System and method for rock mass quality evaluation of hydropower dam site

Abstract

The application discloses a system and method for evaluating rock mass quality in dam site area of a hydropower station, and belongs to the technical field of rock mass detection. The evaluation method evaluates the joint development condition of rock mass in the dam site area through the seepage water characteristics of the adit in the dam site area, and obtains the rock mass quality in the dam site area, and comprises the following steps: according to the joint characteristics of the adit wall in the dam site area, the adit wall is divided into a plurality of sub-regions by using a fence; the seepage water characteristics and water quality characteristics of each sub-region are obtained; the seepage water flow curve and the seepage water quality characteristic curve of each sub-region are obtained; the seepage water flow change rule and the seepage water quality characteristic change rule of each sub-region are obtained; and it is determined whether the joints covered by the sub-regions have internal connectivity. The system is used for realizing the method. According to the regional seepage water measurement based on the joint characteristics of the adit surface, the development state of the rock mass fault and fissure in the dam site area can be accurately obtained, which has promoting significance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock mass detection, in particular to a system and method for evaluating rock mass quality in dam site area of hydropower station. BACKGROUND

[0002] In the rock mass quality evaluation system of the dam site area of the hydropower station, the hydrogeological conditions of the dam site area are evaluated. The main groundwater in the dam site area is rock fissure phreatic water. The seepage of rock water is related to the development state of rock faults and fissures, and is related to the weathering and unloading degree of the rock mass. In engineering operation, the seepage of rock water in the dam site area is obtained from the geological structure and weathering and unloading of the dam site rock mass, which is of great significance to the evaluation of rock mass quality.

[0003] To obtain the water permeability of the dam site rock mass, the existing technology adopts technical means including water pressure test means and seepage water measurement and analysis means. The former generally uses a test device including a water supply system, a pressure stabilizing system and a data acquisition system to provide pressure water to the acting surface, and determines the permeability of the rock mass through indicators such as seepage pressure and flow rate during the process. The latter generally uses a water collection device to collect seepage water from the adit, and determines the development of the seepage channel in the adit area in combination with the rock water replenishment. However, the implementation of the latter depends on the presence of visible seepage water in the adit under the influence of natural precipitation. In addition, in these two technical means, the object for obtaining water permeability is generally the whole adit. The former water permeability obtaining scheme is provided in the technical solutions of patent application numbers CN202310483619.1, CN202210031736.X and CN202010556552.6. The latter water permeability obtaining scheme is to set a water collection channel and a water collection tank in the adit, and to obtain the characteristics of seepage water by monitoring the flow rate in the water collection channel and the capacity parameters of the water collection tank, which is used for judging the mechanical properties of the rock mass and the engineering stability.

[0004] To promote the rock mass quality evaluation work and ensure the construction quality of the dam area, it is necessary to further optimize the rock water seepage technology of the rock mass adit in the dam site area of the hydropower station. SUMMARY

[0005] In view of the above-mentioned problem of optimizing the rock water seepage technology of the rock mass adit in the dam site area of the hydropower station, the present application provides a system and method for evaluating rock mass quality in dam site area of hydropower station. According to the present application, regional seepage water measurement is carried out according to the joint characteristics of the adit surface, which is of great significance to accurately obtaining the development state of the rock faults and fissures in the dam site area.

[0006] The specific technical scheme is: a rock mass quality evaluation method for a dam site area of a hydropower station, the evaluation method obtains the rock mass quality of the dam site area by evaluating the joint development of the rock mass through the seepage water characteristics of the adit in the dam site area, in the method, the seepage water characteristics of the adit are obtained by setting a seepage water detection system in the adit, including the following steps:

[0007] S1, according to the joint characteristics of the rock mass of the dam site area, the adit wall is divided into a plurality of sub-regions by setting a fence on the adit wall, the fence serves as a waterproof wall between the sub-regions, the joints in the same sub-region have the apparent characteristics of mutual communication, and the joints in different sub-regions have the apparent characteristics of mutual disconnection;

[0008] S2, the seepage water characteristics of each sub-region are obtained by using a seepage water detection system, the seepage water characteristics include the seepage water flow at each time during the detection, and the seepage water flow curve of each sub-region is obtained according to the seepage water flow, the seepage water characteristics also include the water quality characteristics of the seepage water at the set time during the detection, the water quality characteristics are the content characteristics of the target ion component in the seepage water and / or the PH value characteristics of the seepage water, and the seepage water quality characteristic curve of each sub-region is fitted according to the water quality characteristics;

[0009] S3, according to the seepage water flow curve and the seepage water quality characteristic curve, the seepage water flow change law and the seepage water quality characteristic change law of each sub-region are obtained;

[0010] S4, for the sub-regions with the same seepage water flow change law and seepage water quality characteristic change law, these sub-regions are identified as the covered joints having internal connectivity, and the covered joints belong to the same continuous joint, for the sub-regions with different seepage water flow change law and seepage water quality characteristic change law, these sub-regions are identified as the covered joints being mutually disconnected joints.

[0011] The method provided above evaluates the joint development of the rock mass by the seepage water characteristics of the adit in the dam site area, thereby obtaining the rock mass quality related to the hydrogeology of the dam site area, and is an evaluation means based on seepage water measurement. It is different from the existing rock mass quality evaluation in that the existing water pressure test means and seepage water measurement analysis means only take the whole adit or the selected rock mass as the seepage evaluation object. Although the whole permeability of the object can be evaluated, the permeability of different joints on the complex address structure cannot be well distinguished, and the development state of different rock mass faults and fractures in the dam site area cannot be accurately distinguished. The specific evaluation method of the present scheme is as follows: first, from the apparent characteristics of the joints on the adit wall, the interconnected joints are divided into the same sub-region, and the disconnected joints are divided into different sub-regions. The different sub-regions are isolated by using a barrier. On this basis, the seepage water characteristics of each sub-region are used, and the seepage water flow and the seepage water quality are obtained to obtain the seepage water flow curve and the seepage water quality characteristic curve. Then, the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region are analyzed, and several sub-regions with the same seepage water flow variation law and seepage water quality characteristic variation law are identified as joints and fractures with internal connectivity, and sub-regions with different seepage water flow variation laws and seepage water quality characteristic variation laws are identified as different joints. These joints have the characteristic of being disconnected from each other.

[0012] Based on the above, for each region of the adit covered by the seepage water detection system, the present scheme determines whether the seepage water of these regions comes from the same seepage path through the seepage water characteristics. For example, for the seepage water characteristics detected by different seepage points, when the seepage points have the same seepage water source, although the seepage point position distribution will cause a significant flow change not at the same time, the seepage water flow variation law obtained from each sub-region can find that different sub-regions have similar flow variation laws at different times. Different fractures and faults developed independently in the rock mass do not have this characteristic. On the other hand, for the water quality characteristics, because the seepage water from different fractures and faults has different phreatic fractures and seepage paths, the difference in phreatic storage environment and the difference in the upper sediment of the path will cause the seepage water from different fractures and faults to have different water quality characteristics. Based on this concept, the present scheme carries out regional seepage water characteristic measurement according to the surface joint characteristics of the adit. It can not only obtain the fracture and fault development of the surrounding rock mass from the whole adit, but also distinguish the fractures and faults on the surrounding rock mass, providing more detailed seepage water characteristic data support for rock mass quality evaluation, thereby achieving the purpose of promoting the accurate acquisition of the development state of the rock mass faults and fractures in the dam site area.

[0013] In one embodiment, in the step S2, the method for obtaining the seepage water flow rate is to collect the seepage water at the seepage point and to drain the seepage water into a flow rate measuring device to complete the seepage water flow rate measurement.

[0014] For the seepage water with an estimated flow rate greater than or equal to a set flow rate value, a flow rate measuring device based on a flow meter is used to complete the seepage water flow rate measurement, and for the seepage water with an estimated flow rate less than or equal to the set flow rate value, a flow rate measuring device including a water storage device is used to complete the seepage water flow rate measurement, wherein the water storage device includes a water storage tank, a weighing device, and a conversion module, the water storage tank is used to collect the seepage water, the weighing device is used to measure the weight of the water storage tank at each time, and the conversion module is used to convert the measurement result of the weighing device into a flow rate value of the seepage water.

[0015] In the above scheme, two seepage water flow rate measurement methods are provided, wherein according to the current seepage water flow rate of the adit seepage point, for the seepage water with a larger estimated seepage water flow rate, a flow meter is used to directly measure the seepage water flow rate, and for the seepage water with a smaller estimated seepage water flow rate, a method based on measuring the weight is used to indirectly measure the seepage water flow rate. In this method, when the seepage water flow rate is large, using a flow meter to measure the flow rate not only has the characteristic of simple system configuration, but also has the characteristic of accurate measurement result; and although the method of indirectly measuring the flow rate by weight increases the system complexity, it can ensure the flow rate measurement accuracy under a smaller seepage water flow rate.

[0016] In one embodiment, a drain pipe with a solenoid valve is configured for the water storage tank, when it is necessary to obtain the water quality characteristics of the seepage water, the solenoid valve is opened to obtain a sample for water quality characteristic detection from the drain pipe, and when the seepage water in the water storage tank accumulates to a set weight, the solenoid valve is opened to discharge the original seepage water from the drain pipe.

[0017] In one embodiment, for the seepage points of the seepage water located on the side and top of the adit, according to the seepage water seepage form, for the seepage water flowing along the wall after seepage, a collection groove fixed to the adit wall and located below the seepage point is used to collect the seepage water, and a pipeline is used to drain the seepage water collected by the collection groove into a flow rate measuring device to complete the seepage water flow rate measurement; for the seepage water dripping or jetting after seepage, a receiving cover fixed to the adit wall or supported on the adit ground is used to collect the seepage water, and a pipeline is used to drain the seepage water collected by the receiving cover into a flow rate measuring device to complete the seepage water flow rate measurement.

[0018] In the above scheme, a method for collecting seepage water in different seepage forms is provided, specifically: the seepage water flowing along the wall after seepage is collected by a collection tank, and the seepage water dripping or jetting after seepage is collected by a receiving cover, so as to reduce the omission of seepage water collection as much as possible within the scope of convenient implementation, and obtain favorable seepage water characteristics. Further, after the seepage water at the seepage point is collected by the collection tank and the receiving cover, the seepage water in a single sub-region can be guided to a flow measuring device and a water quality characteristic detection device by using a pipe section, a drainage groove, a converging groove, etc. When it is determined through the seepage water characteristics in the early stage that the joints on the different sub-regions belong to the joints under the same crack or fault, a single flow measuring device and a single water quality characteristic detection device can be used to serve two or more sub-regions, so as to simplify the structure of the seepage water detection system in the subsequent process, optimize the use efficiency of the flow measuring device and the water quality characteristic detection device, and reduce the amount of data in the later stage.

[0019] In a specific embodiment, for joints with apparent characteristics of being interconnected and having multiple seepage points, a gap plugging material is used to plug the seepage points with relatively small flow, and the seepage water of the seepage points is collected from the remaining seepage points.

[0020] In the above scheme, for joints with more seepage points in a single sub-region, a gap plugging material is used to plug part of the seepage points with small flow, so as to improve the seepage water collection rate and simplify the structure of the seepage water detection system. The gap plugging material can be a commonly used water plugging material for building construction, but in specific applications, the seepage water characteristic evaluation online measurement duration is long, and during the online measurement time period, there are cases where the joints change significantly due to stress release of the rock mass, and there are cases where the remaining seepage points are plugged and new seepage points appear after the seepage points are intervened. It is more optimal to investigate the current seepage points during the online measurement time period, to adjust the seepage water collection scheme accordingly, and to obtain accurate seepage water characteristics in the long term.

[0021] In a specific embodiment, the target ions include one or more of sulfate ions, carbonate ions, bicarbonate ions, magnesium ions, and calcium ions. When the content characteristics are detected, the set time is the time when the seepage water detection system performs seepage water sampling according to the set sampling frequency of the target ion composition.

[0022] In the above scheme, the selected target ions are not only common ion components in seepage water, but also factors that need to be considered in the later construction of the dam. Therefore, such water quality characteristics not only distinguish rock fissures and faults, but also provide a reference for the later construction of the dam.

[0023] In one specific embodiment, when the seepage water cannot be obtained according to the natural rainfall in the dam site area, artificial simulated rainfall is provided for the rock-soil above the flat silt according to the natural rainfall records in the dam site area, wherein the rainfall amount of the artificial simulated rainfall matches the rainfall amount in the current season in the past years.

[0024] In the above scheme, when the seepage water seepage condition cannot meet the seepage water characteristic evaluation, the artificial intervention method is used to obtain the seepage water in the flat silt. Further, when the artificial intervention is performed, the rainfall amount in the current season is obtained from the natural rainfall records in the past years, and the artificial rainfall amount is equivalent to the rainfall amount in the current season in the past years. In this way, the safety of the rock mass quality evaluation process can be ensured, and the real influence of the local meteorological conditions on the hydrogeological conditions of the rock mass can be obtained by truly simulating the local hydrological conditions.

[0025] The present scheme also relates to a system for rock mass quality evaluation in a dam site area of a hydropower station, which is used to implement the rock mass quality evaluation method in the dam site area of the hydropower station as described above.

[0026] The system comprises a flow measurement device for obtaining the seepage water flow.

[0027] The system comprises a water quality characteristic detection device for obtaining the water quality characteristics of the seepage water.

[0028] The system comprises a data processing module for statistically or fittingly obtaining the seepage water flow curve and the seepage water quality characteristic curve of each sub-region, obtaining the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region, and judging the actual connection relationship of the joints covered by each sub-region according to the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region.

[0029] It is easy to understand that the system is used to implement the method proposed above. In use, the system automatically completes the seepage water flow acquisition, the water quality characteristic acquisition, the construction of the seepage water flow curve and the seepage water quality characteristic curve, the obtaining of the seepage water flow variation law and the seepage water quality characteristic variation law, and the identification of whether the joints covered by each sub-region are actually connected, so as to realize the automation of the rock mass quality evaluation in the dam site area based on the joint development of the rock mass.

[0030] In one specific embodiment, the flow measurement device comprises a flow measurement device based on a flow meter, and the flow measurement device further comprises a flow measurement device with a water storage tank, a weighing device, and a conversion module, wherein the water storage tank is used to collect the seepage water, the weighing device is used to measure the weight of the water storage tank at each time, and the conversion module is used to convert the measurement result of the weighing device into the flow value of the seepage water.

[0031] It is easy to understand that the present scheme provides a differentiated flow measuring device, so that the user can select the flow measuring device used according to the current seepage water flow, from the aspects of easy implementation and accurate acquisition of seepage water flow.

[0032] In one specific embodiment, the system further comprises a fence as a water barrier between sub-regions, the fence being a strip-shaped rubber profile with an L-shaped cross section, and the system further comprises a collection groove for collecting seepage water from the adit wall, the collection groove being a strip-shaped rubber profile with a U-shaped cross section, the fence and the collection groove being provided with compression nails for fixing them on the adit wall, and the nail caps of the compression nails being provided with compression pads.

[0033] It is easy to understand that the above provides specific implementations of the fence and the collection groove, the strip-shaped rubber profile adapts to the set path through the bendable characteristics, blocks the gap between it and the adit wall through the elastic deformation characteristics and maintains a certain blocking pressure, reduces the amount of seepage water in the gap between the fence and the adit wall, the compression nails are used to complete the fixation of the fence and the collection groove on the adit wall, and the compression pads are used to increase the acting area of the compression nails on the fence and the collection groove, and to ensure that the fence and the collection groove are reliably fixed on the adit wall. In specific applications, when the amount of seepage water in the gap between the fence and the collection groove and the adit wall exceeds the allowed range, the water sealing performance can be improved by setting foaming materials in the gap.

[0034] In one specific embodiment, it further comprises a drainage pipe for plugging into the joint gap, and the drainage pipe is used to drain the seepage water from the seepage point to the flow measuring device or the water quality characteristic detection device.

[0035] In the present scheme, the drainage pipe is used as a seepage water drainage device, and is specifically used to be inserted into the joint gap to drain the seepage water from the inside of the joint gap to the flow measuring device or the water quality characteristic detection device. For the adit with a large number of seepage points on the joint, such a seepage water drainage method can greatly reduce the seepage water area on the joint, and compared with obtaining seepage water from the outside of the joint, such a method can improve the collection rate of seepage water in the case of simpler system structure and simpler process.

[0036] The present application has the following beneficial effects:

[0037] The present scheme carries out regionalized seepage water characteristic measurement according to the joint characteristics of the adit surface, which can not only obtain the development of fractures and faults in the surrounding rock mass as a whole, but also distinguish the fractures and faults in the surrounding rock mass, provide more detailed seepage water characteristic data support for rock mass quality evaluation, and thus achieve the purpose of promoting the accurate acquisition of the development state of faults and fractures in the rock mass in the dam site area. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 This is a flow chart of a specific embodiment of the method for evaluating rock mass quality in the dam site area of ​​a hydropower station described in this solution;

[0039] Figure 2 This is a system structure diagram of a specific embodiment of the system for evaluating rock mass quality in the dam site area of ​​a hydropower station described in this solution;

[0040] Figure 3 This is a structural diagram of a specific embodiment of the enclosure described in this solution;

[0041] Figure 4 This is a structural schematic diagram of a specific embodiment of the collection tank described in this solution;

[0042] Figure 5 This is a schematic diagram of a specific embodiment of a flow measurement device including a water storage tank described in this solution. Reference numerals in the accompanying figures are: 1. Flow measurement device; 2. Water quality characteristic detection device; 3. Data processing module; 4. Enclosure; 5. Pressing pins; 6. Pressing pad; 7. Collection tank; 8. Water storage tank; 9. Weighing device; 10. Conversion module. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments:

[0044] Example 1:

[0045] like Figures 1-5 The provided method for evaluating the rock mass quality of a hydropower station dam site area evaluates the development of rock joints based on the seepage water characteristics of the adit in the dam site area, thereby obtaining the rock mass quality of the dam site area. In this method, the seepage water characteristics of the adit are obtained by setting a seepage water detection system in the adit, and the method includes the following steps:

[0046] S1. Based on the joint characteristics of the rock mass adit wall in the dam site area, a barrier 4 is used to divide the adit wall into several sub-areas. The barrier 4 serves as a water-blocking wall between the sub-areas. Joints in the same sub-area appear to be interconnected, while joints in different sub-areas appear to be disconnected.

[0047] S2. Using a seepage water detection system to obtain seepage water characteristics of each sub-area, the seepage water characteristics including the seepage water flow rate at each moment during the detection period, and obtaining a seepage water flow rate curve for each sub-area based on the seepage water flow rate. The seepage water characteristics also include water quality characteristics of the seepage water at a set moment during the detection period, the water quality characteristics including the content characteristics of target ion components in the seepage water and / or the pH characteristics of the seepage water, and fitting a seepage water quality characteristic curve for each sub-area based on the water quality characteristics;

[0048] S3, obtaining the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region according to the seepage water flow curve and the seepage water quality characteristic curve;

[0049] S4, for the sub-regions with the same seepage water flow variation law and the seepage water quality characteristic variation law, the sub-regions are identified as the covered joints with internal connectivity, and the covered joints belong to the same continuous joint; for the sub-regions with different seepage water flow variation law and the seepage water quality characteristic variation law, the sub-regions are identified as the covered joints with mutual disconnection.

[0050] The method provided above evaluates the joint development of rock mass by the adit seepage water characteristics of dam site area, so as to obtain the rock mass quality related to hydrogeology of dam site area, which is an evaluation means based on seepage water measurement. The difference from the existing rock mass quality evaluation is that the existing water pressure test means and seepage water measurement analysis means only take the adit or the selected rock mass as a whole as the seepage evaluation object, which can evaluate the overall water permeability of the object, but for the complex address structure, it cannot well distinguish the water permeability of different joints on the object, and cannot accurately distinguish the fault and fracture development state of different rock masses in dam site area. The specific evaluation method of the present scheme is as follows: first, the apparent characteristics of the joints on the adit wall are used to divide the mutually connected joints into the same sub-region and the mutually disconnected joints into different sub-regions, and the different sub-regions are isolated by the enclosure 4. On this basis, the seepage water characteristics of each sub-region are used, and the seepage water flow curve and the seepage water quality characteristic curve are obtained through the seepage water flow and the seepage water quality. Then, the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region are analyzed, and the sub-regions with the same seepage water flow variation law and the seepage water quality characteristic variation law are identified as the covered joints with internal connectivity, and the sub-regions with different seepage water flow variation law and the seepage water quality characteristic variation law are identified as the covered joints with different joints, which have the characteristics of mutual disconnection.

[0051] Based on the above, for each area of the adit covered by the seepage water detection system, the present scheme determines whether the seepage water of these areas comes from the same seepage path through the seepage water characteristics, for example, for the seepage water characteristics detected by different seepage points, when these seepage points have the same seepage water source, although the seepage point position distribution will cause obvious flow changes not at the same time, but from the seepage water flow change law obtained from each sub-area, it can be found that different sub-areas have similar flow change law at different times, while different fractures and faults independently developed in the rock mass do not have such characteristics, on the other hand, for the water quality characteristics, because the seepage water from different fractures and faults has different phreatic fractures and seepage paths, the difference in phreatic storage environment and the difference in the upper sediment of the path will cause the seepage water from different fractures and faults to have different water quality characteristics, therefore, based on this concept, the present scheme carries out regional seepage water characteristic measurement according to the joint characteristics of the adit surface, which not only can obtain the fracture and fault development of the surrounding rock mass as a whole, but also can distinguish the fractures and faults on the surrounding rock mass, providing more detailed seepage water characteristic data support for rock mass quality evaluation, so as to achieve the purpose of promoting the accurate acquisition of the fracture and fault development state of the rock mass in the dam site area.

[0052] More detailed schemes are as follows: in the step S2, the method for obtaining the seepage water flow is to collect the seepage water of the seepage point and guide the seepage water to the flow measuring device 1 to complete the seepage water flow measurement;

[0053] For the seepage water with an estimated flow greater than or equal to a set flow value, the flow measuring device 1 based on the flow meter is used to complete the seepage water flow measurement, and for the seepage water with an estimated flow less than or equal to a set flow value, the flow measuring device 1 including a water storage device is used to complete the seepage water flow measurement, wherein the water storage device includes a water storage tank 8, a weighing device 9 and a conversion module 10, the water storage tank 8 is used to collect the seepage water inflow, the weighing device 9 is used to measure the weight of the water storage tank 8 at each time, and the conversion module 10 is used to convert the measurement result of the weighing device 9 into the flow value of the seepage water inflow.

[0054] In the above scheme, two seepage water flow measurement methods are provided, wherein according to the current seepage water flow of the adit seepage point, for the seepage water with a larger estimated seepage water flow, the flow meter is used to directly measure the seepage water flow, and for the seepage water with a smaller estimated seepage water flow, the method of indirectly measuring the seepage water flow based on the weight measurement is used. In this method, when the seepage water flow is large, the flow meter is used to measure the flow, which not only has the characteristic of simple system configuration, but also has the characteristic of accurate measurement result; while the method of indirectly measuring the flow by weight increases the system complexity, but can ensure the flow measurement accuracy under small seepage water flow.

[0055] More detailed scheme is: for the water tank 8 is configured with a solenoid valve drain pipe, when the need for water quality characteristics of this part of the seepage water to obtain, solenoid valve open, from the drain pipe for water quality characteristics of the sample, when the seepage water in the water tank 8 accumulation to set weight, solenoid valve open, from the drain pipe discharge original seepage water.

[0056] More detailed scheme is: for the seepage water seepage point located in the side and top of the tunnel, according to the seepage water seepage form, for the seepage water after the wall flow, using fixed in the tunnel wall and located below the seepage point collection tank 7 collection seepage water, and through the pipeline will be collected by collection tank 7 seepage water drainage to flow measuring device 1 complete seepage water flow measurement; for the seepage water after the drop or jet flow, using fixed in the tunnel wall or support on the tunnel floor of the receiving cover to collect seepage water, and through the pipeline will be collected by the receiving cover seepage water drainage to flow measuring device 1 complete seepage water flow measurement.

[0057] In the above scheme, a method for collecting seepage water according to the specific seepage form is provided, which is: using collection tank 7 to collect seepage water after wall flow, using receiving cover to collect seepage water after drop or jet flow, so as to reduce the seepage water collection omission as far as possible in the convenient implementation range, which is beneficial to the seepage water characteristic acquisition. Further, after the seepage water at the seepage point is collected by the collection tank 7 and the receiving cover, the seepage water in a single sub area can be drained to the flow measuring device 1 and the water quality characteristic detection device 2 by using pipe section, drainage groove, convergence groove, etc. When it is determined that the joints on the different sub areas divided in advance belong to the joints under the same crack or fault through the seepage water characteristics, a single flow measuring device 1 and a single water quality characteristic detection device 2 can be used to serve two or more sub areas, so as to simplify the structure of the seepage water detection system in the subsequent process, optimize the use efficiency of the flow measuring device 1 and the water quality characteristic detection device 2, and reduce the data amount in the later stage.

[0058] More detailed scheme is: for the joint with the apparent characteristics of mutual communication and having multiple seepage points, using the gap sealing material to seal the seepage points with relatively small flow, and collecting the seepage water from the remaining seepage points.

[0059] In the above scheme, for the joint with more seepage points on a single sub-area, the method of using gap plugging material to plug part of the small flow seepage points is adopted, so as to improve the collection rate of seepage water and simplify the structure of the seepage water detection system. The gap plugging material can use common building construction water plugging material, but in specific application, the seepage water characteristic evaluation online measurement duration is long, and during the online measurement time period, there are conditions of obvious changes of joints due to stress release of rock mass, and there are conditions of reserved seepage point plugging and new seepage points after intervention of seepage points. The preferred use is to investigate the current seepage points during the online measurement time period, to adjust the seepage water collection scheme accordingly, and to obtain accurate seepage water characteristics in the long term.

[0060] More detailed schemes are that the target ions include one or more of sulfate ions, carbonate ions, bicarbonate ions, magnesium ions and calcium ions, and when the content characteristics are detected, the set time is the time when the seepage water detection system samples according to the set target ion composition sampling frequency.

[0061] In the above scheme, the selected target ions are not only common ion components in seepage water, but also factors that need to be considered in the later construction of the dam. Therefore, such water quality characteristics not only distinguish rock mass fractures and faults, but also provide a reference for the later construction of the dam.

[0062] More detailed schemes are that when the seepage water cannot obtain extractable flow characteristics and water quality characteristics according to the natural rainfall in the dam site area, artificial simulated rainfall is provided for the rock-soil above the flat ridge according to the natural rainfall records of the dam site area in previous years, wherein the rainfall amount of the artificial simulated rainfall matches the rainfall amount of the current season in previous years.

[0063] In the above scheme, when the current seepage water seepage condition cannot meet the seepage water characteristic evaluation, the artificial intervention method is used to obtain seepage water in the flat ridge. Further, when the artificial intervention is performed, the rainfall amount of the current season is obtained from the natural rainfall records of previous years according to the current season, and the artificial rainfall amount is equivalent to the rainfall amount of the current season in previous years. This not only ensures the safety of the rock mass quality evaluation process, but also obtains the real influence of local meteorological conditions on the hydrogeological conditions of the rock mass by simulating the local hydrological conditions.

[0064] The present scheme also relates to a system for evaluating the quality of rock mass in a dam site area of a hydropower station, which is used to implement the method for evaluating the quality of rock mass in a dam site area of a hydropower station as described above.

[0065] The system includes a flow measuring device 1 for obtaining the seepage water flow.

[0066] The system comprises a water quality characteristic detection device 2 for obtaining water quality characteristics of the seepage water;

[0067] The system comprises a data processing module 3 for statistically or fittingly obtaining seepage water flow curves and seepage water quality characteristic curves of each sub-region, and obtaining seepage water flow variation laws and seepage water quality characteristic variation laws of each sub-region, and judging actual connection relationships of joints covered by each sub-region according to the seepage water flow variation laws and the seepage water quality characteristic variation laws.

[0068] It is easy to understand that the system is used to realize the method proposed above, and in use, the system automatically completes seepage water flow acquisition, water quality characteristic acquisition, construction of seepage water flow curves and seepage water quality characteristic curves, obtaining of seepage water flow variation laws and seepage water quality characteristic variation laws, and discrimination of whether joints covered by each sub-region are actually connected, to realize automatic rock mass quality evaluation in dam site area based on joint development of rock mass.

[0069] More detailed schemes are that the flow measuring device 1 comprises a flow measuring device 1 based on a flow meter, and the flow measuring device 1 further comprises a flow measuring device 1 with a water storage tank 8, a weighing device 9, and a conversion module 10, wherein the water storage tank 8 is used to collect seepage water, the weighing device 9 is used to measure the weight of the water storage tank 8 at each time, and the conversion module 10 is used to convert the measurement result of the weighing device 9 into a flow value of seepage water.

[0070] It is easy to understand that the scheme provides differentiated flow measuring devices 1, so that users can select the used flow measuring device 1 according to the current seepage water flow, from the perspective of facilitating implementation and accurately obtaining seepage water flow.

[0071] More detailed schemes are that the system further comprises a fence 4 as a water-resisting wall between sub-regions, the fence 4 is a strip-shaped rubber profile with an L-shaped cross section, the system further comprises a collection groove 7 for collecting seepage water from a flat adit wall, the collection groove 7 is a strip-shaped rubber profile with a U-shaped cross section, the fence 4 and the collection groove 7 are provided with compression nails 5 for fixing them on the flat adit wall, and the compression nail 5 is provided with a compression pad 6 on a nail cap.

[0072] It is easy to understand that the above provides specific fence 4 and collection groove 7 implementation, the strip-shaped rubber profile is adapted to the set path by the bendable property, the gap between the strip-shaped rubber profile and the adit wall is sealed by the elastic deformation property and a certain sealing pressure is maintained, the amount of water seepage between the strip-shaped rubber profile and the adit wall is reduced, the pressing nails 5 are used to complete the fixation of the fence 4 and the collection groove 7 on the adit wall, the pressing pads 6 are used to increase the acting area of the pressing nails 5 on the fence 4 and the collection groove 7, and the reliable fixation of the fence 4 and the collection groove 7 on the adit wall is ensured. In specific application, when the amount of water seepage between the fence 4 and the collection groove 7 and the adit wall exceeds the allowable range, the water sealing performance can be improved by setting the foaming material in the gap.

[0073] A more detailed scheme is that the drainage pipe for being inserted into the joint gap is further included, and the drainage pipe is used to drain the seepage water of the seepage point to the flow measuring device 1 or the water quality characteristic detection device 2.

[0074] In the scheme, the drainage pipe is used as the drainage device of the seepage water, is specifically used to be inserted into the joint gap, and is used to drain the seepage water from the inside of the joint gap to the flow measuring device 1 or the water quality characteristic detection device 2. For the adit with a large number of seepage points on the joint, such a seepage water drainage mode can greatly reduce the seepage area on the joint, and compared with obtaining the seepage water from the outside of the joint, such a mode can improve the collection rate of the seepage water in the case of simpler system structure and simpler process.

[0075] The above is a further detailed description of the present application in combination with the specific preferred embodiments, and the specific embodiments of the present application cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the present application belongs, other embodiments obtained without departing from the technical scheme of the present application should be included in the protection scope of the present application.

Claims

1. A method for evaluating rock mass quality in a dam site area, the method for evaluating rock mass quality in a dam site area obtains rock mass quality in the dam site area by evaluating joint development of the rock mass through water seepage characteristics of a adit in the dam site area, and in the method, the water seepage characteristics of the adit are obtained by setting a water seepage detection system in the adit, and the method is characterized in that, The method comprises the following steps: S1, according to the joint characteristics of the rock mass and the wall of the adit in the dam site area, a barrier (4) is used to divide the wall of the adit into several sub-regions, the barrier (4) is used as a waterproof wall between the sub-regions, the joints in the same sub-region have the apparent characteristics of mutual connection, and the joints in different sub-regions have the apparent characteristics of mutual disconnection; S2, a seepage water detection system is used to obtain the seepage water characteristics of each sub-region, the seepage water characteristics include the seepage water flow at each time during the detection, and the seepage water flow curve of each sub-region is obtained according to the seepage water flow, the seepage water characteristics also include the water quality characteristics of the seepage water at the set time during the detection, the water quality characteristics are the content characteristics of the target ion component in the seepage water and / or the PH value characteristics of the seepage water, and the seepage water quality characteristic curve of each sub-region is fitted according to the water quality characteristics; S3, according to the seepage water flow curve and the seepage water quality characteristic curve, the seepage water flow change rule and the seepage water quality characteristic change rule of each sub-region are obtained; S4, for the sub-regions with the same seepage water flow change rule and the same seepage water quality characteristic change rule, the covered joints are identified as having internal connectivity, the covered joints belong to the same continuous joint, and for the sub-regions with different seepage water flow change rules and different seepage water quality characteristic change rules, the covered joints are identified as being disconnected joints.

2. The method according to claim 1, characterized in that, In the step S2, the method for obtaining the seepage water flow is that the seepage water of the seepage point is collected and is introduced into the flow measuring device (1) to complete the seepage water flow measurement; For the seepage water with the flow greater than or equal to the set flow value, the flow measuring device (1) based on the flow meter is used to complete the seepage water flow measurement, and for the seepage water with the flow less than or equal to the set flow value, the flow measuring device (1) including a water storage device is used to complete the seepage water flow measurement, wherein the water storage device includes a water storage tank (8), further includes a weighing device (9) and a conversion module (10), the water storage tank (8) is used to collect the seepage water, the weighing device (9) is used to measure the weight of the water storage tank (8) at each time, and the conversion module (10) is used to convert the measurement result of the weighing device (9) into the flow value of the seepage water.

3. The method according to claim 2, characterized in that, For the seepage water seepage points located on the side and top of the adit, according to the seepage form of the seepage water, for the seepage water flowing along the wall after seepage, a collection groove (7) fixed on the wall of the adit and located below the seepage point is used to collect the seepage water, and the seepage water collected by the collection groove (7) is introduced into the flow measuring device (1) through a pipeline to complete the seepage water flow measurement; for the seepage water dripping or jetting after seepage, a receiving cover fixed on the wall of the adit or supported on the ground of the adit is used to collect the seepage water, and the seepage water collected by the receiving cover is introduced into the flow measuring device (1) through a pipeline to complete the seepage water flow measurement.

4. The method according to any one of claims 2 to 3, characterized in that, For the joints with the apparent characteristics of mutual connection and multiple seepage points, a crack sealing material is used to seal the seepage points with relatively small flow, and the seepage water of the seepage points is collected from the remaining seepage points.

5. The method according to claim 1, characterized in that, The target ions include one or more of sulfate ions, carbonate ions, bicarbonate ions, magnesium ions, and calcium ions, and the set time is a time at which the seepage water detection system performs seepage water sampling according to a set target ion component sampling frequency.

6. The method according to claim 1, characterized in that, When seepage water with extractable flow characteristics and water quality characteristics cannot be obtained according to natural rainfall in the dam site area, artificial simulated rainfall is provided for the rock-soil above the flat tunnel according to natural rainfall records of the dam site area in previous years, wherein the rainfall amount of the artificial simulated rainfall matches the rainfall amount of the current season in previous years.

7. A system for rock mass quality evaluation in dam site area of a hydropower station, characterized in that, The system is used to implement the rock mass quality evaluation method of the dam site area of the hydropower station according to any one of claims 1-6; The system includes a flow measuring device (1) for obtaining the seepage water flow; The system includes a water quality characteristic detection device (2) for obtaining the water quality characteristics of the seepage water; The system includes a data processing module (3) for statistically or fittingly obtaining the seepage water flow curve and the seepage water quality characteristic curve of each sub-region, obtaining the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region, and judging the actual connection relationship of the joint covered by each sub-region according to the seepage water flow variation law and the seepage water quality characteristic variation law of each sub-region.

8. The system of claim 7, wherein, The flow measuring device (1) includes a flow measuring device (1) based on a flow meter, and the flow measuring device (1) further includes a flow measuring device (1) having a water storage tank (8), a weighing device (9), and a conversion module (10), wherein the water storage tank (8) is used to collect seepage water, the weighing device (9) is used to measure the weight of the water storage tank (8) at each time, and the conversion module (10) is used to convert the measurement result of the weighing device (9) into a flow value of the seepage water.

9. The system of claim 7, wherein, The system further includes a fence (4) as a waterproof wall between sub-regions, the fence (4) is a strip-shaped rubber profile with an L-shaped cross section, and the system further includes a collection groove (7) for collecting seepage water from the wall of the flat tunnel, the collection groove (7) is a strip-shaped rubber profile with a U-shaped cross section, and the fence (4) and the collection groove (7) are provided with a compression nail (5) for fixing them on the wall of the flat tunnel, and a compression pad (6) is arranged on the nail cap of the compression nail (5).

10. The system of claim 7, wherein, The system further includes a drainage pipe for plugging into the joint gap, and the drainage pipe is used to drain the seepage water of the seepage point to the flow measuring device (1) or the water quality characteristic detection device (2). The system further includes a drainage pipe for plugging into the joint gap, and the drainage pipe is used to drain the seepage water of the seepage point to the flow measuring device (1) or the water quality characteristic detection device (2).

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