阅读说明：本技术 一种基于点云测量技术的工程土方计量方法 (Engineering earthwork measuring method based on point cloud measuring technology ) 是由 殷达 汪望明 许向东 张鹏 廖曾平 于 2020-05-15 设计创作，主要内容包括：本发明的一种基于点云测量技术的工程土方计量方法,采用微积分思想,在操作快速方便的基础上,显著提高了计算精度和计算效率,具有较强的鲁棒性,适用于各类常见土方工程场景,其计算精度取决于输入的三维地形数据本身的质量,该方法可实现高度自动化,只需输入设计数字三维曲面、水下测量数据和投影点阵排布参数,显著减少了人工操作,特别的,该方法涉及点云处理,可与激光扫描技术、无人机摄影技术等新技术兼容耦合,具备良好扩展性。(The engineering earthwork metering method based on the point cloud measurement technology adopts the calculus idea, obviously improves the calculation precision and the calculation efficiency on the basis of quick and convenient operation, has stronger robustness, is suitable for various common earthwork engineering scenes, and the calculation precision depends on the quality of input three-dimensional topographic data.)

1. A project earthwork measuring method based on a point cloud measuring technology is characterized by comprising the following steps:

s1, based on the target three-dimensional terrain curved surface data, the initial three-dimensional terrain curved surface data and the stage three-dimensional terrain curved surface data, obtaining construction point clouds of the target terrain curved surface, the initial three-dimensional terrain curved surface and the stage three-dimensional terrain curved surface by a three-dimensional curved surface interpolation method;

s2, respectively carrying out differential processing on the horizontal projection of the constructed point cloud by adopting a triangular grid or a Thiessen polygonal grid to obtain a projection lattice constructed grid;

s3, calculating the difference of the infinitesimal volume of the grid column body to judge whether the excavation or filling is carried out;

and S4, respectively accumulating and summing the volume values obtained by differentiating the prismatic micro-elements formed by dividing the grid according to the positive and negative values to obtain the engineering earthwork amount.

2. The method for engineering earthwork measurement based on point cloud measurement technology as claimed in claim 1, wherein the step S2 is detailed by the following steps:

s21, projecting the constructed point cloud of the target terrain curved surface, the constructed point cloud of the initial three-dimensional terrain curved surface and the constructed point cloud of the stage three-dimensional terrain curved surface respectively to obtain a projected dot matrix of the constructed point cloud of the target terrain curved surface on a horizontal plane, a projected dot matrix of the constructed point cloud of the initial three-dimensional terrain curved surface on the horizontal plane and a projected dot matrix of the constructed point cloud of the stage three-dimensional terrain curved surface on the horizontal plane;

and S22, performing differential processing on the triangular grid or the Thiessen polygonal grid to obtain a projection lattice construction grid.

3. The engineering earthwork measurement method based on the point cloud measurement technology as claimed in claim 2, wherein the differential processing of the triangular mesh is adopted in S22 by constructing the triangular mesh with the minimum ternary lattice of the construction point cloud of the target topographic curved surface in the horizontal plane projection lattice as the vertex, and sequentially connecting all the points in the lattice to form the projection lattice construction mesh of the target topographic curved surface; constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the initial three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form a projection lattice construction grid of the initial three-dimensional terrain curved surface; and constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the stage three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form the projection lattice construction mesh of the stage three-dimensional terrain curved surface.

4. The engineering earthwork measuring method based on the point cloud measuring technology as claimed in claim 2, wherein: the method for differential processing by adopting the Thiessen polygonal grid in the S22 comprises the steps of taking a projection lattice of the structural point cloud of the target terrain curved surface on a horizontal plane as input data, and subdividing a projection plane of a calculation area by adopting a Voronoi function to form a projection lattice structural grid of the target terrain curved surface; taking a projection lattice of the structural point cloud of the initial three-dimensional terrain curved surface on a horizontal plane as input data, and subdividing a projection plane of a calculation area by adopting a Voronoi function to form a projection lattice structural grid of the initial three-dimensional terrain curved surface; and constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the stage three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form the projection lattice construction mesh of the stage three-dimensional terrain curved surface.

5. The method for engineering earthwork measurement based on the point cloud measurement technique as claimed in claim 3, wherein the step S3 comprises the following steps:

subtracting the projection lattice construction grid infinitesimal of the three-dimensional terrain curved surface of the stage from the projection lattice construction grid infinitesimal of the initial three-dimensional terrain curved surface, and when the difference value is greater than zero, determining as an excavation; when the difference value is less than zero, filling is carried out.

6. The method for engineering earthwork measurement based on the point cloud measurement technology as claimed in claim 4, wherein the step S3 comprises the following steps:

subtracting the projection lattice construction grid of the target terrain curved surface from the projection lattice construction grid infinitesimal of the stage three-dimensional terrain curved surface, and taking the construction grid as an excavating party when the difference value is greater than an allowable underexcavating value; and when the difference value is larger than the allowable overbreak value, filling.

7. The method as claimed in claim 1, wherein the target three-dimensional terrain and curved surface data is a design digital three-dimensional curved surface model of an engineering project based on BIM technology, and control points on curved surface control lines are extracted by programming means to form point cloud data.

8. The method as claimed in claim 1, wherein the initial three-dimensional topographic curved surface data is obtained by collecting topographic surface data by point cloud measurement before entering construction, calibrating and correcting the data to form initial topographic point cloud data.

9. The method as claimed in claim 1, wherein the step three-dimensional topographic curved surface data is obtained by performing topographic surface data collection by using a point cloud measuring technique, calibrating and correcting the data to form step topographic point cloud data when step measurement is required in a construction cycle.

Technical Field

The invention relates to the technical field of earth volume calculation methods, in particular to an engineering earth volume metering method based on a point cloud measurement technology.

Background

In the civil engineering field, earthwork measurement is taken as an important basis for construction and settlement, and the whole construction period is run through. Classical earth volume calculation methods include a fracture plane method, a square grid method, and an irregular triangular grid method.

The section method is commonly used for earthwork calculation of long and narrow areas such as roads, river banks and the like. A plurality of typical engineering sections are selected based on the engineering design data, and uniform variation between adjacent sections is assumed. The method is essentially a simplified model and is only suitable for simple construction situations. When the terrain is complex, a large error exists between the calculation result and the actual earth volume.

The square grid method is commonly used for earthwork calculation of a field with small topographic relief and gentle slope change. The field is divided into a plurality of square grids, and then the volume of each quadrangular prism is calculated, so that the volumes of all quadrangular prisms are gathered to obtain the total earth volume. The area of the coverage area of the square grid divided by the method is large, so that the requirement on site terrain is severe. Meanwhile, the method is very complicated in calculation processing of the geometric boundary of the special-shaped area.

Irregular triangular meshes (TINs) are one of the manifestations of Digital Terrestrial Models (DTMs). The method utilizes actually measured topographic feature points to construct a triangular grid, and earthwork is calculated for a calculation area according to a triangular prism method. The calculation precision and efficiency of the method depend on the mesh subdivision quality of the irregular triangular mesh, and the method has high requirements on engineering technicians.

On the other hand, conventional technologies such as a level gauge, a total station, a GPS-RTK measurement and the like are commonly adopted for the earthwork survey. With the improvement of computer computing power and the development of intelligent algorithms, emerging technologies such as multi-beam measurement, laser scanning measurement, unmanned aerial vehicle photogrammetry and the like are increasingly applied to the field of civil engineering in recent years. Unlike conventional techniques, this type of emerging technology is based on point cloud measurement data sets. The traditional earthwork measuring method does not consider the input of the point cloud data set at the beginning of design, can not effectively and fully utilize the input data, and is not beneficial to actual production and construction.

Disclosure of Invention

The invention provides an engineering earthwork measuring method based on a point cloud measuring technology, which aims to solve the technical problems of large error, poor robustness and large amount of manual intervention of the existing earthwork measuring method.

According to one aspect of the invention, the engineering earthwork measuring method based on the point cloud measuring technology comprises the following steps:

s1, based on the target three-dimensional terrain curved surface data, the initial three-dimensional terrain curved surface data and the stage three-dimensional terrain curved surface data, obtaining construction point clouds of the target terrain curved surface, the initial three-dimensional terrain curved surface and the stage three-dimensional terrain curved surface by a three-dimensional curved surface interpolation method;

s2, respectively carrying out differential processing on the horizontal projection of the constructed point cloud by adopting a triangular grid or a Thiessen polygonal grid to obtain a projection lattice constructed grid;

s3, calculating the difference of the infinitesimal volume of the grid column body to judge whether the excavation or filling is carried out;

and S4, respectively accumulating and summing the volume values obtained by differentiating the prismatic micro-elements formed by dividing the grid according to the positive and negative values to obtain the engineering earthwork amount.

On the basis of the above scheme, preferably, the detailed step of step S2 is:

s21, projecting the constructed point cloud of the target terrain curved surface, the constructed point cloud of the initial three-dimensional terrain curved surface and the constructed point cloud of the stage three-dimensional terrain curved surface respectively to obtain a projected dot matrix of the constructed point cloud of the target terrain curved surface on a horizontal plane, a projected dot matrix of the constructed point cloud of the initial three-dimensional terrain curved surface on the horizontal plane and a projected dot matrix of the constructed point cloud of the stage three-dimensional terrain curved surface on the horizontal plane;

and S22, performing differential processing on the triangular grid or the Thiessen polygonal grid to obtain a projection lattice construction grid.

Preferably, based on the above scheme, the specific method of differential processing of the triangular mesh in S22 is to construct the triangular mesh by using the minimum ternary lattice of the construction point cloud of the target terrain curved surface in the horizontal plane projection lattice as the vertex, and sequentially connect all points in the lattice to form the projection lattice construction mesh of the target terrain curved surface; constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the initial three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form a projection lattice construction grid of the initial three-dimensional terrain curved surface; and constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the stage three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form the projection lattice construction mesh of the stage three-dimensional terrain curved surface.

Preferably, based on the above scheme, in S22, the method for performing differential processing on the thiessen polygon mesh is to use the projection lattice of the structural point cloud of the target terrain curved surface on the horizontal plane as input data, and subdivide the projection plane of the calculation area by using Voronoi function to form the projection lattice structural mesh of the target terrain curved surface; taking a projection lattice of the structural point cloud of the initial three-dimensional terrain curved surface on a horizontal plane as input data, and subdividing a projection plane of a calculation area by adopting a Voronoi function to form a projection lattice structural grid of the initial three-dimensional terrain curved surface; and constructing a triangular mesh by taking the minimum ternary lattice of the constructed point cloud of the stage three-dimensional terrain curved surface in the horizontal plane projection lattice as a vertex, and sequentially connecting all points in the lattice to form the projection lattice construction mesh of the stage three-dimensional terrain curved surface.

On the basis of the above scheme, preferably, the step S3 specifically includes:

subtracting the projection lattice construction grid infinitesimal of the three-dimensional terrain curved surface of the stage from the projection lattice construction grid infinitesimal of the initial three-dimensional terrain curved surface, and when the difference value is greater than zero, determining as an excavation; when the difference value is less than zero, filling is carried out.

On the basis of the above scheme, preferably, the step S3 specifically includes:

subtracting the projection lattice construction grid of the target terrain curved surface from the projection lattice construction grid infinitesimal of the stage three-dimensional terrain curved surface, and when the value is greater than the allowable underexcavation value, taking the construction grid as an excavation party; and when the value is larger than the allowable overbreak value, filling.

On the basis of the scheme, the target three-dimensional terrain curved surface data is preferably a design digital three-dimensional curved surface model of an engineering project constructed based on a BIM technology according to design data, and control points on a curved surface control line are extracted by adopting a programming means to form point cloud data.

On the basis of the scheme, the initial three-dimensional terrain curved surface data is preferably acquired by adopting a point cloud measurement technology before entering construction, and the initial terrain point cloud data is formed after the data is calibrated and corrected.

On the basis of the scheme, preferably, the stage three-dimensional terrain curved surface data is stage terrain surface data acquisition work by adopting a point cloud measurement technology when stage measurement is required in a construction period, and the stage terrain surface point cloud data is formed after the data is calibrated and corrected.

The engineering earthwork metering method based on the point cloud measurement technology adopts the calculus idea, obviously improves the calculation precision and the calculation efficiency on the basis of quick and convenient operation, has stronger robustness, is suitable for various common earthwork engineering scenes, and the calculation precision depends on the quality of input three-dimensional topographic data.

Drawings

FIG. 1 is a schematic flow chart of an engineering earthwork measurement method based on a point cloud measurement technology according to the present invention;

FIG. 2a is a schematic diagram of an unprocessed point cloud according to an embodiment of the present invention;

FIG. 2b is a schematic diagram of an unprocessed point cloud according to an embodiment of the present invention;

FIG. 3a is a schematic diagram of constructing a point cloud according to one embodiment of the present invention;

FIG. 3b is a schematic diagram of an unprocessed point cloud according to an embodiment of the present invention;

FIG. 4a is a schematic diagram of a triangular mesh according to an embodiment of the present invention

FIG. 4b is a schematic diagram of a triangular mesh according to an embodiment of the present invention

Fig. 4c is a schematic diagram of a triangular mesh according to an embodiment of the present invention;

FIG. 5 is a schematic diagram illustrating the calculation of the excavation volume of the prism under the triangular grid according to the embodiment of the present invention;

FIG. 6a is a schematic diagram of a Thiessen polygonal mesh according to an embodiment of the present invention;

FIG. 6b is a schematic diagram of a Thiessen polygonal mesh according to an embodiment of the present invention;

fig. 6c is a schematic diagram of a thiessen polygonal mesh according to an embodiment of the present invention;

FIG. 7 is a schematic diagram illustrating calculation of the super-undermining height and volume of the prism under the Thiessen polygonal grid according to the embodiment of the present invention;

FIG. 8a is a schematic diagram of an unprocessed point cloud according to a second embodiment of the present invention;

FIG. 8b is a schematic diagram of an unprocessed point cloud according to a second embodiment of the present invention;

FIG. 9a is a schematic diagram of constructing a point cloud according to a second embodiment of the present invention

FIG. 9b is a schematic diagram of constructing a point cloud according to a second embodiment of the present invention;

fig. 10 is a schematic diagram of a triangular mesh according to a second embodiment of the present invention;

fig. 11 is a schematic view of a thiessen polygonal mesh according to a second embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.