A method for optimizing active measuring points of a casing method stress test by fusing multi-source uncertain constraints and related equipment

Abstract

The application discloses a method for optimizing active measuring points of casing annulus pressure release method for ground stress testing by fusing multi-source uncertain constraints and related equipment. The method for optimizing active measuring points of casing annulus pressure release method for ground stress testing by fusing multi-source uncertain constraints can avoid unreasonable influence of auxiliary information with unclear sources, unmatched applicable depth or obvious conflict with other information on current measuring point ground stress results, and give active measuring point optimization suggestion information such as current measuring point retest, adjacent depth encrypted measuring point, different direction supplementary drilling or auxiliary test review according to measuring point reliability level and uncertainty source, so as to provide optimization suggestion for current measuring point testing work for field testers, and be beneficial to field testers to improve the current measuring point testing work. The application is widely applied in the fields of rock mass ground stress measurement and measurement data processing technology.

Description

Technical Field

[0001] This invention relates to the field of rock mass in-situ stress measurement and measurement data processing technology, and in particular to an active measurement point optimization method and related equipment for in-situ stress testing using the core-sleeve removal method that integrates multi-source uncertain constraints. Background Technology

[0002] In-situ stress is a crucial parameter for the design and stability evaluation of underground caverns, tunnels, mine roadways, underground water conservancy and hydropower projects, slope engineering, and underground energy projects. The core-strain stress relief method is a commonly used approach in in-situ in-situ stress testing. This method typically involves installing strain gauges or strain measurement probes inside the borehole. Through core sampling, the original stress in the rock mass near the measuring point is released, and the release amount of strain channels in different directions is recorded. Combined with parameters such as borehole azimuth, borehole dip angle, strain gauge arrangement parameters, rock elastic modulus, and Poisson's ratio, the three-dimensional in-situ stress state at the measuring point is inverted.

[0003] In practical engineering, the geostress results obtained from a single core measuring point are often affected by factors such as rock mass heterogeneity, structural plane development, borehole attitude error, dispersion of rock elastic parameters, test depth location, and field construction conditions. Therefore, the inversion results from the current measuring point should not only represent a definite geostress value, but also include the reliable range of the magnitude and direction of the principal stresses, as well as the main sources of uncertainty in the results. If only a single geostress result is output without assessing its consistency with neighboring measuring points and other field data, it is difficult to determine whether the current measuring point result can be directly used for engineering analysis. Summary of the Invention

[0004] To address at least one of the aforementioned technical problems, the present invention aims to provide an optimization method and related equipment for active measuring points in geostress testing using the core-sleeve removal method, which integrates multi-source uncertain constraints.

[0005] On one hand, embodiments of the present invention include an optimization method for active measuring points in geostress testing using the core-removal method that integrates multi-source uncertain constraints. This method includes the following steps: Obtain the stress relief test data of the core sleeve at the current measuring point; Multiple auxiliary information corresponding to the current measurement point is acquired from multiple sources; Based on the core stress relief test data, calculate the geostress benchmark result and its confidence range corresponding to the current measuring point; Convert the auxiliary information into auxiliary constraint terms; Calculate the consistency index between the auxiliary information and the geostress benchmark results; Based on the consistency index, the reliability of each piece of auxiliary information is updated to obtain the updated reliability. Based on the updated reliability, the multi-source fusion evaluation result of the geostress corresponding to the current measuring point is obtained; Based on the geostress benchmark results, the consistency index, and the geostress multi-source fusion evaluation results, identify the uncertainty sources corresponding to the current measuring point; The reliability level is determined based on the multi-source geostress fusion evaluation results, and active measurement point optimization suggestions are generated based on the reliability level and the uncertainty source information.

[0006] Furthermore, the step of calculating the geostress benchmark result and its confidence range corresponding to the current measuring point based on the core stress relief test data includes: Based on the stress relief test data of the core sleeve, determine the strain-stress response matrix. and the three-dimensional geostress tensor component vector ; According to the formula

[0007] Determine the observed strain vector ;in, This is the observation error term; According to the strain-stress response matrix Three-dimensional geostress tensor component vector and the observed strain vector The constraint effect of the stress relief test data of the core sleeve on the in-situ stress results was determined. ; Based on the three-dimensional geostress tensor component vector Determine the a priori range constraints of the ground stress foundation. ; According to the formula

[0008] Determine the reference ground stress distribution corresponding to the current measuring point. ; According to the reference geostress distribution The three-dimensional geostress components, principal stress magnitudes, principal stress directions, and corresponding confidence ranges corresponding to the current measuring point are calculated; wherein, the three-dimensional geostress components, the principal stress magnitudes, and the principal stress directions constitute the geostress reference result.

[0009] Further, the step of converting the auxiliary information into auxiliary constraint terms includes: For any of the aforementioned auxiliary information, the information is classified according to the geostress characteristics reflected by the auxiliary information to determine the corresponding classification category; the classification categories include direction category, stress magnitude category, depth trend category, and result impact category; For the The aforementioned auxiliary information, according to the formula

[0010] Determine the first The auxiliary constraint item corresponding to the auxiliary information. Among them, when the first The aforementioned auxiliary information belongs to the direction category. Indicates the first The difference in principal stress direction corresponding to the auxiliary information; when the first The aforementioned auxiliary information belongs to the stress magnitude category. Indicates the first The differences in principal stress magnitude, stress components, or principal stress difference corresponding to the auxiliary information mentioned; when the first... The aforementioned auxiliary information belongs to the deep trend category. This indicates the difference between the geostress benchmark result corresponding to the current measuring point and the depth variation trend of adjacent measuring points; No. The error scale corresponding to each of the auxiliary information.

[0011] Furthermore, the consistency index between the calculated auxiliary information and the geostress benchmark result includes: When the The aforementioned auxiliary information belongs to the direction category, according to the formula...

[0012] Determine the equivalent directional difference ;in, For the first The direction provided by the aforementioned auxiliary information. The representative value of the principal stress direction obtained by inverting the geostress benchmark results; according to the formula

[0013] Determine the first The directional consistency index corresponding to the auxiliary information. ;in, The uncertainty scale for the principal stress direction obtained by inverting the aforementioned geostress benchmark results is given by [the relevant data point]. For the first The interpretation error scale of the aforementioned auxiliary information; When the The aforementioned auxiliary information belongs to the stress magnitude category, according to the formula...

[0014] Determine the first Stress magnitude consistency index corresponding to the auxiliary information. ;in, This represents the stress magnitude, stress components, or principal stress difference representative value corresponding to the aforementioned geostress benchmark results. For the first The corresponding value given by the aforementioned auxiliary information. This serves as the uncertainty scale for the corresponding stress quantity in the geostress benchmark results. For the first The error scale of the auxiliary information; When the The aforementioned auxiliary information belongs to the deep trend category, according to the formula...

[0015] Determine the first Consistency index of depth change trend corresponding to the auxiliary information ;in, For the first The depth at which the aforementioned auxiliary information is located. For the current measurement point, the adjacent reliable measurement points are at depth The trend forecast value given here, For the first The corresponding value given by the aforementioned auxiliary information. The trend prediction value The uncertainty scale For the first The error scale of the auxiliary information; When the The aforementioned auxiliary information belongs to the category of result impact, according to the formula.

[0016] Determine the first The fusion result impact index corresponding to the auxiliary information mentioned above ;in, Indicates not to include the aforementioned first... The representative value of the geostress result obtained when using auxiliary information. Indicates the addition of the first The representative value of the geostress result obtained after considering auxiliary information. As a reference scale for the corresponding changes in results Using the aforementioned directional consistency index The stress magnitude consistency index The consistency index of the depth change trend And the fusion result impact index The set of consistency indicators .

[0017] Further, updating the reliability of each piece of auxiliary information based on the consistency index to obtain updated reliability includes: For the The auxiliary information sets the initial reliability. ; Set the directional consistency index Corresponding weights The stress magnitude consistency index Corresponding weights The consistency index of the depth change trend Corresponding weights And the fusion result impact index Corresponding weights ; According to the formula

[0018] Determine the first The degree of overall contradiction corresponding to each of the aforementioned auxiliary information ; According to the formula

[0019] Determine the first The update reliability corresponding to each of the auxiliary information .

[0020] Furthermore, updating the reliability of each piece of auxiliary information based on the consistency index to obtain the updated reliability further includes: Set a preset reliability threshold. ; when At that time, determine the first The aforementioned auxiliary information participates in the evaluation process of the multi-source fusion evaluation results of geostress; when At that time, determine the first The aforementioned auxiliary information is to be verified and is not included in the evaluation process of the multi-source geostress fusion evaluation results.

[0021] Further, obtaining the multi-source fusion evaluation result of the geostress corresponding to the current measuring point based on the updated reliability includes: According to the formula

[0022] Determine the multi-source fusion evaluation results of the geostress. ;in, The constraint effect of the stress relief test data on the geostress results is explained. For the a priori range constraints of the ground stress foundation, For the first The auxiliary constraint terms corresponding to each of the aforementioned auxiliary information. For the first The update reliability corresponding to each of the aforementioned auxiliary information. The number of auxiliary information items involved in the judgment.

[0023] Further, the step of generating active measurement point optimization suggestion information based on the reliability level and the uncertainty source information includes: When the reliability level is lower than the threshold, candidate solutions are determined based on the uncertainty source information; the candidate solutions include one or more of the following: retesting the current measuring point, densifying measuring points at nearby depths, supplementing boreholes in different orientations, borehole wall imaging verification, borehole television verification, core pancake recording verification, and supplementary measurement of rock elastic parameters. When there are multiple candidate solutions, prioritize each candidate solution. Based on the candidate scheme with the highest priority, the active measurement point optimization suggestion information is generated.

[0024] On the other hand, embodiments of the present invention also include a computer device, including a memory and a processor, the memory for storing at least one program, and the processor for loading at least one program to execute the active measurement point optimization method for stress testing using the core-removal method that incorporates multi-source uncertain constraints in the embodiments.

[0025] On the other hand, embodiments of the present invention also include a computer-readable storage medium storing a processor-executable program, which, when executed by a processor, is used to perform the active measurement point optimization method for stress testing using the core-removal method that incorporates multi-source uncertain constraints in the embodiments.

[0026] The beneficial effects of this invention are as follows: The active measurement point optimization method for geostress testing using the core-removal method that integrates multi-source uncertain constraints in the embodiments can avoid the unreasonable influence of auxiliary information with unclear sources, mismatched applicable depths, or obvious conflicts with other information on the current measurement point's geostress results. Based on the measurement point's reliability level and uncertainty source, it provides active measurement point optimization suggestions such as retesting the current measurement point, densifying measurement points at nearby depths, supplementing boreholes in different orientations, or auxiliary test verification. This provides on-site testing personnel with optimization suggestions for the testing work at the current measurement point, which is beneficial for on-site testing personnel to improve the testing work at the current measurement point. Attached Figure Description

[0027] Figure 1 This is a schematic diagram illustrating the steps of the active measuring point optimization method for geostress testing using the core-sleeve removal method, which incorporates multi-source uncertain constraints, as shown in the embodiment. Figure 2 This is a schematic diagram illustrating the principle of obtaining the geostress benchmark result corresponding to the current measuring point in the embodiment. Figure 3 This is a schematic diagram illustrating the spatial relationship between the current measuring point and other measuring points in the embodiment. Figure 4 This is a schematic diagram illustrating the consistency judgment and reliability update of auxiliary information in the embodiment; Figure 5 This is a schematic diagram illustrating the information on measurement point reliability classification, uncertainty source identification, and active measurement point optimization suggestions in the embodiment. Detailed Implementation

[0028] When using the core-relief method for geostress testing, in addition to obtaining the core-relief test results at the current measuring point, the field often yields geostress results from adjacent measuring points, borehole fracture azimuth, borehole induced tension fracture azimuth, core disc formation characteristics, borehole wall imaging interpretation results, borehole television data, and other independent geostress test results. This data is crucial for determining the direction of principal stress, the state of high geostress, and the trend of stress variation with depth. For example, adjacent measuring points within the same borehole can reflect the trend of geostress variation along the depth direction; nearby borehole measuring points can reflect the stress state in the vicinity; the azimuth of borehole fractures and induced tension fractures can provide a reference for the direction of horizontal principal stress; and core disc formation records can reflect the possibility of high geostress or a large principal stress difference.

[0029] However, different auxiliary information sources vary in their applicable depth range, spatial location, clarity of identification, and error range. Some borehole wall fracture interpretation results may be affected by borehole wall quality or imaging clarity; some results from neighboring measuring points may not be located in the same geological structure as the current measuring point; and some core cake phenomena may be affected by lithology, structural planes, or core disturbance. Therefore, directly incorporating the aforementioned auxiliary information as fixed and reliable constraints into the current measuring point's geostress evaluation process may lead to the overuse of erroneous or inapplicable auxiliary information, causing the current measuring point's geostress evaluation results to deviate from the range supported by its own test data and the trends in adjacent depths.

[0030] In summary, the processing of core stress relief test results typically has the following shortcomings: (1) Most methods focus on providing the geostress estimate at the current measuring point, but do not adequately consider the confidence range of the principal stress magnitude and direction, the source of uncertainty, and the evaluation of the availability of the results; (2) Auxiliary data such as adjacent measuring points, borehole fractures, induced tension fractures, core pancakes, borehole wall imaging and borehole television are mostly used as qualitative interpretation basis, lacking unified data archives, error range and applicable depth records; (3) There may be contradictions between auxiliary information from different sources. For example, the trend of adjacent measuring points is inconsistent with the interpretation direction of the borehole wall, and the current measuring point results are significantly different from the results of nearby boreholes. Existing methods lack quantitative judgment on the consistency of such multi-source information. (4) Incorrect, unclear, or mismatched auxiliary information may be directly used as reliable constraints, which may cause unreasonable impact on the current geostress evaluation results at the measuring points; (5) Existing results are usually only used to evaluate the current measuring point, and it is difficult to further determine whether the current measuring point needs to be re-measured, the measuring point needs to be densified at the adjacent depth, the borehole needs to be supplemented in different orientations, the borehole wall imaging needs to be verified, the borehole television needs to be verified, the core pancake record needs to be verified, or the rock mechanical parameters need to be supplemented.

[0031] Bayesian or probabilistic inversion methods can provide a certain degree of confidence interval or uncertainty range for geostress results. However, simply merging the current measurement results with auxiliary engineering data makes it difficult to determine the consistency between different information sources, and also difficult to identify which auxiliary information should be retained, have reduced influence, or be marked as information to be verified. Therefore, a reliability evaluation method for geostress test results using the core stress relief method is needed. Based on the current benchmark inversion results, this method should further integrate auxiliary information such as neighboring measurement points, borehole fracturing, induced tension fractures, core disc formation, and borehole wall imaging to determine the degree of consistency between these information and the current measurement results and the adjacent depth variation trend. The reliability of various auxiliary information should be updated, and suggestions for retesting, densifying measurement points, or supplementing tests should be given based on the reliability level of the measurement points and the source of uncertainty. This will improve the pertinence of the evaluation of core stress test results and subsequent measurement point layout decisions.

[0032] To address the problems in the above-mentioned stress testing using the core-stripping stress relief method, such as difficulty in judging the reliability of single measurement point results, potential contradictions between auxiliary information, easy overuse of erroneous auxiliary information, and difficulty in guiding subsequent retesting and measurement point layout, this embodiment provides an active measurement point optimization method for stress testing using the core-stripping stress relief method that integrates multi-source uncertain constraints, based on the principles underlying these technical problems.

[0033] Reference Figure 1 The optimization method for active measuring points in geostress testing using the core-sleeve removal method, which integrates multi-source uncertain constraints, includes the following steps: S1. Obtain the stress relief test data of the core sleeve at the current measuring point; S2. Acquire multiple auxiliary information corresponding to the current measurement point from multiple sources; S3. Based on the core stress relief test data, calculate the geostress benchmark result and its confidence range corresponding to the current measuring point; S4. Convert auxiliary information into auxiliary constraint terms; S5. Consistency index between calculation auxiliary information and geostress benchmark results; S6. Update the reliability of each piece of auxiliary information according to the consistency index to obtain the updated reliability; S7. Based on the updated reliability, obtain the multi-source fusion evaluation results of the geostress corresponding to the current measuring point; S8. Based on the geostress benchmark results, consistency index, and geostress multi-source fusion evaluation results, identify the uncertainty sources corresponding to the current measuring point; S9. Determine the reliability level based on the multi-source geostress fusion evaluation results, and generate active measurement point optimization suggestions based on the reliability level and uncertainty source information.

[0034] In step S1, the core stress relief test data of the current measuring point includes the strain release curve of each channel, strain gauge number, strain gauge installation angle, borehole azimuth angle, borehole inclination angle, measuring point depth, hole diameter, core size, rock elastic modulus, Poisson's ratio, test time, sampling frequency, instrument zero point information, and test environment parameters.

[0035] In step S1, a current measuring point data file is established based on the core stress relief test data of the current measuring point. The current measuring point data file includes the measuring point number, borehole number, measuring point spatial location, measuring point depth, test time, coordinate direction, borehole attitude, strain gauge arrangement parameters, rock elastic parameters, strain release data, data units, data source, and test record description. The current measuring point data file is used to calculate the geostress benchmark results corresponding to the current measuring point and its reliability range, and serves as the basis for subsequent consistency judgments of auxiliary information.

[0036] In step S2, auxiliary information refers to other field test, observation, or interpretation data, besides the core stress relief test data of the current measuring point, that can be used to assist in determining the stress state of the current measuring point. When performing step S2, auxiliary information can be obtained from multiple data sources. The obtained auxiliary information includes one or more of the following: stress results from adjacent measuring points, borehole fracture azimuth, borehole induced tension fracture azimuth, core disc formation characteristics, borehole wall imaging interpretation results, borehole television data, and other independent stress test results.

[0037] Among them, the geostress results of adjacent measuring points are used to reflect the magnitude and direction of geostress at adjacent depths or near borehole locations in the same borehole; the borehole fracture azimuth and borehole induced tension fracture azimuth are used to provide reference information on the direction of horizontal principal stress; the core disc formation characteristics are used to reflect the possibility of high geostress state or large principal stress difference; borehole wall imaging and borehole television data are used to verify the identification results of borehole fracture, induced tension fracture and borehole wall structural characteristics.

[0038] In step S2, an auxiliary information file is established for the auxiliary information. The auxiliary information file includes the type of auxiliary information, observed or interpreted value, data source, spatial location, applicable depth range, coordinate direction, time record, identification method, identification reliability, error range, and spatial relationship with the current measuring point. Auxiliary information with unclear sources, ambiguous applicable depth ranges, unclear identification results, or questionable interpretation results is recorded as information awaiting verification, and its initial reliability is reduced during subsequent consistency assessments and reliability updates.

[0039] In step S3, based on the current measuring point data archive established in step S1, the geostress benchmark result and its confidence range corresponding to the current measuring point are calculated. The geostress benchmark result refers to the geostress result obtained solely from the core stress relief test data of the current measuring point, without incorporating auxiliary information such as geostress results from adjacent measuring points, borehole fracture azimuth, borehole induced tensile fracture azimuth, and core disc formation characteristics.

[0040] Specifically, when performing step S3, based on the transformation relationship between the engineering coordinate system, the borehole coordinate system, and the strain gauge local coordinate system, and combined with the borehole azimuth, borehole inclination, strain gauge installation angle, strain gauge spatial arrangement, rock elastic modulus, Poisson's ratio, and core stress relief theory, a strain-stress response relationship between the strain release at the current measuring point and the components of the three-dimensional geostress tensor is established.

[0041] Let the strain-stress response matrix in the stress relief test data of the core at the current measuring point be... The three-dimensional geostress tensor component vector is The observed strain vector is Then we have:

[0042] In the formula, This represents the observation error term. The observed strain vector. It consists of the final released strain or characteristic released strain of each strain channel at the current measuring point. Three-dimensional geostress tensor component vector. Including three normal stress components and three shear stress components, it can be expressed as:

[0043] Without introducing auxiliary information, the strain vector is observed based on the current measuring point. Strain-stress response matrix Based on the feasible range of geostress physics, the geostress benchmark result for the current measuring point is calculated. When using the probabilistic inversion method, the geostress benchmark result for the current measuring point can be expressed as:

[0044] In the formula, This represents the current benchmark stress distribution at the measuring point, used to indicate the possible range of stress obtained solely from the stress relief data of the core casing at the current measuring point. This is to explain the constraint effect of the stress relief data of the current measuring point core on the ground stress results; This serves as a priori or physically feasible constraint for the geostress foundation.

[0045] Based on the baseline geostress distribution, the three-dimensional geostress components, principal stress magnitudes, principal stress directions, and corresponding confidence ranges for the current measuring point are calculated. The confidence ranges include the confidence intervals for principal stress magnitudes, the possible ranges of change in principal stress directions, and the uncertainty ranges for the geostress tensor components. This baseline result is not used as the final multi-source fusion evaluation result, but rather as a reference in subsequent step S5 to determine whether various auxiliary information is consistent with the current measuring point results.

[0046] In step S4, the auxiliary information archive established in step S2 is organized and converted. Auxiliary information from different sources and in different forms is converted into auxiliary constraint information that can be compared with the current geostress benchmark results at the measuring point and can participate in consistency judgment and multi-source fusion evaluation. The auxiliary information includes one or more of the following: geostress results from adjacent measuring points, borehole fracture azimuth, borehole induced tensile fracture azimuth, core disc formation characteristics, borehole wall imaging interpretation results, borehole television data, and other independent geostress test results.

[0047] For each type of auxiliary information, its observed or interpreted value, data source, spatial location, applicable depth range, coordinate direction, error range, recognition reliability, and spatial relationship with the current measuring point are recorded. Based on the geostress characteristics reflected by the auxiliary information, it is converted into directional auxiliary constraints, stress magnitude auxiliary constraints, depth trend auxiliary constraints, or result impact auxiliary constraints.

[0048] For stress results from neighboring measuring points, these results are converted into reference information such as stress components, principal stress magnitudes, principal stress directions, or principal stress differences. The closer the spatial distance and the smaller the depth difference between neighboring measuring points and the current measuring point, and the narrower the reliability range and the more complete the test records of the neighboring measuring points themselves, the higher the initial reliability of the results from those neighboring measuring points. For measuring points within the same borehole located at adjacent depths above and below the current measuring point, they can also be used to establish a reference trend for the variation of in-situ stress with depth.

[0049] For the borehole fracture location and the borehole-induced tension crack location, based on the borehole fracture type, induced tension crack morphology, and field interpretation rules, they are converted into horizontal principal stress direction reference information that can be used for comparison. Since the principal stress direction has 180-degree equivalence, the difference in equivalent directions is used for comparison when subsequently determining whether it is consistent with the principal stress direction at the current measuring point. The clearer the identification of the borehole fracture or induced tension crack, the better the continuity, and the more consistent the different interpretation data, the smaller its error range and the higher its initial reliability; conversely, its initial reliability is reduced or it is marked as information to be verified.

[0050] For core disc formation characteristics, the depth, frequency, thickness, integrity, and continuity of the disc formation are converted into reference information for a high geostress state or a large principal stress difference level. The more continuous the core disc formation, the clearer the characteristics, and the closer it is to the current measurement point depth, the higher its initial reliability. If the disc formation is discontinuous, the lithology changes significantly, or the core disturbance is strong, its initial reliability is reduced, and it is treated as a weak constraint or information to be verified in subsequent consistency assessments.

[0051] Through the above transformation, we obtain the comparison object, error range, and initial reliability corresponding to each type of auxiliary information. For the first... This is supplementary information, which can be further analyzed based on the current ground stress state. Calculate the difference between it and the auxiliary information. This serves as auxiliary constraint information. The auxiliary constraint information is used to construct the auxiliary constraint terms used in step S7. .

[0052] Specifically, no. Auxiliary constraint terms corresponding to each auxiliary information Indicates the current state of geostress. The degree of compatibility with this auxiliary information. When the current geostress state... The more consistent it is with this auxiliary information, the better. The larger the value of , the more significant the difference between the two. The smaller the value, the better. In a preferred embodiment, the difference between the current geostress state and the m-th auxiliary information can be used. and its error scale The auxiliary constraint terms are represented as:

[0053] In the formula, For the current geostress state and the first The amount of difference between auxiliary information This serves as the error scale for the auxiliary information. For direction-type auxiliary information, It can represent the difference in principal stress direction; for auxiliary information such as stress magnitude, It can represent the differences in principal stress magnitude, stress components, or principal stress differences; for depth trend-type auxiliary information, It can represent the difference between the current measurement results and the changing trends at adjacent depths; for core disc formation characteristics, It can represent the difference between the current principal stress difference or high ground stress discrimination quantity and the pie chart indication information.

[0054] In step S5, using the geostress benchmark result and its reliability range corresponding to the current measuring point obtained in step S3 as a reference, consistency indices are calculated item by item for each type of auxiliary constraint information obtained in step S4. The consistency indices include directional consistency indices, stress magnitude consistency indices, depth variation trend consistency indices, and fusion result impact indices, used to determine whether the auxiliary information is consistent with the current measuring point benchmark result, and whether there are any obvious contradictions.

[0055] For auxiliary information belonging to the direction category, let the representative value of the principal stress direction obtained from the reference inversion of the current measuring point be... , No. The direction given by the auxiliary information is Since the principal stress directions are equivalent at 180 degrees, the difference in equivalent directions between them can be expressed as:

[0056] The directional consistency index can be expressed as:

[0057] In the formula, This serves as the scale for the uncertainty in the principal stress direction at the current measuring point. For the first The interpretation error scale for directional auxiliary information. The smaller the value, the better the consistency between the auxiliary information and the current measurement point benchmark result in terms of direction; The larger the value, the more obvious the contradiction between the two directions.

[0058] For auxiliary information belonging to the stress magnitude category, let the representative value of the stress magnitude, stress component, or principal stress difference in the current measurement point reference result be denoted as . , No. The corresponding value given by each piece of auxiliary information is The stress magnitude consistency index can then be expressed as:

[0059] In the formula, This serves as the scale of uncertainty for the corresponding stress in the current measurement point benchmark results. For the first Error scales for each category of auxiliary information. The smaller the value, the closer the stress magnitude or principal stress difference is to each other; The larger the value, the more pronounced the contradiction between the magnitude of stress or the principal stress difference.

[0060] For auxiliary information with a defined depth location belonging to the depth trend category, let the depth change trend obtained by fitting adjacent reliable measurement points be: , No. The depth of each piece of auxiliary information is The magnitude of the stress, stress components, or principal stress difference it provides is: Then the consistency index of depth change trend can be expressed as:

[0061] In the formula, For adjacent reliable measuring points at depth The trend forecast value given here, This serves as a measure of the uncertainty of the predicted value of this trend. For the first Error scale for depth location auxiliary information. The smaller the value, the more closely the auxiliary information matches the trend of geostress variation formed by adjacent depth measuring points; The larger the value, the more significant the difference between the auxiliary information and the trend of depth change.

[0062] Regarding the impact indicators of the fusion results, compare the addition of the first... The degree of change in the geostress results at the current measuring point before and after the first auxiliary information. Assume no auxiliary information is added. The representative value of the geostress result obtained when using auxiliary information is: Join the The representative value of the geostress result obtained after obtaining auxiliary information is: The fusion result impact index can be expressed as:

[0063] In the formula, and It can represent the magnitude, direction, difference between principal stresses, or three-dimensional geostress components. This serves as a reference scale for the corresponding changes in results. The larger the value, the more significant the impact of the auxiliary information on the fusion evaluation results. When the source of the auxiliary information is unclear or contradicts other consistency indicators, its role needs to be reduced or marked as information to be reviewed in subsequent reliability updates.

[0064] Based on the directional consistency index, stress magnitude consistency index, depth change trend consistency index, and fusion result impact index, the first... A set of consistency indicators for auxiliary information:

[0065] In this embodiment, a piece of auxiliary information may belong to multiple classification categories simultaneously, or it may belong to only one classification category. If a piece of auxiliary information does not belong to certain classification categories, then the consistency index corresponding to the classification categories to which the auxiliary information does not belong does not need to be calculated.

[0066] The consistency indicators described above can be used to determine whether various types of auxiliary information are consistent with the current measurement point benchmark results, and to identify situations such as directional inconsistencies, magnitude inconsistencies, depth trend inconsistencies, or abnormal results. These consistency indicators serve as the basis for updating the reliability of each auxiliary information in step S6.

[0067] In step S6, the reliability of each auxiliary information is updated based on the direction consistency index, stress magnitude consistency index, depth change trend consistency index, and fusion result impact index obtained in step S5.

[0068] Let the first The initial reliability of each piece of auxiliary information is: Its value ranges from 0 to 1. The initial reliability can be determined based on the data source, clarity of identification, applicable depth range, spatial location, error range, and completeness of the field record. Auxiliary information with a clear data source, an applicable depth close to the current measuring point, clear identification results, and a small error range has a higher initial reliability; auxiliary information with an unclear source, ambiguous applicable depth, questionable identification results, or a large error range has a lower initial reliability.

[0069] Based on the consistency index obtained in step S5, construct the first... The degree of contradiction among the auxiliary information In a preferred embodiment, the degree of overall contradiction can be expressed as:

[0070] In the formula, As an indicator of directional consistency, As an index of stress consistency, As an indicator of consistency in the trend of deep change. The indicators affecting the fusion results; These are the weighting coefficients for the corresponding indicators. For auxiliary information that is not applicable to a certain type of consistency indicator, this item can be removed from the above formula, and only the applicable indicators should be weighted.

[0071] In this embodiment, if a piece of auxiliary information does not belong to certain classification categories, then the weight coefficient corresponding to the classification category to which the auxiliary information does not belong is 0. For example, if the first... If the first piece of auxiliary information does not belong to the direction category, then the second piece of information... Weight coefficients corresponding to each piece of auxiliary information It is 0.

[0072] Based on the degree of comprehensive contradiction Update # The reliability of auxiliary information. In a preferred embodiment, the updated reliability, i.e., the updated reliability, can be expressed as:

[0073] In the formula, For the first The initial reliability of auxiliary information, To update reliability. The smaller the value, the more consistent the auxiliary information is with the current measurement point benchmark results, the trend of adjacent depth changes, and other multi-source information, and the closer the update reliability is to its initial reliability. The larger the value, the more obvious the contradiction between the auxiliary information and the current measurement point benchmark result or other multi-source information, and the lower the update reliability.

[0074] Auxiliary information with good consistency in direction, stress magnitude, and depth variation trend will retain its role in subsequent fusion evaluation. Auxiliary information with one indicator being too high but others remaining relatively stable will be treated as low-reliability auxiliary information and included in subsequent fusion evaluation. Auxiliary information with multiple significantly high consistency indicators, unclear sources, mismatched applicable depths, or questionable identification results will be marked as information requiring verification.

[0075] Furthermore, it can be based on the update reliability Configure the participation status of auxiliary information. Set the preset reliability threshold to... ,when When this auxiliary information is available, it can be used in subsequent multi-source fusion evaluation; when In this case, the auxiliary information is not used as a reliability constraint in the fusion evaluation, but is only output as information to be verified in the results. For auxiliary information with reliability between high reliability and information to be verified, its role in subsequent fusion evaluation can be reduced, rather than being directly removed.

[0076] The above reliability update process can avoid the overuse of auxiliary information with unclear sources, mismatched applicable depths, or obvious contradictions with the current measurement point benchmark results, and provide updated reliability for the current measurement point geostress multi-source fusion evaluation in step S7.

[0077] In step S7, based on the updated reliability obtained in step S6, the geostress benchmark result corresponding to the current measuring point and the auxiliary information that can participate in the fusion evaluation are used together to evaluate the geostress result of the current measuring point, so as to obtain the multi-source fusion evaluation result of the geostress of the current measuring point.

[0078] In a preferred embodiment, let the stress tensor component vector at the current measuring point be... The current data on stress relief at the measuring point is as follows: The strain-stress response matrix is , No. The auxiliary constraint terms corresponding to each piece of auxiliary information are: The update reliability is The current multi-source fusion evaluation result of geostress at the measuring point can be expressed as:

[0079] In the formula, This represents the current set of core stress relief data at the measuring point and auxiliary information used in the fusion evaluation. To constrain the current core data from the measuring points on the geostress results, Constrained by the physical feasibility range of geostress. The number of auxiliary information items used in the judgment. Reliability of auxiliary information. The higher the level, the stronger the role of the corresponding auxiliary constraint terms in the fusion evaluation; the reliability of auxiliary information The lower the value, the weaker the effect of the corresponding auxiliary constraint. When a piece of auxiliary information is marked as information to be reviewed, it is not used as a reliable constraint in the fusion evaluation, or it is only output as information to illustrate the result.

[0080] Based on the multi-source fusion evaluation results, the magnitude and direction of the three-dimensional geostress components, maximum principal stress, intermediate principal stress, and minimum principal stress at the current measuring point are calculated, and the confidence intervals for principal stress magnitudes, confidence ranges for principal stress directions, and uncertainty ranges for geostress tensor components are given. When two or more principal stresses are close in magnitude, the stability of the principal stress ranking is further determined.

[0081] Furthermore, the reliability of the current geostress results at the measuring point is evaluated based on the current benchmark results' confidence range, auxiliary information consistency index, update reliability, confidence interval width of principal stress magnitudes, dispersion of principal stress directions, and stability of principal stress ordering. Reliability levels include high reliability, relatively reliable, generally reliable, low reliability, and invalid. High reliability indicates a narrow confidence range for the current benchmark results, with auxiliary information largely consistent with the current measuring point results, and stable principal stress magnitudes and directions. Low reliability or invalidity indicates a wide confidence range for the current measuring point results, significant contradictions in auxiliary information, or unstable principal stress magnitudes, directions, and ordering.

[0082] In step S8, based on the current benchmark results, multi-source fusion evaluation results, and various consistency indicators, the main sources of uncertainty for the current measuring point are identified. These main sources of uncertainty include one or more of the following: excessively wide confidence range of the current benchmark results; inconsistent trends among neighboring measuring points; uncertain interpretation of borehole fracture orientation; uncertain interpretation of borehole-induced tensile fractures; uncertain core pancake records; unclear interpretation of borehole wall imaging or borehole television data; uncertain rock elastic parameters; uncertain borehole attitude or spatial location of the measuring point; uncertain principal stress direction; uncertain principal stress magnitude; unstable principal stress ranking; and significant contradictions among auxiliary information.

[0083] When identifying major sources of uncertainty, if the current benchmark result of the measuring point has a wide confidence range, the source of uncertainty is marked as the current benchmark result of the measuring point being unstable; if the depth change trend formed by adjacent measuring points above and below the same borehole differs significantly from the current measuring point result, the source of uncertainty is marked as the adjacent depth trend being inconsistent; if the borehole fracture azimuth, induced tension fracture azimuth, and the current measuring point benchmark principal stress direction differ significantly, the source of uncertainty is marked as the direction-related auxiliary information being contradictory; if the core piecing characteristics are inconsistent with the current measuring point principal stress difference or high geostress judgment, the source of uncertainty is marked as the core piecing record being uncertain; if the fusion evaluation result changes significantly after adding or removing a certain auxiliary information, the auxiliary information is marked as sensitive information that has a significant impact on the result.

[0084] In step S9, based on the reliability level obtained in step S7 and the main sources of uncertainty identified in step S8, active measurement point optimization suggestion information is generated. This active measurement point optimization suggestion information is used to recommend one or more of the following options: re-measurement of the current measurement point, re-measurement of nearby depth-densified core measurement points, re-measurement of nearby abnormal measurement points, supplementary drilling in different azimuths, borehole wall imaging verification, borehole television verification, core pancake record verification, supplementary measurement of rock elastic parameters, and independent geostress testing verification.

[0085] When the reliability level of the current measuring point is higher than the threshold (i.e., the reliability level is high), and the confidence range of the principal stress magnitude and direction meets the engineering requirements, the output of the current measuring point result can be used as a prompt for subsequent engineering analysis. When the reliability level of the current measuring point is low, or the confidence range of the principal stress is wide, or there are obvious contradictions in the auxiliary information, the output of corresponding suggestions for retesting, densifying measuring points, or supplementing tests will be provided.

[0086] In this embodiment, multiple candidate schemes can be set, such as retesting the current measuring point, densifying measuring points at nearby depths, supplementing boreholes in different orientations, verifying borehole wall imaging, verifying borehole television, verifying core pancake records, and supplementing rock elastic parameters. When the reliability level is lower than the threshold, i.e., the reliability level is low, the candidate scheme is determined based on the uncertainty source information.

[0087] For example, when the main source of uncertainty is that the current benchmark result of the measuring point has an excessively wide range of credibility, it is recommended to remeasure the current measuring point or to densify the core measuring points at a depth adjacent to the current measuring point; when the main source of uncertainty is that the trend of adjacent depths is inconsistent, it is recommended to densify the measuring points between adjacent measuring points or to remeasure abnormally close measuring points; when the main source of uncertainty is that the direction of the principal stress is uncertain, it is recommended to conduct borehole wall imaging verification, borehole television verification, or to supplement boreholes in different orientations; when the main source of uncertainty is that the magnitude of the principal stress is uncertain, it is recommended to supplement rock elastic parameter testing, densify the measuring points at adjacent depths, or use independent geostress testing methods for verification; when the main source of uncertainty is that there are contradictions in the borehole fracture, induced tension fracture, or core pancake records, it is recommended to verify the borehole fracture orientation, induced tension fracture orientation, core pancake records, or relevant field logging data.

[0088] In this embodiment, when multiple candidate solutions are determined, the candidate solutions can be prioritized. Let the first... The expected improvement of the width of the confidence interval for the principal stress magnitude by the candidate solutions is: The expected improvement in the confidence range of the principal stress direction is The expected improvement in the degree of contradiction of multi-source information is The construction cost is Feasibility of implementation is Then the first The priority evaluation of each candidate solution can be expressed as:

[0089] In the formula, to These are the weighting coefficients. The larger the value, the better the overall effect of the candidate scheme in reducing the uncertainty of the current measurement points, alleviating the contradiction of multi-source information, and improving the feasibility of the project. According to The algorithm ranks the various methods, including re-measurement of the current measuring point, densification of measuring points at nearby depths, supplementary drilling in different orientations, borehole wall imaging verification, borehole television verification, core pancake recording verification, and supplementary measurement of rock elastic parameters. It then outputs the candidate method with the highest priority as the preferred active measuring point optimization method and generates active measuring point optimization suggestions.

[0090] Using an underground engineering project as an example, this paper describes the optimization method for active measuring points in geostress testing using the core-removal method that integrates multi-source uncertain constraints.

[0091] This embodiment uses a core stress relief measuring point in a test section of an underground engineering project as an example to further illustrate the specific implementation process of the present invention. Multiple core stress measuring points are arranged along the borehole depth direction in this test section. Measuring point P1 is selected as the current measuring point to be evaluated. Measuring points P0 and P2, located at adjacent depths above and below P1 within the same borehole, are selected as depth trend reference measuring points. Measuring point Q1 in a nearby borehole is selected as a spatial proximity reference measuring point. The overall processing flow of the core stress relief method for active measuring point optimization, which integrates multi-source uncertain constraints, is as follows: Figure 1 As shown.

[0092] First, acquire the core stress relief test data for the current measuring point P1 and establish a data archive for that point. This data archive includes the measuring point number, borehole number, measuring point depth, measuring point spatial location, borehole azimuth, borehole inclination, strain gauge installation angle, strain gauge arrangement parameters, rock elastic modulus, Poisson's ratio, borehole diameter, core size, test time, sampling frequency, instrument zero-point information, ambient temperature, and strain release curve. This data is used to calculate the geostress benchmark results for the current measuring point P1 and its reliability range. Figure 2 As shown.

[0093] Then, multi-source auxiliary information related to the current stress state at measuring point P1 is acquired, and an auxiliary information archive is established. This multi-source auxiliary information includes the stress results of adjacent measuring points P0 and P2 within the same borehole, the stress results of measuring point Q1 in a nearby borehole, the borehole fracture azimuth obtained from borehole wall imaging or borehole television interpretation, the borehole induced tension fracture azimuth, and core pancake records. For each type of auxiliary information, its information type, observed or interpreted value, data source, spatial location, applicable depth range, identification method, identification reliability, error range, and spatial relationship with the current measuring point P1 are recorded. Information with unclear sources, ambiguous applicable depth ranges, or questionable interpretation results is initially recorded as information awaiting verification.

[0094] Based on the core stress relief test data of the current measuring point P1, the benchmark result of the current measuring point and its confidence range are calculated. Specifically, according to the transformation relationship between the engineering coordinate system, the borehole coordinate system, and the strain gauge local coordinate system, combined with the borehole azimuth, borehole inclination, strain gauge installation angle, rock elastic modulus, and Poisson's ratio, the response relationship between the strain release at the current measuring point and the components of the three-dimensional geostress tensor is established. Let the observed strain vector at the current measuring point be... The strain-stress response matrix is The three-dimensional geostress tensor component vector is Then we have:

[0095] In the formula, This represents the observation error term. The three-dimensional geostress tensor component vector can be expressed as:

[0096] Without introducing multi-source auxiliary information such as P0, P2, Q1, borehole fracture azimuth, borehole-induced tensile fracture azimuth, and core pancake records, calculate the baseline geostress distribution at the current measuring point P1:

[0097] In the formula, This represents the baseline ground stress distribution at the current measuring point P1. To understand the constraint effect of the current core stress relief data on the geostress results, This serves as a constraint on the physical feasibility range of geostress. Based on this baseline distribution, the three-dimensional geostress components, principal stress magnitudes, principal stress directions, and corresponding confidence ranges of P1 are obtained. This baseline result is not the final evaluation result, but rather a reference for subsequent judgments regarding whether multi-source auxiliary information is consistent with the P1 result.

[0098] Subsequently, the multi-source auxiliary information was converted into auxiliary constraint information that could participate in consistency judgment and multi-source fusion evaluation. For adjacent measuring points P0, P2, and Q1, their geostress results were converted into reference information such as principal stress magnitude, principal stress direction, stress components, or principal stress difference. Among them, P0 and P2 are used to characterize the trend of geostress variation with depth within the same borehole, while Q1 is used to characterize the geostress state at adjacent spatial locations. For borehole fracture azimuth and borehole induced tension fracture azimuth, they were converted into reference information on the horizontal principal stress direction based on borehole wall fracture type, induced tension fracture morphology, and field interpretation rules. For core disc formation characteristics, they were converted into reference information on high geostress state or large principal stress difference level based on disc formation depth, disc formation frequency, disc thickness, and disc formation continuity.

[0099] like Figure 3 As shown, in this embodiment, P0 and P2 are located at adjacent depths above and below the current measuring point P1, mainly used to determine whether P1 conforms to the stress change trend formed by measuring points at adjacent depths; Q1 is located in a nearby borehole, mainly used to determine whether the stress state of P1 is consistent with that of the adjacent spatial location. The borehole fracture azimuth and the borehole-induced tensile fracture azimuth are used to assist in determining the direction of the horizontal principal stress, and the core pancake record is used to assist in determining the high stress state or the level of the principal stress difference.

[0100] For each type of auxiliary information, a consistency index is further calculated between it and the current measurement point P1 benchmark result. The consistency index includes directional consistency index, stress magnitude consistency index, depth variation trend consistency index, and fusion result impact index. For directional auxiliary information, the 180-degree equivalent directional difference between the given direction and the principal stress direction of the P1 benchmark is compared; for stress magnitude auxiliary information, the differences between the given principal stress magnitude, stress components, or principal stress difference and the P1 benchmark result are compared; for auxiliary information with a defined depth location, whether it conforms to the depth variation trend formed by P0 and P2 is compared; for the fusion result impact index, the degree of change in the P1 geostress result after adding or removing a certain auxiliary information is compared.

[0101] In this embodiment, if the principal stress directions and magnitudes formed by P0 and P2 change continuously with depth, and the benchmark result of P1 is basically consistent with this trend, it indicates that P1 has good consistency with adjacent depth measurement points in the same borehole. If the result of Q1 differs significantly from the trends formed by P0, P1, and P2, and Q1 is spatially far from P1 or located in different structural influence areas, the reliability of the auxiliary information of Q1 is reduced, or Q1 is marked as information to be verified. If the horizontal principal stress directions given by the borehole fracture azimuth and borehole-induced tensile fracture azimuth are close to the benchmark principal stress direction of P1, their reliability in direction determination is improved; if the difference between the two is large, they are recorded as contradictory auxiliary information of direction. If the core pancake record indicates a high geostress state, but neither the benchmark result of P1 nor the results of adjacent measurement points show a large principal stress difference, the core pancake record is marked as information to be verified.

[0102] Based on the aforementioned consistency indicators, the reliability of each auxiliary information is updated. Auxiliary information that is largely consistent with the P1 baseline result, the depth trends of P0 and P2, and other multi-source information maintains high reliability and retains its role in subsequent fusion evaluation. Auxiliary information with unclear sources, mismatched applicable depths, or significant contradictions with other information has its reliability reduced. Auxiliary information showing anomalies in multiple consistency indicators is marked as information awaiting review and is not directly used as a reliability constraint in the multi-source fusion evaluation.

[0103] like Figure 4 As shown, after completing the consistency judgment and reliability update of auxiliary information, the baseline results of the current measuring point P1 are used together with the multi-source auxiliary information that can participate in the fusion evaluation for the multi-source fusion evaluation of the geostress at the current measuring point. Let the first... The auxiliary constraint terms corresponding to each piece of auxiliary information are: The reliability of the updated auxiliary information is The multi-source fusion evaluation result of the current measurement point P1 can be expressed as:

[0104] In the formula, This represents the current stress relief data for the core sleeve at measuring point P1, along with the set of multi-source auxiliary information used in the fusion evaluation. The amount of auxiliary information participating in the integrated evaluation, Indicates the first The auxiliary information provides a constraint on the current geostress state. This indicates the reliability of the auxiliary information after consistency assessment. The higher the value, the stronger the role of this auxiliary information in the fusion evaluation; The lower the value, the weaker the role of the auxiliary information in the fusion evaluation. When a piece of auxiliary information is marked as information to be reviewed, it is not used as a reliable constraint in the fusion evaluation, or it is only output as information to illustrate the results.

[0105] Based on the multi-source fusion evaluation results, the magnitudes and directions of the three-dimensional geostress components, maximum principal stress, intermediate principal stress, and minimum principal stress of P1 are calculated, and the confidence intervals for principal stress magnitudes, confidence ranges for principal stress directions, and uncertainty ranges for geostress tensor components are given. When the magnitudes of two or more principal stresses are close, the stability of the principal stress ranking is further assessed. The reliability of the P1 results is graded based on the confidence range of the P1 baseline results, the consistency index of multi-source auxiliary information, the reliability of the updated auxiliary information, the width of the confidence interval for principal stresses, and the dispersion of principal stress directions. Reliability grades include high reliability, relatively reliable, generally reliable, low reliability, and invalid.

[0106] Furthermore, identify the main sources of uncertainty at the current measuring point P1. If the reliability range of the P1 baseline result is relatively wide, mark the source of uncertainty as an unstable baseline result at the current measuring point; if the depth change trends formed by P0 and P2 differ significantly from the P1 result, mark it as an inconsistency in the adjacent depth trends; if the borehole fracture azimuth or borehole-induced tensile fracture azimuth differs significantly from the P1 baseline principal stress direction, mark it as contradictory directional auxiliary information; if the core pancake record is inconsistent with the P1 principal stress difference or high geostress judgment, mark it as an uncertain core pancake record; if the fusion evaluation result changes significantly after adding or removing a certain auxiliary information, mark that auxiliary information as sensitive information that has a significant impact on the result.

[0107] Finally, as Figure 5 As shown, based on the reliability level of P1 and the main sources of uncertainty, active measurement point optimization suggestions are generated. When the reliability level of P1 is high and the confidence range of the principal stress magnitude and direction meets the engineering requirements, the output of P1 results can be used as a prompt for subsequent engineering analysis. When the reliability level of P1 is low, or the confidence range of the principal stress is wide, or there are obvious contradictions in the multi-source auxiliary information, suggestions for retesting, densifying measurement points, or supplementing tests are output.

[0108] Specifically, when the main source of uncertainty is that the credibility range of the P1 benchmark result is too wide, it is recommended to retest P1 or to densify the core sampling points at a depth close to P1; when the main source of uncertainty is that the depth trends formed by P0 and P2 are inconsistent, it is recommended to densify the sampling points between P0 and P1 or between P1 and P2, or to retest sampling points near anomalies; when the main source of uncertainty is the uncertainty of the principal stress direction, it is recommended to conduct borehole wall imaging verification, borehole television verification, or supplement boreholes in different orientations; when the main source of uncertainty is the uncertainty of the principal stress magnitude, it is recommended to supplement rock elastic parameter testing, densify sampling points at a depth close to the target, or use independent geostress testing methods for verification; when the main source of uncertainty is the borehole fracture, induced tension fracture, or contradictions in the core pancake record, it is recommended to verify the borehole fracture orientation, induced tension fracture orientation, core pancake record, or relevant field logging data.

[0109] When ranking multiple candidate optimization schemes, the expected improvement in the width of the confidence interval of principal stress magnitude, the expected improvement in the confidence range of principal stress direction, the expected improvement in the degree of contradiction of multi-source information, construction cost, and implementation feasibility can be comprehensively considered. Schemes with more significant expected improvement effects, lower construction costs, and higher implementation feasibility have higher priority. Upon completion of this embodiment, the three-dimensional geostress components, principal stress magnitude and direction, principal stress confidence range, measurement point reliability level, main sources of uncertainty, reliability of each auxiliary information, and active measurement point optimization suggestions for P1 are output.

[0110] Compared with related core stress data processing techniques, the active measurement point optimization method for core stress testing in this embodiment, which integrates multi-source uncertain constraints, has the following advantages: 1. Able to determine whether multi-source information is consistent with each other: It not only uses the stress relief data of the core at the current measuring point, but also integrates multi-source information such as the results of adjacent measuring points, borehole fracture orientation, induced tension fracture orientation, core piecing characteristics and borehole wall imaging data. It identifies conflict relationships between different information by directional consistency, size consistency, depth trend consistency and the degree of influence of the results. 2. It can reduce the impact of erroneous auxiliary information on geostress results: For auxiliary information with unclear sources, mismatched applicable depths, or obvious conflicts with other information, this invention can reduce its reliability or temporarily not use it, avoiding the direct inclusion of erroneous auxiliary information as a fixed constraint in the geostress evaluation process.

[0111] 3. It can improve the reliability evaluation capability of individual measuring point geostress results: Based on the current benchmark inversion results of measuring points, combined with the consistency of multi-source auxiliary information and the stability of fusion results, it outputs the reliability level of measuring points, the confidence interval of principal stresses and the confidence domain of directions, so that the test results are no longer limited to a single deterministic geostress value.

[0112] 4. Able to identify the main sources of uncertainty in geostress test results: It can distinguish the different causes of uncertainty, such as current measuring point data, trends of adjacent measuring points, interpretation of borehole fractures, interpretation of induced tension fractures, core disc records, and instability of rock elastic parameters or principal stress directions, thus providing a basis for subsequent verification.

[0113] 5. Able to guide retesting and supplementary testing: Based on the reliability level of the measuring point, the type of multi-source information conflict, and the source of uncertainty, it automatically generates suggestions such as retesting the current measuring point, densifying measuring points at nearby depths, supplementing boreholes, verifying borehole wall imaging, verifying borehole television, verifying core pancake records, or supplementing rock mechanical parameters, thereby improving the pertinence of subsequent measuring point layout and supplementary testing.

[0114] 6. It can realize a closed loop of evaluation of geostress test results and active measurement point optimization: By combining geostress inversion results, consistency evaluation of multi-source information, reliability classification and ranking of supplementary measurement schemes, the core geostress test is transformed from a single-point result output into a reliability evaluation and active optimization process oriented towards engineering decision-making.

[0115] The active measurement point optimization method for core-removal method in geostress testing in this embodiment, which integrates multi-source uncertainty constraints, does not simply perform single-point inversion of the core strain data of the current measurement point. Instead, based on the obtained geostress baseline results of the current measurement point, it further introduces auxiliary information from multiple sources, such as geostress results from neighboring measurement points, borehole fracture azimuth, borehole induced tensile fracture azimuth, core disc formation characteristics, borehole wall imaging, or borehole television interpretation results. It determines whether different information is consistent with each other and dynamically updates the reliability of each auxiliary information according to the degree of consistency. Through the active measurement point optimization method for core-removal method in geostress testing in this embodiment, it can avoid the unreasonable influence of auxiliary information with unclear sources, mismatched applicable depths, or obvious conflicts with other information on the geostress results of the current measurement point. Based on the reliability level of the measurement point and the source of uncertainty, it provides active measurement point optimization suggestions such as retesting the current measurement point, densifying measurement points at nearby depths, supplementing boreholes at different azimuths, or auxiliary test verification. This provides field testers with optimization suggestions for the testing work of the current measurement point, which is beneficial for field testers to improve the testing work of the current measurement point.

[0116] A computer program can be written to execute the active measurement point optimization method for stress testing using the core removal method that integrates multi-source uncertain constraints as described in this embodiment. This computer program can be written into a computer device or storage medium. When the computer program is read and run, the active measurement point optimization method for stress testing using the core removal method that integrates multi-source uncertain constraints as described in this embodiment can be executed, thereby achieving the same technical effect as the active measurement point optimization method for stress testing using the core removal method that integrates multi-source uncertain constraints as described in this embodiment.

[0117] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," and "right" used in this disclosure are only relative to the relative positional relationships of the components of this disclosure in the accompanying drawings. The singular forms "a" and "the" used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. Moreover, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this embodiment specification is only for describing particular embodiments and is not intended to limit the invention. The term "and / or" as used in this embodiment includes any combination of one or more of the associated listed items.

[0118] It should be understood that although the terms first, second, third, etc., may be used to describe various elements in this disclosure, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, a first element may also be referred to as a second element without departing from the scope of this disclosure, and similarly, a second element may also be referred to as a first element. The use of any and all instances or exemplary language (“e.g.,” “such as,” etc.) provided in this embodiment is intended only to better illustrate embodiments of the invention and, unless otherwise required, does not impose a limitation on the scope of the invention.

[0119] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The method can be implemented using standard programming techniques—including a non-transitory computer-readable storage medium configured with a computer program, wherein such a storage medium causes the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

[0120] Furthermore, the procedures described in this embodiment can be performed in any suitable order unless otherwise indicated by this embodiment or clearly contradicted by the context. The procedures (or variations and / or combinations thereof) described in this embodiment can be executed under the control of one or more computer systems configured with executable instructions, and can be implemented by hardware or a combination thereof as code (e.g., executable instructions, one or more computer programs, or one or more applications) that commonly executes on one or more processors. A computer program includes multiple instructions executable by one or more processors.

[0121] Furthermore, the method can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of the invention can be implemented as machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention of this embodiment includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps above in conjunction with a microprocessor or other data processor. When programmed according to the methods and techniques of the invention, the invention also includes the computer itself.

[0122] A computer program can be applied to input data to perform the functions of this embodiment, thereby transforming the input data to generate output data stored in non-volatile memory. The output information can also be applied to one or more output devices, such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including specific visual depictions of physical and tangible objects generated on the display.

[0123] The above are merely preferred embodiments of the present invention. The present invention is not limited to the above-described embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention, as long as they achieve the technical effects of the present invention by the same means, should be included within the scope of protection of the present invention. Within the scope of protection of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. A method for optimizing active measuring points in geostress testing using a core-sleeve removal method that integrates multi-source uncertain constraints, characterized in that... The optimization method for active measuring points in geostress testing using the core-sleeve removal method, which integrates multi-source uncertainty constraints, includes: Obtain the stress relief test data of the core sleeve at the current measuring point; Multiple auxiliary information corresponding to the current measurement point is acquired from multiple sources; Based on the core stress relief test data, calculate the geostress benchmark result and its confidence range corresponding to the current measuring point; Convert the auxiliary information into auxiliary constraint terms; Calculate the consistency index between the auxiliary information and the geostress benchmark results; Based on the consistency index, the reliability of each piece of auxiliary information is updated to obtain the updated reliability. Based on the updated reliability, the multi-source fusion evaluation result of the geostress corresponding to the current measuring point is obtained; Based on the geostress benchmark results, the consistency index, and the geostress multi-source fusion evaluation results, identify the uncertainty sources corresponding to the current measuring point; The reliability level is determined based on the multi-source geostress fusion evaluation results, and active measurement point optimization suggestions are generated based on the reliability level and the uncertainty source information.

2. The method for optimizing active measurement points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 1, is characterized in that... The calculation of the geostress benchmark result and its confidence range corresponding to the current measuring point based on the core stress relief test data includes: Based on the stress relief test data of the core sleeve, determine the strain-stress response matrix. and the three-dimensional geostress tensor component vector ; According to the formula Determine the observed strain vector ;in, This is the observation error term; According to the strain-stress response matrix Three-dimensional geostress tensor component vector and the observed strain vector The constraint effect of the stress relief test data of the core sleeve on the in-situ stress results was determined. ; Based on the three-dimensional geostress tensor component vector Determine the a priori range constraints of the ground stress foundation. ; According to the formula Determine the reference ground stress distribution corresponding to the current measuring point. ; According to the reference geostress distribution The three-dimensional geostress components, principal stress magnitudes, principal stress directions, and corresponding confidence ranges corresponding to the current measuring point are calculated; wherein, the three-dimensional geostress components, the principal stress magnitudes, and the principal stress directions constitute the geostress reference result.

3. The method for optimizing active measurement points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 1, is characterized in that... The step of converting the auxiliary information into auxiliary constraint terms includes: For any of the aforementioned auxiliary information, the information is classified according to the geostress characteristics it reflects, and the corresponding classification category is determined. The classification categories include direction category, stress magnitude category, depth trend category, and result impact category. For the The aforementioned auxiliary information, according to the formula Determine the first The auxiliary constraint item corresponding to the auxiliary information. Among them, when the first The aforementioned auxiliary information belongs to the direction category. Indicates the first The difference in principal stress direction corresponding to the auxiliary information; when the first The aforementioned auxiliary information belongs to the stress magnitude category. Indicates the first The differences in principal stress magnitude, stress components, or principal stress difference corresponding to the auxiliary information; when the first... The aforementioned auxiliary information belongs to the deep trend category. This indicates the difference between the geostress benchmark result corresponding to the current measuring point and the depth variation trend of adjacent measuring points; No. The error scale corresponding to each of the aforementioned auxiliary information.

4. The method for optimizing active measurement points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 3, is characterized in that... The consistency index between the auxiliary information and the geostress benchmark results includes: When the The aforementioned auxiliary information belongs to the direction category, according to the formula... Determine the equivalent directional difference ;in, For the first The direction provided by the aforementioned auxiliary information. The representative value of the principal stress direction obtained by inverting the geostress benchmark results; according to the formula Determine the first The directional consistency index corresponding to the auxiliary information. ;in, The uncertainty scale for the principal stress direction obtained by inverting the aforementioned geostress benchmark results is given by [the relevant parameter]. For the first The interpretation error scale of the aforementioned auxiliary information; When the The aforementioned auxiliary information belongs to the stress magnitude category, according to the formula... Determine the first Stress magnitude consistency index corresponding to the auxiliary information. ;in, This represents the stress magnitude, stress components, or principal stress difference representative value corresponding to the aforementioned geostress benchmark results. For the first The corresponding value given by the aforementioned auxiliary information. This serves as the uncertainty scale for the corresponding stress quantity in the geostress benchmark results. For the first The error scale of the auxiliary information; When the The aforementioned auxiliary information belongs to the deep trend category, according to the formula... Determine the first Consistency index of depth change trend corresponding to the auxiliary information ;in, For the first The depth at which the aforementioned auxiliary information is located. For the current measurement point, the adjacent reliable measurement points are at depth The trend forecast value given here, For the first The corresponding value given by the aforementioned auxiliary information. The trend prediction value The uncertainty scale For the first The error scale of the auxiliary information; When the The aforementioned auxiliary information belongs to the category of result impact, according to the formula. Determine the first The fusion result impact index corresponding to the auxiliary information mentioned above ;in, Indicates not to include the aforementioned first... The representative value of the geostress result obtained when using auxiliary information. Indicates the addition of the first The representative value of the geostress result obtained after considering auxiliary information. As a reference scale for the corresponding changes in results Using the aforementioned directional consistency index The stress magnitude consistency index The consistency index of the depth change trend And the fusion result impact index The set of consistency indicators .

5. The method for optimizing active measuring points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 4, is characterized in that... The step of updating the reliability of each piece of auxiliary information based on the consistency index to obtain the updated reliability includes: For the first The auxiliary information sets the initial reliability. ; Set the directional consistency index Corresponding weights The stress magnitude consistency index Corresponding weights The consistency index of the depth change trend Corresponding weights And the fusion result impact index Corresponding weights ; According to the formula Determine the first The degree of overall contradiction corresponding to the aforementioned auxiliary information ; According to the formula Determine the first The update reliability corresponding to each of the auxiliary information .

6. The method for optimizing active measurement points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 5, is characterized in that... The step of updating the reliability of each piece of auxiliary information based on the consistency index to obtain the updated reliability further includes: Set a preset reliability threshold. ; when At that time, determine the first The aforementioned auxiliary information contributes to the multi-source fusion evaluation results of geostress. Evaluation process; when At that time, determine the first The aforementioned auxiliary information is to be verified and is not included in the evaluation process of the multi-source geostress fusion evaluation results.

7. The method for optimizing active measurement points for geostress testing using the core-removal method based on multi-source uncertain constraints as described in claim 5 or 6, characterized in that, The process of obtaining the multi-source fusion evaluation result of the geostress corresponding to the current measuring point based on the updated reliability includes: According to the formula Determine the multi-source fusion evaluation results of the geostress. ;in, The constraint effect of the stress relief test data on the geostress results is explained. For the a priori range constraints of the ground stress foundation, For the first The auxiliary constraint terms corresponding to each of the aforementioned auxiliary information. For the first The update reliability corresponding to each of the aforementioned auxiliary information. The number of auxiliary information items involved in the judgment.

8. The method for optimizing active measuring points for geostress testing using the core-sleeve removal method based on multi-source uncertain constraints as described in claim 7, is characterized in that... The step of generating active measurement point optimization suggestion information based on the reliability level and the uncertainty source information includes: When the reliability level is lower than the threshold, candidate solutions are determined based on the uncertainty source information; the candidate solutions include one or more of the following: retesting the current measuring point, densifying measuring points at nearby depths, supplementing boreholes in different orientations, borehole wall imaging verification, borehole television verification, core pancake recording verification, and supplementary measurement of rock elastic parameters. When there are multiple candidate solutions, prioritize each candidate solution. Based on the candidate scheme with the highest priority, the active measurement point optimization suggestion information is generated.

9. A computer device, characterized in that, It includes a memory and a processor, wherein the memory is used to store at least one program, and the processor is used to load at least one program to execute the active measuring point optimization method for core release method for geostress testing according to any one of claims 1-8.

10. A computer-readable storage medium storing a processor-executable program, characterized in that, The processor-executable program, when executed by the processor, is used to perform the active measurement point optimization method for stress testing using the core-removal method that integrates multi-source uncertain constraints as described in any one of claims 1-8.

Images