CN113032876B

CN113032876B - Method and system for laying interchange channel for automatically changing existing road along railway

Info

Publication number: CN113032876B
Application number: CN202110295577.XA
Authority: CN
Inventors: 蒲浩; 谢淑敏; 梁柱; 李伟; 宋陶然; 赵璐
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2022-05-24
Anticipated expiration: 2041-03-19
Also published as: CN113032876A

Abstract

The invention discloses a method, a system, a terminal and a readable storage medium for laying an interchange channel for automatically changing an existing road along a railway, wherein the method comprises the following steps: step S1: constructing an optimization model of the road and railway interchange channel line; step S2: dividing a research area into unit grids, and decomposing path search into two sections of non-cross section search and cross section search; step S3: performing path search on the two non-crossed sections and the crossed section based on the optimization model; step S4: and splicing and integrating the N paths, the M paths and the P crossed section local lines in the step S3 to form a plurality of complete lines, determining an optimal line by taking an optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme. The method is decomposed into path search of non-crossing sections and crossing sections, coupling interaction of connecting points and crossing points is weakened, and optimization of the highway and railway overpass channels is achieved.

Description

Method and system for laying interchange channel for automatically changing existing road along railway

Technical Field

The invention belongs to the technical field of railway design, and particularly relates to a method, a system, a terminal and a readable storage medium for laying an interchange channel for automatically changing an existing road along a railway.

Background

The railway is an important infrastructure of the country, is a main artery of national economy, and plays an important role in the development of the economy and the society of China. In order to meet the requirement of road transportation, the constructed roads and the constructed roads are increased year by year, and the existing road networks are more dense. In the railway construction process, a large number of intersections are formed between existing roads in many cities and areas and existing or newly-built railway lines and are limited by the intersection angles, effective clearance, line shapes and the like, in order to ensure the transportation safety and traffic capacity of the existing roads, illegal roads are inevitably rebuilt, and under the condition of limited time and energy, engineers usually only subjectively compare a plurality of satisfied constraints according to own experiences, and the feasible scheme for controlling investment makes final decisions, so that more valuable schemes are possibly omitted. Therefore, an intelligent design method for the overpass of the roads and the railways, which not only considers the constraints of road construction, road network intersection and the like, but also meets the aim of saving engineering investment, is urgently needed.

Road and railway interchange channel optimization belongs to a category under a line optimization framework, and compared with line optimization between two fixed end points, road network intersection and the connection enhancement constraint of the existing road need to be considered. The research on the road and railway overpass passage at home and abroad is mainly divided into three stages: in the first stage, only a near-optimal solution alternative set is provided for each road intersection, comparison and selection are carried out in a limited scheme, and an optimal route scheme meeting the constraint and the investment cost is selected. And a second stage: an accurate solution is provided, but the change of the terrain and complex constraint conditions are difficult to be represented by an explicit function, and the theoretical defects exist. And a third stage: with continuous innovation of optimization methods and increase of computer computing capacity, a heuristic algorithm independent of explicit functions is proposed, wherein genetic algorithms are widely applied to interchange channels, but are still limited to manually giving an initial line scheme.

Considering the investment cost of the line as a specific distance between the starting point and the ending point of the interchange channel, the design of the interchange channel can be converted into the shortest path searching problem between the starting point and the ending point. Aiming at the condition that the starting point and the ending point of a road and a railway interchange channel are not fixed, the invention needs to be discussed urgently how to realize the line optimization.

Disclosure of Invention

The invention aims at the problems that an existing road is intersected with a newly-built railway, and an intersection section interchange channel is required to be established to meet the requirements of road design, road network intersection constraint, the traffic capacity of the existing road is maintained, a local road is reconstructed, and an optimal reconstruction scheme is searched for, provides a brand-new technical thought to realize the design of a reconstruction section, provides a layered optimization strategy to solve the positions of a connection point of the reconstruction section and the existing road and the intersection point of the reconstruction section and the railway, and decomposes a core problem into non-intersection section sub optimization and intersection end and non-intersection section two-stage recombination to ensure that the changes of the connection point and the intersection point are mutually independent, weaken the coupling interaction of the connection point and the intersection point, and realize the optimization of the highway and the railway interchange channel.

On one hand, the invention provides a method for laying an interchange channel for automatically changing an existing road along a railway, which comprises the following steps:

step S1: the method comprises the following steps of constructing an optimization model of a road and railway interchange channel line, wherein the optimization module comprises: studying decision variables, constraint conditions and optimization functions in the region;

step S2: dividing a research area into unit grids, determining a connection starting and ending point cell set S, E of a local reconstructed road and the existing road in the research area and a cell set L, R of the left side and the right side of the railway according to the existing road and the railway, and further decomposing path search into two sections of non-cross section search and cross section search;

the path between the cell set S and the cell set L on the same side of the railway and the path between the cell set E and the cell set R on the same side of the railway are the two sections of non-crossed section paths; the path between the cell set L and the cell set R is a cross section path;

step S3: performing path search on two non-crossed sections and crossed sections based on the optimization model;

performing line search on the two non-crossed sections to obtain M paths between a cell set S and a cell set L and N paths between a cell set E and a cell set R; and carrying out path search on the cross section to obtain H cross section local lines;

searching by taking an optimization function in the optimization model as an objective function, wherein the searched line meets the constraint condition in the optimization model;

step S4: and S3, splicing and integrating the N paths, the M paths and the H crossed section local lines to form a plurality of complete lines, determining an optimal line by taking the optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme.

Optionally, in the step S3, a DT algorithm is adopted in the process of performing path search on two non-intersecting segments based on the optimization model, and the generalized distance value of the cell in the DT algorithm is defined by the optimization function, and the implementation process is as follows:

for the path search process between the set of cells S and the set of cells L:

a-1: taking the cells in the cell set L as fixed endpoints, and selecting a cell set L [ L ]₁,L₂,...,L_p]One cell L_iAs a fixed end point of the S → L section path, p is the total number of cells in the cell set L;

a-2: with a unit cell L_iAdopting a DT algorithm to search for a fixed end point to obtain a DT value of each cell in the cell set S, and if the DT value of the cell is not positive and infinite, reserving the cell and forming a local path; otherwise, abandoning a local path corresponding to the cell, wherein the cell L is used as the cell_iObtaining a plurality of feasible paths for the fixed end points;

a-3: selecting the path with the minimum DT value from the feasible paths as the cell L_iA path from the cell set S to the cell set L which is a fixed end point;

a-4: traversing the cells in the cell set L, and repeating the steps A-1-A-3 to finally obtain paths between the M cell sets S and the cell set L;

for the path search process between the set of cells E and the set of cells R:

b-1: using the cells in the cell set R as fixed end points, selecting the cell set R [ R ]₁,R₂,...,R_q]One cell R_iAs the fixed end point of the E → R section path, q is the total number of the cells in the cell set R;

b-2: in a unit cell R_iAdopting a DT algorithm to search for a fixed end point to obtain a DT value of each cell in the cell set E, if the DT value of the cell is greater than 0, reserving the cell and forming a local path; otherwise, abandoning a local path corresponding to the cell, wherein the cell R is used as the cell_iObtaining a plurality of feasible paths for the fixed end points;

b-3: selecting the path with the minimum DT value from the feasible paths as the cell R_iA path from cell set E to cell set R for a fixed endpoint;

b-4: and traversing the cells in the cell set R, and repeating the steps B-1-B-3 to finally obtain paths between the N cell sets E and the cell set R.

Optionally, step A-2 with cell L_iThe process of searching for the DT algorithm for the fixed endpoint to obtain the DT value for each cell in the set S of cells is:

a-2-1: preprocessing the search area, namely, the search area is determined according to the research area on one side of the cell set S, wherein any cell in the search area is connected to the fixed endpoint L_iIs using the maximum limit gradient i_maxAnd the allowable spread coefficient gamma, the following formula is satisfied:

wherein R (R)_x,R_y,R_z) Xyz coordinates, LR (LR), representing any cell within the search area_x,LR_y,LR_z) Represents a fixed end point L_iXyz coordinate of (a)_maxRepresenting the maximum limit slope of the road, and gamma representing a line expansion coefficient;

if not, marking the cell in the search area as a forbidden unit without participating in the bidirectional scanning process;

a-2-2: initializing generalized distance values of cells of all non-forbidden cells in a search area;

a-2-3: and performing bidirectional scanning on the search area, and updating the generalized distance value of each cell to form a generalized distance map, wherein the generalized distance value of each cell in the generalized distance map is the DT value of the cell.

Optionally, the process of constructing the generalized distance map in step a-2-3 is as follows:

a-2-3-1: constructing a neighborhood template, and placing the central position of the neighborhood target on a cell when each cell is scanned;

when any cell P is scanned, taking P as a local line starting point, and taking any cell G in the neighborhood template as a local line terminal point;

a-2-3-2: s [ S ] when cell G does not belong to the search region₁,S₂,...,S_m]Then, straight lines are used to connect the cells G with P; or when the cell G belongs to S [ S ]₁,S₂,...,S_m]When the target cell is connected with the cell set S, using curve smooth connection, wherein a is the direction of a forward path connected with the target cell, b is the existing road direction of the cell G, and m is the number of cells in the cell set S;

a-2-3-3: connecting the cells P and G to obtain a local line and form a local line scheme with a structure, judging whether the local path scheme meets the constraint, if not, abandoning the local line, switching to the step A-2-3-1, and reselecting the cells in the field template; if yes, switching to the step A-2-3-4;

step A-2-3-4: calculating a generalized distance value between the cell P and the cell G, and updating the generalized distance value of the cell P;

step A-2-3-5: iterative execution A_2-3-1、A_2-3-2、A_2-3-3、A_2-3-4And in the scanning process, until the generalized distance value of each cell is not changed any more, obtaining a generalized distance map.

Optionally, the process of performing path search on the cross section in step S3 to obtain H cross section local lines includes: iteratively searching local lines between the cell set L and the cell set R, and reserving the local lines meeting the constraint condition, specifically as follows:

with a sheetTaking any cell Li in the cell set L as a center, making a perpendicular line to the railway, taking the perpendicular line as an angular bisector, and respectively rotating the perpendicular line by 90-A degrees from left to right_minObtaining a straight line a and a straight line b, wherein Amin is the minimum crossing angle meeting the standard requirement;

in the cell set R, Q cells contained in a sector area formed by the straight line a and the straight line b are a sector feasible solution cell set;

respectively and linearly connecting the cell Li with Q cells in the fan-shaped feasible solution cell set to form Q local lines;

detecting whether the Q local lines meet constraint conditions or not, and if not, rejecting the Q local lines; if yes, generating a plan, a vertical section, a bridge and a tunnel line scheme of the local line;

and iteratively searching all the cells in the cell set L according to the process to generate a local line scheme of P crossed sections.

Optionally, in step S4, performing curve fitting on the plane and the vertical section based on the optimal route plan to obtain a final route plan, where: selecting characteristic points in the path as plane intersection points by adopting a chord tangent offset method according to the optimal line scheme, and matching the minimum radius of a circular curve and the minimum curve length according to specifications to generate an initial plane line; initializing a longitudinal section scheme according to the minimum earth and stone engineering quantity on the basis of a plane initial line scheme; optimally, the line is optimized integrally to obtain a final optimized planar and longitudinal line scheme, for example, the line is optimized integrally by using a Nonlinear mesh adaptive direct search algorithm (NOMAD). Since this process is a prior art implementation process, it is not specifically described.

Optionally, the decision variables in the study region in step S1 are represented as:

plane intersection HIP's (X)_H,Y_H,R_H,L_H0,L_H1)；

Vertical section slope change point VIP's (K)_V,H_V,R_V)；

ReconstructionBridge and tunnel MBU's (KB) on line_S,KB_E,KU_S,KU_E)；

Starting and ending points of the reconstructed line and a cross point VCC' S (I, S, E);

X_Hand Y_HThe abscissa and ordinate of the plane intersection, R_HRadius of intersection corresponding to the intersection of planes, L_H0And L_H1The lengths of the front relaxation curve and the rear relaxation curve corresponding to the plane intersection point; k_VAnd H_VMileage and elevation at variable slope points, R_VThe radius of a vertical curve corresponding to the variable slope point; KB_SAnd KB_EKU for the starting and ending mileage of a bridge_SAnd KU_EStarting mileage and ending mileage corresponding to the tunnel; i represents an intersection of the optimized line scheme and a newly-built railway, S represents an initial connection point of the optimized line scheme on an existing road, and E represents an end connection point of the optimized line scheme on the existing road;

the optimization function in step S1 is the minimum engineering cost, and includes: the earthwork cost, the road surface cost, the road right cost, the bridge engineering cost and the tunnel engineering cost are expressed as follows:

F(HPI's,VPI's,MBU's,VCC's)＝min(C_E+C_P+C_R+C_B+C_U)

in the formula, F (HPI's, VPI's, MBU's, VCC's) is the engineering cost on the basis of decision variables, C_E,C_P,C_R,C_B,C_URespectively, earth and stone engineering cost, pavement cost, road right cost, bridge engineering cost and tunnel engineering cost;

the constraints in the optimization model include: geometric linear constraint, cross constraint, connection constraint and existing structural constraint.

Optionally, in the step S2, in the process of dividing the study area into the cell grids, the calculation formula of the width of the cell grid is as follows:

width＝2T_min+J_min

J_minindicates the minimum clip line length, T_minThe length of the minimum tangent at the maximum rotation angle is expressed byCalculating the formula:

in the formula, alpha_maxMaximum allowable turn angle, R, for line design_minThe minimum curve radius of the road.

In a second aspect, the present invention provides a system for automatically changing the layout of an interchange lane of an existing road along a railway, comprising:

the optimization model building module is used for building an optimization model of a road and railway interchange channel line, and comprises: researching decision variables, constraint conditions and optimization functions in the region;

the grid division module is used for carrying out unit grid division on the research area;

the search road section dividing module is used for determining a connection starting and ending point cell set S, E of a local reconstructed road and the existing road in the research area and a cell set L, R of the left side and the right side of the railway according to the existing road and the railway, and further decomposing the path search into two sections of non-cross section search and cross section search;

the non-cross section path searching module is used for searching paths of the two non-cross sections based on the optimization model;

the cross section path searching module is used for searching a path of the cross section;

performing line search on the two non-crossed sections to obtain M paths between a cell set S and a cell set L and N paths between a cell set E and a cell set R; and carrying out path search on the cross section to obtain P cross section local lines;

an optimal route obtaining module, configured to splice and integrate the N paths, the M paths, and the P cross section local routes in step S3 to form a plurality of complete routes, and determine an optimal route by using the optimization function as a target function;

and the final line scheme acquisition module is used for performing curve fitting on a plane and a vertical section based on the optimal line scheme to obtain a final line scheme.

In a third aspect, the present invention further provides a terminal, including a processor and a memory, where the memory stores a computer program, and the processor calls the computer program to execute: a method for laying overpasses along railway lines automatically changes existing roads.

In a fourth aspect, the present invention also provides a readable storage medium storing a computer program, the computer program being invoked by a processor to perform: a method for laying overpasses along railway lines automatically changes existing roads.

Advantageous effects

Aiming at the conditions that the starting and ending points of a reconstructed road and the intersection points of a newly-built railway are not fixed, the starting and ending points of a line are subjected to connection constraint, the intersection points are subjected to cross constraint, and the line is subjected to a large number of geometric linear constraints and existing structure constraints in the design process of the road and the railway interchange channel, the layout method provided by the invention provides an optimization model of the road and the railway interchange channel line, wherein the optimization model comprises geographic information, optimization functions, constraints and decision variables. A hierarchical optimization strategy is introduced on the basis of an optimization model, the generation of a reconstruction section is divided into two stages of generation of a cross point and generation of a starting point and a finishing point of a reconstruction road, and a core problem is decomposed into a non-cross section sub-optimization stage and a cross section and non-cross section two-stage recombination stage, so that the generation of the connection point and the cross point are mutually independent, the coupling interaction between the connection point and the cross point is weakened, the optimization problem is simplified, and the intelligent optimization of the interchange channel between the road and the railway is realized.

Further comparing the scheme generated by the layout method with an experienced manual design scheme, the result shows that the method can effectively improve the cost of local reconstruction road engineering under the condition of meeting all constraint conditions, and has the advantages of high automation degree, high efficiency, strong practicability and the like.

Drawings

FIG. 1 is a schematic view of a region of interest provided by an embodiment of the present invention.

Fig. 2 is an optimization model of the interchange lane route scheme between the road and the railway provided by the embodiment of the invention.

Fig. 3 is a schematic diagram of a cell width geometry according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of S, L, R, E cell sets provided by the embodiment of the present invention.

Fig. 5 is a schematic diagram of a neighborhood template and a bidirectional scanning direction in the DT algorithm according to the embodiment of the present invention.

FIG. 6 is a schematic diagram of the connection of local links in the reconstructed road S → L, E → R according to the embodiment of the invention (1: P does not belong to S; 2: P belongs to S).

FIG. 7 is an optimized path tree for S → L segment generation provided by embodiments of the present invention.

Fig. 8 is a schematic diagram of a local route connection of a reconstructed road L → R segment according to an embodiment of the present invention.

Fig. 9 is a schematic diagram of a chordal displacement method according to an embodiment of the present invention.

Fig. 10 is a schematic flow chart of the layout method provided in embodiment 1 of the present invention.

Detailed Description

The invention provides a method, a system, a terminal and a readable storage medium for laying overpasses for automatically changing an existing road along a railway, wherein the laying method is used for solving the design problem of local road reconstruction and finding an optimal reconstruction scheme on the basis of maintaining the communication capacity of the existing road when the existing road is crossed with a newly-built railway. The present invention will be further described with reference to the following examples.

Example 1:

as shown in fig. 10, the method for laying an interchange channel for automatically changing an existing road along a railway provided by the invention comprises the following steps:

S₁: and establishing an optimization model of the road and railway interchange channel line.

A comprehensive geographic information model of a research area is established, plane intersection point information (including intersection point coordinates, radius, front and back gentle curve length), longitudinal section variable slope point positions (including mileage, elevation and vertical curve radius), bridge and tunnel positions (including mileage and elevation) and intersection points of a reconstructed road and a newly-built railway are introduced, and two connection points of an existing road are used as decision variables. The lowest comprehensive cost is found out as an optimization function (objective function), and various constraint conditions (including linear geometric constraint, cross constraint, connection constraint and existing structure constraint) are considered to establish a road and railway interchange channel scheme optimization model.

For the research area, in this embodiment 1, an elliptical area is constructed along the existing road at a distance X meters from the intersection position I of the existing road and the newly-built railway (the distance is generally determined by designers according to experience, and since the distances between the road and the railway overpass are both less than 1km, the distance is taken to be 500 m.) and two points a and B are identified. Two points A and B are taken as the focus of the ellipse, and the expansion coefficient gamma is 2i_max/i_DIs eccentricity of, wherein i_DAverage slope of ground elevation, i_maxIs the maximum limit gradient of the road. The method comprises the steps of taking a research area as an external quadrangle of the ellipse, subdividing the research area into unit squares with the width of w, and obtaining a Comprehensive Geographic Information Model (CGIM) comprising geographic information such as terrain (elevation), geology (geotechnical characteristics), unit cost (engineering unit price information), existing buildings (factories, roads, railways and residential areas) and the like.

The average slope i of the ground elevation is_DMaximum limit gradient i of road_maxAre parameters for the entire existing road in the area of study. In other possible embodiments, the scope of the research area may be determined by selecting other rules according to the locations of the existing roads and newly-built railways, which is not specifically limited by the present invention.

A mathematical expression of the objective function is established by determining decision variables, wherein the decision variables selected in this embodiment 1 are expressed as:

plane intersection HIP's (X)_H,Y_H,R_H,L_H0,L_H1)；

Vertical section slope-changing point VIP's (K)_V,H_V,R_V)；

Bridge and tunnel MBU's (KB) of reconstruction segment_S,KB_E,KU_S,KU_E)；

The start and end points of the reconstructed segment and the crossover point VCC' S (I, S, E).

In HIP: x_HAnd Y_HThe abscissa and ordinate of the plane intersection, R_HRadius of intersection corresponding to the intersection of planes, L_H0And L_H1The lengths of the front relaxation curve and the rear relaxation curve corresponding to the plane intersection point.

In VIP: k_VAnd H_VMileage and elevation at variable slope points, R_VThe radius of the vertical curve corresponding to the variable slope point.

In the MBU: KB_SAnd KB_EKU for the starting and ending mileage of a bridge_SAnd KU_EAnd the initial mileage and the final mileage corresponding to the tunnel.

In VCC: i denotes the intersection of the optimized route plan with the newly built railway, S denotes the initial connection point of the optimized route plan on the existing road, and E denotes the final connection point of the optimized route plan on the existing road.

The objective function selected in this embodiment 1 is the lowest engineering cost, which includes the earth and rockfill engineering cost, the road right cost, the bridge engineering cost and the tunnel engineering cost. Namely, an objective function with the lowest comprehensive construction cost is constructed according to the engineering cost, and the specific expression is as follows:

F(HPI's,VPI's,MBU's,VCC's)＝min(C_E+C_P+C_R+C_B+C_U)

wherein the earthwork cost C_ECalculated by equation (1):

in the formula (I), the compound is shown in the specification,

in order to achieve the unit cost of digging,

in order to achieve a unit cost of fill,

for the unit cost of transporting earth to a landfill,

for the unit cost of transporting earth from the earth borrowing pit,

in order to excavate the square, the square is cut,

for fill volume, when calculating the total cost of transporting the earth to the landfill,

for the total volume of earthwork transported to the landfill site, when calculating the total cost of transporting earthwork from the earth borrowing pit,

the total volume of earth and stone blocks for transporting borrow soil from a soil borrowing pit.

Road surface cost C_PCalculated by equation (2):

C_P＝u_pWL (2)

in the formula u_pW is the unit cost of the pavement, W is the width of the pavement, and L is the length of the pavement.

Road right fee C_RCalculated by equation (3):

C_R＝n×w²×u_R (3)

wherein n is the total number of cells occupied by the optimized line (reconstruction segment) in the geographic information model, and w²Is the area of a cell, u_RIs the unit cost of the road right.

Bridge engineering cost C_BCalculated by equation (4):

in the formula u_BiIs the unit length cost, L, of the ith bridge_BiBridge length of i-th bridge, N_iTotal number of piers of ith bridge, C_AiIs the unit cost of the bridge pier, and z is the number of the bridges.

Tunnel engineering cost C_UCalculated by equation (5):

in the formula u_UiCost per unit length, L, of the ith tunnel_UiThe length of the ith tunnel and the number of the tunnels are h.

It should be noted that, in embodiment 1, the cost problem is considered, and the lowest reconstructed overall cost is taken as the objective function, in other feasible embodiments, the objective function may be set from other cost angles or more factors are considered to form the overall cost, which may be adaptively adjusted according to actual requirements, which is not specifically limited in the present invention.

Constraint conditions are as follows: geometric linear constraint, cross constraint, connection constraint and existing structural constraint are determined by consulting road linear design Specification (JTGD 20-2017).

(1): geometric linear constraint

1) It is noted that the search path has n1 intersection points (in this embodiment, the search path obtained by the DT algorithm is itself a zigzag, and the turning point of the zigzag is regarded as an intersection point), and the radius of the plane curve, the length of the included straight line, and the turning angle corresponding to the intersection point are R respectively_i，R_i，

The specific constraints are expressed as follows:

R_min、L_min、

the maximum curve radius allowed by the line plane, the minimum clamping line length allowed by the line plane and the minimum steering angle allowed by the line plane are respectively.

2) The total number of n2 slope-changing points on the vertical section of the search path is recorded, and the radius, the slope and the slope length of a vertical curve corresponding to the slope-changing points are respectively

The specific constraints are expressed as follows:

the minimum vertical curve radius allowed by the line vertical section, the maximum gradient allowed by the line vertical section, the minimum slope length allowed by the line vertical section and the maximum slope length allowed by the line vertical section are respectively.

(2): cross constraint

1) When the road is crossed with a newly built railway, a crossing angle A is formed_CShould not exceed a specified minimum intersection angle A_minAnd to make the road as orthogonal to the railway as possible:

A_min≤A_C≤90° (8)

2) the clearance at the intersection should ensure that there is sufficient distance between the road and the railway to ensure the driving safety of the vehicle:

Vh≤|H_road-H_rail| (9)

3) the road is at the intersection section, and the road must be kept straight to ensure good visibility during driving.

(3): connection constraint:

when local rebuild road is connected with existing road, in order to guarantee that the rebuild road can be connected smoothly, need guarantee that the starting and ending point of rebuild road is located existing road, and the azimuth angle of rebuild road and existing road at the junction should keep unanimous:

α_exist＝α_cross (10)

α_exist、α_crossthe line azimuth of the existing road at the intersection of the existing road and the reconstructed road and the line azimuth of the reconstructed road at the same position (namely the starting point of the reconstructed road) are obtained.

(4): the existing structural constraint can be divided into two types, namely a restricted area of an existing building determined in a comprehensive geographic information model and a structural requirement of a newly-built building.

1) A forbidden zone: the search path should avoid interfering with existing structures in the integrated geographic model (CGIM). Get set U_FAll the cells representing forbidden zones in the CGIM are represented; set U_CThe cells occupied by the search path. To ensure that the search path bypasses the forbidden region, U_FAnd U_CThe intersection of (c) must be null:

2) the structural requirements are as follows: the height and length of the bridge and the aperture of the tunnel should meet the specifications in road alignment design Specification (JTG D20-2017).

S₂: and dividing a research area into unit grids, determining a connection terminal cell set S, E of a locally reconstructed road and the existing road in the research area and a cell set L, R on the left side and the right side of the railway according to the existing road and the railway, and further decomposing the path search into two non-cross section searches and cross section searches. This exampleIn step S₂The specific implementation process is as follows:

S_2-1: a rectangular study area is acquired.

S_2-2: the rectangular research area is divided into unit grids with width, so that the requirement of minimum clamping line length and tangent length between the two unit grids is met. The width calculation formula is as follows:

width＝2T_min+J_min (12)

J_minindicates the minimum clip line length, T_minThe minimum tangent length at the maximum rotation angle is represented by the following formula:

in the formula, alpha_maxThe allowable maximum rotation angle is designed for the circuit, and generally 70-90 degrees is adopted, and R is_minIs the minimum curve radius of the road.

S_2-3: the set of cells S, E connecting the local rebuilt road with the existing road and the set of cells L, R on the left and right sides of the railway are defined. Taking the newly-built railway as a base line, and taking cells in the 1 st and 2 nd columns on the left side of the advancing direction of the newly-built railway as a left cell set L [ L ] near the railway in order to increase the diversity of the line schemes₁,L₂,...,L_p]Similarly, the cells in the 1 st and 2 nd columns on the right side of the advancing direction of the newly-built railway are taken as the right cell set R [ R ] near the railway₁,R₂,...,R_q]. Will be connected with L [ L ] by taking the newly-built railway line as the boundary₁,L₂,...,L_p]The set of cells for the existing road on the same side to pass through is taken as a set S [ S ] of connection starting points of the local reconstructed road and the existing road₁,S₂,...,S_m]Will react with R [ R ]₁,R₂,...,R_q]The set of cells for the existing road on the same side to pass through is taken as a connection terminal set E [ E ] of the locally reconstructed road and the existing road₁,E₂,...,E_n]. In other possible embodiments, the units may be grouped based on the location of existing roads and newly built railwaysThe range of the grid set is adjusted adaptively, and the invention is not limited to this, for example, the range of the cells is enlarged along the existing road or the range of the cells is enlarged along the newly built railway.

S₃: and performing line search on the two non-crossed sections by using a DT algorithm. In this embodiment, a DT algorithm is used to search for a path between the cell set S and the cell set L and a path between the cell set E and the cell set R on the same side, but in other feasible embodiments, a way of obtaining two non-intersecting paths based on an objective function and satisfying a constraint condition may also be applied to the present invention.

For the path search process between the set of cells S and the set of cells L:

a-4: and traversing the cells in the cell set L, repeating the steps A-1-A-3, and finally obtaining M paths between the cell set S and the cell set L, wherein M is less than or equal to p.

Similarly, the paths between the cell set E and the cell set R are searched to obtain the paths between the cell set E and the cell set R, wherein N is less than or equal to q, and q is the total number of cells in the cell set L.

The basic principle of the DT algorithm mentioned above is as follows:

distance transform is a common transform in graphics, converting an image into a grayscale image (distance map) in which the grayscale value of each cell is the minimum distance of the cell to its nearest background point (target point). The neighborhood template is formed by combining n multiplied by n unit cells, and can use a matrix M_dA representation in which the value of each element d (r → c) represents the local distance between the template center and the pixel in its neighborhood (row r, column c, cell). In the line design, the engineering cost is extended to a generalized distance. The neighborhood template is used to scan the area of interest in both forward and reverse directions.

Based on the principle of the DT algorithm, the search process of the invention by utilizing the DT algorithm is as follows:

S_3-2-1: the study area on the left side of the newly constructed railway line is preprocessed.

The cells in the study area should satisfy a high degree of accessibility, in a set of cells L₁,L₂,...,L_p]One cell L_iTaking the process of performing a path search on the cell set S as a fixed end point as an example, that is, the distance from any cell in the research area to the fixed end point Li must be ensured when the maximum limit gradient i is used_maxAnd the allowable line spreading coefficient gamma, the height difference between the two cells can be overcome, namely:

wherein R (R)_x,R_y,R_z) Coordinates representing any one cell in the left study area, LR (LR)_x,LR_y,LR_z) Indicating a fixed end point L selected from the railway vicinity units L_iCoordinate of (a), i_maxRepresents the road maximum limit slope, and gamma represents the line-spreading coefficient. If a cell fails the high accessibility test, i.e., conflicts with equation 14, then the cell is marked as a forbidden cell, at S_3-3-2The bidirectional scanning process as described inThe scanning of the exclusion zone will be omitted.

S_3-2-2: initializing generalized distance values V for all cells of the left study area_DTAs shown in equation 15, the fixed end point is 0, and the other pixels are all positive infinity. Generalized distance means that the concept of distance in distance variation is extended to a synthetic cost, namely the aforementioned (C)_E+C_P+C_R+C_B+C_U) Determining a composite cost, wherein the number represents a generalized distance value, D represents a free unit, the generalized distance value is positive infinity, and L_RRepresenting a fixed endpoint with a generalized distance value of zero, as in equation (15):

S_3-2-3: and starting from the upper left corner of the image, scanning all pixels of the non-forbidden unit in the sequence of forward (from top to bottom, from left to right) and backward (from bottom to top, from right to left), and updating the generalized distance values of the pixels to form a generalized distance map.

The construction process of the generalized distance map comprises the following steps:

S_3-2-3-1: a 5 x 5 neighborhood template is constructed, and the center of the neighborhood template is placed on the cells as each cell is scanned. When any cell P is scanned, taking P as a local line starting point, and enabling the center of the neighborhood template to coincide with P. And taking any cell G in the neighborhood template as a local line terminal.

S_3-2-3-2: to ensure that the partial line PG satisfies step S_1-4The connection constraint stipulates that when local line connection is carried out, the connection type of P and G is determined according to whether G belongs to S [ S ]₁,S₂,...,S_m]The treatment is divided into two cases, and the two cases are respectively treated, and the details are shown in the attached figure 6:

(1): when cell G does not belong to S [ S ]₁,S₂,...,S_m]When, a straight line is used to connect the cells G to P.

(2): when cell G belongs to S [ S ]₁,S₂,...,S_m]When the cell G is in the road direction, a is the forward path direction of the cell G. Meanwhile, step S needs to be satisfied_1-4The geometric linear constraint specifies.

S_3-2-3-3: a plane longitudinal plane linearity is formed after the cells P and G are connected, namely, a bridge, a tunnel and a roadbed are arranged according to a local path, and whether the local line meets corner constraint, self-intersection constraint, avoidance constraint and inevitable constraint required by the plane line or not is judged; the method comprises the following steps of limiting slope constraint, elevation accessibility constraint, elevation trend constraint and crossing constraint required by a longitudinal section line; the bridge height constraint, the bridge length constraint and the clearance constraint of the bridge; automatically laying a generated tunnel according to the line tunnel excavation depth boundary standard to determine whether the tunnel meets tunnel length constraint and geological condition constraint; whether the roadbed section meets the requirements of the slope direction and the geological conditions. If not, the local line scheme is removed, and the step S is carried out_3-2-4-1And reselecting the cells in the neighborhood template.

S_3-2-3-4: satisfies the step S_3-2-3-3And the various constraints calculate the generalized distance value between P and G, and if the generalized distance value satisfies the following conditions:

V_DT(G)+d(P→G)＜V_DT(P) (16)

the generalized distance value V of the current cell P is updated_DT(P) reaction of V_DT(P)＝V_DT(G) + d (P → G) and recording the row-column difference (Δ R, Δ C) between P and G, propagating the distance value from cell P to cell G. Otherwise, not updating and proceeding to step S_3-2-3-1And reselecting the cells in the neighborhood template.

S_3-2-3-5: iterative execution of S_3-2-3-1、S_3-2-3-2、S_3-2-3-3、S_3-2-3-4And in the scanning process, until the generalized distance value of each cell is not changed any more, forming a final distance map.

S_3-2-4: through step S_3-2-3The generalized distance graph is formed, DT values of all cells in the S set are searched, the cell (Si) with the minimum DT value is used as the shortest path end point taking Li as the target point, and the cell (Si) is recurred through delta R and delta CAnd a scheme of the shortest path from the cell Si to the target point, wherein the recursion process is the prior art, and the recursion is used for obtaining the local optimal line of the central position in each neighborhood template in the neighborhood template.

S₄: and (5) iteratively searching to obtain a local line of the cross section. In this embodiment 1, the non-cross section search is performed first, and then the cross section search is performed, but in other feasible embodiments, the cross section search is performed first, and then the non-cross section search is performed, or both are performed in parallel and synchronously.

Said step S₄The method specifically comprises the following steps:

S_4-1: taking the ith (i ═ 1,2,3 …, M) cell Li in L, making a perpendicular line to the newly-built railway with the center of the cell as shown in the attached figure 8, taking the perpendicular line as an angular bisector, and rotating the perpendicular line respectively from left to right by 90-A degrees_minThe included angle between the straight lines a and b and the newly-built railway is Amin (the minimum crossing angle meeting the specification requirement). The sector area formed by the straight lines a and b contains Q R₁,R₂,...,R_q]And the middle cell is called as a fan-shaped feasible solution cell set.

S_4-2: and connecting Li with any cell Rj in the fan-shaped feasible solution cell set by using a straight line to form a local line. Li is connected with the Q unit grids respectively to form Q local lines, and the crossing points of the Q local lines meet crossing angle constraint.

S_4-3: detecting vertical clearance constraint at the cross point I of the local line of the cross section, specifically according to cross constraint regulation in constraint conditions, rejecting the local scheme of the cross section without passing detection, and turning to S_4-6. Sequentially performing the step S through detection_4-4。

S_4-4: by reaction of a compound with S_3-2-3-3Same step to generate L_iAnd R_jThe detailed plan, the vertical section, the bridge and the tunnel line scheme.

S_4-5: repeating the step S_4-2、S_4-3、S_4-4、S_4-5Iterative Li and sector feasible solution cell setAnd (4) connecting the unit grids to finally generate no more than Q cross section local line schemes.

S_4-6: iteratively searching all cells in the L, and repeating the step S_4-1、S_4-2、S_4-3、S_4-4、S_4-5And generating a local line scheme of not more than M × Q cross sections, namely H cross section local lines.

S₅: and integrating the generated two non-crossed sections and the crossed section to form a plurality of complete lines, determining an optimal line by taking the optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme. The method specifically comprises the following steps:

S_5-1: combining the S → L section path corresponding to the cell Li and the E → R section path corresponding to the cell Rj in each cross section local scheme to form a complete line, and recording the generalized distance value of the refreshing line S → L → R → E as D_i,jD is_i,jAdding distance set U_Di,j。

S_5-2: repeating step S_5-1And obtaining corresponding generalized distance values of the complete local circuit until the M-Q cross section local circuit schemes.

S_5-3: set of generalized distance values U_Di,jSorting according to generalized distance values from small to large, minimum generalized distance scheme min (D)_i,j) The optimal scheme with the lowest comprehensive cost shows that the ith cell in the L is connected with the jth cell in the R, and the optimal route is formed by combining the S → L and the E → R section route.

S_5-4: according to step S_5-3And selecting characteristic points in the path as plane intersection points by adopting a chordal tangent offset method, and matching the minimum radius of the circular curve and the curve length according to the specification to generate an initial plane line.

S_5-5: and initializing a longitudinal section scheme according to the minimum earth and stone engineering quantity on the basis of the plane initial line scheme.

S_5-6: on the basis of the optimization model of the interchange channel route scheme of the road and the railway, a non-intersection channel route scheme is adoptedThe linear grid adaptive direct search algorithm (NOMAD) performs the overall optimization of the line to obtain the final optimized line scheme of the plane and the vertical section.

As shown in fig. 9, a final wiring scheme is obtained, and since the implementation of the above steps is prior art, it is not specifically described.

In summary, the layout method provided in embodiment 1 of the present invention divides the path search problem into the path search of the cross section and the non-cross section, so that the generation of the connection point and the intersection point are independent from each other, the coupling interaction between the connection point and the intersection point is weakened, the optimization problem is simplified, and the intelligent optimization of the interchange passage between the road and the railway is realized.

Example 2:

on the basis of embodiment 1, embodiment 2 of the present invention provides a system for automatically changing an existing road overpass layout method along a railway, including:

the optimization model building module is used for building an optimization model of a road and railway interchange channel line, and comprises: studying decision variables, constraint conditions and optimization functions in the region;

an optimal route obtaining module, configured to splice and integrate the N paths, the M paths, and the H cross section local routes in step S3 to form a plurality of complete routes, and determine an optimal route by using the optimization function as a target function;

The implementation process of each module is described with reference to the foregoing method, and is not described herein again. It should be understood that, the specific implementation process of the above unit module refers to the method content, and the present invention is not described herein in detail, and the division of the above functional module unit is only a division of a logic function, and there may be another division manner in the actual implementation, for example, multiple units or components may be combined or may be integrated into another system, or some features may be omitted, or may not be executed. Meanwhile, the integrated unit can be realized in a hardware form, and can also be realized in a software functional unit form.

Example 3:

on the basis of embodiment 1, an embodiment of the present invention provides a terminal, which includes a processor and a memory, where the memory stores a computer program, and the processor calls the computer program to execute:

S₁: and establishing an optimization model of the road and railway interchange channel line. S₂: dividing the research area into unit grids, and determining local reconstructed roads and local reconstructed roads in the research area according to the existing roads and railwaysThe existing road is connected with the start and end cell set S, E and the left and right cell sets L, R of the railway, and the path search is further decomposed into two sections of non-cross section search and cross section search. S. the₃: and performing line search on the two non-crossed sections by using a DT algorithm. S₄: and (5) iteratively searching to obtain a local line of the cross section. S₅: and integrating the generated two non-crossed sections and the crossed section to form a plurality of complete lines, determining an optimal line by taking the optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme.

For the implementation process of each step, please refer to the specific implementation process of the foregoing method, which is not described herein again.

Example 4:

on the basis of embodiment 1, an embodiment of the present invention provides a readable storage medium, which stores a computer program that is called by a processor to execute: s₁: and establishing an optimization model of the road and railway interchange channel line. S₂: and carrying out unit meshing on the research area, determining a connection starting and ending point cell set S, E of the local reconstructed road and the existing road in the research area and a cell set L, R on the left side and the right side of the railway according to the existing road and the railway, and further decomposing the path search into two non-cross section searches and cross section searches. S₃: and performing line search on the two non-crossed sections by using a DT algorithm. S₄: and (5) iteratively searching to obtain a local line of the cross section. S₅: and integrating the generated two non-crossed sections and the crossed section to form a plurality of complete lines, determining an optimal line by taking the optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme.

It should be understood that in the embodiments of the present invention, the Processor may be a Central Processing Unit (CPU), and the Processor may also be other general purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other Programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The memory may include both read-only memory and random access memory, and provides instructions and data to the processor. The portion of memory may also include non-volatile random access memory. For example, the memory may also store device type information.

The readable storage medium is a computer readable storage medium, which may be an internal storage unit of the controller according to any of the foregoing embodiments, for example, a hard disk or a memory of the controller. The readable storage medium may also be an external storage device of the controller, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like provided on the controller. Further, the readable storage medium may also include both an internal storage unit of the controller and an external storage device. The readable storage medium is used for storing the computer program and other programs and data required by the controller. The readable storage medium may also be used to temporarily store data that has been output or is to be output.

It should be emphasized that the examples described herein are illustrative and not restrictive, and thus the invention is not to be limited to the examples described herein, but rather to other embodiments that may be devised by those skilled in the art based on the teachings herein, and that various modifications, alterations, and substitutions are possible without departing from the spirit and scope of the present invention.

Claims

1. A method for laying overpasses along a railway for automatically changing an existing road is characterized by comprising the following steps: the method comprises the following steps:

step S1: constructing an optimization model of a road and railway interchange channel line, wherein the optimization model comprises the following steps: studying decision variables, constraint conditions and optimization functions in the region;

the path between the cell set S and the cell set L on the same side of the railway and the path between the cell set E and the cell set R on the same side of the railway are two sections of non-crossed section paths; the path between the cell set L and the cell set R is a cross section path;

step S3: performing path search on the two non-crossed sections and the crossed section based on the optimization model;

step S4: splicing and integrating the N paths, the M paths and the H crossed section local lines in the step S3 to form a plurality of complete lines, determining an optimal line by taking the optimization function as a target function, and performing curve fitting on a plane and a vertical section based on the optimal line to obtain a final line scheme;

in the step S2, in the process of dividing the research area into unit grids, the calculation formula of the width of the unit grid is as follows:

width＝2T_min+J_min

in the formula, alpha_maxMaximum allowable turn angle, R, for line design_minIs the minimum curve radius of the road;

the process of performing path search on the cross section to obtain H cross section local lines in step S3 is as follows: iteratively searching local lines between the cell set L and the cell set R, and reserving the local lines meeting the constraint condition, specifically as follows:

taking any cell Li in the cell set L as a center, making a perpendicular line towards the railway and taking the perpendicular line as an angular bisector, and respectively rotating the perpendicular line by 90-A degrees to the left and the right_minObtaining a straight line a and a straight line b, wherein Amin is the minimum crossing angle meeting the standard requirement;

detecting whether the Q local lines meet constraint conditions or not, and if not, rejecting the Q local lines; if yes, generating a plan, a longitudinal section, a bridge and a tunnel circuit scheme of the local circuit;

and iteratively searching all the cells in the cell set L according to the process to generate a local line scheme of H crossed sections.

2. The method of claim 1, wherein: in step S3, the DT algorithm is used in the process of performing path search on two non-intersecting segments based on the optimization model, and the generalized distance value of the cell in the DT algorithm is defined by the optimization function, and the implementation process is as follows:

for the path search process between the set of cells S and the set of cells L:

a-1: taking the cells in the cell set L as the fixed cellsEnd point is determined, and a cell set L [ L ] is selected₁,L₂,...,L_p]One cell L_iAs a fixed end point of the S → L section path, p is the total number of cells in the cell set L;

for the path search process between the set of cells E and the set of cells R:

b-2: in a unit cell R_iAdopting a DT algorithm to search for a fixed end point to obtain a DT value of each cell in the cell set E, and if the DT value of the cell is not positive and infinite, reserving the cell and forming a local path; otherwise, abandoning a local path corresponding to the cell, wherein the cell R is used as the cell_iObtaining a plurality of feasible paths for the fixed end points;

3. The method of claim 2, wherein: in step A-2, cell L is used_iThe process of searching for the DT algorithm for the fixed endpoint to obtain the DT value for each cell in the set S of cells is:

a-2-1: preprocessing a search area, wherein any cell in the search area is fixed to a fixed end point L_iIs using the maximum limit gradient i_maxAnd an allowable line spreading coefficient gamma, satisfying the following formula:

4. The method of claim 3, wherein: the process of constructing the generalized distance map in step A-2-3 is as follows:

a-2-3-1: constructing a neighborhood template, and placing the central position of a neighborhood target on a cell when each cell is scanned;

5. The method of claim 1, wherein: the decision variables in the study area in step S1 are represented as:

plane intersection HIP's (X)_H,Y_H,R_H,L_H0,L_H1)；

Vertical section slope change point VIP's (K)_V,H_V,R_V)；

MBU's (KB) for rebuilding bridges and tunnels on line_S,KB_E,KU_S,KU_E)；

X_Hand Y_HThe abscissa and ordinate of the plane intersection, R_HRadius of intersection corresponding to the intersection of planes, L_H0And L_H1The lengths of the front and rear relief curves corresponding to the plane intersection；K_VAnd H_VMileage and elevation at variable slope points, R_VThe radius of a vertical curve corresponding to the variable slope point; KB_SAnd KB_EKU for the starting and ending mileage of a bridge_SAnd KU_EStarting mileage and ending mileage corresponding to the tunnel; i represents an intersection of the optimized line scheme and a newly-built railway, S represents an initial connection point of the optimized line scheme on an existing road, and E represents an end connection point of the optimized line scheme on the existing road;

F(HPI's,VPI's,MBU's,VCC's)＝min(C_E+C_P+C_R+C_B+C_U)

in the formula, F (HPI's, VPI's, MBU's, VCC's) is the engineering cost on the basis of decision variables, C_E,C_P,C_R,C_B,C_UThe cost of earth and stone engineering, the cost of pavement, the cost of road right, the cost of bridge engineering and the cost of tunnel engineering are respectively;

6. A system based on the method of any one of claims 1-5, characterized by: the method comprises the following steps:

the optimization model building module is used for building an optimization model of a road and railway interchange channel line, and the optimization model comprises: studying decision variables, constraint conditions and optimization functions in the region;

the final line scheme obtaining module is used for carrying out plane and vertical section curve fitting based on the optimal line scheme to obtain a final line scheme;

in the mesh division module, the calculation formula of the width of the unit mesh is as follows:

width＝2T_min+J_min

in the formula, alpha_maxMaximum allowable turn angle for line design，R_minIs the minimum curve radius of the road;

in the cross section path searching module, the path searching is carried out on the cross section to obtain H cross section local lines, wherein the H cross section local lines are as follows: iteratively searching local lines between the cell set L and the cell set R, and reserving the local lines meeting the constraint condition, specifically as follows:

7. A terminal, characterized by: comprising a processor and a memory, the memory storing a computer program that the processor calls to perform: the process steps of any one of claims 1 to 5.

8. A readable storage medium, characterized by: a computer program is stored, which is invoked by a processor to perform: the process steps of any one of claims 1 to 5.