On-site seepage failure test system for altered rock mass

Abstract

The utility model provides an alteration rock mass on-site seepage failure test system. The alteration rock mass on-site seepage failure test system comprises a high-pressure water pressing system for supplying water and an observation system for observation, the high-pressure water pressing system comprises a water tank, the interior of the water tank is connected with a water pump through a water inlet pipe, a water outlet of the water pump is connected with a floral tube through a water pipe, the floral tube is arranged in a test section of the test hole, the top of the test section of the test hole is plugged through a water stop plug, and the water pipe penetrates through the water stop plug; the observation system comprises a water level measuring instrument used for measuring the water level in the observation hole, and a water collecting system is arranged at the opening position of the observation hole and connected with a water collecting tank. According to the system, the seepage failure characteristics of altered rock mass are measured on site, and rock mass permeability coefficients and seepage failure parameters which are close to reality are provided.

Description

Technical Field

[0001] The utility model relates to the technical field of water conservancy and hydropower engineering, in particular to an altered rock mass on-site penetration and destruction test system. Background Art

[0002] As a special engineering geological problem, rock mass alteration has an increasingly prominent impact on the construction of large-scale water conservancy and hydropower projects. The seepage and damage characteristics of altered rock mass at the dam foundation directly affect the stability of the dam foundation and the selection of anti-seepage solutions. Therefore, studying the seepage and damage characteristics of altered rock is of great engineering significance for taking reasonable and reliable treatment measures, accelerating construction progress, ensuring construction safety, and ensuring the stability of the dam foundation.

[0003] Since altered rocks generally have poor physical and mechanical properties, the rock mass is broken and severely argillaceous, it is difficult to take samples for indoor permeability tests on altered rocks. The reshaping of disturbed samples is quite different from the on-site state, and the original samples are difficult to prepare, transport and preserve. The indoor test data cannot reflect the actual situation on site. At the same time, it is difficult to take samples in deep areas of altered rocks. The borehole water pressure test is the most commonly used test method for on-site determination of rock permeability in water conservancy and hydropower projects. However, due to the poor physical and mechanical properties of altered rocks, the conventional single-hole high-pressure water pressure test used to determine permeability damage is difficult to implement. Utility Model Content

[0004] In order to solve the current technical problems, the main purpose of the utility model is to provide an on-site permeability failure test system for altered rock mass. This system and method can measure the permeability failure characteristics of altered rock mass on-site and provide rock mass permeability coefficient and permeability failure parameters that are closer to the actual ones.

[0005] In order to realize the above technical features, the purpose of the utility model is achieved as follows: an altered rock mass field penetration damage test system, including a high-pressure water pressure system for water supply and an observation system for observation;

[0006] The high-pressure water pressure system includes a water tank, the interior of the water tank is connected to a water pump through a water inlet pipe, the water outlet of the water pump is connected to a flower pipe through a water pipe, the flower pipe is arranged inside the test section of the test hole, the top of the test section of the test hole is blocked by a water stop plug, and the water pipe passes through the water stop plug;

[0007] The observation system comprises a water level measuring instrument for measuring the water level inside the observation hole. A water collection system is arranged at the orifice position of the observation hole, and the water collection system is connected to the water collection tank.

[0008] The water tank is arranged on the top of the rock mass.

[0009] A first flow meter and a pressure gauge are installed on the water pipe.

[0010] The non-test sections of the test hole and the observation hole are respectively covered with casings.

[0011] The water level measuring instrument is arranged on the top of the rock mass, and the measuring head extends into the inside of the observation hole.

[0012] A second flow meter is installed on the connecting pipe between the water collecting system and the water collecting tank.

[0013] The water collecting tank is arranged on the top of the rock mass.

[0014] The utility model has the following beneficial effects:

[0015] 1. The utility model adopts an on-site cross-hole high-pressure water pressure test to test the permeability and damage characteristics of the altered rock mass, thus avoiding the difficulty of indoor test sampling and the large difference between the test data and the actual problem.

[0016] 2. The utility model adopts an on-site cross-hole high-pressure water pressure test to test the permeability and damage characteristics of the altered rock mass. Multiple tests can be carried out within different depth ranges, solving the difficulties in stratified sampling and deep sampling.

[0017] 3. The utility model adopts a cross-hole high-pressure water pressure test method, which can measure the permeability coefficient of the altered rock mass on site relatively close to the actual situation, and analyze the permeability type through the observation hole, which has important guiding significance for engineering design and safe production.

[0018] 4. The utility model adopts a close-range cross-hole high-pressure water penetration damage test. By reducing the seepage diameter, the rock penetration damage parameters can be measured through cross-hole penetration damage under a relatively small pressure, which solves the problem of severe rock damage at the water stop plug and water stop failure when the pressure of the altered rock mass is too large in the conventional water pressure test.

[0019] 5. The utility model combines wave velocity, in-hole television and other geophysical observation methods for comprehensive analysis, which can more closely judge the type of infiltration and the form of damage, thereby providing stronger support for the selection of design treatment solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Figure 1 It is a layout diagram of the test system of the utility model.

[0022] Figure 2 The utility model is a flow chart of a test method for testing the on-site penetration and destruction characteristics of altered rock mass.

[0023] In the figure: water tank 1, water pump 2, first flow meter 3, pressure gauge 4, water level measuring instrument 5, water collection system 6, water collection tank 7, casing 8, water stop plug 9, flower pipe 10, test hole 11, observation hole 12, second flow meter 13, water pipe 14. DETAILED DESCRIPTION

[0024] The embodiments of the present utility model are further described below in conjunction with the accompanying drawings.

[0025] Embodiment 1:

[0026] See also Figure 1 A field permeability damage test system for altered rock mass includes a high-pressure water pressure system for water supply and an observation system for observation; the high-pressure water pressure system includes a water tank 1, the interior of the water tank 1 is connected to a water pump 2 through a water inlet pipe, the water outlet of the water pump 2 is connected to a flower pipe 10 through a water pipe 14, the flower pipe 10 is arranged inside a test section of a test hole 11, the top of the test section of the test hole 11 is blocked by a water stop plug 9, and the water pipe 14 passes through the water stop plug 9; the observation system includes a water level measuring instrument 5 for measuring the water level inside the observation hole 12, a water collection system 6 is arranged at the orifice position of the observation hole 12, and the water collection system 6 is connected to a water collection tank 7. The permeability damage characteristics of the altered rock mass are measured on site through the above test system and method, and rock mass permeability coefficient and permeability damage parameters that are closer to the actual ones are provided.

[0027] Furthermore, the water tank 1 is arranged on the top of the rock mass. The water tank 1 can be used to supply water to the test process.

[0028] Furthermore, a first flow meter 3 and a pressure gauge 4 are installed on the water pipe 14. The first flow meter 3 can be used to monitor the water supply during the test, and the pressure gauge 4 is used to control the pressure during the water pressure process.

[0029] Furthermore, the non-test sections of the test hole 11 and the observation hole 12 are respectively covered with casings 8. The casings 8 are used to protect the non-test area.

[0030] Furthermore, the water level measuring instrument 5 is arranged on the top of the rock mass, and the measuring head extends into the inside of the observation hole 12. The water level measuring instrument 5 is convenient for monitoring the water level of the observation hole.

[0031] Furthermore, a second flow meter 13 is installed on the connecting pipe between the water collection system 6 and the water collection tank 7. The second flow meter 13 facilitates flow monitoring of the water collection.

[0032] Further, the water collecting box 7 is arranged on the top of the rock mass, so as to facilitate the collection of seepage water.

[0033] Embodiment 2:

[0034] See also Figure 2 , a method for testing on-site penetration damage of altered rock mass, the test method is implemented by the test system, and comprises the following steps:

[0035] S1, drilling the test hole 11 and the observation hole 12 to the test section respectively, and setting casing 8 in the non-test section for isolation; observing the water level in the test section before the test and measuring the acoustic wave and television in the hole;

[0036] S2, install a high-pressure water pressure system in the test hole 11: place a water stop plug 9 on the upper part of the test section of the test hole 11, fix the test section with a flower tube 10 and connect it to a water pipe 14, install a water pump 2, a first flow meter 3, and a pressure gauge 4 on the water inlet pipe; perform test water pressure to ensure that the water stop plug 9 has a reliable water stop effect;

[0037] S3, installing an observation system in the observation hole 12: placing a water level measuring instrument 5 in the observation hole 12, and setting a water collection system 6 at the orifice of the observation hole 12 and connecting it to a second flow meter 13;

[0038] S4, high pressure water pressure test: the water pressure test is carried out at a pressure of not less than level 3 and not less than 5 stages; the test process adopts the fast method, slow method or cycle method as needed; at the same time, the observation hole 12 records the water level change and the backflow of the hole;

[0039] S5, in-hole observation: after taking out the high-pressure water pressure system, the test section of the test hole 11 is carried out in time, and the in-hole sound wave and in-hole television measurements are carried out after the test;

[0040] S6, penetration damage test: In the above high pressure water pressure test, if no penetration damage occurs between the holes, a test section is selected for a penetration damage test. The test process is the same as S2 to S5. The test pressure in S4 is gradually increased until penetration damage occurs.

[0041] S7, collation of test data, calculation of rock mass permeability coefficient based on high pressure water pressure test, analysis of failure forms based on observation results, and determination of rock mass permeability failure ratio based on permeability failure test.

[0042] Furthermore, the test rock mass is suitable for altered rock mass.

[0043] Furthermore, the drilling distance between the test hole 11 and the observation hole 12 in S1 is controlled within 2 m.

[0044] Furthermore, in the drilling process in S1, plant gum is added to the flushing fluid to protect the wall to prevent the hole wall from collapsing. The test section is flushed before the test. After the test is completed, the casing 8 is promptly lowered for isolation before the next test section is tested.

[0045] Furthermore, the maximum pressure in S4 is 1.2 to 1.5 times the maximum water head pressure of the project.

[0046] Furthermore, the process of 12 water pressure tests was observed through observation holes, and the penetration damage characteristics were comprehensively analyzed.

[0047] Furthermore, in S7, a water pressure test process curve is drawn and analyzed in combination with observation results.

[0048] Furthermore, in-hole wave velocity and in-hole television measurements were carried out before and after the test, combined with analysis of the penetration form and damage characteristics.

[0049] Embodiment 3:

[0050] This embodiment provides a test system and method for testing the permeability coefficient of altered rock mass on site. Figure 2 First, a test hole 11 and an observation hole 12 are arranged at intervals of 2 m in the test site, and a geological drilling rig is arranged at each of the two drilling positions to carry out drilling and coordination tests.

[0051] The test hole and observation hole are drilled into the test section, and the non-test section is isolated by casing 8. Figure 1 shown.

[0052] Carry out water level observation and in-hole acoustic wave and in-hole television measurement before the test section test.

[0053] like Figure 2 As shown, a high-pressure water pressure system is installed in the test hole: a water stop plug 9 is placed on the upper part of the test section, the test section is fixed with a flower pipe 10 and connected to the water pipe, and a water pump 2, a first flow meter 3, and a pressure gauge 4 are installed in the water inlet pipe.

[0054] Conduct test water pressure to ensure that the water-stopping effect of the water-stop plug 9 is reliable.

[0055] like Figure 2 As shown, an observation system is installed in the observation hole: a water level measuring instrument 5 is placed in the hole, and a water collection system 6 connected to a second flow meter 13 is provided at the hole mouth.

[0056] High-pressure water pressure test: The water pressure test is carried out at 3 levels of pressure and 5 stages. The test process adopts the slow method. At the same time, the observation hole records the water level changes and the water backflow at the hole.

[0057] In-hole observation: After taking out the water pressure test system, carry out in-hole acoustic wave and in-hole television measurements in time after the test section test.

[0058] After collating the test data, the on-site rock permeability coefficient can be calculated based on the above-mentioned high-pressure water pressure test, and the failure form can be analyzed based on the observation results.

[0059] Among them, a small amount of plant gum and other wall protection are added to the flushing fluid during the drilling process to prevent the hole wall from collapsing. The test section is washed before the test. After the test is completed, casing is promptly lowered for isolation before the next test section is tested.

[0060] Among them, in the high-pressure water pressure project, the maximum pressure is 1.5Mpa, which is 1.5 times the maximum water head pressure of the project of 1Mpa, and the pressure stage is carried out in seven stages: 0.3Mpa-0.6Mpa-1Mpa-1.5Mpa-1Mpa-0.6Mpa-0.3Mpa.

[0061] Among them, the slow method is adopted in the high-pressure water pressure project: the flow rate is recorded once every 1 minute in the first 5 minutes, and then every 5 minutes, and the flow rate is recorded for 5 consecutive times. After 30 minutes, the flow rate is recorded every 10 minutes. After the flow rate is stable after 5 consecutive readings, the pressure test at this stage can be ended.

[0062] In the process of data collation, a water pressure test process curve is drawn and analyzed in combination with observation results.

[0063] Embodiment 4:

[0064] This embodiment provides a test system and method for testing the permeability coefficient of altered rock mass on site. Figure 2 First, a test hole and an observation hole are arranged at an interval of 2m in the test site, and a geological drilling rig is arranged at each of the two drilling positions to carry out drilling and coordination tests.

[0065] The test hole and observation hole are drilled into the test section, and the non-test section is isolated by casing 8. Figure 2 shown.

[0066] Carry out water level observation and in-hole acoustic wave and in-hole television measurement before the test section test.

[0067] like Figure 2 As shown, a high-pressure water pressure system is installed in the test hole: a water stop plug 9 is placed on the upper part of the test section, the test section is fixed with a flower pipe 10 and connected to the water pipe, and a water pump 2, a flow meter 3, and a pressure gauge 4 are installed in the water inlet pipe.

[0068] Conduct test water pressure to ensure that the water-stopping effect of the embolism 9 is reliable.

[0069] like Figure 2 As shown, an observation system is installed in the observation hole: a water level measuring instrument 5 is placed in the hole, and a water collection system 6 connected to a flow meter 4 is provided at the hole mouth.

[0070] Permeability failure test: The water pressure test is carried out in a step-by-step pressure-increasing manner, with a pressure difference of 0.5MPa. When the pressure is increased to a certain level, the cracks will undergo tensile splitting, accompanied by a sudden increase in water permeability. This pressure is the permeability failure pressure value of the test section, which corresponds to the inflection point pressure value of the pressure-flow curve. At the same time, the observation hole records the water level changes and the backflow of the orifice.

[0071] In-hole observation: After taking out the water pressure test equipment, carry out in-hole acoustic wave and in-hole television measurements in time after the test section test.

[0072] The test data are collated, and the rock mass seepage failure ratio can be obtained based on the seepage failure test, and the failure form can be analyzed based on the observation results.

[0073] Among them, a small amount of plant gum and other wall protection are added to the flushing fluid during the drilling process to prevent the hole wall from collapsing. The test section is washed before the test. After the test is completed, casing is promptly lowered for isolation before the next test section is tested.

[0074] In the process of data collation, a water pressure test process curve is drawn and analyzed in combination with observation results.

Claims

1. A field permeability damage test system for altered rock mass, characterized in that: Includes a high-pressure water system for water supply and an observation system for observation; The high-pressure water pressure system comprises a water tank (1), the interior of the water tank (1) is connected to a water pump (2) via a water inlet pipe, the water outlet of the water pump (2) is connected to a flower tube (10) via a water pipe (14), the flower tube (10) is arranged inside a test section of a test hole (11), the top of the test section of the test hole (11) is blocked by a water stop plug (9), and the water pipe (14) passes through the water stop plug (9); The observation system comprises a water level measuring instrument (5) for measuring the water level inside the observation hole (12); a water collection system (6) is arranged at the orifice of the observation hole (12); and the water collection system (6) is connected to a water collection tank (7).

2. According to claim 1, an altered rock mass field penetration damage test system is characterized by: The water tank (1) is arranged on the top of the rock mass.

3. The altered rock mass field penetration and destruction test system according to claim 1, characterized in that: A first flow meter (3) and a pressure gauge (4) are installed on the water pipe (14).

4. The altered rock mass field penetration damage test system according to claim 1, characterized in that: The non-test sections of the test hole (11) and the observation hole (12) are each sleeved with a casing (8).

5. The altered rock mass field penetration and destruction test system according to claim 1, characterized in that: The water level measuring instrument (5) is arranged on the top of the rock mass, and the measuring head extends into the interior of the observation hole (12).

6. The altered rock mass field penetration and destruction test system according to claim 1, characterized in that: A second flow meter (13) is installed on the connecting pipe between the water collection system (6) and the water collection tank (7).

7. The altered rock mass field penetration damage test system according to claim 1, characterized in that: The water collecting tank (7) is arranged on the top of the rock mass.

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