A method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling

Abstract

The application discloses a method for determining effective volume of bulk material pile based on three-dimensional parameterized modeling, and aims at solving the problem of complicated measurement process of the existing bulk material effective volume. The method comprises the following steps: constructing a natural accumulation pile model in modeling software; cutting the natural accumulation pile model according to the actual arrangement size of the material blocking surface of the material blocking wall and taking the material blocking surface of the material blocking wall as a cutting surface; constructing a discharge model according to the arrangement size of the actual discharge port, wherein the height of the discharge model is greater than or equal to the height of the natural accumulation pile model; taking the cut natural accumulation pile model as a target body, taking the discharge model as a tool body, and performing Boolean operation on the target body and the tool body to obtain an effective volume model by intersection; and performing volume operation on the effective volume model by using a measurement tool in the modeling software. The measurement process is relatively simple, the work burden of the designer is relatively light, and the measurement result is relatively high in accuracy.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and more specifically, to a method for determining the effective volume of bulk material piles based on three-dimensional parametric modeling. Background Technology

[0002] In building construction, mining, and hydropower projects, bulk materials such as sand and gravel aggregates are typically piled into relatively regular shapes. Because there are various types of material feeding methods for these piles, including point-type (single-point, double-point, and multi-point), strip-type, and point-strip mixed types, the corresponding pile shapes are mainly conical (single-peak, double-peak, and multi-peak), elongated, and various combinations of both. Retaining walls are usually installed at a certain depth along the natural slope of the pile to save space. When using a bottom-mounted material extraction method, due to the material's natural angle of repose and unloading angle, the areas between the unloading ports and between the unloading ports and the retaining walls become dead material zones that accumulate over time, thus reducing the actual usable volume of the pile. Various industry design manuals provide empirical formulas and tables for calculating the effective volume of material piles. However, these formulas and table lookup methods are relatively complex. In practice, designers often manually estimate the effective volume of the material pile using CAD-aided drafting. Because material piles naturally form conical surfaces, manual estimations often result in inaccurate handling of corners and discharge ports, or simply proportional calculations. This leads to inaccurate and slow calculations, and discharge port arrangements based on experience and simple calculations do not achieve optimal utilization of the pile's volume. Therefore, there is an urgent need for a method that can quickly and accurately determine the effective volume of a material pile, reducing the workload of designers and ensuring more reliable measurement results. Summary of the Invention

[0003] This invention provides a method for determining the effective volume of bulk material piles based on three-dimensional parametric modeling. The method uses three-dimensional auxiliary software to simulate the actual spatial shape of bulk material piles and constructs a spatial model of the effective volume based on the unloading characteristics of bulk materials. Then, the three-dimensional auxiliary software is used to solve the volume of the spatial model of the effective volume, and finally the effective volume data is obtained. This avoids the process of looking up tables and estimation, and ensures the accuracy of the measurement results.

[0004] This invention is achieved through the following technical solution:

[0005] A method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling includes the following steps:

[0006] Construct a natural stockpile model in modeling software;

[0007] The natural accumulation material pile model is cut using the retaining surface of the retaining wall as the cutting surface and according to the actual layout dimensions of the retaining wall.

[0008] A discharge model is constructed based on the actual discharge port layout dimensions, wherein the height of the discharge model is greater than or equal to the height of the natural stockpile model;

[0009] Using the cut natural stockpile model as the target body and the unloading model as the tool body, Boolean operations are used to find the intersection of the target body and the tool body to obtain the effective volume model;

[0010] The effective volume model is calculated using the measurement tools in the modeling software.

[0011] In some implementations, constructing a natural stockpile model includes the following steps:

[0012] Construct the first stockpile model;

[0013] Construct a second stockpile model;

[0014] The natural stockpile model is obtained by splicing and summing the first stockpile model and the second stockpile model.

[0015] In some implementations, the first stockpile model is a cone-shaped stockpile model.

[0016] In some embodiments, the second stockpile model is a long strip stockpile model.

[0017] In some implementations, the first stockpile sub-model and the second stockpile sub-model are stored as a sub-model library.

[0018] In some implementations, constructing the unloading model includes the following steps:

[0019] Parametricize the discharge port and create a parametric planar profile of the discharge port in the modeling software;

[0020] A stretching feature is established based on the outline of the discharge port, wherein the stretching height is greater than the height of the natural stockpile model.

[0021] The unloading model is obtained by drawing the side of the stretching feature using the self-unloading angle of the target bulk material as the draft angle.

[0022] In some implementations, if there are multiple unloading ports in the actual site, after constructing the unloading model, the unloading model is arranged into a rectangular array according to the spacing between the unloading ports in the actual site, and the set of unloading models obtained by the rectangular array is intersected with the natural stockpile model.

[0023] In some implementations, the length, width, and planar coordinates of the discharge port are parameterized.

[0024] In some implementations, when the profile of the discharge port lies within the orthographic projection profile of the natural stockpile model, all sides of the stretching feature are drafted to obtain the discharge model.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] 1. This invention provides a method for determining the effective volume of bulk material piles based on three-dimensional parametric modeling. It utilizes three-dimensional auxiliary software to model a real natural stockpile and the dead zone at the discharge port, ultimately obtaining a spatial model of the effective volume. The powerful calculation tools in the three-dimensional auxiliary software are then used to measure the volume of the spatial model of the effective volume to obtain the actual effective volume. This avoids the previously tedious table lookup work and reduces the intervention of subjective human factors, such as estimation and proportional value selection. The resulting effective volume is more accurate, and the workload of designers is relatively reduced.

[0027] 2. The present invention provides a method for determining the effective volume of bulk material piles based on three-dimensional parametric modeling. By adjusting the dimensional parameters in the three-dimensional model, natural stockpile models and unloading models of different sizes can be quickly obtained, thereby realizing the rapid measurement of the effective volume of stockpiles of different sizes. That is, the method is applicable to various application scenarios. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the cross-sectional structure of an actual natural stockpile.

[0030] Figure 2 This is a schematic diagram of the method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling, as provided in an embodiment of the present invention.

[0031] The attached diagram shows the markings and corresponding component names:

[0032] 1-Effective volume area, 2-Dead zone for material stacking, 3-Retaining wall, 4-Discharge port. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0034] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0035] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0036] In the description of this invention, the terms "front," "rear," "left," "right," "up," "down," "vertical," "horizontal," "high," "low," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0037] like Figure 1 The diagram shows a cross-sectional view of the actual natural stockpile within the retaining wall 3. The retaining wall 3 is set on the ground and encloses a certain area. The loose material within the retaining wall 3 consists of an effective volume area 1 and a stockpile dead area 2. The loose material in the effective volume area 1 can be discharged automatically from the discharge port 4, while the loose material in the stockpile dead area 2 is always located within the area enclosed by the retaining wall 3.

[0038] like Figure 2 As shown in the figure, an embodiment of the present invention provides a method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling, comprising the following steps:

[0039] S1. Construct a natural stockpile model in modeling software.

[0040] The natural packing shape of bulk materials is mostly conical. When building a model of a naturally packed material pile, the taper of the pile after it is formed can be obtained based on the angle of repose. This taper can then be used as a reference dimension for model building. Incorporating the angle of repose into the dimensional reference allows for a more accurate simulation of the actual packing shape of a type of bulk material, thus avoiding repeated dimensional measurements. Of course, in cases with significant individual differences, actual dimensional measurements can be performed. Specifically, when the packing shape of a particular bulk material deviates significantly from the empirically derived packing shape (e.g., an angle of repose difference of more than 2 degrees), the actual packing shape of that bulk material can be measured separately. This ensures a high degree of agreement between the model and the actual packing shape, guaranteeing the accuracy of the measured effective volume value.

[0041] It is understood that the modeling software used in this application can be any BIM modeling software.

[0042] It should be noted that the angle of repose is the minimum angle between the horizontal surface and the inclined plane when an object placed on it is in a critical state of sliding down the inclined plane (i.e., as the angle of inclination increases, the object on the inclined plane will slide down more easily; the angle at which the object reaches the state of starting to slide down is called the angle of repose). Of course, depending on the moisture content, particle size distribution, etc., the same type of bulk material may have different angles of repose. Therefore, before modeling the component, parameters such as the moisture content and particle size distribution of the bulk material in the corresponding area can be measured.

[0043] Since there are various ways to stack bulk materials, such as long strips, cones, or a combination of long strips and cones, the measurement process is usually not smooth and may introduce a certain amount of estimation. At the same time, the software itself has a certain degree of precision, and errors may be further introduced during the model generation process. This will result in a large difference between the generated model and the actual spatial shape of the material pile. Therefore, in some embodiments of this application, the actual spatial shape of the material pile can be split, for example, into a standard long strip and a standard cone, and then a first material pile sub-model and a second material pile model can be constructed respectively. During the construction process, the dimensional accuracy of the interface between the two material pile sub-models needs to be ensured. Then, the first material pile model and the second material pile model are combined to obtain a natural stacking material pile model. By establishing the model in this way, the modeling difficulty can be appropriately reduced, and the model has a higher degree of consistency with the actual material pile. In practice, based on the typical shape of the stockpile, the first stockpile sub-model can be a conical sub-model, and the second stockpile model can be a long strip sub-model. During the creation of the natural stockpile model, parameters can be adjusted for each individual first stockpile sub-model to fit the actual size of the natural stockpile model, or parameters can be adjusted for each individual second stockpile model. After each construction of the first and second stockpile sub-models, they can be stored in a model library. In subsequent modeling processes, if the size of the actual natural stockpile is the same as or has a high degree of overlap with the size of the stockpile sub-model in the model library, the sub-model can be directly called from the library. This avoids or reduces the amount of parameter adjustment, thereby reducing modeling work and alleviating the workload of designers. It also improves the efficiency of effective volume measurement to some extent.

[0044] S2. Cut the natural accumulation material pile model using the retaining surface of the retaining wall as the cutting surface and according to the actual layout dimensions of the retaining wall.

[0045] Bulk materials are typically contained within retaining walls to restrict their accumulation area. This is because the closer the bulk material is to the ground, the less effective the accumulation volume tends to be; retaining walls can improve space utilization to some extent. Depending on the specific arrangement and structure of the retaining wall, the shape of the retaining surface varies. For example, if the retaining wall is perpendicular to the ground and its overall shape is a cuboid, then the retaining surface is a vertical plane relative to the ground. If the retaining wall is at an angle to the ground and its overall shape is a cuboid, then the retaining surface is an oblique plane relative to the ground. Correspondingly, the cut surface generated when cutting a model of naturally accumulated material from this type of retaining surface is a wedge-shaped surface. Of course, depending on different functional requirements, the shape of the retaining surface on the retaining wall may also be irregular, such as curved or pleated. For ease of measurement, the retaining surface of the retaining wall is usually set as a plane, and the retaining surface is perpendicular to the ground.

[0046] S3. Construct a discharge model based on the actual discharge port layout dimensions, wherein the height of the discharge model is greater than or equal to the height of the natural stockpile model.

[0047] Specifically, the arrangement dimensions of the discharge port vary depending on the type of discharge port. For example, in some embodiments, the discharge port may be a rectangular opening. The arrangement dimensions of the discharge port include its length, width, and coordinate dimensions in the plane. Based on the length and width of the discharge port, the planar outline of the discharge port can be constructed first. Then, the planar outline is stretched to form a columnar body with a height greater than that of the natural stockpile model. If the entire outline of the discharge port is located within the actual natural stockpile, the four sides of the columnar body are drafted. The draft angle is determined based on the self-discharge angle of the bulk material. The spatial position of the solid after drafting is adjusted according to the coordinate dimensions in the plane to ensure that the relative position of the discharge model and the natural stockpile model matches the actual situation.

[0048] In some implementations, the outline of the discharge port is not necessarily entirely within the actual natural stockpile. For example, the discharge port is set as a rectangle, and the long side of the rectangle is extended throughout the actual natural stockpile. In this case, when drafting the column, only the two sides corresponding to the two long sides of the column need to be drafted to form the discharge model.

[0049] S4. Using the cut natural stockpile model as the target body and the unloading model as the tool body, the effective volume model is obtained by performing Boolean operations to find the intersection of the target body and the tool body.

[0050] As long as the unloading model corresponds to the unloading port, the bulk material represented by the unloading model can be completely unloaded from the unloading port. The structure obtained by performing Boolean operation on the unloading model and the natural stockpile model is the amount of bulk material that can be unloaded from the unloading port in the natural stockpile model, which is the effective volume model.

[0051] S5. Use the measurement tools in the modeling software to perform volume calculations on the effective volume model.

[0052] If there are multiple unloading ports in the actual site, and all unloading ports are arranged according to certain rules, after generating one unloading model, other unloading models can be generated at once using array features. For example, in some implementations, if there are multiple unloading ports in the actual site, after constructing the unloading model, the unloading model is arranged in a rectangular array according to the spacing between the unloading ports in the actual site. The set of unloading models obtained by the rectangular array is intersected with the natural stockpile model to obtain the effective volume model.

[0053] In some implementations, the length, width, and planar coordinates of the discharge port are parameterized. This setting facilitates the adjustment of the discharge port to adapt to the construction of stockpile models under different bulk material and site conditions.

[0054] Based on the above, the modeling process of this application parameterizes the angle of repose and the unloading angle to calculate the volume of different types of material piles; the parameterization of other main control dimensions enables the effective volume to be calculated by flexibly adjusting the pile layout, quickly determining the optimal arrangement of the unloading port, and improving the efficiency of repeated optimization of the pile layout in process design; there are interrelated intrinsic relationships among the parameters, such as the close relationship between the pile height, the material unloading angle, and the spacing between the discharge ports, which together determine the effective volume of the pile, and setting multiple parameters facilitates flexible adjustment.

[0055] It should be noted that the method proposed in this application is not limited to a single BIM software, but has the general applicability of BIM software. It is a method for optimizing the design of bulk material stacking using BIM software, which makes up for the shortcomings of traditional design that does not pay attention to the accurate design of non-standard models such as bulk material stacking, and has a certain degree of applicability.

[0056] The following is an application example of effective volume measurement based on the 3DE platform.

[0057] The first step is to determine the basic parameters:

[0058] First, based on literature review and engineering practice, the basic parameters of the sand and gravel aggregate were determined: the angle of repose was 37°, and the self-unloading angle was 45°. Then, considering the overall layout of the sand and gravel system, a long, strip-shaped stockpile was adopted for the single-type aggregate. The overall shape can be summarized as a triangular prism in the middle, with two semi-conical ends connecting to the prism along its height. The initial stockpile height was 12m, the distance between retaining walls was 24m, and the top of the stockpile was unloaded using a strip-type unloading trolley. The middle unloading section was 11m long.

[0059] Step 2: Establish a natural stockpile model:

[0060] Based on the 3DE platform, a right triangle sketch with an initial acute angle of 37° is created. The length of the opposite side of the acute angle is the height of the material pile, and this opposite side is used as the axis of rotation. The initial value is 12m. At the same time, the height of the material pile and the angle of repose are parameterized for easy adjustment.

[0061] Using the other acute-angle vertex as the drop point, a 180° rotating envelope is established based on the rotation axis to create a semi-conical material pile model for natural accumulation at one end of the drop point. The triangular section of the rotated semi-conical shape is extracted and extruded into a triangular prism. The extruded length is the length of the conveyor belt unloading section at the top of the material pile, initially set to 11m, and the extruded length is parameterized. Then, the semi-conical material pile is symmetrical about the central normal of the triangular prism to create a semi-conical material pile model for natural accumulation at the other end of the drop point. The above three envelope models are added and combined to establish a long strip material pile model.

[0062] Step 3: Establish models of the retaining wall and unloading port, and calculate the effective volume using the natural stockpile model.

[0063] 1) The retaining wall is simplified into a cutting surface. The initial distance between the two surfaces is 24m. This distance is parameterized symmetrically about the central face of the triangular prism. The central face of the triangular prism is used as the position reference, and the distance between the cutting surfaces is used as the constraint symmetrical cutting of the material pile model.

[0064] 2) Based on engineering experience, the material pile is considered to use 3 rows of discharge ports. Taking one corner of the arrangement of all discharge ports as the position reference point, the planar profile of the discharge ports is established at the reference point. The initial values ​​of the length and width of the discharge ports are both 2m. The initial value of the longitudinal distance from the end unloading point section is set to 5.3m, and the initial value of the transverse distance from the central axis of the pile is set to 5.0m. The length, width and planar coordinates of the discharge ports are parameterized. An extrusion feature is established based on the planar profile of the discharge ports. The extrusion length is the same as the height of the material pile and is parameterized in conjunction with it. Then, a draft model is established using a 45° self-unloading angle as the draft angle to simulate the effective volume area of ​​a single discharge port, i.e., the unloading model. The draft angle is parameterized to adapt to the characteristics of different materials and different self-unloading angles.

[0065] 4) The draft model of a single discharge port is modeled using a parameterized rectangular array. The initial values ​​of the spacing between rows in the example are set to 5m and 8m respectively, to complete the modeling of the discharge port layout.

[0066] 5) Solve the effective volume model by intersecting the above rectangular array with the naturally stacked material pile model. Use the measurement tools provided by 3DE to read the volume of the effective volume model. Based on the initial values, the effective volume is calculated to be 3314.45 m³. 3 .

[0067] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling, characterized in that, Includes the following steps: Construct a natural stockpile model in modeling software; The natural accumulation material pile model is cut using the retaining surface of the retaining wall as the cutting surface and according to the actual layout dimensions of the retaining wall. A discharge model is constructed based on the actual discharge port layout dimensions, wherein the height of the discharge model is greater than or equal to the height of the natural stockpile model; Using the cut natural stockpile model as the target body and the unloading model as the tool body, Boolean operations are used to find the intersection of the target body and the tool body to obtain the effective volume model; The effective volume model was calculated using the measurement tools in the modeling software. The process of constructing the unloading model also includes the following steps: Parametricize the discharge port and create a parametric planar profile of the discharge port in the modeling software; A stretching feature is established based on the outline of the discharge port, wherein the stretching height is greater than the height of the natural stockpile model. The unloading model is obtained by drawing the side of the stretching feature using the self-unloading angle of the target bulk material as the draft angle.

2. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 1, characterized in that, The steps involved in constructing a natural stockpile model are as follows: Construct the first stockpile model; Construct a second stockpile model; The natural stockpile model is obtained by splicing and summing the first stockpile model and the second stockpile model.

3. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 2, characterized in that, The first material pile model is a cone-shaped material pile model.

4. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 2, characterized in that, The second material pile model is a long strip-shaped material pile model.

5. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 2, characterized in that, Store the first and second stockpile sub-models as a sub-model library.

6. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 1, characterized in that, If there are multiple unloading ports in the actual site, after constructing the unloading model, the unloading model is arranged into a rectangular array according to the spacing between the unloading ports in the actual site, and the intersection of the unloading model set obtained by the rectangular array and the natural stockpile model is calculated.

7. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 1, characterized in that, The length, width, and planar coordinates of the discharge port are parameterized respectively.

8. The method for determining the effective volume of a bulk material pile based on three-dimensional parametric modeling according to claim 1, characterized in that, When the outline of the discharge port is located within the orthographic projection outline of the natural accumulation pile model, the discharge model is obtained by drawing all sides of the stretching feature.

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