Cable-stayed bridge cable force intelligent optimization method

Abstract

The application discloses a cable-stayed bridge cable force intelligent optimization method, comprising the following steps: 1) defining bridge structure parameters, material characteristics, section characteristics and load parameters; 2) based on the bridge structure parameters, the material characteristics, the section characteristics and the load parameters, a three-dimensional finite element unit model for simulating a main beam, a cable and a main tower is constructed; 3) a target function containing displacement, stress, bending moment and cable force coordination is constructed, and a cable force constraint condition is set; and 4) an intelligent optimization algorithm is used to solve the target function, and optimal cable force is determined. Through finite element modeling technology, scientific multi-target function design and efficient optimization algorithm, the cable-stayed bridge cable force optimization design is intelligentized.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering, specifically to an intelligent optimization design method for cable forces in cable-stayed bridges. Background Technology

[0002] As a typical cable-stayed bridge system, the structural performance of a cable-stayed bridge largely depends on the cable force distribution of the cables.

[0003] Traditional cable-stayed bridge cable force design methods typically rely on empirical formulas and manual calculations. These methods have the following drawbacks: First, they are computationally inefficient, especially for complex bridge structures with long spans and multiple cable groups, where manual calculations are time-consuming. Second, they have a singular optimization objective, often using only one aspect of structural internal forces or alignment as the optimization basis, making it difficult to achieve synergistic optimization of multiple indicators. Third, they lack a systematic constraint handling mechanism, failing to simultaneously consider multiple constraints such as main tower misalignment, main girder stress uniformity, bending moment distribution rationality, and structural stiffness.

[0004] In summary, existing technologies lack a systematic approach for the coordinated optimization of multiple objectives, such as main tower displacement, main beam stress, and bending moment distribution. Summary of the Invention

[0005] The purpose of this invention is to provide a smart optimization method for cable forces in cable-stayed bridges, comprising the following steps:

[0006] 1) Define the bridge structural parameters, material properties, section properties, and load parameters;

[0007] 2) Based on the bridge structural parameters, material properties, cross-sectional properties, and load parameters, a three-dimensional finite element calculation model is constructed to simulate the main beam, stay cables, and main tower;

[0008] 3) Construct an objective function that includes displacement, stress, bending moment, and cable force coordination, and set cable force constraints;

[0009] 4) Use intelligent optimization algorithms to solve the objective function and determine the optimal cable force.

[0010] Furthermore, the bridge structural parameters include the span arrangement Li, the main tower height H_tower, the main tower cross-sectional area A_tower, the number of stay cables n_cables, and the stay cable cross-section A_cables;

[0011] Material properties include the elastic modulus E_deck of the main beam, the elastic modulus E_tower of the main tower, and the elastic modulus E_cable of the stay cables;

[0012] The cross-sectional properties include the main beam cross-sectional area A_deck and moment of inertia I_deck; the main tower cross-sectional area A_tower and moment of inertia I_tower;

[0013] The load parameters include self-weight and secondary dead load.

[0014] Furthermore, the three-dimensional finite element calculation model includes main beam nodes, main tower nodes, and truss elements for simulating stay cables;

[0015] Among them, the main beam nodes include multiple nodes arranged at intervals along the longitudinal direction of the bridge, nodes set at the mid-span, and nodes set at the connection between the main beam and the bridge tower;

[0016] The main tower nodes include multiple nodes arranged in a layered manner along the Z-axis, and nodes located at the connection between the main beam and the bridge tower.

[0017] Furthermore, the boundary conditions of the three-dimensional finite element calculation model include the tower base consolidation constraint, beam end constraint, and main beam-main tower rigid connection constraint.

[0018] The base-consolidation constraint means that all six degrees of freedom of all nodes at the base of the tower are constrained.

[0019] Beam end constraint refers to a beam having a fixed hinge support at one end and a movable hinge support at the other end.

[0020] Furthermore, the value of the cable force satisfies the following constraints:

[0021] Xi≤Fi≤Yi

[0022]

[0023] In the formula, Xi and Yi are the upper and lower limits of the cable force Fi, respectively; max(F_i) is the maximum cable force, min(F_i) is the minimum cable force, and a is the preset threshold.

[0024] Furthermore, the objective function min f_{total} is as follows:

[0025] min f_{total}=min{w1(f_{pos}+f_{neg})+w2f_{cv}+f(g i )}

[0026] In the formula, w1 and w2 are weighting coefficients; f_{pos}, f_{neg}, and f_{cv} are the positive bending moment related terms, negative bending moment related terms, and cable force uniformity related terms, respectively; f(g i ) represents the penalty term for the i-th constraint;

[0027] The terms related to positive bending moment are as follows:

[0028]

[0029] In the formula, M posIt is the set of positive bending moments of all elements of the main beam; σ represents the standard deviation, and μ represents the average value;

[0030] The terms related to negative bending moment are shown below:

[0031]

[0032] In the formula, M neg It is the set of negative bending moments of all elements of the main beam; σ represents the standard deviation, and μ represents the average value;

[0033] The relevant terms for cable tension uniformity are as follows:

[0034]

[0035] In the formula, F is the set of cable forces of all stay cables; σ represents the standard deviation of the cable forces, and μ represents the average value of the cable forces.

[0036] The constraint penalty items are as follows:

[0037] f(g i = C1f_{disp} + C2f_{stress}

[0038] In the formula, C1 is the displacement over-limit penalty coefficient, f_{disp} is the displacement-related term of the main tower, C2 is the stress over-limit penalty coefficient, and f_{stress} is the stress-related term.

[0039] The relevant items for main tower displacement are as follows:

[0040] f disp =f left +f right

[0041] In the formula, f left and f right These are the main tower displacement-related terms for the left and right towers, respectively.

[0042] The relevant items for the main tower displacement of the left tower are as follows:

[0043]

[0044] In the formula, d left D represents the horizontal displacement (mm) of the left tower. max Allowable displacement (mm).

[0045] The relevant items for the main tower displacement of the right tower are as follows:

[0046]

[0047] In the formula, d right The value represents the horizontal displacement (mm) of the right tower.

[0048] The stress-related terms are as follows:

[0049]

[0050] In the formula, σ max For the actual maximum stress (kPa), σ allow This represents the allowable stress (kPa). Both values ​​are absolute values.

[0051] Furthermore, the displacement limit constraints at the top of the tower are as follows:

[0052]

[0053] In the formula, H is the tower height; |δ| is the tower top displacement.

[0054] Furthermore, stress-related terms include steel stress-related terms and concrete stress-related terms.

[0055] Furthermore, when solving the objective function using intelligent optimization algorithms, a negative cable force blocking mechanism is introduced;

[0056] The negative cable force blocking mechanism refers to real-time monitoring of actual cable force, terminating the analysis and returning a maximum penalty value when a negative cable force is detected.

[0057] Furthermore, the intelligent optimization algorithms mentioned in step 4) include, but are not limited to, particle swarm optimization (PSO), genetic algorithm (GA), and differential evolution algorithm.

[0058] The steps for solving the objective function using the PSO optimization algorithm include:

[0059] 4.1) Set parameters, including number of particles, inertia weight, individual cognitive coefficient, group cognitive coefficient, and maximum number of iterations;

[0060] 4.2) The master node distributes particles to the computing cluster;

[0061] 4.3) Each node performs finite element analysis independently.

[0062] 4.4) The master node collects response values ​​and updates the global optimum;

[0063] 4.5) Repeat steps 4.2)-4.4) until the maximum number of iterations is reached, and output the optimal cable force.

[0064] The technical effects of this invention are undeniable. This invention solves the multi-objective optimization problem in cable-stayed bridge design and realizes a paradigm shift from empirical calculation to intelligent optimization in cable-stayed bridge cable force design.

[0065] This invention forms a complete digital design closed loop through parametric modeling, multi-objective optimization functions, intelligent algorithms, and a corresponding constraint system and verification system. It has made breakthrough progress in negative cable force control, bending moment uniformity control, and cable force coordination. Compared with traditional methods, it improves efficiency by more than 60%, reduces main tower displacement, lowers the peak stress of the main beam, makes the positive and negative bending moment values ​​of the main beam more similar, improves cable force uniformity, and significantly enhances the safety and economy of bridge structures. Attached Figure Description

[0066] Figure 1 Optimize decision trees for multiple objectives;

[0067] Figure 2 This forms the core framework of the algorithm.

[0068] Figure 3 This is a bridge layout diagram;

[0069] Figure 4 This is a diagram of the finite element model. Detailed Implementation

[0070] The present invention will be further described below with reference to embodiments, but it should not be construed that the scope of the present invention is limited to the following embodiments. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention should be included within the scope of protection of the present invention.

[0071] Example 1:

[0072] See Figures 1 to 4 A method for intelligent optimization of cable forces in cable-stayed bridges includes the following steps:

[0073] 1) Define the bridge structural parameters, material properties, section properties, and load parameters;

[0074] 2) Based on the bridge structural parameters, material properties, cross-sectional properties, and load parameters, a three-dimensional finite element calculation model is constructed to simulate the main beam, stay cables, and main tower;

[0075] 3) Construct an objective function that includes displacement, stress, bending moment, and cable force coordination, and set cable force constraints;

[0076] 4) Use intelligent optimization algorithms to solve the objective function and determine the optimal cable force.

[0077] Example 2:

[0078] A method for intelligent optimization of cable force in a cable-stayed bridge, with the same technical content as in Example 1, further comprising the following bridge structural parameters: span arrangement Li, main tower height H_tower, main tower cross-sectional area A_tower, number of stay cables n_cables, and stay cable cross-section A_cables;

[0079] Material properties include the elastic modulus E_deck of the main beam, the elastic modulus E_tower of the main tower, and the elastic modulus E_cable of the stay cables;

[0080] The cross-sectional properties include the main beam cross-sectional area A_deck and moment of inertia I_deck; the main tower cross-sectional area A_tower and moment of inertia I_tower;

[0081] The load parameters include self-weight and secondary dead load.

[0082] Example 3:

[0083] A method for intelligent optimization of cable forces in a cable-stayed bridge, with the same technical content as any one of embodiments 1-2, further wherein the three-dimensional finite element calculation model includes main beam nodes, main tower nodes, and truss elements for simulating cable stays;

[0084] Among them, the main beam nodes include multiple nodes arranged at intervals along the longitudinal direction of the bridge, nodes set at the mid-span, and nodes set at the connection between the main beam and the bridge tower;

[0085] The main tower nodes include multiple nodes arranged in a layered manner along the Z-axis, and nodes located at the connection between the main beam and the bridge tower.

[0086] Example 4:

[0087] A method for intelligent optimization of cable forces in cable-stayed bridges, with the same technical content as any one of embodiments 1-3, further wherein the boundary conditions of the three-dimensional finite element calculation model include tower base consolidation constraints, beam end constraints, and main beam-main tower rigid connection constraints;

[0088] The base-consolidation constraint means that all six degrees of freedom of all nodes at the base of the tower are constrained.

[0089] Beam end constraint refers to a beam having a fixed hinge support at one end and a movable hinge support at the other end.

[0090] Example 5:

[0091] A method for intelligent optimization of cable forces in cable-stayed bridges, with technical content identical to any one of embodiments 1-4, further wherein the cable force values ​​satisfy the following constraints:

[0092] Xi≤Fi≤Yi

[0093]

[0094] In the formula, Xi and Yi are the upper and lower limits of the cable force Fi, respectively; max(F_i) is the maximum cable force, min(F_i) is the minimum cable force, and a is the preset threshold.

[0095] Example 6:

[0096] A method for intelligent optimization of cable forces in cable-stayed bridges, with the same technical content as any one of embodiments 1-5, further wherein the objective function min f_{total} is as follows:

[0097] min f_{total}=min{w1(f_{pos}+f_{neg})+w2f_{cv}+f(g i )}

[0098] In the formula, w1 and w2 are weighting coefficients; f_{pos}, f_{neg}, and f_{cv} are the positive bending moment related terms, negative bending moment related terms, and cable force uniformity related terms, respectively; f(g i ) represents the penalty term for the i-th constraint;

[0099] The terms related to positive bending moment are as follows:

[0100]

[0101] In the formula, M pos It is the set of positive bending moments of all elements of the main beam; σ represents the standard deviation, and μ represents the average value;

[0102] The terms related to negative bending moment are shown below:

[0103]

[0104] In the formula, M neg It is the set of negative bending moments of all elements of the main beam; σ represents the standard deviation, and μ represents the average value;

[0105] The relevant terms for cable tension uniformity are as follows:

[0106]

[0107] In the formula, F is the set of cable forces of all stay cables; σ represents the standard deviation of the cable forces, and μ represents the average value of the cable forces.

[0108] The constraint penalty items are as follows:

[0109] f(g i = C1f_{disp} + C2f_{stress}

[0110] In the formula, C1 is the displacement over-limit penalty coefficient, f_{disp} is the displacement-related term of the main tower, C2 is the stress over-limit penalty coefficient, and f_{stress} is the stress-related term.

[0111] The relevant items for main tower displacement are as follows:

[0112] f disp =f left+f right

[0113] In the formula, f left and f right These are the main tower displacement-related terms for the left and right towers, respectively.

[0114] The relevant items for the main tower displacement of the left tower are as follows:

[0115]

[0116] In the formula, d left D represents the horizontal displacement (mm) of the left tower. max Allowable displacement (mm).

[0117] The relevant items for the main tower displacement of the right tower are as follows:

[0118]

[0119] In the formula, d right The value represents the horizontal displacement (mm) of the right tower.

[0120] The stress-related terms are as follows:

[0121]

[0122] In the formula, σ max For the actual maximum stress (kPa), σ allow This represents the allowable stress (kPa). Both values ​​are absolute values.

[0123] Example 7:

[0124] A method for intelligent optimization of cable forces in cable-stayed bridges, with the same technical content as any one of embodiments 1-6, further wherein the tower top displacement limit constraint is as follows:

[0125]

[0126] In the formula, H is the tower height; |δ| is the tower top displacement.

[0127] Example 8:

[0128] A method for intelligent optimization of cable forces in cable-stayed bridges, with the same technical content as any one of embodiments 1-7, further comprising stress-related terms including steel stress-related terms and concrete stress-related terms.

[0129] Example 9:

[0130] A method for intelligent optimization of cable force in cable-stayed bridges, with the same technical content as any one of embodiments 1-8, further wherein a negative cable force blocking mechanism is introduced when solving the objective function using the intelligent optimization algorithm;

[0131] The negative cable force blocking mechanism refers to real-time monitoring of actual cable force, terminating the analysis and returning a maximum penalty value when a negative cable force is detected.

[0132] Example 10:

[0133] A method for intelligent optimization of cable forces in a cable-stayed bridge, with the same technical content as any one of embodiments 1-9, further wherein the intelligent optimization algorithm described in step 4) includes, but is not limited to, particle swarm optimization (PSO) algorithm, genetic algorithm (GA) and differential evolution algorithm;

[0134] The steps for solving the objective function using the PSO optimization algorithm include:

[0135] 4.1) Set parameters, including number of particles, inertia weight, individual cognitive coefficient, group cognitive coefficient, and maximum number of iterations;

[0136] 4.2) The master node distributes particles to the computing cluster;

[0137] 4.3) Each node performs finite element analysis independently.

[0138] 4.4) The master node collects response values ​​and updates the global optimum;

[0139] 4.5) Repeat steps 4.2)-4.4) until the maximum number of iterations is reached, and output the optimal cable force.

[0140] Example 11:

[0141] A method for intelligent optimization of cable forces in cable-stayed bridges, comprising the following steps:

[0142] Parametric modeling

[0143] Define the bridge structural parameters: span arrangement Li, main tower height H_tower, main tower cross-sectional area A_tower, number of stay cables n_cables, and stay cable cross-section A_cables.

[0144] Set material properties: elastic modulus of main beam / tower (E_deck, E_tower), elastic modulus of stay cable (E_cable).

[0145] Calculate the cross-sectional properties: main beam cross-sectional area A_deck, moment of inertia I_deck; main tower cross-sectional area A_tower, moment of inertia I_tower.

[0146] Load parameters: cable force, self-weight, and secondary dead load.

[0147] Finite element model construction

[0148] A three-dimensional beam element model is established to simulate the main beam and main tower. Main beam nodes: nodes are arranged every 10m along the longitudinal direction of the bridge, with nodes set at the mid-span and at the connection between the main beam and the bridge tower; Main tower nodes: arranged in layers along the Z-axis, with one control node every 10m, and nodes set at the connection with the main beam.

[0149] Truss units are used to simulate cable stays, and the connection points between the main beam and the main tower are automatically identified.

[0150] Set boundary conditions

[0151] Tower base fixed: 6-DOF fully constrained. Beam end constraint: Fixed hinge support constraint at one end, and movable hinge support constraint at the other end.

[0152] Establish a rigid connection between the main beam and the main tower (6-DOF coupling constraints).

[0153] Applying loads: self-weight and secondary dead load.

[0154] Cable force application method

[0155] The target cable force is achieved using the initial strain method: the theoretical strain ε=F / (E·A) is calculated based on the target cable force F; a material model with initial strain is created; the cable force is accurately applied through truss elements; and a lower limit protection mechanism for the cable force is set, i.e. force=max(100,cable_forces[i]).

[0156] Multi-objective optimization function design

[0157] Moment balance term: Moment uniformity target

[0158] f_moment=w1(f_{pos}+f_{neg})

[0159]

[0160] Cable force uniformity related items: Cable force uniformity target

[0161] f_cable=w2f_{cv}

[0162]

[0163] Displacement control term: Main tower horizontal displacement penalty function

[0164] f(g1) = C1f_{disp}

[0165] f_{disp}=f_{left}+f_{right}

[0166]

[0167]

[0168] Stress control term: Structural stress over-limit penalty function

[0169] f(g2) = C2f_{stress}

[0170]

[0171] Composition of the overall objective function:

[0172] f_{total}=f_moment+f_cable+f(g1)+f(g2)

[0173] Weighting coefficients: moment balance term w1 = 0.67, cable force uniformity related term w2 = 0.33.

[0174] Penalty coefficients: Displacement exceeding the limit C1 = 10, stress-related term C2 = 10.

[0175] Constraint settings

[0176] Tower top displacement limit: |δ|≤1 / 300 of tower height H

[0177] Negative cable force blocking mechanism: 1. Cable force lower limit constraint: Force F ≥ XikN during optimization; 2. Real-time monitoring: Monitor actual cable force during analysis; 3. Automatic circuit breaking: Terminate analysis and return maximum penalty value when negative cable force is detected.

[0178] Intelligent optimization algorithm

[0179] Particle Swarm Optimization (PSO) algorithm

[0180] Parameter settings:

[0181] Parameters Value Physical meaning Number of particles 50 Breadth of solution space exploration Inertia weight 0.7 Maintain motion inertia Individual cognitive coefficient 1.5 Tendency to move towards historical best position Group cognition coefficient 2.0 Tendency to move towards the global optimal position Maximum number of iterations 100 Calculation termination condition

[0182] Parallel acceleration technology

[0183] Task distribution: The master node distributes particles to the computing cluster.

[0184] Distributed computing: Each node independently performs finite element analysis.

[0185] Result aggregation: The master node collects response values ​​and updates the global optimum.

[0186] Intelligent optimization core

[0187] Dynamic population update: Poles with poor fitness are reinitialized.

[0188] Elite retention strategy: Retain 10% of the optimal solutions in each generation.

[0189] Constraint handling techniques: combining penalty function method with feasibility rules

[0190] Example 12:

[0191] A method for intelligent optimization design of cable forces in cable-stayed bridges, comprising the following steps:

[0192] Initialize bridge parameters and material properties

[0193] Constructing a 3D finite element model in OpenSees

[0194] Define a multi-objective function that includes displacement, stress, bending moment, and cable force coordination.

[0195] Set cable force constraint conditions

[0196] Run the PSO optimization algorithm to solve for the optimal cable force

[0197] Verify the optimization results:

[0198] Main tower displacement ≤ H / 300

[0199] Structural stress: σ≤σ max

[0200] The cable force is positive and evenly distributed.

[0201] The process includes parametric modeling, finite element model construction, multi-objective optimization function design, constraint setting, and intelligent optimization algorithm solution.

[0202] The multi-objective optimization function includes displacement control terms, stress control terms, bending moment balance terms, and cable force coordination terms.

[0203] The initial strain method is used to apply cable force and a negative cable force blocking mechanism is set.

[0204] Set the cable force coordination constraint condition: max(F_i) / min(F_i)≤1.2.

[0205] The optimal cable force combination is solved using the particle swarm optimization algorithm.

[0206] The cable-stayed bridge has a span arrangement of 50m+90m+50m, with the main tower reaching a height of 60m, of which 40m is above the bridge deck and 20m is below. The bridge has a total of 8 cables, with 4 cables anchored to the top of each tower. The cables in the middle span and side spans are symmetrically arranged, as are the cables on the left and right towers. Both the main girder and main towers are constructed of C50 concrete, and the cable stays are made of 1860MPa steel strand. See the bridge layout diagram below. Figure 3 The finite element model diagram is shown below. Figure 4

[0207] Calculation results after optimization using this method:

[0208]

[0209]

[0210] Comparison of optimization effects

[0211] index Optimize the previous value Optimized value Improvement rate Left tower displacement 53mm 16.36mm 69.1％ Maximum stress of main beam 14.9MPa 13.36MPa 10.3％ Coefficient of variation of cable force 13％ 4.55％ 65.0％ Work time 12 hours 3 hours 75％

[0212] The value before optimization is the design value.

[0213] Through engineering examples, this implementation method verifies that it achieves intelligent cable force design for cable-stayed bridges through systematic parameter configuration, innovative finite element modeling technology, scientific multi-objective function design, and efficient optimization algorithms. Breakthroughs have been achieved, particularly in key technical areas such as negative cable force control, displacement-stress synergistic optimization, and cable force uniformity control, providing a new intelligent design solution for bridge engineering.

Claims

1. A method for intelligent optimization of cable forces in cable-stayed bridges, characterized in that, Includes the following steps: Step 1. Define the bridge structural parameters, material properties, section properties, and load parameters; Step 2. Based on the bridge structural parameters, material properties, section properties, and load parameters, construct a three-dimensional finite element calculation model to simulate the main beam, stay cables, and main tower; Step 3. Construct an objective function that includes displacement, stress, bending moment, and cable force coordination, and set cable force constraints; Step 4. Solve the objective function using an intelligent optimization algorithm to determine the optimal cable force; The objective function min f_{total} is shown below: In the formula, w1 and w2 are weighting coefficients; , , These are, respectively, terms related to positive bending moment, terms related to negative bending moment, and terms related to cable force uniformity; This is the penalty term for the i-th constraint; The terms related to positive bending moment are as follows: In the formula, It is the set of positive bending moments of all elements of the main beam; Indicates standard deviation, This represents the average value; The terms related to negative bending moment are shown below: In the formula, It is the set of negative bending moments of all elements of the main beam; Indicates standard deviation, This represents the average value; The relevant terms for cable tension uniformity are as follows: In the formula, F is the set of all the cable forces in the stay cables; The standard deviation of the cable force is represented by the standard deviation of the cable force. This represents the average value of the cable force; The constraint penalty items are as follows: In the formula, C1 is the displacement over-limit penalty coefficient. For the main tower displacement-related terms, C2 is the stress over-limit penalty coefficient. These are stress-related terms; The relevant items for main tower displacement are as follows: In the formula, and These are the main tower displacement-related items for the left and right towers, respectively. The relevant items for the main tower displacement of the left tower are as follows: In the formula, The horizontal displacement of the left tower. To allow for displacement; The relevant items for the main tower displacement of the right tower are as follows: In the formula, This represents the horizontal displacement of the right tower. The stress-related terms are as follows: In the formula, This is the absolute value of the actual maximum stress. This is the absolute value of the allowable stress.

2. The intelligent optimization method for cable-stayed bridge cable forces according to claim 1, characterized in that, Bridge structural parameters include span arrangement Li, main tower height H_tower, main tower cross-sectional area A_tower, number of stay cables n_cables, and stay cable cross-section A_cables; Material properties include the elastic modulus of the main beam E_deck, the elastic modulus of the main tower E_tower, and the elastic modulus of the stay cables E_cable; The cross-sectional properties include the main beam cross-sectional area A_deck and moment of inertia I_deck; the main tower cross-sectional area A_tower and moment of inertia I_tower; The load parameters include self-weight and secondary dead load.

3. The intelligent optimization method for cable-stayed bridge cable forces according to claim 1, characterized in that, The three-dimensional finite element calculation model includes main beam nodes, main tower nodes, and truss elements for simulating stay cables; Among them, the main beam nodes include multiple nodes arranged at intervals along the longitudinal direction of the bridge, nodes set at the mid-span, and nodes set at the connection between the main beam and the bridge tower; The main tower nodes include multiple nodes arranged in a layered manner along the Z-axis, and nodes located at the connection between the main beam and the bridge tower.

4. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, The boundary conditions of the three-dimensional finite element calculation model include the tower base consolidation constraint, beam end constraint, and main beam-main tower rigid connection constraint. The base-consolidation constraint means that all six degrees of freedom of all nodes at the base of the tower are constrained. Beam end constraint refers to a beam having a fixed hinge support at one end and a movable hinge support at the other end.

5. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, In the cable force constraint condition, the value of the cable force satisfies the following constraint, namely: Xi≤ Fi ≤ Yi In the formula, Xi and Yi are the upper and lower limits of the cable force Fi, respectively; max(F_i) is the maximum cable force, and min(F_i) is the minimum cable force. This is a preset threshold.

6. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, The displacement limit constraint at the top of the tower under the cable force constraint conditions is as follows: In the formula, H is the tower height; This represents the displacement at the top of the tower.

7. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, Stress-related items include steel stress-related items and concrete stress-related items.

8. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, When solving the objective function using intelligent optimization algorithms, a negative cable force blocking mechanism is introduced; The negative cable force blocking mechanism refers to real-time monitoring of actual cable force, terminating the analysis and returning a maximum penalty value when a negative cable force is detected.

9. The intelligent optimization method for cable force of a cable-stayed bridge according to claim 1, characterized in that, The intelligent optimization algorithms mentioned in step 4) include, but are not limited to, particle swarm optimization (PSO), genetic algorithm (GA), and differential evolution algorithm. The steps for solving the objective function using the PSO optimization algorithm include: Step 4.

1. Set parameters, including number of particles, inertia weight, individual cognitive coefficient, group cognitive coefficient, and maximum number of iterations; Step 4.

2. The master node distributes particles to the computing cluster; Step 4.

3. Perform finite element analysis independently for each node. Step 4.

4. The master node collects response values ​​and updates the global optimum; Step 4.

5. Repeat steps 4.2-4.4 until the maximum number of iterations is reached, and output the optimal cable force.

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