BIM and three-dimensional reconstruction-based yard earthwork calculation system and method

Abstract

This invention discloses a reservoir earthwork quantity calculation system and method based on BIM and 3D reconstruction, belonging to the field of construction management technology. It includes: a data acquisition module for acquiring 3D real-world cloud data and on-site geological logging data of the reservoir area at each construction stage; a digital twin module for constructing a design BIM model and a 3D geological model, and generating a material identity block mesh model with material attributes; a core quantity calculation engine module for dynamically calculating excavation volume conversion coefficients, allocating material destinations, performing time-dependent volume reduction calculations on material identity blocks allocated to the transfer slag yard, and performing volume chain conversions under process flow conditions; and a visualization application module for overlaying and displaying the material identity block mesh model and its dynamic volume information in a BIM 3D view. This invention aims to solve the problems of separation between geology and quantity calculation, rigid coefficients, and lack of material traceability in traditional methods.

Description

Technical Field

[0001] This invention relates to the field of construction management technology, and in particular to a system and method for calculating earthwork volume in reservoir areas based on BIM and 3D reconstruction. Background Technology

[0002] In the earthwork engineering of pumped storage power station reservoir areas, traditional quantity calculation methods have long suffered from the following problems: Geological engineers manually draw weathering boundaries and fault boundaries on two-dimensional drawings based on a small number of borehole cores for qualitative evaluation of rock mass quality, while quantity calculation personnel cut cross-sections from topographic maps and calculate the total volume of excavation and filling based on homogeneous geometry; the geological model is only responsible for qualitative analysis, and the quantity calculation model is only responsible for quantitative analysis, with no spatial or data flow linkage between the two; when excavation reveals the true geological conditions, the quantity calculation model cannot be updated synchronously, and waste is continuously included in the effective volume, resulting in a serious discrepancy between the book volume and the actual usable volume; Meanwhile, regardless of the integrity, weathering degree, and construction technology of the rock mass, the conversion from natural volume to loose volume and from loose volume to compacted volume all use the fixed coefficients in the quota manual. This completely masks the physical differences in looseness and compaction characteristics between strongly weathered and fractured rock mass and intact hard rock mass, resulting in the problem that 1 million cubic meters were excavated on paper, but only 800,000 cubic meters were effectively filled on the dam face. Furthermore, information such as the geological attributes of the source of the excavated material, the location of the stockpile, the stockpile time, and the degree of surface weathering relies entirely on paper ledgers and the memory of on-site personnel. During the backfilling, only the total volume of the slag heap can be measured, and it is impossible to determine how many cubic meters of qualified cushion material or transition material are left in the slag heap. This leads to qualified material being discarded and weathered material being mistakenly put on the dam, which not only wastes resources but also creates hidden dangers in the quality of dam filling. Therefore, there is an urgent need in this field for a system and method for calculating earthwork volume in reservoir areas based on BIM and 3D reconstruction to solve the above problems. Summary of the Invention

[0003] The present invention aims to realize dynamic volume calculation of the entire process from excavation to filling, and solve the problems of separation between geology and volume calculation, rigid coefficients and lack of material traceability in traditional methods.

[0004] To achieve the above objectives, on the one hand, the present invention provides a reservoir area earthwork quantity calculation system based on BIM and 3D reconstruction, comprising: The data acquisition module is used to acquire three-dimensional real-world cloud data of the reservoir area and on-site geological logging data at each stage of construction. The digital twin module, connected to the data acquisition module, is used to construct the design BIM model and, using the three-dimensional real-world point cloud data and geological logging data, construct and update the three-dimensional geological model. Based on the design BIM model and the updated three-dimensional geological model, a material identity block mesh model with material attributes is generated. The core volume calculation engine module, connected to the digital twin module, is used to dynamically calculate the excavation volume conversion coefficient and allocate material destinations based on the material attributes in the material identity block grid model. It performs time-dependent volume reduction calculations based on three-dimensional reconstruction and registration for the material identity blocks allocated to the transfer slag yard, and performs volume chain conversion under the process flow state based on the material destination and time-dependent reduction results, and outputs dynamic volume information. The visualization application module, connected to the core quantity calculation engine module, is used to overlay and display the material identity block grid model and its dynamic volume information in the BIM 3D view.

[0005] On the other hand, this invention provides a method for calculating earthwork volume in a reservoir area based on BIM and 3D reconstruction, comprising the following steps: Step S1: Periodically collect three-dimensional real-time cloud data of the excavation face, slag yard and filling face of the reservoir area to obtain geological logging and wave velocity test data of the rock mass exposed by excavation; Step S2: Construct a design BIM model including the excavation area, filling area and slag yard; generate an initial three-dimensional geological model based on the initial borehole data; and update the geological interface in the three-dimensional geological model using the three-dimensional real-world point cloud data and geological logging data of each period. Step S3: Extract the planned excavation body corresponding to the current construction cycle from the design BIM model, perform spatial Boolean operation with the updated three-dimensional geological model, and perform three-dimensional meshing on the operation result to generate material identity blocks with unique identifiers. Each material identity block automatically inherits lithology and calculates the rock mass integrity coefficient and fault mudification index. Step S4: Calculate the dynamic loosening coefficient based on the rock mass integrity coefficient and excavation process parameters of the material identity block, convert the natural volume into loose volume, and allocate the material identity block to the direct dam area or intermediate slag yard in the design BIM model according to the fault mudification index and preset destination rules. Step S5: For material identification blocks destined for the transfer slag yard, write their initial loose volume, characteristic particle size, fault mudification index and entry timestamp into the database, and dynamically update the pile morphology and characteristic particle size through registration and segmentation of multi-phase slag yard three-dimensional real-world point cloud. Step S6: Periodically call the time-deduction model to calculate the effective usable loose volume of each material identity block in the slag yard after the storage time, and summarize the total amount of each type of qualified material; when the back mining is carried out, match the material identity blocks according to the dam filling material requirements, and convert them into effective compacted volume in combination with the rolling compaction coefficient. Step S7: Display the volume, quality, and destination information of the material identification blocks on the visualization interface of the BIM model design.

[0006] Compared with existing designs, the present invention has the following advantages: This invention dynamically updates the geological interface through 3D real-scene reconstruction and automatically assigns the updated geological attributes to material identity blocks, so that the quantity calculation model is updated synchronously with the construction and exposure, fundamentally eliminating the phenomenon of separation between quality and quantity.

[0007] This invention directly links the loosening coefficient with the rock mass integrity coefficient and the construction process energy factor, ensuring that the book volume always matches the physical reality and reducing material deficits.

[0008] This invention binds a unique identifier to each material identification block, records its geological attributes, stockpiling time, and characteristic particle size, and uses an aging reduction model to dynamically calculate the effective usable volume of qualified material in the slag yard, providing a basis for mining decisions and improving the utilization rate of qualified material. Attached Figure Description

[0009] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same parts.

[0010] Figure 1 This is a schematic diagram of the earthwork calculation system for the reservoir area provided in this embodiment; Figure 2 This is a flowchart illustrating the method for calculating earthwork volume in the reservoir area provided in this embodiment. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0012] Example 1: This example applies to the earthwork excavation and filling scenario of a pumped storage power station reservoir. This scenario typically follows the following process: First, during the feasibility study phase, initial geological borehole data is obtained through geological exploration to preliminarily delineate lithological distribution, weathered layer thickness, and the location of major fault fracture zones. After entering the construction phase, reservoir excavation proceeds from top to bottom, layer by layer and block by block, with each layer being called a construction cycle. Before the start of each construction cycle, the construction organization clarifies the planned excavation volume for that cycle, i.e., the predetermined excavation range and volume for this cycle. At the same time, the spatial location and capacity of the excavation area, filling area, transfer slag yard, and spoil disposal site are also planned through BIM model during the design phase. However, when excavation reveals the actual geological conditions, there are common problems such as the actual range of the faults revealed by excavation being much larger than the range inferred from the boreholes, and significant deviations between the weathered boundary and the initial model. This leads to the inability of traditional quantity calculation methods to accurately distinguish between effective materials and waste materials, resulting in serious discrepancies between material and inventory records.

[0013] Therefore, this embodiment provides a reservoir area earthwork quantity calculation system based on BIM and 3D reconstruction. Please refer to [link / reference]. Figure 1 ,include: The data acquisition module is used to acquire three-dimensional real-world cloud data of the reservoir area and on-site geological logging data at each stage of construction. Specifically, the data acquisition module includes a 3D real-scene acquisition unit and a geological logging mobile terminal unit; The 3D reality acquisition unit is configured to acquire 3D reality cloud data of the excavation face, transfer slag yard and filling face of the reservoir area according to the construction cycle through UAV oblique photography or LiDAR, and generate a 3D reality model with spatial coordinates. This process is achieved through existing mature 3D reconstruction technologies (such as motion recovery structure (SfM) or multi-view stereo vision (MVS). The 3D reality model is used to provide a spatial geometric benchmark for subsequent geological model updates and identification of changes in the slag heap. Specifically, the 3D reality model can accurately replicate the physical form of the construction site in a digital way. Each point in its point cloud has real geographic spatial coordinates, which allows the spatial location of the geological boundary to be accurately measured and extracted.

[0014] The geological logging mobile terminal unit is used to record lithological boundaries, weathering boundaries, fault attitudes, and the ratio of fault gouge thickness to the total exposed thickness on the excavated surface. and the percentage of clay minerals in fault gouge The longitudinal wave velocity of the rock mass obtained through on-site sonic logging tests was recorded. .

[0015] It should be noted that lithology refers to the type of rock that constitutes the rock mass, such as granite, sandstone, gneiss, etc., which determines the basic physical and mechanical properties of the rock and its engineering applicability; the lithological boundary refers to the outcrop line of the interface between different rock types on the excavated surface, which is determined by geological engineers based on visual observation; the weathering boundary refers to the outcrop line of the interface between rock masses with different degrees of weathering (such as completely weathered, strongly weathered, weakly weathered, and slightly weathered) on the excavated surface, which reflects the depth and degree of weathering force on the rock mass; and the fault attitude refers to the spatial orientation of the fault rupture surface, usually represented by three elements: strike, dip, and dip angle, which determines the extension shape of the fault zone in three-dimensional space. The so-called ratio of fault gouge thickness to total exposed thickness Specifically, the visible thickness of the fault gouge layer was measured on the excavated surface and divided by the total exposed thickness of the fault influence zone at that location to obtain a dimensionless ratio. It reflects the relative proportion of argillaceous material within the fault zone. The larger the fault, the more intense the fault activity and the worse the rock mass quality; The so-called percentage of clay minerals in fault gouge The results were determined by X-ray diffraction after on-site sampling. It reflects the weight percentage of highly hydrophilic clay minerals (such as montmorillonite and illite) in the fault gouge. The higher the clay mineral content, the stronger the tendency of the fault gouge to swell, soften, disintegrate, and become muddy after being exposed to water. So-called "drilling-while-sonic testing" refers to the real-time measurement of the longitudinal wave propagation velocity of the rock mass surrounding the borehole wall during drilling, using acoustic wave transmitting and receiving probes installed on the drill pipe; the so-called "field rock mass longitudinal wave velocity" refers to this measurement. The wave velocity obtained through this test is the reciprocal of the time it takes for a sound wave to travel through a unit length of rock mass. It comprehensively reflects the density, fissure development, and filling condition of the rock mass. The higher the wave velocity, the more complete and dense the rock mass.

[0016] The preferred geological logging mobile terminal unit is an industrial-grade tablet computer equipped with a geological sketching APP, a GPS module, and a high-resolution camera. It can directly bind the geological boundaries marked on site and the entered test data to spatial coordinates and synchronize them with the cloud database in real time.

[0017] The data acquisition module in this embodiment provides a data foundation for the subsequent construction and dynamic updating of the digital twin model by acquiring multi-source field data.

[0018] The digital twin module, connected to the data acquisition module, is used to build the design BIM model and to build and update the three-dimensional geological model using 3D real-world point cloud data and geological logging data. Based on the design BIM model and the updated three-dimensional geological model, a material identity block mesh model with material attributes is generated. Specifically, the digital twin module includes a design BIM model building unit, a 3D geological model building unit, and a material identity block grid model building unit; The design BIM model building unit is used to create the design BIM model. The design BIM model includes three-dimensional entities of the excavation area divided by elevation, three-dimensional entities of the filling area divided by the type of filling material, three-dimensional entities of each transfer slag yard and spoil disposal site, and binds the planned construction time and design volume attributes to each three-dimensional entity. It should be noted that BIM refers to Building Information Modeling, an engineering data model based on three-dimensional digital technology that integrates the geometric information, physical properties, schedule, and cost information of the project. The three-dimensional entity of the excavation area reflects the spatial range of the soil and rock mass that needs to be excavated and removed in the reservoir area according to the design drawings, and is divided into multiple sub-entities according to the construction layers. The three-dimensional entity of the filling area reflects the spatial range of each filling zone of the dam body, and is established separately according to material types such as cushion material zone, transition material zone, and main rockfill material zone. The three-dimensional entity of the transfer slag yard and waste disposal site reflects the spatial range of the area used for temporary storage of qualified materials and permanent storage of waste materials. Each three-dimensional entity is obtained by modeling operations such as stretching and lofting along the design boundary in BIM software, which is a conventional method.

[0019] The planned construction time refers to the start and end dates of each excavation layer, fill layer, and slag heap, determined according to the construction schedule network diagram. The design volume attribute refers to the geometric volume of each three-dimensional entity calculated based on the design cross-section; for fill areas, it also includes the design compaction volume for different material types. Binding is achieved by writing these attributes as key-value pairs into the attribute fields of each three-dimensional entity. For example, binding the attribute "Planned Start Time = 2025-06-01, Design Excavation Volume = 50000 m³" to the entity "3rd Excavation Layer". 3 ”; The final design BIM model reflects the idealized geometric shape, schedule target and volume benchmark of each stage of construction, and serves as the spatial coordinate framework for the entire quantity calculation system to conduct comparative analysis between the plan and the actual situation.

[0020] The three-dimensional geological model building unit is used to generate an initial three-dimensional geological model based on the initial geological borehole data through spatial interpolation. After each acquisition of a new three-dimensional real scene model and geological logging data, new geological boundary constraint points are extracted from the excavation and exposure surface of the three-dimensional real scene model. Spatial interpolation is then performed again along with the existing borehole data to dynamically update the weathering interface and fault interface. It should be noted that the initial geological borehole data refers to all geological exploration borehole data from the feasibility study stage, including borehole coordinates, borehole depth, lithological descriptions of each layer, weathering grade classification, and wave velocity test results; the initial three-dimensional geological model is in the form of a three-dimensional solid model, containing geological interface information such as the strongly weathered bottom interface, the weakly weathered bottom interface, the slightly weathered top interface, and the top and bottom spatial surfaces of each major fault fracture zone in three-dimensional space; the so-called weathering interface refers to the boundary spatial surface between the aforementioned different weathering grades; the fault interface refers to the boundary spatial surface between the fault fracture zone and the relatively intact surrounding rock on both sides; The initial three-dimensional geological model was obtained through spatial interpolation algorithms such as Kriging or radial basis functions. Specifically, the three-dimensional coordinates of the geological interface points divided within each borehole were used as known sample points, the coordinates of the borehole location were used as independent variables, and the interface elevation was used as the dependent variable. A spherical model was selected as the fitting model for the theoretical variogram to describe the spatial correlation, and an unbiased optimal estimate (ordinary Kriging) was performed on the entire reservoir area to generate a continuous geological interface surface. The selection of a spherical model as the fitting model for the theoretical variogram is a conventional method and will not be elaborated further in this embodiment. The resulting initial three-dimensional geological model reflects the optimal spatial estimate of the geological conditions of the entire reservoir area based on limited exploration data before construction.

[0021] Geological boundary constraint points refer to a series of discrete points with real three-dimensional spatial coordinates automatically extracted at specified intervals (such as 0.5 meters) along the lithological or weathering boundary lines drawn by geological engineers on the excavation surface in the new phase of the 3D reality model. The relationship between these points and the lithological boundary lines is that they are position control points that precisely define the boundary lines in three-dimensional space, transforming the boundary lines that were originally qualitatively expressed on two-dimensional drawings into quantitative constraint data that can be directly used for three-dimensional spatial interpolation calculations.

[0022] The resulting three-dimensional geological model reflects a dynamic geological entity that is constantly approaching reality as construction and excavation progresses, and can be directly verified and corrected by engineering excavation. It serves as a spatial data carrier for realizing the integration of geology and quantity calculation as excavation progresses.

[0023] The material identity block mesh model building unit is used to extract the planned excavation volume corresponding to the current construction cycle from the design BIM model. It performs a spatial Boolean intersection operation between the planned excavation volume and the updated 3D geological model, and then meshes the intersection result to generate multiple material identity blocks. Each material identity block automatically inherits lithology based on its spatial location and calculates the rock mass integrity coefficient. and fault mudification index This forms a material identity block mesh model with material attributes.

[0024] It should be noted that spatial Boolean intersection operation is an existing method, which refers to a geometric algorithm that finds the intersection between the geometric space of the planned excavation body and the geometric space of various geological bodies (such as weakly weathered granite bodies and fault fracture zones) in the three-dimensional geological model. Specifically, this operation divides the planned excavation body into several sub-blocks composed of single geological units. The lithology and weathering degree of each sub-block are uniform, ensuring that each material identification block has a clear and unique geological attribution. The process of performing three-dimensional meshing on the intersection results to generate multiple material identity blocks is as follows: For each single geological sub-block, a hexahedral-based mapped mesh or a tetrahedral free mesh is used for discretization; during the meshing, a smaller-sized (e.g., 0.5m side length) fine mesh is used at the geological body boundary (e.g., near fault edges or weathering boundaries) to ensure fitting accuracy, while a larger-sized (e.g., 2m side length) sparse mesh is used inside the homogeneous and stable rock mass to control the overall computational load. Each smallest spatial unit generated after meshing is a material identity block. It should be noted that the reason for dividing the excavation into multiple material identity blocks is that the excavation area of ​​the pumped storage reservoir is huge, but the geological conditions are highly heterogeneous in space. Only by discretizing the macroscopic excavation body into fine-grained material identity blocks can the differences in lithology, integrity, and drillability of materials at each local location be characterized, providing a refined operational object for subsequent differentiated quantity calculation, destination allocation, and quality traceability. If it is not divided, the entire excavation body can only be regarded as a homogeneous body, which cannot reflect the real complex geological conditions.

[0025] Material attributes include: the spatial centroid coordinates of the material identity block, and its natural volume. Lithology, weathering grade, and rock mass integrity coefficient Fault mudification index , as well as the subsequently bound material identification code, excavation process parameters, birth timestamp and characteristic particle size d.

[0026] Among them, rock mass integrity coefficient Calculated using the following formula: In the formula, The longitudinal wave velocity of the rock mass at the site. The longitudinal wave velocity of indoor rock blocks of the same lithology, fresh and intact; In this formula, the propagation velocity of elastic waves in rock mass is strongly influenced by the number and degree of opening of discontinuities such as fissures and joints within the rock mass. The square of the wave velocity ratio is essentially the ratio of the dynamic elastic modulus of the rock mass to that of the intact rock block, which can comprehensively characterize the degree of fissure development and structural integrity of the rock mass; the calculated... Reflects the integrity of the rock mass, with a value ranging from 0 to 1. A value close to 1 indicates that the rock mass is intact and dense. A value close to 0 indicates that the rock mass is extremely fragmented.

[0027] Among them, fault mudification index The calculation formula is: ,in, This represents the ratio of fault gouge thickness to the total exposed thickness. The percentage content of clay minerals in the fault gouge; In this formula, the degree of influence of fault gouge on engineering depends on both its geometric thickness ratio and the hydrophilicity of its material composition. The larger the value, the greater the spatial proportion of the weak interlayer in the cross-section. The higher the value, the stronger the softening and disintegration activity of the weak substance upon contact with water; multiplying the two values ​​allows for a comprehensive evaluation of the engineering hazards of fault gouge; the fault gouge index... This reflects the overall degree of fault-induced deterioration of rock mass quality, with a value ranging from 0 to 1. A value close to 1 indicates severe fault mudification, meaning the material is extremely prone to weathering and disintegration, classifying it as low-quality material. A value close to 0 indicates no impact from fault mudification, and the material quality mainly depends on the degree of weathering of the original rock.

[0028] The resulting material identity block mesh model integrates design geometric information, dynamically updated geological attributes, and fine-grained material spatial units, enabling the tracking and correlation of material quality and volume at the single-block level throughout the entire process from excavation to filling.

[0029] The digital twin module in this embodiment achieves the fusion of static design information and dynamic geological information through a three-layer progressive construction logic based on design, geology, and materials, providing the calculation engine with operation objects with complete geological semantics.

[0030] The core volume calculation engine module, connected to the digital twin module, is used to dynamically calculate the excavation volume conversion coefficient and allocate material destinations based on the material attributes in the material identity block mesh model. It performs time-dependent volume reduction calculations based on 3D reconstruction and registration for the material identity blocks allocated to the transfer slag yard, and performs volume chain conversion under the process flow state according to the material destination and time-dependent reduction results, outputting dynamic volume information. Specifically, the core computational engine module includes a material identification unit, which is used to bind a unique material identification code to each material identification block in the material identification block mesh model, and to associate the excavation process parameters, birth timestamp, and feature granularity obtained by semantic segmentation and block size analysis of the 3D real-world point cloud data with the material identification block. Together they are written into the attribute record of the material identity block.

[0031] It should be noted that the unique material identification code is used to uniquely identify and track each material identity block throughout the entire construction life cycle. It is equivalent to the digital ID card of the material block. The volume conversion, destination record and database query of all subsequent process states are indexed by this identification code; the identification code preferably adopts a globally unique identifier (UUID). The excavation process parameters refer to the rock-breaking methods and related technical indicators applied during the process of the material block changing from its original rock state to a loose state. For example, the borehole diameter, hole spacing, row spacing, explosive consumption, and detonation method during blasting excavation, or the model of the hydraulic breaker, impact power, and drill rod diameter during mechanical crushing excavation. The birth timestamp refers to the precise time when the material block is separated from the original rock matrix and officially born, recorded to the year-month-day-hour, and used for calculating the starting point of subsequent storage time. Feature granularity is obtained by semantic segmentation and block size analysis of 3D real-world point cloud data. The process is as follows: First, clustering based on region growing is performed on the slag heap point cloud to separate slag heaps from different sources or regions; then, the spatial size distribution of the stone blocks corresponding to each slag heap point cloud is statistically analyzed, and the particle size corresponding to the cumulative volume percentage reaching 50% is obtained by using the volume-weighted statistical method (i.e., calculating the equivalent sphere diameter of each stone block and plotting the cumulative distribution curve according to the volume percentage), which is the characteristic particle size of the stone heap. This characteristic particle size This reflects the actual fineness of the material after it has been blasted or mechanically crushed. A smaller value indicates more thorough crushing and finer stone size, while a larger value indicates a higher proportion of large stones.

[0032] Since the excavation process transforms the original natural rock mass into a loose mass of blocks, its volume will inevitably expand, and the degree of expansion varies depending on the integrity of the rock mass and the rock-breaking energy. Therefore, this embodiment needs to calculate the excavation volume conversion coefficient, which includes the following steps: Through formula Natural cube volume Converted to loose excavation volume ,in, The dynamic looseness coefficient, In the formula, This represents the maximum loosening coefficient of the lithology under extremely fractured conditions. The minimum integrity coefficient threshold; The process energy factor is used when the excavation process is blasting. , For the unit consumption of explosives, The baseline blasting unit consumption is used; when the excavation process is mechanical crushing... , This refers to the impact power of the hydraulic breaker. The volume of material broken per unit time. It represents the uniaxial compressive strength of the rock.

[0033] It should be noted that the maximum looseness coefficient The minimum integrity coefficient threshold is determined through indoor rock fragmentation and stacking tests. This involves completely fracturing rock fragments and freely stacking them in a graduated cylinder, measuring the ratio of the loose volume to the total volume of the rock fragments before fracturing. This ratio represents the theoretically maximum volume expansion factor achievable for that lithology; for example, 1.6 to 1.8 can be used for hard granite. The lower limit of rock mass integrity corresponding to the maximum value of the loosening coefficient is determined by statistically analyzing the measured wave velocity ratio of the most fragmented section of the rock mass in the same type of rock mass in the work area. It is usually taken as 0.1. So-called explosive unit consumption This refers to the weight of explosives consumed per cubic meter of original rock during blasting (kg / m²). 3 The baseline blasting unit consumption is determined through the blasting design documents. This refers to the reference explosive consumption per unit volume of the rock under standard blasting conditions, determined through engineering experience; the so-called uniaxial compressive strength of rock It refers to the maximum compressive stress (MPa) of a standard rock core specimen when it fails under uniaxial compression conditions, which is measured by indoor rock mechanics tests. The magnitude of the looseness coefficient originates from two factors: one is the naturally occurring fissures and pores in the rock mass (composed of...). Characterization), and secondly, externally applied rock-breaking energy (by... Characterization); in the formula, The term normalizes rock mass integrity and maps it to a fragmentation factor of 0 to 1; the more fragmented the rock mass (…), the higher the fragmentation. The lower the value, the closer the factor is to 1, and the looser the coefficient tends to its maximum value. The term represents the amplification factor of the process energy. It is set to 1 when the actual blasting energy equals the reference energy, and greater than 1 when it exceeds the reference energy, further increasing the degree of crushing and volume expansion; this yields the excavated loose volume. It reflects the actual loose accumulation volume occupied by each piece of material after it is separated from the parent rock under specific lithology and specific process conditions. It is related to specific physical conditions rather than a fixed value.

[0034] Because materials of different qualities have different engineering usability and need to be directed to different destinations, this embodiment requires allocating material destinations. This process includes: According to the preset material destination rules, each material identity block is assigned to the direct dam filling area, designated transfer slag yard or spoil disposal site in the design BIM model. Material destination rules are based on the lithology and fault mudification index of the material identity blocks. Make a judgment; When the material identity block When the value exceeds the preset fault mudification threshold, the material block is allocated to the spoil disposal site; this indicates that the material block is severely affected by fault mudification, has high disintegration and high compressibility, and even if it is stockpiled, its engineering performance as dam filling material cannot be restored, and it must be permanently disposed of as waste. when Less than or equal to the preset fault mudification threshold and rock mass integrity coefficient When the pre-set requirements for dam fill material are met, the material is allocated to the direct dam filling area or a designated transfer spoil yard; this indicates that the material is of good quality and is a usable qualified material, and it is given priority to be transported directly to the dam face filling area for compaction construction, or transported to a transfer spoil yard for temporary storage for subsequent filling use; the pre-set requirements for dam fill material are determined according to the material type standards of different filling areas, such as the requirements for cushion layer material. >0.75, Transition Material Requirements >0.6, Requirements for main pile stones >0.5, etc., are not limited in this embodiment; when Below the preset requirements for dam material and When the material does not meet the waste material standard, it is allocated to a designated transfer slag yard as a reserve for subsequent mining. This indicates that the quality of the material is between qualified material and waste material. Although it does not meet the criteria for direct application to the dam, it still has certain engineering utilization value. After temporary storage in the slag yard and possible secondary screening or selective mining, it can still be used as filling material for secondary rockfill areas or slope protection and other secondary parts.

[0035] Because materials stored in transit spoil heaps undergo deterioration processes such as surface weathering, softening from rainwater infiltration, and mud mixing due to long-term exposure to the surface environment, the effective volume that can actually be used for dam filling decreases over time. Therefore, this embodiment requires performing a time-dependent volume reduction calculation on the material identity blocks allocated to the transit spoil heaps based on three-dimensional reconstruction and registration. This process includes: Regularly acquire the latest 3D point cloud data of the transfer slag yard, spatially register the new 3D point cloud data with the historical 3D point cloud data, and identify newly added and removed stockpiles through point cloud differential analysis. It should be noted that spatial registration refers to aligning two sets of point cloud data to the same coordinate system using the Iterative Closest Point (ICP) algorithm; point cloud differential identification refers to calculating the spatial distance between corresponding regions of the two sets of point clouds after registration, and determining that a new stack is added when a significant positive difference appears in a certain region.

[0036] This step is used to dynamically identify changes in the stockpiling and unloading of slag yards, determine which material identity blocks still remain in the slag yard and which have been transported away, thereby determining the currently effective set of objects for the time-deduction calculation and avoiding incorrect calculations for materials that no longer exist.

[0037] For each material identification block currently still stockpiled in the slag yard The storage time is determined based on the entry timestamp associated with its material identification code. The effective usable loose volume after stacking is calculated using the following formula. :

[0038] In the formula, For the first The initial loose volume of each material identity block upon entry. For the first The fault mudification index corresponding to each material identification block For the first The feature particle size corresponding to each material identity block The weathering environment constant is determined by indoor rock block wet-dry cycle test; It should be noted that the weathering environment constant The rate coefficient representing the rate at which the weathered and deteriorated layer on the surface of the rock mass advances inward under local climatic conditions is expressed in m / √day. It is obtained by placing standard rock blocks of the same lithology in an on-site slag yard environment or a simulated wet-dry cycle environment, periodically measuring their mass loss and surface deterioration depth, and fitting a curve showing the relationship between deterioration depth and time. The value is usually taken as 0.001~0.005.

[0039] The weathering and deterioration of rock blocks is a diffusion-controlled process that progresses gradually from the surface inwards, and its weathering depth... Over time The growth pattern is approximately as follows: ,in As a mud-forming sensitivity factor, it can accelerate or slow down this process; for characteristic particle sizes of The equivalent spherical rock block, its volume The specific surface area is proportional to the cube of the diameter, and the surface area is proportional to the square of the diameter; therefore, the specific surface area is... ; after time Then, the thickness deteriorates from the surface inwards. The outer shell layer, the volume loss rate corresponding to this deteriorated layer is approximately... (Based on a first-order approximation of the spherical shell volume); therefore, the retention rate of the remaining effective volume is... The final effective usable loose volume is obtained. This represents the remaining loose volume of the material after it has been stored and weathered, and after removing the surface deterioration and muddy layers, the interior still retains the original engineering quality and can be used for dam filling.

[0040] Identify all material blocks in the transfer slag yard that meet the conditions for recovery. The total available loose volume of each type of qualified material at the slag heap is obtained by summing the results according to material type. This step provides construction managers with a dynamically updated and accurate inventory list of available material sources, directly guiding the dam filling material preparation plan and avoiding material shortages or scheduling errors.

[0041] Because the material undergoes multiple processes from its natural state to the final compacted state of the dam surface, its volume state constantly changes, requiring systematic conversion according to the process chain. Therefore, this embodiment performs a volume chain conversion based on the material's destination and time-related reduction results, which includes: Based on the allocation and destination of the material identity blocks, the volume conversion for each state is automatically performed along the construction process chain; For the direct access route to the dam, the effective compaction volume Convert using the following chain method:

[0042] For the route of mining back to the dam after transshipment and storage, the effective compaction volume Convert using the following chain method:

[0043] in, The effective loose volume after aging reduction. The settlement coefficient during a single transport operation. This is the secondary transport settlement coefficient. This is the compaction coefficient for a single rolling pass. This represents the secondary compaction coefficient.

[0044] It should be noted that the settlement coefficient during a single transport is... The representative material represents the reduction in loose volume due to bumps, vibrations, and compaction under its own weight after being loaded onto trucks at the excavation face and transported to the dam face or transfer spoil heap. Based on experience, an optimal value range of 0.95~1.00 is selected, meaning the loose volume may shrink by 0%~5% due to transportation settlement. The longer the transportation distance and the worse the road conditions, the smaller the value should be. The secondary transportation settlement coefficient... This represents the volume reduction ratio during the secondary mining, loading, and transportation of spoil from the transfer slag yard to the dam surface. Similarly, values ​​are determined empirically, with the optimal range being [missing information]. Consistent; Compaction coefficient of a single rolling mill The volume conversion ratio for achieving the designed compaction density after the loose material delivered to the dam surface undergoes a specified number of compaction passes is preferred, with an empirical range of 1.15~1.35; the secondary compaction coefficient... This represents the compaction characteristics of the recovered material after secondary compaction. Because the recovered material has undergone a period of stockpiling and compaction, and possibly secondary crushing, its compaction characteristics may differ from those of freshly excavated material. Based on the same experience, the value is determined to be slightly smaller than... .

[0045] For direct access routes to the dam, since the material is excavated and filled in one continuous process without any storage time delay or weathering reduction, the natural volume is directly converted to compacted volume using the chain formula described above. For access routes involving transshipment and storage followed by mining to the dam, since the material undergoes weathering reduction in the spoil heap, its usable volume starting point is no longer the original loose volume upon entry, but rather the reduced effective loose volume. Therefore, the chain formula is based on Starting from the point, after secondary transportation settlement and secondary rolling compaction, the final effective compaction volume is calculated.

[0046] The final output dynamic volume information includes: the loose volume of each material identification block in the excavation state, the effective usable loose volume in the transfer slag yard storage state, the effective compacted volume filled to the dam surface after process flow, and various sub-item volumes classified and statistically analyzed according to destination and quality attributes; this information reflects the true usable volume status of materials under the dynamic changes of three factors: geological exposure, construction technology and environmental time aging, throughout the entire process from excavation to filling.

[0047] The core quantity calculation engine module in this embodiment realizes the dynamic calculation of material quality and quantity within the cycle through a five-step process: identity identification, dynamic loosening, destination allocation, time efficiency reduction, and process conversion. This changes the defect of separating quality and quantity in traditional quantity calculation methods.

[0048] The visualization application module, connected to the core quantity calculation engine module, is used to overlay and display the material identity block grid model and its dynamic volume information in the BIM 3D view.

[0049] Specifically, the visualization application modules include: The overlay display unit is used to overlay the material identification block grid model onto the 3D view of the design BIM model, using different colors to represent the lithology, weathering degree, and effective material / waste determination results of each material identification block; for example, light red represents the fully weathered waste area, light green represents the weakly weathered qualified material area, and dark red represents the fault muddy waste area, so that construction personnel can have a clear view of the material quality distribution in front of the tunnel face. The slag yard material status display unit is used to represent the remaining effective volume ratio of each material identity block on the slag yard three-dimensional real scene model based on the results of the time-dependent volume reduction calculation. For example, fresh material that has just entered the yard is displayed as an opaque entity. As the storage time goes by and the effective volume decreases, the transparency gradually increases. When the effective volume ratio of a certain material drops below the design threshold, it is indicated with high transparency or warning color that the material is no longer suitable for the original design purpose.

[0050] Example 2: This example provides a method for calculating earthwork volume in a reservoir area based on BIM and 3D reconstruction. Please refer to [link / reference]. Figure 2 ,include: Step S1: Periodically collect three-dimensional real-time cloud data of the excavation face, slag yard and filling face of the reservoir area to obtain geological logging and wave velocity test data of the rock mass exposed by excavation; Step S2: Construct a design BIM model including the excavation area, filling area and slag yard; generate an initial three-dimensional geological model based on the initial borehole data; and update the geological interface in the three-dimensional geological model using the three-dimensional real-world point cloud data and geological logging data of each period. Step S3: Extract the planned excavation body corresponding to the current construction cycle from the design BIM model, perform spatial Boolean operation with the updated three-dimensional geological model, and perform three-dimensional meshing on the operation results to generate material identity blocks with unique identifiers. Each material identity block automatically inherits lithology and calculates the rock mass integrity coefficient and fault mudification index. Step S4: Calculate the dynamic loosening coefficient based on the rock mass integrity coefficient and excavation process parameters of the material identity block, convert the natural volume into loose volume, and allocate the material identity block to the direct dam area or intermediate slag yard in the design BIM model according to the fault mudification index and preset destination rules. Step S5: For material identification blocks destined for the transfer slag yard, write their initial loose volume, characteristic particle size, fault mudification index and entry timestamp into the database, and dynamically update the pile morphology and characteristic particle size through registration and segmentation of multi-phase slag yard three-dimensional real-world point cloud. Step S6: Periodically call the time-deduction model to calculate the effective usable loose volume of each material identity block in the slag yard after the storage time, and summarize the total amount of each type of qualified material; when the back mining is carried out, match the material identity blocks according to the dam filling material requirements, and convert them into effective compacted volume in combination with the rolling compaction coefficient. Step S7: Display the volume, quality, and destination information of the material identification blocks on the visualization interface of the BIM model design.

[0051] This embodiment, through the above steps, connects on-site 3D real-scene perception, dynamic geological modeling, fine-grained material identification, and dynamic volume conversion and time-effect reduction algorithms based on physical mechanisms. It solves the problems of the separation between geological model and calculation model, fixed and rigid volume conversion coefficient, and inability to trace the destination and quality of materials in the traditional earthwork calculation of pumped storage reservoir areas, and realizes the accounting of the entire process from excavation to filling.

[0052] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A reservoir area earthwork calculation system based on BIM and 3D reconstruction, characterized in that, include The data acquisition module is used to acquire three-dimensional real-world cloud data of the reservoir area and on-site geological logging data at each stage of construction. The digital twin module, connected to the data acquisition module, is used to construct the design BIM model and, using the three-dimensional real-world point cloud data and geological logging data, construct and update the three-dimensional geological model. Based on the design BIM model and the updated three-dimensional geological model, a material identity block mesh model with material attributes is generated. The core volume calculation engine module, connected to the digital twin module, is used to dynamically calculate the excavation volume conversion coefficient and allocate material destinations based on the material attributes in the material identity block grid model. It performs time-dependent volume reduction calculations based on three-dimensional reconstruction and registration for the material identity blocks allocated to the transfer slag yard, and performs volume chain conversion under the process flow state based on the material destination and time-dependent reduction results, and outputs dynamic volume information. The visualization application module, connected to the core quantity calculation engine module, is used to overlay and display the material identity block grid model and its dynamic volume information in the BIM 3D view.

2. The reservoir area earthwork calculation system according to claim 1, characterized in that, The data acquisition module includes: The 3D reality acquisition unit is configured to acquire 3D reality cloud data of the excavation face, transfer slag yard and filling face of the reservoir area according to the construction cycle through UAV oblique photography or LiDAR, and generate a 3D reality model with spatial coordinates. The geological logging mobile terminal unit is used to record lithological boundaries, weathering boundaries, fault attitudes, and the ratio of fault gouge thickness to the total exposed thickness on the excavated surface. and the percentage of clay minerals in fault gouge The longitudinal wave velocity of the rock mass obtained through on-site sonic logging tests was recorded. .

3. The reservoir area earthwork calculation system according to claim 2, characterized in that, The digital twin module includes: The design BIM model building unit is used to build the design BIM model. The design BIM model includes three-dimensional entities of the excavation area divided by elevation, three-dimensional entities of the filling area divided by the type of filling material, three-dimensional entities of each transfer slag yard and spoil disposal site, and binds the planned construction time and design volume attributes to each three-dimensional entity. The three-dimensional geological model construction unit is used to generate an initial three-dimensional geological model based on the initial geological borehole data through spatial interpolation. After each acquisition of a new three-dimensional real scene model and geological logging data, new geological boundary constraint points are extracted from the excavation and exposure surface of the three-dimensional real scene model. Spatial interpolation is then performed again along with the existing borehole data to dynamically update the weathering interface and fault interface. The material identity block mesh model construction unit is used to extract the planned excavation volume corresponding to the current construction cycle from the design BIM model, perform a spatial Boolean intersection operation between the planned excavation volume and the updated three-dimensional geological model, and perform three-dimensional meshing on the intersection result to generate multiple material identity blocks. Each material identity block automatically inherits lithology according to its spatial location and calculates the rock mass integrity coefficient. and fault mudification index This forms a material identity block mesh model with material attributes.

4. The reservoir area earthwork calculation system according to claim 3, characterized in that, The core computational engine module includes a material identification unit, used to bind a unique material identification code to each material identification block in the material identification block grid model, and to assign the excavation process parameters, birth timestamp, and feature granularity obtained by semantic segmentation and block size analysis of the three-dimensional real-world point cloud data to the material identification block. Together they are written into the attribute record of the material identity block.

5. The reservoir area earthwork calculation system according to claim 4, characterized in that, The calculation of the excavation volume conversion factor includes: Through formula Natural cube volume Converted to loose excavation volume ,in, The dynamic looseness coefficient, In the formula, This represents the maximum loosening coefficient of the lithology under extremely fractured conditions. The minimum integrity coefficient threshold; the rock mass integrity coefficient Calculated using the following formula: In the formula, The longitudinal wave velocity of the rock mass at the site is given. The longitudinal wave velocity of indoor rock blocks of the same lithology, fresh and intact; The process energy factor is used when the excavation process is blasting. , For the unit consumption of explosives, The baseline blasting unit consumption is used; when the excavation process is mechanical crushing... , This refers to the impact power of the hydraulic breaker. The volume of material broken per unit time. It represents the uniaxial compressive strength of the rock.

6. The reservoir area earthwork calculation system according to claim 5, characterized in that, The allocation of material destinations includes: according to preset material destination rules, allocating each material identity block to the direct dam filling area, designated transfer slag yard, or spoil disposal site in the design BIM model; The material destination rules are based on the lithology and fault mudstone index of the material's identity block. The fault mudification index was determined. The calculation formula is: ,in, This represents the ratio of fault gouge thickness to the total exposed thickness. The percentage content of clay minerals in the fault gouge; When the material identity block When the value exceeds the preset fault mudification threshold, the material identification block is allocated to the spoil disposal site; when... Less than or equal to the preset fault mudification threshold and rock mass integrity coefficient When the pre-set requirements for dam material are met, it is allocated to the direct dam filling area or a designated transfer spoil disposal site; when Below the preset requirements for dam material and If the waste material does not meet the disposal criteria, it will be allocated to a designated transfer slag yard for subsequent recycling.

7. The reservoir area earthwork calculation system according to claim 6, characterized in that, The calculation of time-dependent volume reduction for material identity blocks allocated to the transit slag yard based on 3D reconstruction registration includes: Regularly acquire the latest 3D point cloud data of the transfer slag yard, spatially register the new 3D point cloud data with the historical 3D point cloud data, and identify newly added and removed stockpiles through point cloud differential analysis. For each material identification block currently still stockpiled in the slag yard The storage time is determined based on the entry timestamp associated with its material identification code. The effective usable loose volume after stacking is calculated using the following formula. : In the formula, For the first The initial loose volume of each material identity block upon entry. For the first The fault mudification index corresponding to each material identification block. For the first The feature particle size corresponding to each material identity block. The weathering environment constant is determined by indoor rock block wet-dry cycle test; Identify all material blocks in the transfer slag yard that meet the conditions for recovery. The total effective usable loose volume of all types of qualified materials at the slag yard is obtained by summing the results according to the material type.

8. The reservoir area earthwork calculation system according to claim 7, characterized in that, The volume chain conversion under the process flow state based on material destination and time-deduction results includes: Based on the allocation and destination of the material identity blocks, the volume conversion for each state is automatically performed along the construction process chain; For the direct access route to the dam, the effective compaction volume Convert using the following chain method: For the route of mining back to the dam after transshipment and storage, the effective compaction volume Convert using the following chain method: in, The effective loose volume after aging reduction. The settlement coefficient during a single transport operation. This is the secondary transport settlement coefficient. This is the compaction coefficient for a single rolling pass. This represents the secondary compaction coefficient.

9. The system according to claim 1, characterized in that, The visualization application module includes: The overlay display unit is used to overlay the material identity block grid model onto the three-dimensional view of the design BIM model, and use different colors to represent the lithology, weathering degree, and effective material / waste determination result of each material identity block; The slag yard material status display unit is used to represent the percentage of the remaining effective volume of each material identity block on the slag yard three-dimensional real-scene model with transparency based on the result of the time-effect volume reduction calculation.

10. A method for calculating earthwork volume in reservoir areas based on BIM and 3D reconstruction, characterized in that, Includes the following steps: Step S1: Periodically collect three-dimensional real-time cloud data of the excavation face, slag yard and filling face of the reservoir area to obtain geological logging and wave velocity test data of the rock mass exposed by excavation; Step S2: Construct a design BIM model including the excavation area, filling area and slag yard; generate an initial three-dimensional geological model based on the initial borehole data; and update the geological interface in the three-dimensional geological model using the three-dimensional real-world point cloud data and geological logging data of each period. Step S3: Extract the planned excavation body corresponding to the current construction cycle from the design BIM model, perform spatial Boolean operation with the updated three-dimensional geological model, and perform three-dimensional meshing on the operation result to generate material identity blocks with unique identifiers. Each material identity block automatically inherits lithology and calculates the rock mass integrity coefficient and fault mudification index. Step S4: Calculate the dynamic loosening coefficient based on the rock mass integrity coefficient and excavation process parameters of the material identity block, convert the natural volume into loose volume, and allocate the material identity block to the direct dam area or intermediate slag yard in the design BIM model according to the fault mudification index and preset destination rules. Step S5: For material identification blocks destined for the transfer slag yard, write their initial loose volume, characteristic particle size, fault mudification index and entry timestamp into the database, and dynamically update the pile morphology and characteristic particle size through registration and segmentation of multi-phase slag yard three-dimensional real-world point cloud. Step S6: Periodically call the time-deduction model to calculate the effective usable loose volume of each material identity block in the slag yard after the storage time, and summarize the total amount of each type of qualified material; when the back mining is carried out, match the material identity blocks according to the dam filling material requirements, and convert them into effective compacted volume in combination with the rolling compaction coefficient. Step S7: Display the volume, quality, and destination information of the material identification blocks on the visualization interface of the BIM model design.

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