Underground pipeline construction path planning optimization analysis method

Abstract

The invention discloses an underground pipeline construction path planning optimization analysis method, and particularly relates to the field of pipeline construction planning, and the method comprises the steps: collecting elevation grid data covering a construction region, and generating a node-level continuous slope direction sequence in combination with a replied path initial line; recognizing a continuous one-way slope section in the path, and delimiting a one-way high-voltage path section with continuously accumulated height difference as a structure optimization target; aiming at the path segments, constructing a feasible structure compression candidate segment set in a transverse adjacent space of the path segments; slope fluctuation and break angle distribution conjoint analysis is carried out on the candidate segments, structural complexity features are extracted, and a two-dimensional compression matrix is constructed; constructing a structure empowerment connection graph based on the matrix, executing minimum empowerment path search in combination with structure continuity constraint, and screening out an optimal alternative path segment structure; and finally, the head and tail nodes of the original path section are used as anchor points, the alternative path section is inserted into the original path initial line, and construction path planning after structure optimization is formed.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline construction planning, and more specifically, to an optimization analysis method for the construction path planning of underground pipelines. Background Art

[0002] In the high-relief terrain environment widely distributed in the transition area between hills, mountains and tablelands, the construction of underground pipelines faces complex terrain adaptability challenges. Limited by the terrain slope direction and geomorphic trend, the path layout often needs to extend along with the natural undulation of the mountain body. Especially in areas lacking long-distance tunneling or overhead conditions, the pipelines need to be continuously laid along the surface trend. However, in these complex terrains, there often appear path segments with continuous long-distance single slope directions, that is, the path continuously rises or falls within a relatively long distance. Such path structures are prone to cause the problem of cumulative one-way elevation load during the construction process, manifested as the excavation operation continuously deepening or shallowing in a certain direction, resulting in a geometric amplification of the construction burden in the latter section of the path. Specifically, when the path segment continuously climbs, the vertical height difference between the starting point and the ending point along the line continuously increases, and finally a deep foundation pit dozens of meters deep may be formed, bringing a series of technical problems such as slope stability control, boundary support and collapse prevention. On the contrary, if the path segment continuously cuts down, it is necessary to face a large amount of backfilling and stepped support treatment, and at the same time, it may also cause geological and hydrological problems such as rainwater backflow and low-lying water accumulation.

[0003] In the above two situations, the traditional path segment design method is difficult to identify and adjust the local height difference overload segment, resulting in a non-linear growth trend of blasting volume, transportation volume and support engineering, seriously affecting the overall construction organization efficiency and the stability of resource allocation. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides an optimization analysis method for the construction path planning of underground pipelines to solve the problems proposed in the above background art.

[0005] To achieve the above object, the present invention provides the following technical solutions: An optimization analysis method for the construction path planning of underground pipelines, comprising the following steps: S1: Collect the elevation grid data within the pipeline layout range of the target mountain, and generate a path continuous slope direction sequence based on the initially approved construction path; S2: Identify the one-way slope segments in the path continuous slope direction sequence, and delimit the one-way high-pressure path segments; S3: Based on the starting and ending boundary points of the one-way high-pressure path segments, search for the set of candidate segments for the lateral alternative structure compression in the laterally adjacent space; S4: Perform slope fluctuation and fold angle distribution analysis on all sets of candidate structure compression segments, and construct a two-dimensional compression matrix for the alternative structure of the one-way height difference burden path segments; S5: Based on the alternative structure two-dimensional compression matrix, construct a structure-weighted connection graph, perform continuous path minimum-weight search and splice nodes to establish an alternative construction path; S6: Merge the alternative construction path into the initial construction path line through the method of replacing the same nodes to generate an optimized construction path plan.

[0006] In a preferred embodiment, in S1, collecting elevation grid data within the layout range of the target mountain pipeline, and generating a path continuous slope direction sequence based on the approved initial construction path line specifically includes: Within the mountain target pipeline layout area, perform sampling dot matrix generation on the elevation surveying data to construct an elevation dot matrix space corresponding to the terrain undulation, and the dot matrix space is represented in the form of grid data; Generate equally spaced nodes along the linear direction of the approved initial construction path line to form a set of path node sequences with position indexes; Based on the set of path node sequences, construct a spatial polyline vector structure of the initial construction path line, and map it to the elevation dot matrix space. Calculate the elevation difference between adjacent path nodes within the elevation dot matrix space, and generate a path continuous slope direction sequence based on the calculation results.

[0007] In a preferred embodiment, in S2, identifying one-way slope segments in the path continuous slope direction sequence and demarcating one-way high-pressure path segments specifically includes: Based on the elevation differences between path nodes in the path continuous slope direction sequence, identify structural paragraphs with continuously monotonous changes in slope direction trends, and integrate the corresponding structural paragraphs into a set of one-way slope segments based on the slope direction trends; Perform equally long sliding window segmentation within the set of one-way slope segments to construct a group of sub-intervals with a fixed node span; Continuously superimpose the elevation differences between path nodes within each sub-interval of the sub-interval group, identify the sections where the cumulative height difference exceeds the set threshold, and label the corresponding sections as one-way height difference burden path segments.

[0008] In a preferred embodiment, in S3, based on the start and end boundary points of the one-way high-pressure path segment, search for a set of candidate segments for lateral alternative structure compression in the laterally adjacent space specifically includes: Extract the start and end node positions of the one-way height difference burden path segment, and construct a lateral space offset band structure with the paragraph trend as the baseline; According to the preset construction path direction angle threshold and the maximum elevation difference threshold limit, demarcate a path offset search space in the lateral space offset band structure, and select several alternative path nodes according to the construction condition constraints; Based on alternative path nodes, generate a set of connectable paths between the start and end nodes within the path offset search space, and record the high-level sequence of path nodes corresponding to each path segment; Perform elevation difference positive / negative sign extraction and turning point marking on the high-level sequences of each path segment in the set of connectable paths, and classify the path node sequences with slope direction turning structures into the set of structure compression candidate segments.

[0009] In a preferred embodiment, in S4, performing slope fluctuation and fold angle distribution analysis on all sets of structure compression candidate segments, and constructing a two-dimensional compression matrix for the alternative structure of one-way height difference burden path segments specifically includes: In the path node sequence of the set of structure compression candidate segments, sequentially extract the elevation difference and horizontal distance between adjacent nodes to generate a sequence of slope values between nodes; Perform first-order difference processing on the sequence of slope values between nodes, and construct a fluctuation feature expressing the degree of slope fluctuation based on the difference processing results; Map the path node sequence of the structure compression candidate segment to a set of line segment vectors, and establish a fold angle distribution sequence based on the included angle between adjacent vectors, and construct a fold angle variation feature according to the fold angle distribution sequence; Perform feature combination on the slope fluctuation features and fold angle variation features of all compression candidate segments, map the combined features to the path start and end node indexes corresponding to the one-way height difference burden path segments, and construct a two-dimensional compression matrix for the alternative structure.

[0010] In a preferred embodiment, the method of establishing a fold angle distribution sequence based on the included angle between adjacent vectors and constructing a fold angle variation feature according to the fold angle distribution sequence is to calculate the cosine complement of all fold angles in the fold angle distribution sequence, and use the average value of the cosine complements as the fold angle variation feature of the corresponding structure compression candidate segment.

[0011] In a preferred embodiment, in S5, constructing a structure weighted connection graph based on the two-dimensional compression matrix of the alternative structure, performing continuous path minimum weighted search and splicing nodes to establish an alternative construction path specifically includes: Based on the two-dimensional compression matrix of the alternative structure of one-way height difference burden path segments, construct a structure weighted connection graph with connected nodes, and map the corresponding structure compression candidate segments in the two-dimensional compression matrix to the set of valid edge indexes in the structure weighted connection graph; Among them, the weight of the valid edge of the structure weighted connection graph is obtained by weighted operation of the fluctuation feature, fold angle variation feature and path length of the compression candidate segment; In the structure weighted connection graph, with the start and end node order of each structure compression candidate segment as the path search constraint, perform minimum weighted path search under the constraint of structure continuity; Sequentially splice the path nodes of each structural compression candidate segment in the obtained minimum weighted path into a continuous path segment as the alternative construction path.

[0012] In a preferred embodiment, in S6, incorporating the alternative construction path into the initial construction path line by the method of replacing the same nodes specifically involves extracting the node indices of the starting point and the ending point of the alternative path segment in the initial construction path line structure, performing a structure deletion operation on the original path node sequence within the replacement index range, and sequentially inserting the middle node sequence of the alternative path segment into this range.

[0013] The technical effects and advantages of an underground pipeline construction path planning and optimization analysis method of the present invention: By collecting elevation grid data to generate a continuous slope aspect sequence, it can effectively identify the unidirectional high-pressure path segments in the construction path caused by the accumulation of slope aspects, and expose in advance the potential risks of structural burdens such as deep foundation pits and high-pressure backfills. Further, construct a set of structural compression candidate segments in the lateral adjacent space of the path segment, and through the analysis of slope fluctuations and fold angle distributions, accurately construct a two-dimensional compression matrix of alternative structures, providing a quality ranking basis for the structural replacement of the path segment. The solution introduces a structural weighted connection graph mechanism when searching for alternative paths, supports the minimum weighted search of continuous paths, and avoids the path breakage problem caused by the isolated selection of traditional candidate segments. Finally, through the method of replacing the same node mapping, seamless fusion of the path structure is realized, ensuring that the overall trend and spatial connectivity of the original path are maintained. This solution has multiple advantages such as pre-identifying construction burdens, strong continuity of alternative structural paths, and the resulting path can be directly used for the correction of construction drawings. Brief Description of the Drawings

[0014] Figure 1 It is a schematic diagram of an underground pipeline construction path planning and optimization analysis method of the present invention. Detailed Embodiment

[0015] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0016] Embodiment 1 Figure 1 An underground pipeline construction path planning and optimization analysis method of the present invention is given, which includes the following steps: S1: Collect elevation grid data within the pipeline layout range of the target mountain area, and generate a path continuous slope aspect sequence based on the approved initial construction path line; S2: Identify the unidirectional slope segments in the continuous slope direction sequence of the path, and delimit the unidirectional high-pressure path segments; S3: Based on the start and end boundary points of the unidirectional high-pressure path segments, search for the set of candidate segments for lateral alternative structure compression in the laterally adjacent space; S4: Perform slope fluctuation and fold angle distribution analysis on all sets of candidate segments for structure compression, and construct a two-dimensional compression matrix for the alternative structures of the unidirectional height difference burden path segments; S5: Construct a structure-weighted connection graph based on the two-dimensional compression matrix of the alternative structures, perform a continuous path minimum-weight search and splice the nodes to establish an alternative construction path; S6: Incorporate the alternative construction path into the initial construction path by means of replacing the same nodes, and generate an optimized construction path plan.

[0017] In S1, collect the elevation grid data within the layout range of the target mountain pipeline, and generate a continuous slope direction sequence of the path based on the approved initial construction path.

[0018] Obtain the basic topographic survey data within the target mountain area. The data source can be the completed topographic map, remote sensing image, or DEM (Digital Elevation Model) data collected by means of UAV aerial survey, lidar, etc. The selected data should meet the requirement that the spatial resolution is not less than 5 meters to ensure sufficient topographic relief expression ability in the area with large mountain height differences. The generation process of the sampling lattice points can adopt the regular grid method, that is, evenly divide the entire area at a fixed interval on the two-dimensional plane. For example, set the grid size to 10 meters × 10 meters to form a rectangular lattice covering the entire target area. Each grid unit corresponds to a unique position, and this position contains an elevation value, which can be directly extracted from the original elevation survey data. If the original data is in the form of irregular point cloud, the elevation value filling can be completed through interpolation algorithms (such as inverse distance weighted interpolation or bilinear interpolation). The final generated elevation lattice space can be saved in standard formats such as GeoTIFF, ASC, or Grid for subsequent spatial analysis.

[0019] The initially approved construction path is regarded as a continuous polyline structure with a spatial orientation, and the polyline data in CAD or GIS format is provided by the design unit. To perform spatial structure analysis and elevation difference calculation, the initial path is discretized into a set of nodes with spatial distribution rules. The spatial coordinate data of the initial path is read, and its complete orientation path is extracted. Subsequently, according to the equipment control accuracy and terrain response scale in the actual pipeline construction plan, the generation interval between path nodes is set. Taking the main water supply pipeline or cable trench in mountainous areas as an example, it is recommended that the generation interval can be set between 1 meter and 5 meters. Among them, a 1-meter node density is applicable to the rock slope section with frequent elevation fluctuations, and 5 meters is applicable to relatively flat sections. Once the node interval is set, equidistant discretization is performed along the entire path in the direction from the starting point to the ending point, and multiple path nodes are generated in sequence. Each node has a unique spatial coordinate (X, Y) and a numbered index, forming a set of path node sequences. In addition, to ensure that there are no sampling errors caused by path curvature or turning points during the node generation process, a segment interpolation algorithm based on line segment length can be used. This algorithm judges the length of each polyline segment and distributes the number of nodes proportionally, ensuring that even at the path turning points, a node sequence that precisely matches the curve shape can be generated. All nodes will be numbered in a linear structure and accompanied by the start and end identifiers of the line segment where they are located, facilitating subsequent slope calculation and spatial reconstruction operations. The node sequence is finally stored in an engineering processing format, including information such as node numbers, horizontal and vertical coordinates, and line segment numbers.

[0020] Using the generated path node sequence as the basic data, construct the vector structure of the initial path in space. The spatial polyline vector structure refers to a set of line segments formed by sequentially connecting adjacent path nodes according to their numbers. Each pair of consecutive nodes forms a spatial vector with a direction and a length. These vector sets describe the orientation of the path in the plane space and provide the node correspondence for the elevation difference analysis. Then, perform the mapping operation of the path nodes in the elevation grid space. Each path node is located in the corresponding cell of the elevation grid according to its horizontal and vertical coordinates. To obtain the row and column indices by rounding down the node coordinates, or perform bilinear interpolation in the four-neighborhood to obtain a more accurate elevation value. After the mapping is completed, assign the elevation values in the elevation grid to each path node to generate a node sequence with three-dimensional information (X, Y, H). Then, calculate the elevation difference between each pair of adjacent nodes, that is, subtract the elevation of the previous node from the elevation of the next node to obtain the elevation difference sequence between the path nodes. This sequence reflects the continuous trend of the path climbing or descending in space. To express this trend, each elevation difference can be mapped to a direction value (e.g., +1 for rising, -1 for falling, 0 for flat), and a continuous slope direction sequence of the path is constructed. The finally formed path slope direction sequence is an important structural description of the path height difference change, which can be used to identify continuous uphill sections, continuous downhill sections, and slope direction turning points in subsequent analysis, and is the key basis for realizing the identification of one-way height difference burden path segments. This sequence can be stored as a one-dimensional structure, accompanied by the starting and ending node numbers corresponding to each segment, which is convenient for direct calling in modules such as structure compression and alternative path search.

[0021] In S2, identify the one-way slope segments in the continuous slope direction sequence of the path and delimit the one-way high-pressure path segments.

[0022] Based on the path node sequence, calculate the elevation differences between adjacent path nodes in turn. Each pair of adjacent nodes forms a path segment unit, and the elevation difference of this unit is obtained by subtracting the elevation of the starting node from the elevation of the ending node. The positive and negative of the elevation difference correspond to the rising or falling direction of the path segment respectively, forming the continuous slope direction sequence of the path. This sequence is the basic basis for identifying the trend of path slope change. To identify the structural paragraphs with continuously consistent directions in the path, perform monotonicity detection in the path slope direction sequence. The starting node is used as the starting point of the first structural segment, and then sequentially search for path segments with consistent directions in the subsequent nodes, and classify these path segments with the same continuous direction into the same trend segment. If the first elevation difference opposite to the current trend direction appears in the sequence, it is determined that this trend segment ends. Then, start identifying the next trend segment from this node and repeat this process until the entire path sequence is processed. Each structural paragraph records its starting and ending node numbers, the direction attribute within the segment (continuous rising or continuous falling), and the number of nodes included.

[0023] In the actual process, to avoid trend interruptions caused by short-distance terrain fluctuations or measurement errors, a minimum trend segment length threshold is set for the identification of direction changes. For example, if the path node spacing is 2 meters, 10 meters can be set as the minimum continuous trend segment length, that is, a same-direction slope segment containing at least 5 consecutive nodes is regarded as a valid trend segment. Direction changes shorter than this length are not divided into new segments, but merged into the previous trend segment. Multiple structural segments with the same direction are integrated to construct a set of one-way slope segments. The integration operation starts from the first segment of the path structure paragraph set and judges its direction attribute paragraph by paragraph. If the current structural segment has the same direction as the previous one (for example, both are uphill or both are downhill), it can be merged into the previous one-way slope segment. The starting node number before the merge is retained for the new slope segment after the merge, and the ending node number is updated to the ending node of the current paragraph. This process is executed sequentially until a structural segment with a changed direction attribute is encountered. At this time, the current one-way slope segment structure is closed, the starting and ending node numbers and direction attributes of this segment are saved, and a new slope segment construction process is started. The final result is integrated into a set of one-way slope segments.

[0024] After obtaining the set of one-way slope segments, to identify local elevation difference aggregation sections in the elevation difference change trend of the path at the micro scale, an equal-length segmentation operation is performed inside each one-way slope segment. The segmentation process uses a sliding window method to divide each one-way slope segment into several sub-intervals of the same length. The sliding window is set based on the number of nodes rather than the actual distance length. Taking the path node spacing of 2 meters as an example, if the analysis hopes to cover the elevation difference trend change within 20 meters, the window size can be set to 10 nodes. The window sliding step size can be set to 50% of the window size or less, that is, there can be an overlapping area between windows to increase the coverage density and analysis resolution of the sub-intervals. The segmentation process starts from the starting node of the one-way slope segment and slides forward one step unit each time to generate a new sub-interval. Each sub-interval records information such as its starting and ending node numbers, the node list within the window, and the one-way slope segment number it belongs to. If in the last sliding stage, the remaining number of nodes is less than the length of a complete window, it can be chosen not to generate a new sub-interval, or to allow the last window to shorten the node span while maintaining the direction consistency. All window segmentations are performed inside their respective one-way slope segments without crossing the slope direction boundary to ensure that each sub-interval maintains the same direction attribute.

[0025] Process each subset of intervals within the sliding window one by one, and calculate the cumulative value of the continuous elevation differences between the internal path nodes. In each subset of intervals, starting from the starting node, successively add up the elevation differences of all adjacent path segments. Only the elevation differences consistent with the direction of this subset of intervals are included in the addition process. If there are elevation differences in the opposite direction, this segment can be ignored or treated as zero to reduce the disturbing influence caused by fluctuations. After the accumulation is completed, compare the cumulative elevation difference of each subset of intervals with a preset threshold. The threshold setting can be determined according to engineering construction conditions, equipment capabilities, or path design specifications. For example, in the mountainous section where the water supply pipeline is laid by the trenching method, if the cumulative elevation difference exceeds 5.5 meters in a 20-meter-long path, step excavation, mechanical assisted pushing, or slope support needs to be implemented. At this time, the elevation difference burden judgment threshold can be set at 5.5 meters. If the pipeline construction uses blasting or tunneling techniques, this threshold can be relaxed to 8 meters or 10 meters, and the specific value should be determined by the construction restriction requirements. When the cumulative elevation difference of a subset of intervals exceeds the threshold, mark this subset of intervals as an elevation difference burden section. If multiple adjacent subsets of intervals continuously meet the conditions, paragraph merging can be performed to generate a longer elevation difference burden path segment. Each elevation difference burden path segment records the start and end node numbers, the cumulative elevation difference value, the one-way slope section it belongs to, and the index range of the subset of intervals, which is convenient for the structure compression, construction optimization, and alternative path planning modules to call.

[0026] In S3, based on the start and end boundary points of the one-way high-pressure path segment, search for the set of candidate segments for lateral alternative structure compression in the laterally adjacent space.

[0027] Extract the node numbers and corresponding two-dimensional coordinates of the start and end points of the identified one-way elevation difference burden path segment. After extracting the start and end nodes, calculate the spatial trend vector of this path segment. The spatial trend is defined as the direction of the line connecting the start point to the end point, representing the geometric direction of this path segment in the two-dimensional coordinate plane, which is used as the reference direction for constructing the lateral offset zone. On this basis, construct the left and right offset directions orthogonal to the trend of the path segment, that is, generate a lateral projection reference perpendicular to the main axis of the path segment, which is used to define the range of the lateral search zone. Based on this orthogonal direction, construct several equally spaced lateral strip-shaped regions on the left and right sides of the path segment respectively. Each region takes the main axis of the path segment as the center line and expands to both sides by a preset lateral expansion distance to form a set of two-dimensional regions in the shape of a rectangle or strip. The setting of the lateral expansion distance should comprehensively consider factors such as the possible bypass space for pipeline laying, the constructability of the terrain, and the occupied space resources. For example, in areas where manual slope cutting or mechanical excavation is allowed by the terrain, the lateral offset zone can be set at 15 meters on both sides of the original path; while in areas with complex terrain or dense existing structures, it can be reduced to 5 meters on both sides to avoid destructive construction. Finally, this lateral spatial offset zone structure is bounded by the start and end points of the path segment, distributed in a strip shape, and takes the trend of the path segment as the main axis direction.

[0028] Based on the constructed lateral space offset band structure, a series of constraint rules are set to screen the path nodes within the offset band, so as to delimit the effective search space for path offset and generate a set of candidate nodes for constructing alternative paths. First, a number of space points are sampled at a fixed interval within the lateral offset band, and it is judged whether these sampled points meet the basic geometric conditions for the connectivity of the engineering path.

[0029] Among them, the first restriction is the path direction angle restriction. For each potential alternative path node, it is required to simultaneously satisfy that the angle formed by the connection line with the starting point or the ending point of the original path segment does not exceed the set threshold. The setting of the direction angle is used to avoid large-angle turning back or sudden direction change of the alternative path. In actual engineering, the direction angle threshold is often set within 45°. When the angle between the connection line of the sampled point and the starting point or the ending point and the direction of the original path exceeds this threshold, it is considered that the direction of this point deviates too much and does not have the direction continuity of forming a path segment, and it is excluded.

[0030] The second restriction is the elevation difference restriction. For each sampled point, calculate the elevation difference between its elevation value and the elevation of the starting point or the ending point of the original path segment. If this difference exceeds the preset maximum elevation difference threshold, it is considered that there may be a sudden change in the terrain at this point, and the construction difficulty of slope cutting, foundation pit deep excavation or high fill operation required is too high, so it is not included in the candidate range. For the construction path of open foundation, this elevation difference threshold usually does not exceed 6 meters; for tunnel or underground excavation path, it can be relaxed to about 10 meters. On the basis of simultaneously meeting the two constraint conditions, the point selection also needs to be screened in combination with the construction process conditions. For example, if the path laying needs to avoid restrictive features such as high-voltage lines, building boundaries or river channels, then on the basis of elevation and direction restrictions, the obstacle raster layer is further called to judge the spatial occlusion of the candidate points, and the nodes with overlapping or intersecting relationships with the obstacles are excluded. The set of candidate path nodes after screening constitutes the effective node set in the path offset search space.

[0031] Using the selected alternative path nodes as the basic data, perform path reconstruction operations within the path offset search space. The operation objective is to generate a path segment leading to the end node from the start node along a structurally continuous and elevation-varying acceptable path without violating the principles of path directionality and connectivity, and record the nodes included in the path segment and their corresponding elevations. In the set of alternative nodes, determine the connectable boundaries between nodes by constructing an adjacency relationship index. The judgment criteria for whether two nodes are connectable are mainly set based on spatial distance, slope difference, and direction continuity. For example, when the spatial distance between adjacent nodes does not exceed 10 meters, the slope does not exceed 12%, and the included angle between the connection direction and the overall path segment trend is less than 60°, it can be considered that the two nodes are passable. All eligible connection relationships are organized in a graph structure to form an "alternative node connectivity graph". Based on the connectivity graph structure, use a path search algorithm (such as breadth-first search or A* search) to generate the set of all reachable paths from the start node to the end node. To control the number and length of candidate paths, the maximum search depth can be limited or the path length upper limit can be set, such as not exceeding 1.5 times the length of the original path segment. For each generated path segment, record its constituent node sequence, and retrieve the corresponding elevation values of each node in the elevation dot matrix space in the node sequence to form a complete path segment elevation sequence.

[0032] After obtaining the set of connectable paths and their corresponding path elevation sequences, perform direction continuity analysis on each path segment. This analysis process aims to identify the positions with obvious slope direction changes in the path structure and judge whether they constitute candidate segments for executable structure compression operations based on the turning characteristics. The specific operation is as follows: Calculate the elevation difference between adjacent nodes for the elevation sequence of each path segment, and extract the positive and negative sign sequence of the elevation difference. A positive elevation difference indicates that this segment is an uphill slope, and a negative one indicates a downhill slope. Subsequently, mark the turning points at the positions where the positive and negative signs change in the sign sequence. Each change in the elevation difference direction from positive to negative or from negative to positive is regarded as a slope direction change, and the corresponding path node is the potential start and end point of structure compression.

[0033] If there are multiple (not less than the original number of nodes within the path segment) such turning points within a path segment, and the lengths of adjacent slope direction change segments are not less than the set minimum segment length for structure analysis (such as set to 10 meters or more than 5 nodes), then it is considered that the path segment has a clear multi-slope configuration feature and can be used to construct a compression alternative scheme for the broken line path. The path segment is then marked as a structure compression candidate segment, and all its turning point indexes, slope direction distribution structure, and overall node composition are recorded. After this process, the paths in the set of connectable paths are divided into two categories: one is the path with a single direction and continuous slope segments, which is suitable for directly replacing the structure; the other is the path segment with a slope direction change structure, which has the potential for structure reconstruction through corner compression.

[0034] In S4, slope fluctuation and fold angle distribution analysis are performed on all sets of structural compression candidate segments, and a two-dimensional compression matrix for the alternative structure of the one-way height difference burden path segment is constructed.

[0035] Process the path node sequence of each candidate segment. The path node sequence is a set of spatial points sorted according to the path direction. Each node contains spatial coordinate information, including horizontal position (X, Y values in the plane coordinate system) and elevation data (H value). Two adjacent nodes together form a path unit segment, and each unit segment has direction, length, and elevation change attributes. The slope of each path segment is obtained by dividing its elevation difference by the horizontal projection distance, and the resulting numerical value represents the steepness of the terrain of this segment, presented in the form of a percentage or an angle.

[0036] After obtaining the slope value sequence, perform first-order difference processing on this sequence to extract the fluctuation degree of the slope change inside the path. Take the numerical difference between two consecutive slope values as an element of the new sequence to reflect the local change trend of the slope in space. During the difference processing, set the fixed difference window span to 1 to ensure that every effective slope change is accurately captured. For the N nodes included in the candidate segment, the difference result is N - 1 difference units. Record all differences in sequence and construct a difference sequence. After the sequence is completed, calculate three stable fluctuation indicators based on this sequence, including: average fluctuation value, maximum fluctuation value, and standard deviation value. To control the evaluation scale of the structural compression candidate segment, set the upper limit of the slope fluctuation intensity to 15%, and force the differences exceeding this value to be adjusted to the upper limit value. All calculation operations are performed item by item in the difference data set without abnormal tolerance or avoidance judgment. Through the above processing, finally generate a set of fluctuation characteristic indicators for each structural compression candidate segment and record them uniformly in the candidate segment feature mapping table, with fields including segment number, average slope fluctuation, maximum slope mutation, and fluctuation standard deviation.

[0037] Vectorize the path node sequence in the structural compression candidate segment, and establish a path segment vector set using the coordinates of the head and tail points. Each pair of adjacent nodes forms a path vector, and the vector construction is completed in the order of node numbers, and direction vector normalization processing is used to ensure that all vectors have a unified scale and directional expression. After constructing the vector set, calculate the included angle for every two consecutive path segment vectors, and generate a fold angle sequence based on the vector dot product rule. The fold angle is expressed in angle values (0° - 180°), and the precision of all included angle calculations is controlled to one decimal place to ensure the accuracy of the structural continuity expression. For each fold angle, synchronously calculate its cosine complement, that is, obtain the fold angle variation intensity index by subtracting the cosine value from 1.

[0038] All the cosine complements of the folding angles form a folding angle distribution characteristic sequence. Perform an average value operation on this sequence to obtain the overall folding angle variability index of the path segment. If there are few folding angles in the path and the average cosine complement is close to 0, it indicates that the structure is approximately a straight line; if the average value is close to 1, it means that the path turns multiple times and the structure has high compression potential.

[0039] After extracting the slope fluctuation characteristics and folding angle variability characteristics of each candidate segment for structure compression, perform a feature combination operation to form a two-dimensional structure complexity vector from these two types of characteristics. Each vector consists of two values. The first is the average value of slope fluctuations, and the second is the average value of the cosine complement of the folding angle. When constructing the feature vector, use the percentage normalization method to linearly map all feature values to the integer interval from 0 to 100 to ensure the measurability of the matrix after feature combination. Perform path segment mapping on each feature combination vector and bind it to the marked start and end node indices in the original one-way height difference burden path segment. The combined feature of each candidate segment is located in an interval in the original path, and this interval serves as a row in the two-dimensional compression matrix, representing the original structure segment being analyzed; the columns of the matrix correspond to the numbers of all available candidate segments for replacement.

[0040] After the two-dimensional compression matrix is constructed, assign a compression score value to each matrix cell. This value is obtained by weighted summation of the slope fluctuation component and the folding angle variability component according to a fixed ratio, and the ratio weights can be set according to the construction priority. For example, in a construction scenario where the proportion of foundation excavation is relatively high, set the slope fluctuation weight to 70% and the folding angle weight to 30%. All score values are stored as integers, and set a compression effective threshold to eliminate candidate segments with a score higher than 80, and retain the path segments with strong structural compressibility for path optimization search.

[0041] In S5, based on the two-dimensional compression matrix of the alternative structure, construct a structure-weighted connection graph, perform a continuous path minimum-weight search and splice the nodes to establish an alternative construction path.

[0042] Construct start and end node pairs for each candidate segment to form the edge elements in the connection graph. In the connection graph, each path node is mapped to a vertex in the graph, and the candidate segment for structure compression serves as the edge connecting two adjacent nodes. Traverse each cell of the compression matrix, extract the corresponding candidate segment structure score and path index, and mark it as a valid edge in the connection graph. Only the edges with a score value less than the set compression acceptance upper limit (such as within 60 points) are marked as compression valid and written into the edge set of the connection graph. At the same time, set the start and end node mapping relationship for each candidate segment and establish an index table from nodes to edges, so that the graph structure has complete topological information and reverse query capabilities. During the construction process, perform edge continuity constraint judgment. If the end point and start point nodes of two candidate segments are inconsistent, or there is an index dislocation, then eliminate the connection between the edges to prevent broken links from appearing in the graph structure.

[0043] The edge weight calculation consists of three key indicators: slope fluctuation characteristic value, angle variation characteristic value and path segment length value. Based on the previously extracted structural compression features, the three indicators are assigned fixed weights and then linear weighting is performed on the basis of normalization. Among them, slope fluctuation is an important parameter for evaluating path stability, accounting for 50% of the total score weight; angle variation reflects the path turning rate, and the weight is set to 30%; the longer the path length is, the more favorable it is for compression continuity, and its weight is set to 20%. If some engineering scenarios are more sensitive to a certain feature, such as tunnel construction with extremely small slope tolerance, the slope fluctuation weight is allowed to be increased to 70%. The weighted calculation is performed edge by edge during the connection graph construction phase, and the three indicators are calculated using a unified scoring function to generate an edge weight value in the range of 0 to 100. For path segments with a score of more than 70, they are marked as structural compression risk segments and do not participate in subsequent path searches. The weight results of all valid edges are written into the edge weight field of the connection graph, and the edge index library is updated synchronously for weighting judgment when quickly searching for path segments.

[0044] For each unidirectional height difference burden path segment, the minimum weighted path search operation under the structural continuity constraint is performed. This operation selects a set of path segment sequences with continuous splicing and minimum structural complexity from all possible compression candidate segment combinations as the optimal alternative path. The search process uses the starting node and the ending node of the original path segment as the boundary, which are set as the search starting point and search target. In the connection graph, the search framework is constructed based on the Dijkstra algorithm, and the path costs of all reachable paths in the graph are accumulated based on the set edge weights as the path costs. During the search process, only the path sequences with continuous structure are retained, that is, the path extension can only be established when there is a legal edge index between the current node and the next node. Path segment combinations that do not meet the continuity of the start and end nodes or are inconsistent in direction are discarded to avoid path configurations with structural breaks or reentry. The upper limit of the path length is set to 1.5 times the original path segment to avoid large-scale detours. At the same time, an upper limit is set on the number of branch paths in the search results, and only the top three paths with the best structural continuity are retained to reduce the pressure of subsequent path integration operations. All candidate paths record their path node sequence, corresponding candidate segment index and path cumulative weight value.

[0045] The node lists of each candidate segment are spliced ​​segment by segment to form a complete, uninterrupted, and structurally continuous path segment. During the splicing process, the coordinate consistency check is performed on the starting node of each segment and the end node of the previous segment to confirm the continuity between all segments. If there is a discrepancy between the end node and the first node of the next segment, the path correction operation is performed immediately to fill the gap by interpolation or node merging to ensure structural closure. After the splicing is completed, a unique path number is regenerated for the path segment and marked as an "optimized alternative path segment" to replace the original one-way height difference burden path segment. The alternative path segment retains the starting and end positions of the original path segment, and has lower structural complexity and better compression continuity. Record all node information of the path segment, the candidate segment number to which it belongs, the cumulative compression score of the path, and the successful structural compression mark.

[0046] In S6, the alternative construction path is merged into the initial construction path line by replacing the same nodes. Specifically, the node indexes of the starting point and the end point of the alternative path segment in the initial construction path line structure are extracted, the structure deletion operation is performed on the original path node sequence within the replacement index interval, and the intermediate node sequence of the alternative path segment is inserted into the interval in sequence.

[0047] Extract the index positions of the start and end nodes of the replacement path segment in the construction path primary line. Here, the first and last nodes of the replacement path segment are the replacement boundary points of the original path segment, and their positions have been mapped in the original path through the structural compression mapping operation. Therefore, directly locate the start index and end index of the replacement segment, and record them as the replacement start position and replacement end position respectively. This index interval is the specific position range of the replaced path segment in the original path structure. After completing the extraction of the start and end indexes, perform a structured node deletion operation on the construction path primary line structure. The specific operation is: remove all intermediate nodes between the start and end indexes from the path primary line node sequence, and only retain the index structure corresponding to the original position of the first and last nodes of the replacement path segment, so that the path structure forms an empty segment to be inserted after the deletion operation. This operation does not change the node numbering logic of the original path, but only adjusts the position order in the structure array to ensure the synchronization consistency of the numbering and spatial position.

[0048] Perform insertion processing on the intermediate node sequence of the alternative path segment. The inserted node sequence does not include the start and end nodes, but only all the intermediate nodes from the second node to the penultimate node, to ensure that the alternative path segment does not result in duplicate start points or broken end points. All intermediate nodes are inserted into the empty section of the original path initial line structure in the order of the nodes when the original alternative path segment was spliced. Assign a new structural position index to each inserted node, and reconstruct the entire node sequence in path order, updating its connection relationship in space. To verify the continuity of the inserted structure, after the node insertion is completed, perform a spatial connection check on the connection nodes on both sides of the alternative path segment to confirm that the start point of the newly inserted segment forms a closed vector chain with the end point of the previous segment, and the end point forms a closed vector chain with the start point of the subsequent segment in space. If the position deviation at the connection of the inserted segment exceeds the set error threshold (for example, within 0.5 meters), perform interpolation fine-tuning or node position insertion correction operations to ensure smooth connection and complete structure.

[0049] Output the updated node sequence as the new initial line of the construction path. The original unidirectional height difference burden segment in the structure has been replaced by the compressed structure replacement segment, and the path continuity, spatial consistency, and construction adaptability have all been updated synchronously. This path structure is used as the input of the basic path for subsequent construction drawing generation, resource allocation optimization, and scheduling path linkage.

[0050] The above formulas are all dimensionless and take their numerical calculations. The formulas are obtained by collecting a large amount of data for software simulation to get a formula closest to the actual situation. The preset parameters and threshold selection in the formulas are set by technicians in this field according to the actual situation.

[0051] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wired (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer, or a data storage device such as a server or data center that includes one or more collections of available media. The available media can be magnetic media (such as floppy disks, hard disks, magnetic tapes), optical media (such as DVDs), or semiconductor media. The semiconductor media can be a solid-state drive.

[0052] Those of ordinary skill in the art can realize that the modules and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. A professional technician can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0053] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and modules described above can refer to the corresponding processes in the foregoing method embodiments and will not be repeated here.

[0054] In several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is only a logical function division, and there can be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings, direct couplings, or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of devices or modules can be in electrical, mechanical, or other forms.

[0055] The module described as a separation component may or may not be physically separated. The component shown as a module may or may not be a physical module. It may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0056] In addition, in each embodiment of this application, the functional modules can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module.

[0057] If the above-mentioned function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of this application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0058] As described above, the above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all of them should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

[0059] Finally: The above is only the preferred embodiment of the present invention and is not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An optimization analysis method for the construction path planning of underground pipelines, characterized in that, It includes the following steps: S1: Collect elevation grid data within the layout range of the target mountain pipeline, and generate a continuous path slope direction sequence based on the initially approved construction path; S2: Identify the unidirectional slope sections in the continuous path slope direction sequence, and delimit the unidirectional high-voltage path sections; S3: Based on the start and end boundary points of the unidirectional high-voltage path sections, search for the set of candidate sections for lateral alternative structure compression in the laterally adjacent space; S4: Perform slope fluctuation and fold angle distribution analysis on all sets of candidate sections for structure compression, and construct a two-dimensional compression matrix for the alternative structure of the unidirectional height difference burden path section; S5: Based on the two-dimensional compression matrix of the alternative structure, construct a structure-weighted connection graph, perform continuous path minimum weighted search and splice nodes, and establish an alternative construction path; S6: Incorporate the alternative construction path into the initially approved construction path by replacing the same nodes, and generate an optimized construction path plan.

2. The optimized analysis method for the construction path planning of underground pipelines according to claim 1, characterized in that, In S1, collecting elevation grid data within the layout range of the target mountain pipeline and generating a continuous path slope direction sequence based on the initially approved construction path specifically includes: In the mountain target pipeline layout area, perform sampling dot matrix generation on the elevation surveying data, construct an elevation dot matrix space corresponding to the terrain undulation, and the dot matrix space is represented in the form of grid data; Generate equally spaced nodes along the linear direction of the initially approved construction path to form a set of path node sequences with position indexes; Based on the set of path node sequences, construct the spatial polyline vector structure of the initially approved path, and map it to the elevation dot matrix space. Calculate the elevation difference between adjacent path nodes in the elevation dot matrix space, and generate a continuous path slope direction sequence based on the calculation results.

3. An optimization analysis method for the construction path planning of underground pipelines according to claim 1, characterized in that, In S2, identifying the unidirectional slope sections in the continuous path slope direction sequence and delimit the unidirectional high-voltage path sections specifically includes: Based on the elevation differences between path nodes in the continuous path slope direction sequence, identify the structural sections with continuous and monotonic changes in slope direction trends, and integrate the corresponding structural sections into a set of unidirectional slope sections based on the slope direction trends; Perform equally long sliding window segmentation within the set of unidirectional slope sections to construct a group of sub-intervals with a fixed node span; Continuously superimpose the elevation differences between path nodes within each sub-interval of the group of sub-intervals, identify the sections where the cumulative height difference exceeds the set threshold, and label the corresponding sections as unidirectional height difference burden path sections.

4. The optimized analysis method for the construction path planning of underground pipelines according to claim 1, characterized in that, In S3, based on the start and end boundary points of the unidirectional high-voltage path sections, searching for the set of candidate sections for lateral alternative structure compression in the laterally adjacent space specifically includes: Extract the start and end node positions of the unidirectional height difference burden path section, and construct a lateral space offset band structure with the paragraph direction as the baseline; According to the preset construction path direction angle threshold and maximum elevation difference threshold, delimit the path offset search space in the lateral space offset band structure, and select several alternative path nodes according to the construction condition constraints; Based on the alternative path nodes, generate a set of connectable paths between the start and end nodes within the path offset search space, and record the elevation sequences of the path nodes corresponding to each path section; Extract the positive and negative signs of the elevation differences and mark the turning points for the elevation sequences of each path section in the set of connectable paths, and classify the path node sequences with slope turning structures into the set of candidate sections for structure compression.

5. The optimization analysis method for the construction path planning of underground pipelines according to claim 1, wherein In S4, slope fluctuation and fold angle distribution analysis is performed on all sets of structural compression candidate segments, and constructing a two-dimensional compression matrix for the alternative structure of the one-way height difference burden path segment specifically includes: In the path node sequence of the set of structural compression candidate segments, the elevation difference and horizontal distance between adjacent nodes are sequentially extracted to generate a sequence of slope values between nodes; Perform a first-order difference process on the sequence of slope values between nodes, and construct a fluctuation feature expressing the degree of slope fluctuation based on the difference processing results; Map the path node sequence of the structural compression candidate segment to a set of line segment vectors, establish a fold angle distribution sequence based on the included angle between adjacent vectors, and construct a fold angle variation feature according to the fold angle distribution sequence; Perform feature combination on the slope fluctuation features and fold angle variation features of all compression candidate segments, map the combined features to the path start and end node indexes corresponding to the one-way height difference burden path segment, and construct a two-dimensional compression matrix for the alternative structure.

6. The optimization analysis method for the construction path planning of underground pipelines according to claim 5, characterized in that The method of establishing a fold angle distribution sequence based on the included angle between adjacent vectors and constructing a fold angle variation feature according to the fold angle distribution sequence is to calculate the cosine complement of all fold angles in the fold angle distribution sequence, and use the average value of the cosine complement as the fold angle variation feature of the corresponding structural compression candidate segment.

7. An optimized analysis method for the construction path planning of underground pipelines according to claim 1, characterized in that, In S5, based on the two-dimensional compression matrix of the alternative structure, construct a structure-weighted connection graph, perform a continuous path minimum weighted search and splice nodes to establish an alternative construction path, specifically including: Based on the two-dimensional compression matrix of the alternative structure of the one-way height difference burden path segment, construct a structure-weighted connection graph with connected nodes, and map the corresponding structural compression candidate segments in the two-dimensional compression matrix to the effective edge index set in the structure-weighted connection graph; Among them, the effective edge weight of the structure-weighted connection graph is obtained by weighted operation of the fluctuation feature, fold angle variation feature and path length of the compression candidate segment; In the structure-weighted connection graph, with the start and end node order of each structural compression candidate segment as the path search constraint, perform a minimum weighted path search under the structural continuity constraint; The path nodes of each structural compression candidate segment in the obtained minimum weighted path are sequentially spliced into a continuous path segment as the alternative construction path.

8. The optimization analysis method for the construction path planning of underground pipelines according to claim 1, characterized in that In S6, the alternative construction path is merged into the initial construction path by the method of replacing the same nodes. Specifically, the node indexes of the start and end points of the alternative path segment in the initial construction path structure are extracted, the original path node sequence in the replacement index interval is subjected to a structure deletion operation, and the middle node sequence of the alternative path segment is sequentially inserted into this interval.

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