Triaxial apparatus rock mechanical strength test auxiliary device for realizing coupling of confining pressure, water immersion and seepage

Abstract

The triaxial apparatus rock mechanical strength test auxiliary device provided by the invention realizes confining pressure, water immersion and seepage coupling, and overcomes the technical defect that a rock mechanical strength test result does not conform to an actual condition under a dry-wet cycle condition. The water sump, the water flow control equipment, the system water pipe, the two-dimensional water flow control device, the flow dividing device and the triaxial apparatus water tank run mutually to jointly realize confining pressure, water immersion and seepage coupling test conditions, and the rock mechanical strength under the test conditions can be accurately obtained in real time in cooperation with a conventional triaxial apparatus rock mechanical strength test device. The auxiliary device can realize different water solution conditions such as pH change, ion concentration change, water source change, water temperature change and the like, and can realize different seepage environment conditions such as water velocity change, water impact angle change, water pressure change and the like. The method has important theoretical value and practical significance for revealing the instability mechanism research of the influence of reservoir water level fluctuation on the high-steep dangerous rock in the reservoir area.

Description

Technical Field

[0001] The present invention belongs to the technical field of rock mechanics testing, and specifically relates to a testing auxiliary device suitable for testing the influence of water seepage in a reservoir area formed by a water conservancy project on the rock mechanics strength of a high-steep and dangerous rock wading base formed by the slopes on both sides of a canyon section. The device can assist a triaxial instrument in jointly realizing rock mechanics strength testing conditions of confining pressure, immersion and seepage coupling. Background Art

[0002] Globally, dangerous rock collapse geological disasters, that is, the instability of high-steep dangerous rocks, often occur in mountainous areas. Compared with other types of geological disasters, such as landslides and debris flows, dangerous rock collapse is complex, hidden, sudden and highly destructive, making it extremely difficult to monitor, warn and prevent risks of high-steep dangerous rocks. The existence of high-steep dangerous rocks poses a huge threat to infrastructure construction and safe operation and maintenance.

[0003] The disaster-causing factors of the instability of high-steep and dangerous rocks include many aspects, such as freeze-thaw cycles, earthquakes, natural rainfall, karst effects, stratum factors, river system cutting effects, reservoir water level drawdown and human engineering activities. With the construction of water conservancy hub projects in the areas where major river systems are located, a wide range of reservoir areas have been formed. In response to the functional requirements of flood control, shipping, power generation, etc., the water level in the reservoir area has periodically fluctuated, forming a drawdown zone in the reservoir area within a certain elevation range, which has caused significant damage and degradation to the rock mechanical strength of the water-wading base of the high-steep and dangerous rocks in the reservoir area. The drawdown of the reservoir water level has become the main disaster-causing factor for the instability of high-steep and dangerous rocks in the reservoir area.

[0004] The rocks in the drawdown zone experience periodic changes of drying and saturation every year, that is, dry-wet cycles, which are the main cause of damage and degradation of rock mechanical strength. Compared with the disaster-causing process of the river system's downcutting effect, the dry-wet cycle accelerates the formation and instability of high and steep dangerous rocks in the reservoir area. Typical cases include the dangerous rocks of Jianchuandong, Banbiyan, Longmenzhai, Guanmuling, and Huangyanwo in the Three Gorges Reservoir area.

[0005] Studying the mechanical strength damage law of rock in the drawdown zone under the influence of dry-wet cycles has become an important research content to reveal the instability mechanism of high-steep and dangerous rocks in reservoir areas. So far, a large number of researchers have carried out rock mechanical strength tests under dry-wet cycle conditions and revealed the characteristics of related laws. The main conclusions are: (1) The degree of degradation of rock mechanical strength gradually decreases and tends to be stable with the increase of dry-wet cycles, which conforms to the characteristics of negative exponential change law; (2) The stress-strain curve of rock conforms to the Weibull distribution model, and the creep deformation capacity gradually increases with the increase of dry-wet cycles; (3) The peak strength and residual strength of rock are lower under hydraulic coupling conditions, and the failure time occurs earlier; (4) The continuous increase of microscopic pores inside the rock under dry-wet cycle conditions is the essential reason for the damage and degradation of mechanical strength on a macro scale. The rock mechanics test technology used by the researchers can realize the rock mechanical strength test conditions of confining pressure and immersion coupling.

[0006] The rock mechanical strength test process under dry-wet cycle conditions carried out by the researchers has made a lot of test condition simplifications, which on the one hand makes the dry-wet cycle test results inconsistent with the actual situation, and on the other hand, ignores the influence of reservoir water seepage. For example, the water level drop in the reservoir area and the migration of reservoir water from high to low have a significant seepage effect on the rocks in the water-forged base of the high-steep and dangerous rocks in the reservoir area. This effect cannot be ignored under the geological and environmental conditions of the high-steep and dangerous rocks in the reservoir area, but researchers often ignore the influence of reservoir water seepage factors on the mechanical strength of rocks.

[0007] For rocks in the drawdown zone at a certain elevation, the seepage effect of the drawdown of the reservoir water level is short-lived and the resulting seepage effect is vertical, while the seepage effect of the reservoir water moving from high to low is long-term and the resulting seepage effect is horizontal. The saturation and drying processes caused by short-term vertical seepage effects can be achieved by dry-wet cycle pretreatment, while the damage and deterioration caused by long-term horizontal seepage effects are more significant. Researchers are often unable to achieve rock mechanical strength test conditions of confining pressure, immersion and seepage coupling.

[0008] CN 111024577 B provides a test device for the influence of immersion-undermining coupling on the mechanical properties of soil. The patent uses a pressure system, a water supply system, a sand-water separation measurement system and an automated confining pressure system to study the mechanical strength of soil under the conditions of confining pressure, immersion and seepage coupling test. However, the method for implementing the immersion and seepage coupling test conditions is a one-dimensional vertical seepage mode, and the rocks at the high-steep and dangerous rock wading base in the reservoir area are mainly affected by two-dimensional horizontal seepage, resulting in a narrow scope of application of the test device and method. In addition, the pressure system involved in the patent is only suitable for soils with low mechanical strength. Compared with the conventional triaxial rock mechanical strength test device, the application range and test accuracy of the pressure system involved in the patent cannot meet the mechanical strength test of hard carbonate rocks in the reservoir area.

[0009] In summary, in order to realize the rock mechanics strength test under dry-wet cycle conditions of confining pressure, immersion and seepage coupling, it is necessary to invent a rock mechanics test technology to realize the test conditions, and the present invention is an improvement and innovation based on the conventional triaxial rock mechanics strength test device. The rock mechanics strength under dry-wet cycle conditions can be obtained by using a conventional triaxial rock mechanics strength test device under relevant specifications and standards, but it is still necessary to further obtain the damage law of rock mechanics strength affected by reservoir water seepage. This has important theoretical value and practical significance for revealing the study of the instability mechanism of high and steep dangerous rocks in the reservoir area affected by the water level drawdown in the reservoir area, which is the driving force and original intention of the design of the present invention. Summary of the invention

[0010] In order to overcome the above-mentioned prior art and defects, the inventors conducted in-depth investigation, discussion and research, and completed the present invention after paying a lot of creative work.

[0011] Specifically, the technical problem to be solved by the present invention is that after the rock test sample has undergone the dry-wet cycle pretreatment process under the existing technical conditions, the rock test sample meets one of the geological conditions and environmental conditions of the rock in the high-steep and dangerous rock wading base in the actual reservoir area. On this basis, a triaxial instrument rock mechanics strength test auxiliary device for rock test samples under different water solution conditions and different seepage environmental conditions is provided. The auxiliary device can realize different water solution conditions such as changes in pH, changes in ion concentration, changes in water source, changes in water temperature, and at the same time can realize different seepage environmental conditions such as changes in water flow velocity, changes in water flow impact angle, and changes in water flow pressure.

[0012] In order to achieve the above object, the present invention provides the following technical solutions:

[0013] An auxiliary device for triaxial rock mechanics strength testing that realizes confining pressure, immersion and seepage coupling includes a water tank, a water flow control device, a system water pipe, a two-dimensional water flow control device, a diversion device, a diversion water pipe, a triaxial water tank, a temperature sensor, a water pressure gauge, a water flow meter and a data acquisition device. The water tank includes a heating and cooling rod, a temperature sensor and a water solution; The water flow control device includes a large water flow meter; connected to the water tank through a water tank outlet pipe and a water tank return pipe; the two-dimensional water flow control device includes a two-dimensional water flow control device water injection slot, a type I diversion guide plate, a type II diversion guide plate, a square water tank, a square water tank cover and a two-dimensional water flow control device water outlet slot; one end of the two-dimensional water flow control device water injection slot is connected to the water outlet of the water flow control device through a system water pipe; one type I diversion guide plate and multiple diversion guide plates are inserted into the square water tank in sequence according to the water flow direction; The square water tank cover is installed on the square water tank; the two-dimensional water flow control device water injection slot and the two-dimensional water flow control device water outlet slot are connected to the square water tank in an outer shell connection manner; The diversion device includes a plurality of pipes, a small water flow meter and a water outlet slot of the diversion device; one end of the water pipe is connected to the water outlet of the water outlet slot 14 of the two-dimensional water flow control device, and the other end is connected to the water injection port of the small water flow meter; the water outlet of the small water flow meter is connected to another diversion water pipe, and the other end of the other diversion water pipe is connected to the water outlet slot of the diversion device; The triaxial instrument water tank includes a temperature sensor, a water blocking baffle and a water pressure gauge; water blocking baffles are installed at different positions of the triaxial instrument water tank according to seepage environmental conditions at different water flow impact angles; another slit is connected to the water outlet slot of the diversion device; a water pressure gauge is installed at the water outlet of the triaxial instrument water tank, and is connected to the return port of the water flow control device through a system water pipe; a temperature sensor is installed inside the triaxial instrument water tank. The water tank provides storage for different water solutions and can also achieve the water temperature change value required for the rock mechanics strength test. The water flow control device provides the power for water movement. The two-dimensional water flow control device realizes the transformation from one-dimensional water flow to two-dimensional water flow. The diversion device is connected to the water outlet slot of the two-dimensional water flow control device, and two-dimensional water flow is led out by multiple diversion water pipes respectively, and a water flow meter is connected to the diversion water pipe to monitor the water flow speed. The triaxial instrument water tank is connected to the diversion device water outlet slot. The water body flows back to the water tank from the triaxial instrument water tank outlet through the water pressure gauge, system water pipe and water flow control device, realizing the internal and external water flow circulation of the rock mechanics strength test. The monitoring data obtained by the water tank temperature sensor, the triaxial instrument water tank temperature sensor, the water pressure gauge, the water flow meter and the triaxial instrument will be recorded and stored in real time by the data acquisition device.

[0014] In the present invention, as an improvement and innovation, the two-dimensional water flow control device is composed of a square water tank, a square water tank cover, a diversion guide plate, a water injection slot and a water outlet slot, all of which are made of acrylic plate materials and assembled together by screws and rubber washers. The square water tank cover is embedded in the square water tank. The diversion guide plate is divided into type I and type II. The type I diversion guide plate is dense and impermeable in the middle, and has small water-permeable holes at both ends. The size of the water-permeable holes is 5mm×5mm, and the spacing between the water-permeable holes is 5mm. The size of the panel covered with small water-permeable holes is one-third of the length of the diversion guide plate, and a total of 1 type I diversion guide plate. The type II diversion guide plate is completely covered with small water-permeable holes. The size of the water-permeable holes is 5mm×5mm, and the spacing between the water-permeable holes is 5mm. There are a total of 3 type II diversion guide plates, and two types of diversion guide plates are embedded in the square water tank. The size and specification of the water inlet of the water injection slot are consistent with the system water pipe, fixed by a clamp, and there is a total of 1 water inlet of the water injection slot, which is connected to the square sink through an outer sleeve connection. The size and specification of the water outlet of the water outlet slot are consistent with the diversion water pipe, fixed by a clamp, and there are a total of 6 water outlets of the water outlet slot, which are connected to the square sink through an outer sleeve connection.

[0015] In the present invention, as an improvement and innovation, the diversion device is composed of a diversion water pipe, a water flow meter and a water outlet slot. The water outlet slot of the diversion device is made of acrylic plate material and is connected to each other by clamps. The diversion water pipe adopts a steel wire threaded water pipe, and there are 12 diversion water pipes in total. The size and specifications are consistent with the water flow meter. One end is connected to the water outlet of the water outlet slot of the two-dimensional water flow control device, and the other end is connected to the water flow meter. The water flow meter is installed between the two diversion water pipes, and there are 6 water flow meters in total. The size and specifications of the water outlet slot water injection port are consistent with the diversion water pipe, and are fixed by a clamp. There are 6 water outlet slot water injection ports in total.

[0016] In the present invention, as an improvement and innovation, the triaxial instrument water tank is improved and innovated on the basis of the conventional triaxial instrument water tank, and is composed of a water tank, a water blocking baffle, a water pressure gauge and a temperature sensor. The water blocking baffle is made of acrylic plate material, and is assembled and combined with each other by screws and rubber washers. Three slits are opened on one side of the triaxial instrument water tank, which can be connected with the water outlet slot of the diversion device, and a circular hole is opened on the other side, and its size specification is consistent with the water pressure gauge. The water blocking baffle is connected with the slit of the triaxial instrument water tank in conjunction with the water outlet slot of the diversion device according to different water flow impact angle test conditions. There are 2 water blocking baffles in total, and the water flow impact angles that can be achieved are 0°, 30° and 45° respectively.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The device of the present application can realize the triaxial rock mechanics strength test conditions of confining pressure, immersion and seepage coupling.

[0019] (2) The device of the present application is designed with a two-dimensional water flow control device. This device can realize the transformation of one-dimensional water flow to two-dimensional water flow. Compared with the use of six water flow control devices, system water pipes and supporting equipment at the same time, it can save more costs for the production of materials and instruments for the triaxial rock mechanics strength test auxiliary device that realizes confining pressure, immersion and seepage coupling. Practice has proved that the two-dimensional water flow control device has a good diversion effect and anti-seepage effect.

[0020] (3) The device of this application is designed with a diversion device. The water flow velocity can be monitored in real time through the diversion water pipe and the water flow meter, avoiding the triaxial rock mechanics strength test of confining pressure, immersion and seepage coupling under non-uniform speed conditions, and realizing the actual geological conditions and environmental conditions of the rock in the high-steep and dangerous rock wading base in the reservoir area. Practice has proved that the diversion device has a good diversion effect and anti-seepage effect.

[0021] (4) The device of this application is designed with a triaxial instrument water tank, which is an improvement and innovation on the basis of the conventional triaxial instrument water tank, and can be smoothly assembled and combined with the diversion device, the water blocking baffle, and the water pressure gauge. After the water tank is connected with the water outlet slot of the diversion device in conjunction with the water blocking baffle, the triaxial instrument rock mechanics strength test of confining pressure, immersion and seepage coupling under different water flow impact angles can be realized. Practice has proved that the triaxial instrument water tank has a good diversion effect and anti-seepage effect.

[0022] (5) The device of the present application is designed with an internal and external water circulation system, which is composed of a water tank, a water flow control device, a system water pipe, a two-dimensional water flow control device, a diversion device and a triaxial instrument water tank, which work together to realize the recycling of water solutions. The temperature sensor, water pressure gauge, water flow meter and data acquisition equipment are used to monitor the real-time data such as water temperature, water flow velocity, and water flow pressure of the internal and external water flow circulation system in real time. The triaxial instrument rock mechanics strength test device monitors the stress-strain curve data of the rock test sample in real time. Among them, the water tank can realize different water solution conditions such as changes in pH, changes in ion concentration, changes in water source, and changes in water temperature. The system can also realize different seepage environmental conditions such as changes in water flow velocity, changes in water flow impact angle, and changes in water flow pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the device of the present invention, the following is a brief introduction to the drawings required for describing the device of the present invention. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work.

[0024] Figure 1It is a schematic diagram of a triaxial rock mechanics strength test auxiliary device that realizes the coupling of confining pressure, immersion and seepage.

[0025] Figure 2 It is a schematic diagram of the water filling slot of the two-dimensional water flow control device.

[0026] Figure 3 Schematic diagram of type I and type II flow diversion guide plates.

[0027] Figure 4 It is a schematic diagram of a square sink.

[0028] Figure 5 It is a schematic diagram of a square sink cover.

[0029] Figure 6 It is a schematic diagram of the water outlet slot of the two-dimensional water flow control device.

[0030] Figure 7 It is a schematic diagram of the water outlet slot of the diversion device.

[0031] Figure 8 It is a schematic diagram of a water blocking baffle.

[0032] Fig. 9 It is a schematic diagram of the triaxial instrument water tank.

[0033] Fig.10 This is a schematic diagram of the triaxial rock mechanics strength test under different water flow impact angles.

[0034] Legend:

[0035] 1. Water tank; 2. Heating and cooling rods; 3. Temperature sensor; 4. Water solution; 5. Water tank outlet pipe; 6. Water flow control equipment; 7. Large water flow meter; 8. System water pipe; 9. Two-dimensional water flow control device water injection slot; 10. Type I diversion guide plate; 11. Type II diversion guide plate; 12. Square water tank; 13. Square water tank cover; 14. Two-dimensional water flow control device water outlet slot; 15. Diversion water pipe; 16. Small water flow meter; 17 , water outlet slot of diversion device; 18, water blocking baffle; 19, rock test sample; 20, triaxial instrument loading plate; 21, triaxial instrument water tank; 22, water pressure gauge; 23, water tank return pipe; 24, water tank temperature sensor data cable; 25, large water flow meter data cable; 26, small water flow meter data cable; 27, triaxial instrument data cable; 28, triaxial instrument water tank temperature sensor data cable; 29, water pressure gauge data cable; 30, data acquisition equipment. DETAILED DESCRIPTION

[0036] In order to enable technicians in the field of rock mechanics testing technology to better understand the technical solutions in the present invention, the technical solutions in the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following embodiments are only used to more clearly illustrate the technical solutions in the present invention and are only used as examples, and cannot be used to limit the scope of protection of the present invention.

[0037] like Figure 1 As shown, a triaxial rock mechanics strength test auxiliary device for realizing confining pressure, immersion and seepage coupling includes a water tank, a water flow control device, a system water pipe, a two-dimensional water flow control device, a diversion device, a diversion water pipe, a triaxial water tank, a temperature sensor, a water pressure gauge, a water flow meter and a data acquisition device.

[0038] The water tank 1 includes a heating and cooling rod 2, a temperature sensor 3 and a water solution 4.

[0039] The water flow control device 6 includes a large water flow meter 7 and is connected to the water tank 1 through a water tank outlet pipe 5 and a water tank return pipe 23 .

[0040] The two-dimensional water flow control device includes a two-dimensional water flow control device water injection slot 9, a type I diversion guide plate 10, a type II diversion guide plate 11, a square water tank 12, a square water tank cover 13 and a two-dimensional water flow control device water outlet slot 14. One end of the two-dimensional water flow control device water injection slot 9 is connected to the water outlet of the water flow control device 6 through a system water pipe 8. One type I diversion guide plate 10 and three type II diversion guide plates 11 are inserted into the square water tank 12 in sequence according to the direction of water flow, and the square water tank cover 13 is further installed on the upper part of the square water tank 12, and assembled together by screws and rubber washers. The two-dimensional water flow control device water injection slot 9 and the two-dimensional water flow control device water outlet slot 14 are connected to the square water tank 12 in an outer sleeve joint manner, and assembled together by screws and rubber washers. A clamp is used to fix and seal the water pipe interface.

[0041] The diversion device includes a diversion water pipe 15, a small water flow meter 16 and a diversion device water outlet slot 17. One end of the diversion water pipe 15 is connected to the water outlet of the two-dimensional water flow control device water outlet slot 14, and the other end is connected to the water injection port of the small water flow meter 16. The water outlet of the small water flow meter 16 is connected to another diversion water pipe 15, and the other end of the diversion water pipe 15 is connected to the diversion device water outlet slot 17. The water pipe interface is fixed and sealed with a clamp.

[0042] The triaxial instrument water tank 21 includes a temperature sensor 3, a water blocking baffle 18 and a water pressure gauge 22. According to the test purpose of the seepage environment conditions at different water flow impact angles, two water blocking baffles 18 are installed at different slit positions of the triaxial instrument water tank 21, and another slit is connected to the water outlet slot 17 of the diversion device, and assembled together by screws and rubber washers. A water pressure gauge 22 is installed at the water outlet of the triaxial instrument water tank 21, and is connected to the return port of the water flow control device 6 through the system water pipe 8. A temperature sensor 3 is installed inside the triaxial instrument water tank 21.

[0043] The data acquisition system is composed of various sensor devices and a data acquisition device 30 .

[0044] The rock mechanics strength test method of this embodiment is as follows:

[0045] Wet-dry cycle, hydraulic coupling and water flow migration were all considered during the rock mechanical strength test. In order to test the mechanical strength damage law of rocks in the high-steep and dangerous rock wading base area under geological conditions and environmental conditions in the reservoir area, this test was divided into four groups of tests. The first group is dry and natural conditions, the second group is dry-wet cycle conditions, the third group is hydraulic coupling conditions, and the fourth group is water flow migration conditions. Test variables: the number of dry-wet cycles is 1 / 5 / 10 / 15 / 20 / 25 / 30 / 35 / 40 / 45 / 50 respectively; the preset values ​​of hydraulic coupling confining pressure are 0.10, 0.20 and 0.30MPa respectively (calculated according to the head difference of 10, 20 and 30m drawdown zone); taking the Three Gorges Reservoir area as an example, the average water velocity of the Yangtze River after the Three Gorges Dam is filled with water is 0.5m / s, and the difference is 0.2m / s above and below this basis, and the water flow migration velocity is preset. The values ​​are set to be 0.1 / 0.3 / 0.5 / 0.7 / 0.9m / s respectively; taking the Three Gorges Reservoir area as an example, the average water flow angle of the Yangtze River and its tributaries in the canyon section is 30°, on this basis, the difference of 15 to 30° is taken up and down, and the water flow impact angles are 0°, 30° and 45° respectively; taking the Three Gorges Reservoir area as an example, the water of the Yangtze River is used as the water required for the test to meet the environmental conditions of the rocks in the high, steep and dangerous rock wading base area of ​​the reservoir area; the water temperature is constant at 25°C.

[0046] Step 1: Place the rock test sample in an oven and dry it at 105℃ for 24h, then transfer it to a moisturizing cylinder, cool it to room temperature 25℃, and then dry it again for 2h. The drying is completed when the difference in mass between the two does not exceed 0.1% of the former. The saturation methods of the dry-wet cycle pretreatment process of rocks in the high-steep and dangerous rock wading base in the reservoir area include layered immersion method, complete immersion method and vacuum saturation method. At room temperature of 25℃, the rock test sample that has undergone drying is soaked in the Yangtze River water for 6h in a vacuum of 0.10, 0.20 and 0.30MPa (calculated according to the head difference of 10, 20 and 30m drawdown zone) to saturation, and wipe off the excess water droplets on the sample surface with a paper towel. A complete dry-wet cycle is one drying and one saturation. The technicians prepare the rock test samples after n dry-wet cycle pretreatments according to the test variables.

[0047] Step 2: Referring to relevant specifications and standards, place the rock test sample at the test position inside the triaxial instrument water tank, and install all components according to the technical solution of the present invention. In this step, the triaxial instrument water tank, water blocking baffle and water outlet slot of the diversion device are installed according to the test variables to meet the seepage environment conditions of different water flow impact angles.

[0048] Step 3: Based on the test variables such as water source and water temperature, inject the required water solution into the water tank.

[0049] Step 4: The water flow control equipment provides the motive force for water movement. By adjusting the water pump power and water pressure gauge of the water flow control equipment, the confining pressure in the water tank of the triaxial instrument is increased at a rate of 0.01MPa / s to the confining pressure required for the rock test sample. The confining pressure formed is the dynamic water confining pressure. After the confining pressure value stabilizes, the water flow in the water tank of the triaxial instrument is increased at a rate of 0.01m / s to the water flow velocity required for the rock test sample by adjusting the water pump power and water pressure of the water flow control equipment.

[0050] Step 5: After the confining pressure and water velocity values ​​are stable, the rock test sample is vertically loaded at a rate of 0.01 mm / min until it is destroyed by controlling the conventional triaxial rock mechanics strength test device, and the test is completed.

[0051] Step 6: The relevant test data are recorded and stored in real time by the data acquisition equipment. The stress and strain data of the rock test sample are obtained in real time by the conventional triaxial rock mechanical strength test device. The water flow pressure is monitored in real time by the triaxial water tank water pressure gauge. The water flow velocity is monitored in real time by the small water flow meter of the diversion device. During the test, the acoustic emission monitoring device and high-speed camera are used to record the whole process of rock test sample failure characteristics in real time.

[0052] The above is only an example of the rock mechanics strength testing method of the present invention, and the protection scope of the present invention is not limited to the above embodiment. For those skilled in the art, improvements and changes obtained without departing from the technical concept of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A triaxial rock mechanics strength test auxiliary device that realizes confining pressure, immersion and seepage coupling, including a water tank, a water flow control device, a system water pipe, a two-dimensional water flow control device, a diversion device, a diversion water pipe, a triaxial water tank, a temperature sensor, a water pressure gauge, a water flow meter and a data acquisition device; The water tank includes a heating and cooling rod, a temperature sensor and a water solution; The water flow control device includes a large water flow meter, which is connected to the water tank through a water tank outlet pipe and a water tank return pipe; The two-dimensional water flow control device comprises a two-dimensional water flow control device water injection slot, a type I diversion guide plate, a type II diversion guide plate, a square water tank, a square water tank cover and a two-dimensional water flow control device water outlet slot; one end of the two-dimensional water flow control device water injection slot is connected to the water outlet of the water flow control device through a system water pipe; one type I diversion guide plate and a plurality of diversion guide plates are sequentially inserted into the square water tank according to the water flow direction; The square water tank cover is installed on the square water tank; the two-dimensional water flow control device water injection slot and the two-dimensional water flow control device water outlet slot are connected to the square water tank in an outer shell connection manner; The diversion device includes a plurality of pipes, a small water flow meter and a water outlet slot of the diversion device; one end of the water pipe is connected to the water outlet of the water outlet slot 14 of the two-dimensional water flow control device, and the other end is connected to the water injection port of the small water flow meter; the water outlet of the small water flow meter is connected to another diversion water pipe, and the other end of the other diversion water pipe is connected to the water outlet slot of the diversion device; The triaxial instrument water tank includes a temperature sensor, a water blocking baffle and a water pressure gauge; water blocking baffles are installed at different positions of the triaxial instrument water tank according to seepage environmental conditions at different water flow impact angles; another slit is connected to the water outlet slot of the diversion device; a water pressure gauge is installed at the water outlet of the triaxial instrument water tank, and is connected to the return port of the water flow control device through a system water pipe; a temperature sensor is installed inside the triaxial instrument water tank.

2. The triaxial rock mechanics strength test auxiliary device for realizing confining pressure, immersion and seepage coupling according to claim 1, characterized in that: The two-dimensional water flow control device is composed of a square water tank, a square water tank cover, a diversion guide plate, a water filling slot and a water outlet slot, all of which are made of acrylic plate materials and assembled together by screws and rubber washers; the square water tank cover is embedded in the square water tank; the diversion guide plate is divided into type I and type II. The type I diversion guide plate is dense and impermeable in the middle and has small water holes at both ends. The size of the water holes is 5mm×5mm, and the distance between the water holes is 5mm, which is full of small water holes. The size of the water permeable hole panel is one-third of the length of the diversion guide plate, with a total of 1 Type I diversion guide plate; the Type II diversion guide plate is fully covered with small water permeable holes, the size of the water permeable holes is 5mm×5mm, and the distance between the water permeable holes is 5mm. There are a total of 3 Type II diversion guide plates, and the two types of diversion guide plates are embedded in the square water tank; the size of the water injection slot water injection port is consistent with the system water pipe, fixed by a clamp, and there is a total of 1 water injection slot water injection port, which is connected to the square water tank through an outer sleeve connection; The size and specification of the water outlet of the water outlet slot are consistent with those of the diversion water pipe, which is fixed by a clamp. There are a total of 6 water outlets of the water outlet slot, which are connected to the square sink through an outer sleeve connection.

3. The triaxial rock mechanics strength test auxiliary device for realizing confining pressure, immersion and seepage coupling according to claim 1, characterized in that: The diversion device is composed of a diversion water pipe, a water flow meter and a water outlet slot; the water outlet slot of the diversion device is made of acrylic plate material and is connected to each other by clamps; the diversion water pipe is a steel threaded water pipe, and there are 12 diversion water pipes in total, with dimensions consistent with the water flow meter, one end of which is connected to the water outlet of the water outlet slot of the two-dimensional water flow control device, and the other end is connected to the water flow meter; the water flow meter is installed between two diversion water pipes, and there are 6 water flow meters in total; the water outlet slot water inlet has dimensions consistent with the diversion water pipe and is fixed by a clamp, and there are 6 water outlet slot water inlet.

4. The triaxial rock mechanics strength test auxiliary device for realizing confining pressure, immersion and seepage coupling according to claim 1, characterized in that: The triaxial instrument water tank is improved and innovated on the basis of the conventional triaxial instrument water tank, and is composed of a water tank, a water blocking baffle, a water pressure gauge and a temperature sensor; the water blocking baffle is made of acrylic plate material, and is assembled together with screws and rubber washers; three slits are opened on one side of the triaxial instrument water tank, which are connected to the water outlet slot of the diversion device, and a circular hole is opened on the other side, and its size specification is consistent with the water pressure gauge; the water blocking baffle is connected to the slit of the triaxial instrument water tank in accordance with different water flow impact angle test conditions in conjunction with the water outlet slot of the diversion device, and there are 2 water blocking baffles in total, and the achievable water flow impact angles are 0°, 30° and 45° respectively.

5. The triaxial rock mechanics strength test auxiliary device for realizing confining pressure, immersion and seepage coupling according to claim 1, characterized in that: The internal and external water flow circulation system is composed of a water tank, water flow control equipment, system water pipes, a two-dimensional water flow control device, a diversion device and a triaxial instrument water tank, which work together to realize the recycling of water solutions; the temperature sensor, water pressure gauge, water flow meter and data acquisition equipment are used to monitor the water temperature, water flow velocity and water flow pressure of the internal and external water flow circulation system in real time, and the triaxial instrument rock mechanics strength testing device is used to monitor in real time to obtain the stress-strain curve data of the rock test samples; the water tank realizes different water solution conditions such as changes in pH, changes in ion concentration, changes in water source and changes in water temperature; the system can also realize different seepage environment conditions such as water flow velocity, water flow impact angle and water flow pressure.

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