A method for evaluating lateral anti-sliding stability of dam body during construction period

Abstract

The application provides an evaluation method for lateral anti-sliding stability of a dam during a construction period, and relates to the technical fields of hydraulic engineering and geotechnical mechanics, and the method comprises the following steps: establishing a dam foundation structure model based on dam foundation geological survey data; identifying possible sliding modes of the dam based on the dam foundation structure model; calculating shear strength parameters of a sliding surface; calculating a dam resistance action ratio by using a partial coefficient method, and calculating a dam section safety coefficient by using a single safety coefficient method, so as to verify the lateral stability of the dam during the construction period. The application realizes quantitative analysis of the anti-sliding stability of the dam during the construction period by establishing the dam foundation structure model and combining the shear strength parameters of different sliding modes, avoids the problems of inaccurate identification of the sliding mode and unreasonable calculation parameters in the traditional method, and improves the evaluation precision of the anti-sliding stability of the dam during the construction period and the engineering safety.

Description

Technical Field

[0001] The present application relates to the technical fields of water conservancy engineering and rock and soil mechanics, and in particular to a method for evaluating the lateral anti-sliding stability of a dam during construction. Background Art

[0002] During the construction period, the dam body may experience lateral sliding problems due to factors such as bedrock structural characteristics, construction loads, rainfall, and groundwater seepage, affecting construction safety.

[0003] Most existing stability assessment methods rely on static calculations, which do not fully consider the impact of material parameter changes, bedrock structural characteristics and sliding modes during construction, resulting in insufficient accuracy in stability assessment. Summary of the Invention

[0004] The present application aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, the first purpose of this application is to propose a method for evaluating the lateral anti-sliding stability of a dam during construction.

[0006] The second object of the present application is to provide a device for evaluating the lateral anti-sliding stability of a dam during construction.

[0007] The third objective of this application is to provide an electronic device.

[0008] The fourth object of this application is to provide a computer-readable storage medium.

[0009] A fifth object of this application is to provide a computer program product.

[0010] To achieve the above objectives, the first embodiment of the present application proposes a method for evaluating the lateral anti-sliding stability of a dam during construction, comprising:

[0011] Based on the geological survey data of the dam foundation, the dam foundation layer structure, layer joint development and related geomechanical parameters are obtained, and a dam foundation structure model is established;

[0012] Based on the dam foundation structure model, possible sliding modes of the dam body are identified, including a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently sloping left bank as the bottom sliding surface and a steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface;

[0013] For each sliding mode, determining the shear strength parameters of the corresponding sliding surface, wherein the shear strength parameters include friction coefficient and cohesion;

[0014] For each sliding mode, based on the shear strength parameters of each sliding mode, the partial coefficient method is used to calculate the dam body resistance ratio and the single safety factor method is used to calculate the dam section safety factor, and the dam body stability is verified.

[0015] Optionally, obtaining the dam foundation layer structure, layer joint development and related geomechanical parameters based on the dam foundation geological survey data, and establishing a dam foundation structure model includes:

[0016] Obtain the lithology, thickness, interlayer contact relationship and weathering characteristics of the dam base strata and establish a dam base stratum distribution model;

[0017] Identify dam foundation joints, fissures, and faults, obtain their spatial distribution characteristics, inclination, dip, connectivity, and filling properties, and establish a joint and fissure model;

[0018] Conduct geotechnical mechanics tests to measure the shear strength, elastic modulus, and permeability of the dam foundation rock and soil, and establish a dam foundation mechanics model based on the geological conditions of the dam foundation;

[0019] Based on the dam foundation stratum distribution model, the joint and fissure model and the dam foundation mechanical model, a dam foundation structural model is constructed for use in sliding mode identification and stability calculation.

[0020] Optionally, based on the dam foundation structure model, possible sliding modes of the dam body are identified, wherein the sliding modes include a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently inclined left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface, including:

[0021] Based on the dam foundation stratum distribution model, the inclination, weathering degree and interlayer contact relationship of the dam foundation rock layer are analyzed to determine the area where the foundation surface may serve as the sliding surface. The shear strength parameters of the foundation surface are calculated in combination with the dam foundation mechanical model to identify the lateral sliding mode along the foundation surface toward the riverbed.

[0022] Based on the joint and fissure model, the spatial distribution characteristics, shear strength, connectivity and groundwater influence of the gently dipping layer joint surface are analyzed to determine that it is the bottom sliding surface. The spatial distribution and cutting effect of the steeply dipping cracks nearly parallel to the river direction are analyzed. Combined with the dam foundation mechanics model, the restraint force on the sliding block is calculated and it is determined to be the trailing edge cutting surface, thereby identifying the lateral sliding mode with the layer joint surface as the bottom sliding surface and the steeply dipping cracks as the trailing edge cutting surface.

[0023] Optionally, for each sliding mode, determining the shear strength parameters of the corresponding sliding surface, wherein the shear strength parameters include friction coefficient and cohesion, includes:

[0024] Based on the dam foundation rock and soil mechanics test data, the shear strength parameters of the rock / rock, rock / concrete and concrete / concrete contact surfaces are determined, and a shear strength parameter database is established;

[0025] For the lateral sliding mode along the foundation surface toward the riverbed, the shear strength parameters of the contact surface between the dam foundation and the concrete are selected to calculate the friction coefficient and cohesion of the foundation surface.

[0026] For the lateral sliding mode with the gently dipping bedding joint surface on the left bank as the bottom sliding surface and the steeply dipping cracks nearly parallel to the river direction as the trailing edge cutting surface, the friction coefficient and cohesion of the joint surface were calculated based on the filling conditions of the joints and cracks, shear test data and connectivity.

[0027] Optionally, the calculation of the dam body resistance action ratio using a partial coefficient method and the dam section safety factor using a single safety factor method based on the shear strength parameters of each sliding mode, and verification of the dam body stability, includes:

[0028] Calculating the anti-sliding resistance and sliding force in each sliding mode based on the shear strength parameters of the sliding modes;

[0029] For each sliding mode, the partial coefficient method is used to calculate the dam body resistance action ratio, and the calculation results are compared with the safety standards to verify the lateral stability of the dam section during the construction period. The single safety factor method is used to calculate the dam section safety factor, and the calculation results are compared with the safety standards to evaluate the anti-sliding stability of the dam body during the construction period;

[0030] Comparing the calculation results of the two methods, if the resistance action ratio and safety factor both meet the design requirements, the lateral anti-sliding stability of the dam body during the construction period meets the requirements; otherwise, the dam foundation treatment measures need to be adjusted or the construction plan needs to be optimized.

[0031] To achieve the above-mentioned purpose, the second embodiment of the present application proposes a device for evaluating the lateral anti-sliding stability of a dam during construction, comprising:

[0032] The construction module is used to obtain the dam foundation layer structure, layer joint development and related geomechanical parameters based on the dam foundation geological survey data, and to establish a dam foundation structure model;

[0033] an identification module for identifying possible sliding modes of the dam body based on the dam foundation structure model, wherein the sliding modes include a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently inclined left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface;

[0034] A first calculation module is used to determine the shear strength parameters of the corresponding sliding surface for each sliding mode, wherein the shear strength parameters include friction coefficient and cohesion;

[0035] The second calculation module is used to calculate the dam body resistance ratio using the partial coefficient method and the dam section safety factor using the single safety factor method for each sliding mode, and to verify the dam body stability.

[0036] To achieve the above-mentioned purpose, a third embodiment of the present application provides an electronic device, comprising: a processor, and a memory communicatively connected to the processor;

[0037] The memory stores computer-executable instructions;

[0038] The processor executes the computer-executable instructions stored in the memory to implement the method as described in any one of the first aspects above.

[0039] To achieve the above-mentioned purpose, the fourth embodiment of the present application proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the method as described in any one of the above-mentioned first aspects.

[0040] To achieve the above-mentioned purpose, the fifth embodiment of the present application proposes a computer program product, including a computer program, which, when executed by a processor, implements the method as described in any one of the above-mentioned first aspects.

[0041] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects:

[0042] By establishing a dam foundation structure model and combining it with geological survey data, the sliding modes that may occur during the dam construction period can be accurately identified, thereby improving the accuracy of sliding mode identification. The anti-sliding stability of the dam body is calculated by combining the partial coefficient method and the single safety factor method, ensuring that the calculation results are more comprehensive and reliable, avoiding the deviations that may exist in a single method. Calculations based on shear strength parameters make the anti-sliding resistance assessment more consistent with the actual stress conditions of the dam body, avoiding the problem of calculation errors caused by unreasonable parameter selection in traditional methods. A scientific stability assessment standard is provided. By comparing the resistance action ratio and the safety factor, the potential sliding risk during the dam construction period can be discovered in a timely manner, and construction optimization can be guided to improve project safety.

[0043] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0045] Figure 1A schematic flow chart of a method for evaluating the lateral anti-sliding stability of a dam during construction provided by an embodiment of the present application;

[0046] Figure 2 This is a schematic diagram of the lateral sliding mode analysis during the construction period of the left 7# water inlet dam section provided in the embodiment of the present application;

[0047] Figure 3 Schematic diagram of the lateral sliding mode analysis during the construction period of the right bank slope dam section provided in the embodiment of the present application. DETAILED DESCRIPTION

[0048] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0049] To address the problem of insufficient accuracy in existing stability assessments, the present invention provides a method for assessing the lateral anti-sliding stability of a dam during construction. Figure 1 This is a flow chart of a method for evaluating the lateral anti-sliding stability of a dam during construction provided by an embodiment of the present application. Figure 1 As shown, the method includes the following steps:

[0050] Step 101: Based on the geological survey data of the dam foundation, the layer structure, layer joint development and related geomechanical parameters of the dam foundation are obtained, and a dam foundation structure model is established.

[0051] In this embodiment of the present application, step 101 provides a method for establishing a dam foundation structural model based on dam foundation geological survey data. This method aims to provide basic support for lateral anti-sliding stability assessment during dam construction through comprehensive geological data collection, analysis, and modeling. Establishing the dam foundation structural model is a key step in subsequent sliding mode identification and stability calculations, ensuring a comprehensive characterization of the physical, mechanical, and structural properties of the dam foundation strata. This step includes the following specific contents:

[0052] During the dam construction period, the stability of the foundation is crucial to the safety of the entire project.

[0053] Therefore, the present application first needs to conduct a detailed survey of the dam foundation geology to obtain the stratification characteristics, rock-soil composition, development of structural planes, and related geomechanical parameters of the dam foundation. These data can be obtained through various technical means such as drilling, geophysical exploration, remote sensing image analysis, field geological investigation, and indoor rock-soil testing, and are used to analyze the spatial distribution characteristics and mechanical properties of the dam foundation rock-soil body. Different stratigraphic structures determine their bearing capacity and anti-sliding capacity, so accurately identifying the lithology, thickness, interlayer contact relationship, and weathering characteristics of the dam foundation strata is an important prerequisite for dam foundation structure modeling. Through lithology analysis of the dam foundation strata, the bedrock type, mineral composition, cementation degree, and mechanical strength can be determined, and the anti-sliding capacity and stability of different rock layers can be further judged. At the same time, the determination of the thickness of the dam foundation strata helps to identify the key bearing layer, soft interlayer, and weak parts that may affect the stability of the dam foundation. For areas with thickness changes or uneven deposition, further geological modeling is needed to accurately describe the interlayer change trend. In addition, the analysis of the interlayer contact relationship helps to identify whether there are soft interlayers, lithology changes, and stress concentration phenomena in the interlayer bonding surface, and to evaluate their influence on the sliding mode. In the process of long-term stress on the dam body, weathering may cause changes in rock mechanical properties, so the evaluation of weathering depth is crucial, especially for areas with deep weathering, the mechanical parameters of the weathering zone need to be determined to judge its potential impact on the stability of the dam foundation.

[0054] After identifying the basic characteristics of the dam foundation strata, the embodiments of the present application also need to identify the geological discontinuities within the dam foundation that may affect stability, such as joints, fractures, and faults, and establish a joint and fracture model based on this. The joint system of the dam foundation is one of the key factors affecting the anti-sliding capacity of the dam foundation, so the spatial distribution characteristics of the joints need to be analyzed in detail, including the inclination, tendency, joint spacing, joint extension range, and penetration rate of the joint group. Through core observation and indoor testing, the filling properties of the joints can be evaluated to determine whether there are soft fillings such as argillaceous fillings or secondary mineral precipitation, and combined with shear test data, the shear strength can be calculated. The classification of the fracture system is also very important, and it is necessary to distinguish between tensile fractures, shear fractures, and through fractures, and analyze their influence on the overall stability of the dam body. For dam foundations with faults, the size of the fault, the width of the fractured zone, and the degree of rock mass fracture need to be determined to judge whether the fault can become part of the potential sliding surface. Through the establishment of the joint and fracture model, the geological structure within the dam foundation can be more intuitively displayed, and data support can be provided for subsequent sliding mode identification and anti-sliding stability calculation.

[0055] In addition to geological structure modeling, further geotechnical testing is required to determine the key mechanical parameters of the dam foundation rock and soil. Parameters such as the shear strength, elastic modulus, and permeability of the dam foundation directly determine the stability of the dam under different operating conditions. Therefore, these key parameters can be obtained through indoor geotechnical testing and in-situ field testing. Shear strength parameters are primarily used to assess the dam foundation's ability to resist sliding, elastic modulus is used to analyze the deformation characteristics of the dam foundation rock and soil, and permeability parameters help assess the impact of groundwater on dam foundation stability. Groundwater seepage can weaken the shear strength of the dam foundation and even induce landslides or seepage failure. Therefore, the impact of groundwater must be fully considered during dam foundation structural modeling, and a detailed analysis of the groundwater's occurrence, flow path, and seepage pressure must be conducted. Based on the test data, a dam foundation mechanical model can be established to quantitatively describe the stress state, deformation characteristics, and anti-sliding capacity of the dam foundation.

[0056] Based on the comprehensive dam foundation layer distribution model, joint and fissure model, and dam foundation mechanical model, the embodiment of the present application finally establishes a complete dam foundation structural model. This model can not only accurately describe the geometric shape of the dam foundation, but also provide the location of the potential sliding surface and its shear strength characteristics. Through the dam foundation structural model, the stress state of the dam foundation at different construction stages can be analyzed more intuitively, and the anti-sliding stability calculation can be performed in combination with actual working conditions. At the same time, the model can also be used to analyze the impact of construction loads, groundwater effects, and long-term stress distribution on the stability of the dam foundation, and provide a scientific basis for the optimization of construction plans.

[0057] Through the embodiments of the present application, step 101 uses systematic data collection, detailed geological analysis, and comprehensive modeling methods to achieve a comprehensive characterization of the dam foundation's stratigraphic structure, geological discontinuities, and geotechnical properties. Compared to traditional methods, the technical solution provided by this application has significant advantages in terms of the accuracy of sliding mode identification, the reliability of dam foundation stability calculations, and the scientific nature of stability assessments during the construction period. By constructing a complete dam foundation structure model, it is possible to ensure that the anti-sliding stability assessment of the dam body during the construction period is more scientific and accurate, and can effectively improve the safety and long-term stability of the dam body project.

[0058] Step 102: Based on the dam foundation structure model, possible sliding modes of the dam body are identified. The sliding modes include a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently inclined left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface.

[0059] In an embodiment of the present application, step 102 provides a method for identifying possible sliding modes of the dam body based on the dam foundation structural model. This method aims to accurately determine the lateral sliding modes that may occur in the dam body during the construction period by analyzing the geometric, physical and mechanical properties of the dam foundation rock and soil. Accurate identification of sliding modes is a key step in the anti-sliding stability assessment and can effectively improve the safety of the dam body during the construction period. The core of this step is to systematically analyze the inclination angle, structural surface characteristics and mechanical properties of the dam foundation rock layer in combination with the dam foundation stratum distribution model, joint and fissure model and dam foundation mechanical model, and clarify the location of the potential sliding surface and the factors affecting stability.

[0060] During the construction of the dam body, different forms of lateral sliding may occur due to the inclination direction of the rock strata, the contact characteristics between layers, the development of joints and fissures, and the effects of construction loads. In the embodiment of this application, the focus is on identifying two main types of lateral sliding modes, namely the lateral sliding mode along the foundation surface toward the riverbed side and the lateral sliding mode with the joint surface of the gently inclined left bank as the bottom sliding surface and the steeply inclined fissures nearly parallel to the river direction as the rear edge cutting surface. Both modes may affect the stability of the dam foundation, so accurate identification and modeling analysis are required.

[0061] When identifying lateral sliding patterns along the foundation surface toward the riverbed, the first step is to analyze the inclination, weathering degree, and interlayer contact relationships of the dam foundation rock strata based on the dam foundation stratum distribution model to determine areas where the foundation surface may serve as a sliding surface. Generally, if the foundation surface is inclined toward the riverbed, the rock strata are severely weathered, and the interlayer bonding is poor, then this foundation surface is more likely to form a sliding surface. Furthermore, the shear strength parameters of the foundation surface must be calculated in conjunction with the dam foundation mechanics model to quantify the anti-sliding capacity of this area. If the calculation results indicate that the shear strength of the foundation surface is low and construction loads or groundwater pressure may further weaken its stability, then this area can be identified as potentially susceptible to lateral sliding along the foundation surface toward the riverbed.

[0062] When identifying a lateral sliding pattern with the gently dipping left bank joint surface as the bottom sliding surface and the steeply dipping fissure parallel to the river direction as the trailing edge cutting surface, the analysis is mainly based on the joint and fissure model. First, it is necessary to study the spatial distribution characteristics of the gently dipping layer joint surface, especially its inclination angle, shear strength and connectivity. If the joint surface is consistent with the strike of the dam foundation rock layer and the inclination angle is small, a larger sliding body may be formed. At the same time, the influence of groundwater needs to be considered. If groundwater infiltrates along the joint surface, it may reduce the effective stress on the joint surface, thereby increasing the possibility of sliding. Therefore, it is necessary to calculate the shear strength parameters of the joint surface in combination with the dam foundation mechanical model to evaluate its stability.

[0063] At the same time, it is also necessary to analyze the spatial distribution and cutting effect of steeply dipping cracks that are nearly parallel to the river direction. Steeply dipping cracks usually serve as the cutting surface of the trailing edge of the sliding block. If the crack connectivity is high, and the intersection of the joint surface and the crack forms a through sliding surface, lateral sliding may occur in this area. In order to quantitatively analyze the restraining force of steeply dipping cracks on the sliding block, it is necessary to calculate the shear strength parameters of the cutting surface in combination with the dam foundation mechanical model to determine its restraining ability against sliding. If the crack filling is relatively weak, or the crack extends along the shear direction of the dam foundation, the anti-slip ability of this area may be low, resulting in lateral sliding of the sliding body.

[0064] The method of the embodiment of this application can systematically identify lateral sliding patterns during dam construction, and combined with dam foundation structure modeling and mechanical analysis, accurately assess sliding risks. Compared to traditional methods, the sliding pattern identification method provided in this application has advantages in terms of comprehensive data acquisition, accuracy of calculation models, and applicability. This method can identify potential sliding risk areas before dam construction, providing a scientific basis for subsequent anti-sliding stability calculations and construction plan optimization, thereby effectively improving the stability and safety of the dam during construction.

[0065] Step 103 : for each sliding mode, determining the shear strength parameters of the corresponding sliding surface, where the shear strength parameters include friction coefficient and cohesion.

[0066] In this embodiment of the present application, step 103 provides a method for determining the shear strength parameters of the sliding surface for different sliding modes. This method aims to obtain the friction coefficient and cohesion of the sliding surface through experimental measurement and computational analysis to quantify the shear strength characteristics of the sliding surface and provide basic data for subsequent anti-sliding stability assessment. The accuracy of the shear strength parameters directly affects the reliability of the dam foundation anti-sliding stability calculation. Therefore, systematic testing and calculation methods are required to ensure that the selected parameters truly reflect the engineering characteristics of the dam foundation.

[0067] First, in order to fully understand the shear properties of the dam foundation, the embodiments of the present application are based on the dam foundation rock and soil mechanics test data to measure the shear strength parameters of the contact surfaces of different materials. The shear properties of the dam foundation rock and soil vary due to different contact surfaces. Therefore, it is necessary to measure the shear strength parameters of the rock / rock, rock / concrete and concrete / concrete contact surfaces respectively, and establish a shear strength parameter database. During the test, the shear strength of different contact surfaces under different normal stresses was measured through direct shear tests, triaxial shear tests, rock shear tests and interface direct shear tests. By fitting the experimental data, the friction coefficient and cohesion of different contact surfaces under different working conditions can be obtained, and a parameter database suitable for the calculation of the anti-sliding stability of the dam foundation can be further established. This database can not only provide standardized shear strength parameters, but also provide data support for subsequent construction optimization.

[0068] In an embodiment of the present application, for the lateral sliding mode along the foundation surface toward the riverbed side, it is necessary to calculate the friction coefficient and cohesion of the foundation surface. In this mode, the sliding surface is mainly the contact interface between the dam foundation rock and the concrete, so the shear strength parameter of the rock / concrete contact surface is selected as the shear characteristic index of the foundation surface. Since the foundation surface may have local weakening phenomena, such as weathering zones or microcracks formed during the construction process, it is necessary to correct the friction coefficient and cohesion to ensure that the calculated parameters can accurately reflect the actual anti-slip ability of the foundation surface. In addition, if there are construction walkways or other structural measures on the foundation surface, their surface roughness may affect the shear strength, so it is necessary to combine the on-site measurement data to reasonably adjust the shear parameters.

[0069] For a lateral sliding mode with a gently dipping left bank joint surface as the bottom sliding surface and a steeply dipping fissure parallel to the river direction as the trailing edge cutting surface, the shear strength of the sliding surface is primarily controlled by the characteristics of the joint surface. Therefore, it is necessary to calculate the friction coefficient and cohesion of the joint surface based on the filling conditions of the joint fissures, shear test data, and connectivity. First, the type and mechanical properties of the joint filling are analyzed. If the joint is filled with weak materials such as clay minerals or weathered residues, the shear strength of the joint will be significantly reduced. Therefore, it is necessary to reduce the friction coefficient and cohesion in the calculation. Second, combined with the shear test data, the variation pattern of the shear strength of the joint surface is analyzed. In combination with the dam foundation mechanical model, the shear strength of the joint surface under different normal stresses is calculated. For joint systems with a high connectivity, the permeability of the joint surface may lead to a decrease in the overall shear strength. Therefore, it is necessary to consider the influence of the connectivity and make appropriate adjustments in the calculation. Finally, when calculating the shear parameters of steeply inclined cracks, it is necessary to focus on analyzing the roughness, width, and filling characteristics of the cracks. If the crack width is large or the filling inside the crack is weak, the restraining force of the trailing edge cutting surface may be reduced, thereby affecting the stability of the overall sliding body.

[0070] The technical solution provided in the embodiments of this application accurately determines the shear strength parameters of the sliding surface under different sliding modes through a method that combines experimental measurement with computational analysis. Compared with traditional methods, this method has the advantages of comprehensive parameter acquisition, clear calculation logic, and strong applicability. It can ensure the accuracy of sliding mode identification and provide scientific and reliable data support for the anti-sliding stability assessment during the dam construction period. Through the embodiments of this application, the accuracy of the anti-sliding stability calculation of the dam foundation can be effectively improved, and key technical support can be provided for safety control during dam construction.

[0071] Step 104 : Based on the shear strength parameters of each sliding mode, the dam body resistance action ratio is calculated using the partial coefficient method and the dam section safety factor is calculated using the single safety factor method, and the dam body stability is verified.

[0072] In this embodiment of the present application, step 104 provides a method for calculating the anti-sliding stability of the dam body based on different sliding modes. This method quantitatively analyzes the lateral anti-sliding stability of the dam body during construction by combining the partial coefficient method and the single safety factor method. The assessment of anti-sliding stability is directly related to the safety of the dam body during the construction phase. Therefore, this method calculates the anti-sliding resistance and sliding force, combining different calculation methods for comparative analysis to ensure that the stability of the dam body during construction meets the design requirements.

[0073] Before calculating the dam's anti-sliding stability, it is necessary to first calculate the anti-sliding resistance and sliding force for each sliding mode based on the shear strength parameters of the sliding mode. The anti-sliding resistance is primarily determined by the shear strength of the sliding surface, which is affected by the friction coefficient, cohesion, and normal stress of the sliding surface. The sliding force, on the other hand, depends on the combined effects of the dam's deadweight, external loads, and groundwater penetration. During the dam construction period, changes in construction loads may lead to dynamic adjustments in the sliding force. Therefore, it is necessary to combine the dam foundation mechanical model to calculate the sliding force changes under different load conditions.

[0074] For the lateral sliding mode along the foundation surface toward the riverbed side and the lateral sliding mode with the layer joint surface on the gently inclined left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the rear edge cutting surface, this application uses the partial coefficient method to calculate the dam body's resistance action ratio, and compares the calculation results with the engineering safety standards to verify the lateral stability of the dam section during the construction period. The calculation method of the partial coefficient method takes into account the influence of different load combinations and can more accurately evaluate the anti-sliding stability of the dam body at different construction stages. By calculating the resistance action ratio, it can be determined whether the dam body has sufficient anti-sliding ability. If the resistance action ratio is higher than the engineering specification requirements, it means that the dam body can remain stable under the current working conditions; if the resistance action ratio is lower than the specification standard, additional reinforcement measures may be required to improve the stability of the dam foundation.

[0075] In addition, to further verify the lateral stability of the dam, the single safety factor method is also needed to calculate the safety factor of the dam section and compare the calculated results with safety standards to assess the anti-sliding stability of the dam during construction. The single safety factor method is a commonly used method for assessing dam foundation stability. This method determines the anti-sliding ability of the dam by calculating the ratio of the shear strength on the sliding surface to the sliding force. If the calculated safety factor is greater than the engineering standard requirements, it means that the dam has sufficient anti-sliding ability during the construction phase. If the safety factor is too low, it may be necessary to adjust the construction sequence, optimize the dam foundation treatment measures, or take additional reinforcement measures to improve the anti-sliding stability of the dam foundation.

[0076] After completing the calculations of the partial coefficient method and the single safety factor method, it is necessary to compare and analyze the calculation results of the two methods to ensure the accuracy of the calculation results. Under normal circumstances, the partial coefficient method can reflect the impact of load changes during the construction period on the stability of the dam body in more detail, while the single safety factor method can provide an overall stability assessment result. Therefore, in the embodiment of the present application, by comparing the calculation results of the two methods, if the resistance action ratio and the safety factor both meet the design requirements, it can be determined that the lateral anti-sliding stability of the dam body during the construction period meets the engineering safety standards, and the dam body can remain stable during the construction process. However, if the calculation results show that the resistance action ratio or the safety factor does not meet the design standards, it is necessary to take corresponding dam foundation treatment measures, such as improving the quality of the foundation surface treatment, increasing the structural stability of the dam body, optimizing the construction sequence, or taking other engineering measures to enhance the anti-sliding ability to ensure the stability of the dam body during the construction period.

[0077] The anti-sliding stability calculation method provided in the embodiment of the present application combines the partial coefficient method with the single safety factor method, which can more comprehensively evaluate the lateral stability of the dam during the construction period. Compared with traditional methods, this method can more accurately analyze the anti-sliding ability of the dam foundation under conditions of changing construction loads, and at the same time combine different calculation methods to compare the results, thereby improving the reliability of the calculation and engineering applicability. Through the embodiments of the present application, it can ensure that the anti-sliding stability assessment of the dam during the construction period is more scientific and accurate, and can effectively improve the safety and engineering quality of the dam construction process.

[0078] In order to illustrate the specific application of this application, two embodiments are given below for illustration.

[0079] Example 1: Lateral sliding stability assessment of the left bank intake dam section during construction.

[0080] In order to illustrate the specific application of this application, the following is combined with the construction of the left bank water intake dam section, such as Figure 2 As shown, the application of the embodiment of the present application in the lateral anti-sliding stability assessment during the dam construction period is introduced.

[0081] According to the construction schedule, the left bank intake dam section (Left 7# to Left 10#) needs to be poured first. Therefore, the left bank non-overflow dam section may face lateral sliding stability issues along the foundation surface towards the riverbed during construction. Geological survey results show that the layer joints in the left bank area are not obvious, so the sliding mode in this section is mainly lateral sliding along the foundation surface towards the riverbed.

[0082] 1. Sliding mode analysis.

[0083] Based on the dam foundation geological survey data and the dam foundation structural model, the sliding mode of the left bank water intake section was analyzed to determine its sliding path and controlling factors. In the embodiments of this application, the lateral sliding mode along the foundation surface is affected by the stratum structure, the shear strength of the foundation surface, and the construction load. Due to the presence of the construction road, the shear resistance parameters of the sliding surface need to be calculated in combination with the rock / concrete shear resistance parameters and the rock / rock shear resistance parameters.

[0084] 2. Calculation of shear strength parameters.

[0085] In order to ensure the accuracy of the anti-sliding stability calculation, the shear strength parameters of the sliding surface are calculated based on the geotechnical test data. Since the sliding mode of this section is sliding along the foundation surface, the shear strength comprehensive parameter of the bottom sliding surface is the friction coefficient =1.0, =1000kPa. Since the sideslip surface is affected by the road, only the cohesion effect is considered and its cohesion is set to =1000kPa.

[0086] 3. Anti-slip stability calculation.

[0087] The embodiment of the present application uses the partial coefficient method and the single safety factor method to calculate the lateral anti-sliding stability of the dam during the construction period, and compares the calculation results with the engineering safety standards.

[0088] (1) Calculation using the item coefficient method.

[0089] The partial coefficient method evaluates the dam's anti-sliding capacity by calculating the resistance action ratio. The calculation results are shown in Table 1.

[0090] Table 1

[0091]

[0092] The calculation results show that the resistance action ratio of the left 7# dam section during the construction period is 1.02, which meets the engineering safety standards and indicates that the dam section has sufficient anti-sliding stability during construction.

[0093] (2) Calculation using the single safety factor method.

[0094] The single safety factor method evaluates the overall stability of the dam by calculating the safety factor K′. The calculation results are shown in Table 2.

[0095] Table 2

[0096]

[0097] The calculation results show that the safety factor K′ of the left 7# dam section is 3.03, which is much higher than the requirements of engineering specifications, further verifying the anti-sliding stability of the dam section during the construction period.

[0098] Example 2: Right 7# dam section construction period lateral stability evaluation.

[0099] To further illustrate the specific application of the present application, the following is combined with the construction of the right 7# dam section, as shown in Figure 3 , the application of the embodiment of the present application in the lateral stability evaluation of the dam body during construction is introduced.

[0100] 1. Sliding mode analysis.

[0101] During construction, there may be two main lateral sliding modes for the right bank non-overflow dam section:

[0102] Mode 1: The layer joint surface of the gently inclined left bank (Group IV N35°W, NE ∠14°) as the bottom sliding surface, the nearly parallel river direction steeply inclined fissure (Group I NW50°, SW ∠75°) as the rear edge cutting surface, forming lateral sliding to the river bed side.

[0103] Mode 2: Lateral sliding along the foundation surface to the river bed side, which is mainly affected by construction load, shear strength of the foundation surface and groundwater.

[0104] Through the analysis of the dam foundation structure model, it is found that the geological conditions of the right 7# dam section are relatively complex, the joint fissure is relatively developed, and the shear resistance is weak, which is one of the most dangerous dam sections on the right bank. Therefore, this dam section is selected for key lateral stability calculation.

[0105] 2. Shear strength parameter calculation.

[0106] Based on the dam foundation rock and soil mechanics test data, the shear strength parameters of the sliding surface under different sliding modes are calculated to ensure the accuracy of the anti-sliding stability calculation.

[0107] For sliding mode 1 (layer joint surface + steeply inclined fissure mode), since the connectivity rate of Group V structure surface is 52%, the shear surface adopts the weakly weathered upper rock mass parameters, and considering the connectivity rate, the shear strength parameters of the sliding surface are set as: =0.79, =606kPa.

[0108] For sliding mode 2 (sliding along the foundation surface mode), due to the existence of the construction road, the sliding surface is a combination of rock and concrete, and the average value of rock / rock shear strength parameters and concrete / concrete shear strength parameters is taken as the shear strength parameters of the sliding surface: =1.15, =1350kPa.

[0109] 3. Anti-sliding stability calculation.

[0110] The embodiment of the present application uses the partial coefficient method and the single safety factor method to calculate the lateral anti-sliding stability of the right 7# dam section during the construction period, and compares the calculation results with the engineering safety standards.

[0111] (1) Calculation using the item coefficient method.

[0112] The partial coefficient method evaluates the dam's anti-sliding capacity by calculating the resistance action ratio. The calculation results are shown in Table 3.

[0113] Table 3

[0114]

[0115] The calculation results show that the resistance action ratio of the left 7# dam section during the construction period is 1.02, which meets the engineering safety standards and indicates that the dam section has sufficient anti-sliding stability during construction.

[0116] The calculation results show that:

[0117] Under mode 1, the resistance action ratio of the right 7# dam section is 1.91, which is greater than 1.0, indicating that the shear resistance of the sliding surface is strong and the stability is high;

[0118] Under mode 2, the resistance action ratio of the right 7# dam section is 1.14, which is close to the safety limit but still meets the engineering safety requirements.

[0119] (2) Calculation using the single safety factor method.

[0120] The single safety factor method evaluates the overall stability of the dam by calculating the safety factor K′. The calculation results are shown in Table 4.

[0121] Table 4

[0122]

[0123] The calculation results show that:

[0124] Under mode 1, the safety factor K′ of the right 7# dam section is 5.43, which is much higher than the design requirement, indicating that the anti-sliding stability of the dam section is relatively high under this mode;

[0125] Under mode 2, K′ of the right 7# dam section is 3.45, which is also much higher than the design standard, further verifying the lateral anti-sliding stability of the dam section during the construction period.

[0126] This example comprehensively analyzes the lateral sliding stability of the right 7# dam section during construction by establishing a dam foundation structural model, identifying sliding modes, calculating shear strength parameters, and employing the partial coefficient method and single safety factor method to assess anti-sliding stability. The calculation results demonstrate that this dam section remained stable during construction, meeting engineering safety requirements.

[0127] The technical solution of the embodiment of this application can effectively identify potential slip risks under different sliding modes during the dam construction period, and ensure that the dam foundation design meets engineering safety standards by accurately calculating shear strength parameters and stability indicators. At the same time, by combining the partial coefficient method and the single safety factor method, not only the calculation accuracy is improved, but also the reliability of the results is enhanced. This method can be widely used to assess the stability of different types of dam foundations and provide a scientific basis for optimization and adjustment during the construction process, thereby improving the safety and engineering quality of the dam during the construction period.

[0128] To implement the above embodiment, the present application also proposes a device for evaluating the lateral anti-sliding stability of a dam during construction. The device includes:

[0129] The construction module is used to obtain the dam foundation layer structure, layer joint development and related geomechanical parameters based on the dam foundation geological survey data, and to establish a dam foundation structure model;

[0130] The identification module is used to identify possible sliding modes of the dam body based on the dam foundation structure model. The sliding modes include lateral sliding mode along the foundation surface toward the riverbed and lateral sliding mode toward the riverbed with the bedding joint surface on the gently sloping left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface.

[0131] A first calculation module is used to determine the shear strength parameters of the corresponding sliding surface for each sliding mode, where the shear strength parameters include friction coefficient and cohesion;

[0132] The second calculation module is used to calculate the dam body resistance ratio using the partial coefficient method and the dam section safety factor using the single safety factor method for each sliding mode, and to verify the dam body stability.

[0133] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0134] In order to implement the above embodiments, the present application also proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided by the above embodiments.

[0135] In order to implement the above embodiments, the present application also proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided by the above embodiments.

[0136] In order to implement the above embodiments, the present application also proposes a computer program product, including a computer program, which implements the methods provided by the above embodiments when executed by a processor.

[0137] The collection, storage, use, processing, transmission, provision and disclosure of user personal information involved in this application are in compliance with relevant laws and regulations and do not violate public order and good morals.

[0138] It is important to note that personal information collected from users should be used for legitimate and reasonable purposes and should not be shared or sold beyond these legitimate uses. Furthermore, such collection / sharing should be conducted only after receiving the user's informed consent, including but not limited to notifying the user to read the user agreement / user notice and sign an agreement / authorization that includes the relevant user information before using the feature. Furthermore, any necessary steps must be taken to safeguard and secure access to such personal information and ensure that others with access to personal information comply with its privacy policy and procedures.

[0139] This application contemplates providing implementations that allow users to selectively block the use or access of personal information data. Specifically, this disclosure contemplates providing hardware and / or software to prevent or block access to such personal information data. Risks can be minimized by limiting data collection and deleting data once it is no longer needed. Furthermore, where applicable, such personal information can be de-identified to protect user privacy.

[0140] In the descriptions of the foregoing embodiments, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are mutually inconsistent.

[0141] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0142] Any processes or methods described in the flowcharts or otherwise described herein can be understood as representing modules, segments, or portions of code that include one or more executable instructions for implementing specific logical functions or steps, and the various embodiments of the application can include additional or fewer steps performing the same or equivalent functions as those shown or discussed, in different orders, including substantially simultaneous execution of the functions described with respect to particular steps, and the like.

[0143] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a list of executable instructions for implementing the logic function, and can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor- containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-readable medium can specifically include the following, which are non-exhaustive listings: electrical connections (electrical apparatus), portable computer disks (magnetic apparatus), random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash memory), optical fiber devices, and portable compact disk read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable medium upon which the program can be printed, as the program can be electronically captured, for example, via the optical scanning of the paper or other medium, followed by the electronic conversion of the optically scanned program into a form that can be edited, compiled, or interpreted or otherwise processed into an electronically usable form, and then stored in the computer memory.

[0144] It should be understood that portions of the application can be implemented in hardware, software, firmware, or combinations thereof. In the above embodiments, the various steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. As such, if implemented in hardware and in another embodiment, any of the following technologies, known in the art, or their combinations, can be used to implement the hardware: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0145] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0146] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0147] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

[0148] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this application can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of this application can be achieved. This is not limited herein.

[0149] The above specific embodiments do not constitute a limitation on the scope of protection of this application. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application shall be included within the scope of protection of this application.

Claims

1. A method for evaluating the lateral anti-sliding stability of a dam during construction, characterized in that: The following steps are involved: Based on the geological survey data of the dam foundation, the dam foundation layer structure, layer joint development and related geomechanical parameters are obtained, and a dam foundation structure model is established; Based on the dam foundation structure model, possible sliding modes of the dam body are identified, including a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently sloping left bank as the bottom sliding surface and a steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface; For each sliding mode, determining the shear strength parameters of the corresponding sliding surface, wherein the shear strength parameters include friction coefficient and cohesion; Based on the shear strength parameters of each sliding mode, the partial coefficient method is used to calculate the dam body resistance ratio and the single safety factor method is used to calculate the dam section safety factor, and the dam body stability is verified.

2. The method according to claim 1, characterized in that The dam foundation geological survey data is used to obtain the dam foundation layer structure, layer joint development and related geomechanical parameters, and establish a dam foundation structure model, including: Obtain the lithology, thickness, interlayer contact relationship and weathering characteristics of the dam base strata and establish a dam base stratum distribution model; Identify dam foundation joints, fissures, and faults, obtain their spatial distribution characteristics, inclination, dip, connectivity, and filling properties, and establish a joint and fissure model; Conduct geotechnical mechanics tests to measure the shear strength, elastic modulus, and permeability of the dam foundation rock and soil, and establish a dam foundation mechanics model based on the geological conditions of the dam foundation; Based on the dam foundation stratum distribution model, the joint and fissure model and the dam foundation mechanical model, a dam foundation structural model is constructed for use in sliding mode identification and stability calculation.

3. The method according to claim 2, characterized in that Based on the dam foundation structure model, possible sliding modes of the dam body are identified. The sliding modes include a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the gently inclined left bank joint surface as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface, including: Based on the dam foundation stratum distribution model, the inclination, weathering degree and interlayer contact relationship of the dam foundation rock layer are analyzed to determine the area where the foundation surface may serve as the sliding surface. The shear strength parameters of the foundation surface are calculated in combination with the dam foundation mechanical model to identify the lateral sliding mode along the foundation surface toward the riverbed. Based on the joint and fissure model, the spatial distribution characteristics, shear strength, connectivity and groundwater influence of the gently dipping layer joint surface are analyzed to determine that it is the bottom sliding surface. The spatial distribution and cutting effect of the steeply dipping cracks nearly parallel to the river direction are analyzed. Combined with the dam foundation mechanics model, the restraint force on the sliding block is calculated and it is determined to be the trailing edge cutting surface, thereby identifying the lateral sliding mode with the layer joint surface as the bottom sliding surface and the steeply dipping cracks as the trailing edge cutting surface.

4. The method according to claim 3, characterized in that For each sliding mode, the shear strength parameters of the corresponding sliding surface are determined, wherein the shear strength parameters include friction coefficient and cohesion, including: Based on the dam foundation rock and soil mechanics test data, the shear strength parameters of the rock / rock, rock / concrete and concrete / concrete contact surfaces are determined, and a shear strength parameter database is established; For the lateral sliding mode along the foundation surface toward the riverbed, the shear strength parameters of the contact surface between the dam foundation and the concrete are selected to calculate the friction coefficient and cohesion of the foundation surface. For the lateral sliding mode with the gently dipping bedding joint surface on the left bank as the bottom sliding surface and the steeply dipping cracks nearly parallel to the river direction as the trailing edge cutting surface, the friction coefficient and cohesion of the joint surface were calculated based on the filling conditions of the joints and cracks, shear test data and connectivity.

5. The method according to claim 4, characterized in that For each sliding mode, the partial coefficient method is used to calculate the dam body resistance ratio and the single safety factor method is used to calculate the dam section safety factor, and the dam body stability is verified, including: Calculating the anti-sliding resistance and sliding force in each sliding mode based on the shear strength parameters of the sliding modes; For each sliding mode, the partial coefficient method is used to calculate the dam body resistance action ratio, and the calculation results are compared with the safety standards to verify the lateral stability of the dam section during the construction period. The single safety factor method is used to calculate the dam section safety factor, and the calculation results are compared with the safety standards to evaluate the anti-sliding stability of the dam body during the construction period; Comparing the calculation results of the two methods, if the resistance action ratio and safety factor both meet the design requirements, the lateral anti-sliding stability of the dam body during the construction period meets the requirements; otherwise, the dam foundation treatment measures need to be adjusted or the construction plan needs to be optimized.

6. A device for evaluating the lateral anti-sliding stability of a dam during construction, characterized in that: include: The construction module is used to obtain the dam foundation layer structure, layer joint development and related geomechanical parameters based on the dam foundation geological survey data, and to establish a dam foundation structure model; an identification module for identifying possible sliding modes of the dam body based on the dam foundation structure model, wherein the sliding modes include a lateral sliding mode along the foundation surface toward the riverbed and a lateral sliding mode toward the riverbed with the bedding joint surface on the gently inclined left bank as the bottom sliding surface and the steeply inclined crack nearly parallel to the river direction as the trailing edge cutting surface; A first calculation module is used to determine the shear strength parameters of the corresponding sliding surface for each sliding mode, wherein the shear strength parameters include friction coefficient and cohesion; The second calculation module is used to calculate the dam body resistance ratio using the partial coefficient method and the dam section safety factor using the single safety factor method based on the shear strength parameters of each sliding mode, and to verify the dam body stability.

7. An electronic device, characterized in that: include: a processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 5 when executed by a processor.

9. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 5 when executed by a processor.

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