steps of identifying a single well cave preferably comprise that: according to a cave growing segment with definite rock core and electric imaging well logging information, conventional well logging response characteristics of the cave growing segment are summarized; cave sensitive well logging parameters are preferably selected via a well logging parameter intersection method, and an identification graph plate is established; a multi-parameter normalization weighting method is utilized to establish a cave identification function; steps of identifying an inter-well cave preferably comprise that: a synthetic seismic recording method is utilized toward each single well to calibrate a cave interpreting result of a depth domain to an acoustic inversion data volume of a time domain; then threshold values of a cave segment and a non-cave segment are confirmed so that the inter-well cave is effectively identified; continuous tracking is performed along the middle of caves which are large in scale and great in continuity so that a three-dimensional tracking layer is obtained, an average value of 2ms acoustic save impedance around the tracking layer is computed, and thus a three-dimensional space growing position of an ancient karst reservoir layer is obtained.

The invention discloses a construction treatment method of a filling karst tunnel. The construction treatment method comprises the following steps that (a), a karst development control factor and a development principle are sought; (b), karst detecting is conducted for advance geology forecast; (c), analysis of influence of filling karst on stability of tunnel surrounding rocks is conducted; and (d), filling karst treatment is conducted. According to the construction treatment method of the filling karst tunnel, filling karst advance geology forecast, pre-reinforcement measures and the normal construction technical process of the tunnel are organically combined, and the safety risks of filling karst section tunnel construction are reduced or avoided by sufficiently using the means and methods such as advance geology forecast and pre-reinforcement. The construction treatment method is applied to tunnel filling karst construction of highways and railways, and meanwhile, the construction treatment method has imitative and referential significances on construction of the railways, the highways, municipal administrations and hydraulic tunnels (caves) with similar geological conditions.

The invention provides a method for establishing a large-sized karst cave reservoir body distribution model of a fractured-vuggy carbonate rock reservoir, and belongs to the field of three-dimensional geologic modeling of carbonate rock reservoirs. The method comprises the following steps of: (1) identifying a large-sized karst cave reservoir body development section on a single well, wherein the large-sized karst cave reservoir body development section is an interval with large-sized karst cave reservoir bodies; (2) establishing a karst zone model in a perpendicular direction, and establishing a palaeogeomorphological unit distribution model on a plane; and (3) simulating the three-dimensional distribution of the large-sized karst cave reservoir bodies in different karst zones and palaeogeomorphological units respectively to obtain a three-dimensional large-sized karst cave reservoir body distribution model of a modeling target stratum. The control effect of a karst development mode on the distribution of the large-sized karst cave reservoir bodies is taken into a full account, the constraints of geological laws are enhanced in a modeling process, and the modeling accuracy of the large-sized karst cave reservoir bodies of carbonate rocks is improved.

The invention relates to a construction technology for allowing a tunnel to pass through a karst cave, and in particular relates to a construction technology for allowing a tunnel to pass through an ultra-large karst cave. The technology at least comprises the following steps of: 1) performing simple bridge treatment on the underground part of the karst cave; 2) performing primary support, namelyarranging a support wall at one side of the karst cave; 3) forming parallel guide holes; 4) performing bottom treatment; 5) treating the tunnel hole body at the inlet section of the karst cave; 6) filling C25 early strength sprayed concrete within 1 meter at the top of the support wall, and arranging phi 50 small grouting conduits with the lengths of 3 meters in the concrete, wherein the distancebetween the small conduits is 1.5 meters; 7) supporting the arch part and the side wall surrounding rock of the karst cave by adopting phi 22 cartridge anchor rods arranged in a plum blossom shape and at a distance of 150cm*150cm, hanging phi6 reinforcing meshes at a distance of 15cm*15cm, and spraying C25 early strength concrete with the thickness of 15 centimeters; 8) treating the accumulation of the karst cave; and 9) monitoring and measuring when the tunnel passes through the ultra-large karst cave. The construction technology for allowing the tunnel to pass through the ultra-large karst cave is simple in process, convenient for construction, low in cost, scientific, effective, energy-saving and environmentally-friendly.

The invention relates to a karst area drilling cast-in-place pile structure which is characterized in that a cast-in-place pile, a bag grouting body and a prestress anchor cable are included; an original karst portion is backfilled with a clay and rubble mixture; the top of the cast-in-place pile is provided with a pile top expansion pile body, and a karst position is provided with the bag grouting body; a squeezing reinforcement cage is arranged in the bag grouting body; prestress anchor cable holes are formed around the cast-in-place pile, and the top of the prestress anchor cable penetrates through the pile top expansion pile body. The karst area drilling cast-in-place pile structure has the advantages of being quick in construction speed, low in cost and the like. Besides, the bearing capacity of a single pile is enhanced by changing the action mechanism of the cast-in-place pile, and the aim of solidifying a foundation is achieved. The invention further discloses a construction method of the karst area drilling cast-in-place pile structure.

The invention discloses a karst grouting reinforcement water-stop constructing method, which is to construct according to sizes of karst caves by adopting a principle of from big to small regarding a certain area, construct by adopting a principle of from outside to inside for the karst caves with the same size, and construct by adopting a principle of from the bottom to the top in a vertical direction. On the basis of the construction principles, the method comprises the following steps of: (1) forming grouting holes by adopting a core drill; (2) forming construction exhaust and drainage pressure relief holes; (3) inserting grouting pipes into the grouting holes, wherein the grouting pipes comprise steel pipes, grouting shock pipes and sleeve valve pipes; (4) cleaning the holes, wherein when the step (3) is completed, the grouting pipes are cleaned with clean water; (5) grouting; and (6) drawing out the grouting pipes after the grouting is completed, and blocking the grouting holes with cement mortar or concrete. By adopting the constructing method, the pertinence to karst caves is strong, the grouting quantity is small, the engineering work amount is small, the cost is low, and the effect of filling and reinforcing is good.

The invention discloses a drilling pile drilling construction method of a bead-type karst area, wherein a drilling pile penetrates through an underground river karst cave from top to bottom. The method includes the steps of (1) measuring and sampling, (2) lowering and fixing a steel casing, and (3) drilling, wherein a percussion drill is used, drilling is carried out from top to bottom through the lowered steel casing until the percussion drill reaches a designed depth, and in the drilling process, the wall is protected through slurry; in the drilling process, when the percussion drill drills the underground river karst cave from top to bottom, the underground river karst cave is firstly processed, and then the percussion drill is used for drilling downwards; when the underground river karst cave is processed, the process is as follows: drilling of an inner protection casing installation hole, lowering of an inner protection casing, continuous drilling and plugging of a water source. The method is simple in step, reasonable in design, low in investment cost, convenient to achieve and good in construction effect, the drilling construction process of a drilling pile penetrating through the underground river karst cave can be easily, conveniently and quickly completed, cost is low and quality is high.

The invention discloses a method for inter-planting forage grass in orchards at a karst rock desertification region, in particular a method for inter-planting leguminous forage grass and gramineous forage grass below fruit trees in the orchards, wherein the mixing weight ratio of the leguminous forage grass to the gramineous forage grass is (5-7):(3-5), and the seeding rate is 1.5-2.0 kg / mu. According to the method, the leguminous forage grass and the gramineous forage grass are selected and sowed in a mixed way according to the characteristics of high yield and low crude protein content of the gramineous forage grass and high crude protein content of the leguminous forage grass, so that the yield and the quality of the forage grass are improved, and the palatability of the forage grass and the absorption of livestock to the nutrients of the forage grass are enhanced; by performing mixed sowing on the leguminous forage grass and the gramineous forage grass according to a weight ratio of (5-7):(3-5) under fruit trees, the coverage ratio of land vegetation of the orchards is increased and water and soil loss is greatly reduced; and meanwhile, the soil fertility of the orchards can also be increased, the environment of the orchards is improved, the productivity of land is improved, and the aims of increasing the yield of fruit trees and the yield of the forage grass are fulfilled.

A whole-process simulation experiment system has: a visualized model system with test samples and serving as a bearing device for the simulation of whole-process seepage of filling-type karst; a controllable support system supporting a visualized model box and controlling fluid seepage direction in the box by changing its inclination angle; a servo loading system controlling water pressure in the test process and providing four different loading modes for the box; a high-speed camera system recording water flow and particle motion in a transparent seepage model box in the seepage failure process; a comprehensive data measuring system monitoring and recording the change rules of factors including but not limited to seepage pressure, seepage amount and sand gushing amount in the seepage failure process; and an information analysis and feedback system recording and analyzing the seepage process and the whole seepage failure process in real time to achieve data processing and feedback.

The invention relates to a karst cave type foundation stability estimation method, in particular to a measurement method of karst cave type foundation collapse risks. The measurement method mainly solves the problem that because comprehensive prediction methods for the karst cave type foundation stability are immature in the prior art and judgment models are established on the basis of different angles, the reliability of influence factors is greatly lowered. According to the specific scheme, the relation between vertical stress of overlaying soil on karst caves and limit vertical stress of the overlaying soil on the karst caves is derived and established according to the karst collapse mechanism of karst cave type foundations, stability loss risk estimation parameters for determining karst cave type foundation collapse are proposed, and the one-to-one corresponding relation between the karst cave type foundation stability loss risk estimation parameters and stability factors is established. The measurement method has the advantages of having clear stability criteria, being simple and practical and having high practicality value for effective prediction, prevention and control of karst cave type foundation collapse.

The invention provides a method for establishing a solution vug reservoir body distribution model of a fractured-vuggy carbonate rock reservoir, and belongs to the field of three-dimensional geologic modeling of carbonate rock reservoirs. The solution vug reservoir body distribution model of the fractured-vuggy carbonate rock reservoir of a modeling target stratum is established according to the characteristic that the development of solution vug reservoir bodies is controlled by large-sized karst cave distribution. Great differences in reservoir body space scales between the solution vug reservoir bodies and other reservoir bodies such as large-sized karst cave reservoir bodies are taken into account, and a solution vug reservoir body model is independently established, so that the three-dimensional distribution of the solution vug reservoir bodies can be described more finely; and moreover, a relationship between distances to large-sized karst caves and quantitative development probabilities of the solution vug reservoir bodies is established, the distribution rules of the solution vug reservoir bodies are reflected more objectively by the model established under the constriction of the relationship, a more objective and more real three-dimensional solution vug reservoir body distribution model is established, and the accuracy of a geologic model of the fractured-vuggy carbonate rock reservoir is improved.

Shallow drilling hazards (44), such as karsts, caves, voids and unconsolidated discontinuities, that can pose significant risks to exploration and development well drilling operations are detected employing seismic refraction data on which a series of attribute analyses are performed, the resulting data being further processed to provide a three-dimensional visualization. Refracted wave raypaths (40, 46, 48) are highly distorted by encountering a karst feature with the occurrence of backscattering absorption. The resultant energy recorded at the surface receivers (52) is significantly reduced as compared to refracted waves recorded by other receivers (50) where no karsting is present. Multiple refractors are subjected to a relatively simple and rapid processing using commercially available software to track these differences and to map them in the near surface to improve the siting of wells and to alert drilling engineers and crews to the possibility of encountering the hazard.

The invention relates to natural gas exploitation technology, in particular to a well spacing method for a karst carbonate reservoir. The method comprises the following steps of: selecting an upper isochronous surface and a lower isochronous surface close to end time of caledonian tectogenesis and starting time of Hercynian tectogenesis; reflecting an ancient landform which is high in the west and low in the east and partially develops residual hills and depressions by using a contour diagram; acquiring seismic data; determining a low relief structure form and an evolution process according to inversion section and cross-well seismic data; dividing sedimentary facies of the carbonate reservoir into sedimentary subfacies and sedimentary microfacies; dividing favorable sedimentary microfacies; determining that the reservoir of each well area is communicated by means of yield of the conventional production well and pressure measurement data; and dividing a favorable well spacing area andplacing well at the area with reservoir thickness of more than 20m. The method has the advantages of rational well spacing, measured drilling ratio of well spacing gas reservoir of 100 percent, drilling success rate of 82 percent and capability of obtaining an industrial gas flow from a lower-palaeozoic gas reservoir section and saving capital.

The invention belongs to the technical field of super-long pile construction of engineering construction, and discloses a large-diameter super-long pile construction method in the karst area through full-casing pipe full rotating and rotary drilling. The method comprises the steps of selecting the types of full casing pipes, rotating the installing casing pipes by 360 degrees, pressing the first casing pipe, checking the perpendicularity, alternately using a punching grab hand and an impact hammer, grabbing land rocks through a grab bucket, drilling the casing pipes to the hole bottoms, measuring the hole depth, carrying out hole cleaning for the first time, installing manufactured reinforcement cages, carrying out butt joint on the reinforcement cages, installing manufactured guide pipes subjected to pressure-bearing tests and sealing tests, arranging water isolation bolts, carrying out hole cleaning for the second time, pouring manufactured concrete, measuring the height of the concrete, pulling the guide pipes and the casing pipes sequentially, verifying the perpendicularity and pulling the casing pipes before initial setting of the concrete. According to the method, the pile driving efficiency of projects is improved, and the total cost of the projects is lowered.

The invention belongs to the technical field of tunnel traversing extra-large karst cave construction, aims at solving the problem that an existing foundation construction method cannot be suitable for extra-large karst caves and provides an extra-large karst cave bottom treatment construction method. A pipe-following drilling process is adopted to synchronously follow a sleeve in the drilling process, the sleeve penetrates through an easily-collapsed stratum to partition the easily-collapsed stratum, the pipe-following drilling is stopped at the karst cave position, then fine aggregate concrete is adopted for backfill, and continuous drilling is completed after backfill is completed. Working efficiency is greatly improved, cost is reduced, and time is saved. The pipe-following drilling process is effective compared with construction of the easily-collapsed stratum and can be universally applied to slope protection under similar geological conditions and foundation base reinforcement treatment projects. A full-automatic casting recording instrument is adopted for recoding, treatment is timely performed in an intermittent or slurry mixture ratio adjusting mode if one-single casting amount is too large or no pressure exists for long time, meanwhile the requirements for casting pressure and casting amount are ensured, and casting reinforcement effect is ensured.

The invention discloses a karst geology rotary-drilling bored concrete pile hole forming process which includes the steps of 1, leveling a field; 2, paying off at a pile foundation; 3, setting a rotary drilling machine in place; 4, embedding a pile casing; 5, preparing mud stabilizing liquid and filling the mud stabilizing liquid into the pile casing; 6, forming holes by means of rotary drilling (with requirements of reducing drilling speed when drilling in karst caves or half rocks, otherwise, drilling to reach designed elevation ); 7, performing primary cleaning of holes and hole depth checking; 8, mounting a reinforced cage and a conduit; 9, performing secondary cleaning through air-lift reverse circulation; 10, pouring underwater concrete (while preparing extra 30-40 cubic meters of concrete with consideration of karst caves so as to prevent pile scrap caused by breakdown of the karst caves and sharp sinking of concrete); and 11, forming a pile and removing the pile casing.

The invention discloses an injection-production well pattern construction method suitable for carbonate fractured-cave reservoirs and relates to the technical field of oil and gas reservoir development. The method includes the steps that the types of carbonate fractured-cave structures are recognized; according to different types, the fractured-cave structures are depicted; the correlation of communicated fractured cave structures in fractured caves is analyzed, and a fractured cave reservoir body communicated structure is built; used reserves and control reserves of fractured cave reservoir bodies are calculated and marked; an injection-production well pattern mode corresponding to a Karst geological backgrounds of the carbonate fractured-cave reservoirs is constructed; a well pattern injection production relation of the carbonate fractured-cave reservoirs is built and optimized. The method solves the problems that a conventional injection-production well pattern construction method is not applicable to development of the carbonate fractured-cave reservoirs and an existing irregular well pattern deployment method is not mature or referential. The new injection-production well pattern construction method suitable for the fractured-cave reservoirs is provided and improves the recovery efficiency of the fractured-cave reservoirs.

The invention relates to a method for treating a tunnel passing through underground river karst hall. The method comprises the following steps of: a, searching for the position of the underground river karst hall and analyzing geological features; b, excavating a service gallery to reveal the underground river karst hall; c, mechanically clearing rock mass with potential safety hazard, clearing accumulation bodies in the underground river hall to an appropriate position higher than the top of a tunnel, forming a diversion channel, arranging a retaining dam at an appropriate upstream position of an underground river and transferring open water current of the underground river to the diversion channel for draining; d, arranging a reinforced concrete bottom plate in the underground river hall, drilling holes downwards on the bottom plate and grouting to reinforce a karst cave accumulation body; and e, undermining the tunnel. The underground river karst hall is revealed in a way of arranging the service gallery and drainage, grouting and reinforcement are directly performed on the underground river, so that a passive mode is replaced by an active mode, an existing water path of the underground river is kept and the safety and reliability of tunnel construction and operation are ensured.

Shallow drilling hazards (44), such as karsts, caves, voids and unconsolidated discontinuities, that can pose significant risks to exploration and development well drilling operations are detected employing seismic refraction data on which a series of attribute analyses are performed, the resulting data being further processed to provide a three-dimensional visualization. Refracted wave raypaths (40, 46, 48) are highly distorted by encountering a karst feature with the occurrence of backscattering absorption. The resultant energy recorded at the surface receivers (52) is significantly reduced as compared to refracted waves recorded by other receivers (50) where no karsting is present. Multiple refractors are subjected to a relatively simple and rapid processing using commercially available software to track these differences and to map them in the near surface to improve the siting of wells and to alert drilling engineers and crews to the possibility of encountering the hazard.

The invention discloses a processing method for a high-pressure water-enriched filling karst cavity, comprising the steps of finding out a filling karst cavity through a former geologic predicting report, analyzing the karst characteristic of the found filling karst cavity, locking the proximity borderlines of the filling karst cavity according to the analysis result of the karst characteristic ofthe filling karst cavity, opening the filling karst cavity at the proximity borderlines of the filling karst cavity and releasing the water-soil pressure in the filling karst cavity. The technical scheme of the invention can effectively avoid the phenomena of water-inrush and soil-inrush generated in the filling karst cavity by directly decreasing the pressure of the filling karst cavity, and improving the safety and reliability during the tunneling and the tunnel operation.

The invention discloses a pile bottom cave sonar detection device and method. The signal output end of a three-dimensional electronic compass it connected with the compass signal input end of a single-chip microcomputer. The signal input end of a sonar stress wave driving module is connected with the signal output end of the single-chip microcomputer. The stress wave driving signal output end of the sonar stress wave driving module is connected with a sonar stress wave transmitter. A sonar stress wave receiving sensor is connected with the sonar signal input end of the single-chip microcomputer through a sonar stress wave signal processing module. The communication end of the single-chip microcomputer is connected with an on-site host through a communication cable. A sonar detection probe is perpendicular to the bottom of a pile. The pile bottom cave sonar detection device and method, which are provided by the invention, can carry out detailed karst cave or weak rock detection on an area below the pile bottom, and can accurately determine whether a karst cave or weak rock is in a pile bottom detection range, wherein the karst cave or the weak rock influences the bearing capacity of the pile bottom.

The invention relates to a foundation processing method, in particular to a foundation integrated processing construction method of a cover type karst area. The method comprises the following steps of: evacuating earth moving machinery when a foundation pit is excavated until a limestone formation is exposed in a large area; basically exposing rocks of the bottom of the foundation pit after excavating, wherein rock buds are exposed from a foundation base, and the storage quantity of damic earth among the rock buds does not influence the next procedure construction; adopting weakened loose blasting operation, aiming at solution cracks, intermountain gulches and locally crushing bedrocks, and mechanically crushing and clearing; adopting a complex geophysical prospecting technological means that a high-density resistivity method is combined with a geological radar, arranging a high-density electrical geophysical prospecting wire in a construction site according to an arrangement rule, meanwhile, arranging a detailed exploratory hole in a building planning position, and mechanically picking the solution cracks, the intermountain gulches and the locally crushing bedrocks; adopting sleeve valve cement flour and coal ash slurry injecting constriction and cement flour and coal ash slurry filling constriction by a solution cavity slurry-injection method; and filling and casting concrete. The invention can quicken a work progress and can save construction cost compared with other foundation processing modes.

The invention discloses a construction method of pile foundations of bridge karst caves in a karst area. The construction method comprises the following steps: punching and karst cave treatment are conducted, and punching and karst cave treatment are carried out repeatedly till holes are formed finally; and karst cave treatment specifically comprises the steps of type identification and treating methods, wherein type identification is that before drilling starting, in the process of drilling and in the process of pouring, the types of the karst caves are judged according to the vertical depthand whether fillers exist or not, and the treating methods comprise pretreatment before construction, treatment during drilling and treatment in the process of concrete pouring. The different treatingmethods are adopted for the different karst caves, thus construction of the pile foundations of the karst caves is safer and more effective, and the purposes of accelerating the hole forming progress, ensuring the pile forming quality and saving the construction cost are achieved.

The invention relates to a three-dimensional single-well gas injection oil replacement simulation experiment device for a fracture-cavity reservoir. The experiment device comprises a gas injection system, a fracture-cavity simulation system and an image collecting and information processing system, wherein the fracture-cavity simulation system is communicated with the gas injection system, and the image collecting and information processing system is used for collecting, transmitting and processing image and data information of the fracture-cavity simulation system. The fracture-cavity simulation system comprises a plurality of karst cave models, a plurality of fracture models and a plurality of wellbore models, wherein the fracture models are used for allowing every two adjacent karst cave models to be connected in series; the wellbore models are communicated with the gas injection system, all the karst cave models and all the fracture models. The image collecting and information processing system comprises a plurality of particle imaging test modules and image collecting modules, wherein the particle imaging test modules are arranged in all the karst cave models respectively, and the image collecting modules are arranged on the periphery of the fracture-cavity simulation system. The experiment device can accurately and visually monitor the migration speed, pressure and time, in the gravitational differentiation process, of the three phases comprising oil, gas and water in karst caves, fractures and wellbores in real time, and therefore the experiment device can be widely used in research, development and production of oil and gas fields.

The invention relates to a tunnel protection structure crossing a high-top and deep-bottom karst cave, which is arranged in the high-top and deep-bottom karst cave and comprises a main body structure of a tunnel, a protective cover, a foundation protective cover, a foundation arc structure of the protective cover and a supporting arch bridge of the tunnel. The tunnel protection structure crossing a high-top and deep-bottom karst cave is characterized in that the protective cover is arranged above the main body structure of the tunnel; the foundation arc structure of the protective cover is arranged at the foundation root of the protective cover; and the foundation arc structure of the protective cover spans over the karst cave; a tunnel bottom arc structure spanning over the karst cave is arranged below the main body structure of the tunnel; and the tunnel bottom arc structure supports the main body structure of the tunnel. , by the tunnel protection structure crossing a high-top and deep-bottom karst cave, a high-top and deep-bottom semi-filling karst cave with short longitudinal distance can be protected, the purpose of minimizing serious damage of dangerous falling rocks to projects is realized, and the safety and the reliability of the construction and the long-term operation of the main body structure of the tunnel can be ensured.