Mechanical analysis method for unloading process of large-span steel structure

Abstract

The present application relates to steel structure unloading technical field, disclose a kind of large-span steel structure unloading process mechanics analysis method, the method comprises: the design information of target steel structure and unloading temporary support point information are analyzed to topological relationship, and topological connection data and unloading support constraint data are obtained;The unloading process of target steel structure is reconstructed to cause-effect chain, and unloading logic dependency diagram is obtained;State evolution simulation is carried out to target steel structure, and the discrete state point after simulation is continuously smoothed fitting, and state evolution profile is obtained;Mechanical response feature is deconstructed to state evolution profile, and key mechanical state parameter is obtained;The safety performance of target steel structure is evaluated, and safety state score is obtained;Based on safety state score, and in combination with key mechanical state parameter and state evolution profile, unloading process mechanics analysis report is generated;The present application can improve the efficiency of a kind of large-span steel structure unloading process mechanics analysis method.

Description

Technical Field

[0001] This invention relates to the field of steel structure unloading technology, and in particular to a mechanical analysis method for the unloading process of large-span steel structures. Background Technology

[0002] The unloading process of large-span steel structures involves complex force transmission and state evolution of components. Existing mechanical analysis methods have limitations in the topological relationship analysis stage, making it difficult to accurately establish the correlation between steel structure design information and temporary support point information during unloading. This results in insufficient completeness and accuracy of topological connection data and support constraint data, failing to provide a reliable data foundation for subsequent unloading logic deduction. Furthermore, existing methods lack a systematic approach to analyzing the causal relationships during unloading, making it difficult to fully capture the chain effects of support point unloading on the overall structure, leading to deviations in the judgment of unloading sequence and potential impact range.

[0003] Existing technologies are inadequate in simulating state evolution and extracting mechanical parameters. They lack effective methods for continuous and smooth fitting of discrete state points, resulting in state evolution profiles that fail to accurately reflect the dynamic stress changes of steel structures, and insufficient accuracy in identifying key mechanical state parameters. Furthermore, safety performance assessments often rely on single-parameter judgments, lacking comprehensive consideration of multi-dimensional mechanical parameters, leading to insufficient objectivity and comprehensiveness in the assessment results, making it difficult to effectively guide the safe implementation of unloading operations. Therefore, improving the accuracy and efficiency of mechanical analysis during the unloading process of large-span steel structures has become an urgent problem to be solved. Summary of the Invention

[0004] This invention provides a mechanical analysis method for the unloading process of large-span steel structures to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this invention provides a mechanical analysis method for the unloading process of large-span steel structures, comprising: S1. Perform topological relationship analysis on the design information and unloading temporary support point information of the target steel structure to obtain the topological connection data and unloading support constraint data of the target steel structure; S2. Based on the topological connection data and the unloading support constraint data, the causal chain reconstruction of the unloading process of the target steel structure is performed to obtain the unloading logic dependency graph of the target steel structure. S3. Based on the unloading logic dependency graph, perform state evolution simulation on the target steel structure, and continuously and smoothly fit the discrete state points after simulation to obtain the state evolution profile of the target steel structure. S4. Deconstruct the mechanical response characteristics of the state evolution profile to obtain the key mechanical state parameters of the target steel structure; S5. Based on the key mechanical state parameters, conduct a safety performance assessment of the target steel structure to obtain a safety state score for the target steel structure. S6. Based on the safety status score, and combined with the key mechanical state parameters and the state evolution profile, generate a mechanical analysis report on the unloading process of the target steel structure.

[0006] In a preferred embodiment, the step of performing topological relationship analysis on the design information and unloading temporary support point information of the target steel structure to obtain the topological connection data and unloading support constraint data of the target steel structure includes: Obtain architectural appearance data and construction layout plan for the target steel structure; Component connection analysis is performed on the building exterior data to obtain the design information of the target steel structure; Spatial association analysis is performed on the unloading temporary support point information in the construction layout scheme and the design information to obtain a topological relationship description between the unloading temporary support point information and the design information; The topological relationship description is extracted to obtain the topological connection data and unloading support constraint data of the target steel structure.

[0007] In a preferred embodiment, the step of reconstructing the causal chain of the unloading process of the target steel structure based on the topological connection data and the unloading support constraint data to obtain the unloading logic dependency graph of the target steel structure includes: Based on the unloading support constraint data, the component nodes in the topology connection data are constrained and filtered to obtain the constrained component nodes of the component nodes. Starting from the constrained component node, reverse dependency tracing is performed along the component connection path of the constrained component node to construct a temporary support range diagram of the target steel structure. Directed path analysis is performed on the temporary support range map to obtain the connection path depth and connection path direction of the temporary support range map; Based on the connection path depth and the connection path direction, an influence chain deduction is performed on the unloading process of the target steel structure to obtain the potential influence range and unloading sequence of the target steel structure. Based on the potential impact range of the unloading, and with the unloading sequence as the causal guide, an unloading logic dependency graph of the target steel structure is constructed.

[0008] In a preferred embodiment, constructing an unloading logic dependency graph of the target steel structure based on the potential impact range of the unloading and the unloading sequence as the causal guide includes: Convert the affected component nodes in the potential impact range of the unloading into logical state nodes; Based on the time logic of the unloading order, the logical state nodes are bound by time sequence to obtain the causal dependency relationship between the logical state nodes. Based on the causal dependency relationship, directed connection edges are established between the logical state nodes to obtain the initial logical dependency graph of the target steel structure; The initial logical dependency graph is subjected to logical consistency verification, and redundant edges are removed from the verified initial logical dependency graph to obtain the unloading logical dependency graph of the target steel structure.

[0009] In a preferred embodiment, the step of simulating the state evolution of the target steel structure based on the unloading logic dependency graph includes: Based on the initial state description information of the target steel structure, the unloading initial state node in the unloading logic dependency graph is confirmed; Based on the directed edges of the unloading logic dependency graph, the subsequent state nodes of the unloading initial state node are traversed to obtain the subsequent state nodes of the unloading initial state node. Once the subsequent state node is activated, the real-time state description information of the target steel structure is updated. Discretize the real-time state description information to obtain discrete state points of the target steel structure.

[0010] In a preferred embodiment, the step of continuously and smoothly fitting the simulated discrete state points to obtain the state evolution profile of the target steel structure includes: A morphological trend analysis is performed on the simulated discrete state points to obtain the logical association constraints between the discrete state points. Based on the logical association constraints, curve fitting is performed on the discrete state points to obtain the continuous state change curve of the target steel structure; The three-dimensional trajectory of the continuous state change curve is reconstructed to obtain the state evolution profile of the target steel structure.

[0011] In a preferred embodiment, the step of deconstructing the mechanical response characteristics of the state evolution profile to obtain the key mechanical state parameters of the target steel structure includes: Multidimensional feature extraction is performed on the state evolution contour to obtain the contour inflection point features and trend features of the state evolution contour. Gradient parameter analysis is performed on the contour inflection point features and the trend features to obtain the state change rate parameter of the target steel structure. The key mechanical state parameters of the target steel structure are obtained by identifying the principal parameters of the state change rate parameter.

[0012] In a preferred embodiment, the step of assessing the safety performance of the target steel structure based on the key mechanical state parameters to obtain a safety state score for the target steel structure includes: An influence degree analysis is performed on the key mechanical state parameters to obtain the safety performance weights of the key mechanical state parameters; The key mechanical state parameters are normalized to obtain the standardized parameters of the target steel structure. Based on the safety performance weights and the standardized parameters, the safety status score of the target steel structure is calculated.

[0013] In a preferred embodiment, the formula for calculating the security status score is as follows: ; In the formula, This represents the safety status score of the target steel structure. This represents the preset scoring scale constant. This represents the total number of the key mechanical state parameters. Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, This indicates a summation operation.

[0014] In a preferred embodiment, the step of generating a mechanical analysis report of the unloading process of the target steel structure based on the safety status score, combined with the key mechanical state parameters and the state evolution profile, includes: The safety status score is mapped to a preset safety level threshold to determine the stage unloading safety level of the target steel structure. Based on the time information of the stage unloading safety level, the key mechanical state parameters and the state evolution profile are decomposed into stages to obtain the stage parameters and stage profile segments of the target steel structure. The unloading process mechanical analysis report is obtained by associating and integrating the stage parameters, the stage contour segments, and the stage unloading safety level.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention analyzes the topological relationships between the target steel structure design information and the unloading temporary support point information to accurately obtain topological connection data and unloading support constraint data. Combined with causal chain reconstruction, a clear unloading logic dependency graph is formed, laying a solid foundation for subsequent analysis. Simultaneously, state evolution simulation is conducted based on this dependency graph. Through continuous smooth fitting of discrete points, the true state evolution profile is obtained, effectively improving the accuracy and completeness of the state description of the steel structure unloading process.

[0016] 2. This invention deconstructs the mechanical response characteristics of the state evolution profile, accurately identifies key mechanical state parameters, and combines multi-dimensional parameter safety performance assessment and quantitative scoring to ensure the comprehensiveness and objectivity of safety state judgment. Finally, it integrates safety scores, key parameters, and state profiles to generate an analysis report, clearly defining the stage unloading safety level, significantly improving the efficiency and relevance of mechanical analysis, and providing scientific and effective technical support for unloading construction. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a mechanical analysis method for the unloading process of a large-span steel structure, provided in an embodiment of the present invention. The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] This application provides a method for mechanical analysis of the unloading process of a large-span steel structure. The executing entity of this method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the method for mechanical analysis of the unloading process of a large-span steel structure can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms.

[0020] Reference Figure 1 The diagram shown is a flowchart illustrating a mechanical analysis method for the unloading process of a large-span steel structure according to an embodiment of the present invention. In this embodiment, the mechanical analysis method for the unloading process of a large-span steel structure includes: S1. Perform topological relationship analysis on the design information and unloading temporary support point information of the target steel structure to obtain the topological connection data and unloading support constraint data of the target steel structure; In this embodiment of the invention, the step of performing topological relationship analysis on the design information and unloading temporary support point information of the target steel structure to obtain the topological connection data and unloading support constraint data of the target steel structure includes: Obtain architectural appearance data and construction layout plan for the target steel structure; Component connection analysis is performed on the building exterior data to obtain the design information of the target steel structure; Spatial association analysis is performed on the unloading temporary support point information in the construction layout scheme and the design information to obtain a topological relationship description between the unloading temporary support point information and the design information; The topological relationship description is extracted to obtain the topological connection data and unloading support constraint data of the target steel structure.

[0021] Using a laser rangefinder, the external contour, dimensions of each component, and actual installation position of the target steel structure are measured point by point at intervals of 0.5 meters. The specific coordinates of each measurement point in a preset three-dimensional coordinate system are recorded simultaneously. The X-axis corresponds to the length direction of the steel structure, the Y-axis corresponds to the width direction, and the Z-axis corresponds to the height direction. At the same time, the relative positional relationships between components are analyzed, including data such as the spacing between adjacent components and overlapping areas. Meanwhile, key information such as the three-dimensional coordinates of the unloading temporary support points, the model specifications, material parameters, and design load-bearing capacity of the support components are extracted from construction technical documents such as construction organization design and temporary support special plan. By integrating the above measurement data and extracted information, the architectural appearance data and construction layout plan of the target steel structure are obtained.

[0022] Based on the spatial coordinates of each measurement point and the relative positions of components recorded in the building's exterior data, coordinate clustering analysis is used to classify continuously distributed measurement points with a spacing of less than 0.2 meters into the same entity. This identifies various components in the steel structure, such as beams, columns, and nodes. Combined with the material list in the construction technical documents, the specific material of each component is determined. The cross-sectional dimensions of the component are calculated by the coordinate difference of measurement points at different sections of the same component. The length of the component is calculated by measuring the coordinate trajectory along its length. At the same time, based on the coordinate overlap or gap size at the component connection, a gap of less than 0.1 meters with bolt hole coordinate records is identified as a bolted connection, while a gap without gaps and a coordinate segment corresponding to continuous welding marks is identified as a welded connection. The specific connection methods between each component are sorted out, and the attribute information of all components and the connection methods between components are systematically integrated to obtain the design information of the target steel structure.

[0023] Using the three-dimensional spatial coordinates of each component in the design information as the global reference coordinate system, the coordinates of the unloading temporary support points in the construction layout plan are substituted into this coordinate system. By calculating the straight-line distance between the support point coordinates and the coordinates of each component, the specific corresponding position of each unloading temporary support point in the overall steel structure space is determined. If the distance is less than 0.3 meters, it is determined that the support point corresponds to the component. Further analysis is conducted on the contact state between each support point and the surrounding components. If the support point coordinates completely coincide with the component surface coordinates, it is determined to be a direct support relationship. If the distance between the support point and the component is between 0.3 meters and 1 meter and it is on the force transmission path of the component, it is determined to be an indirect influence relationship. At the same time, according to the installation direction of the support point and the design force requirements, the constraint direction of the support point on the corresponding component is determined, that is, the restriction of displacement in the Z-axis direction is a vertical constraint, and the restriction of displacement in the X-axis or Y-axis direction is a horizontal constraint. The above-determined positional relationship, contact relationship, constraint direction and other contents are systematically integrated to obtain the topological relationship description between the unloading temporary support point information and the design information.

[0024] From the topological description, the core elements related to component connections are accurately extracted. Connection nodes are specific spatial locations where component coordinates coincide or gaps are less than 0.1 meters. Connection paths are the coordinate trajectories corresponding to the force transfer between components. Connection strength is determined according to the connection method. These elements are categorized and integrated according to component numbers to form the topological connection data of the target steel structure. At the same time, the core elements related to support constraints are extracted. The constraint objects are specific components less than 0.3 meters away from the support point. The constraint type is the previously defined vertical or horizontal constraint. The constraint range is a spatial area with a radius of 1 meter centered on the support point. These elements are categorized and integrated according to support point numbers to form the unloading support constraint data of the target steel structure.

[0025] The beneficial effects include ensuring the accuracy of building appearance data and construction layout schemes through specific operations such as clear measurement spacing, coordinate system setting, component identification standards, and relationship judgment criteria; comprehensively sorting out component attributes and connection methods through systematic coordinate analysis, attribute matching, and connection method determination to form complete design information; clearly establishing the spatial relationship between unloading temporary support points and design information by leveraging the establishment of a reference coordinate system and clear distance and force path judgment rules, generating detailed topological relationship descriptions; and obtaining complete topological connection data and unloading support constraint data through targeted extraction and classification of core elements. The entire process has clear operational standards and reproducible procedures, effectively ensuring the accuracy and completeness of the data relied upon by subsequent steps such as causal chain reconstruction, and providing a solid and reliable data foundation for the mechanical analysis of the entire large-span steel structure unloading process.

[0026] S2. Based on the topological connection data and the unloading support constraint data, the causal chain reconstruction of the unloading process of the target steel structure is performed to obtain the unloading logic dependency graph of the target steel structure. In this embodiment of the invention, the step of reconstructing the causal chain of the unloading process of the target steel structure based on the topological connection data and the unloading support constraint data to obtain the unloading logic dependency graph of the target steel structure includes: Based on the unloading support constraint data, the component nodes in the topology connection data are constrained and filtered to obtain the constrained component nodes of the component nodes. Starting from the constrained component node, reverse dependency tracing is performed along the component connection path of the constrained component node to construct a temporary support range diagram of the target steel structure. Directed path analysis is performed on the temporary support range map to obtain the connection path depth and connection path direction of the temporary support range map; Based on the connection path depth and the connection path direction, an influence chain deduction is performed on the unloading process of the target steel structure to obtain the potential influence range and unloading sequence of the target steel structure. Based on the potential impact range of the unloading, and with the unloading sequence as the causal guide, an unloading logic dependency graph of the target steel structure is constructed.

[0027] The unloading logic dependency graph of the target steel structure is constructed based on the potential impact range of the unloading and the unloading sequence as the causal guide, including: Convert the affected component nodes in the potential impact range of the unloading into logical state nodes; Based on the time logic of the unloading order, the logical state nodes are bound by time sequence to obtain the causal dependency relationship between the logical state nodes. Based on the causal dependency relationship, directed connection edges are established between the logical state nodes to obtain the initial logical dependency graph of the target steel structure; The initial logical dependency graph is subjected to logical consistency verification, and redundant edges are removed from the verified initial logical dependency graph to obtain the unloading logical dependency graph of the target steel structure.

[0028] Based on the clearly defined constraint object component number, constraint type, and constraint range in the unloading support constraint data, the spatial coordinates and force direction records of each component node in the topology connection data are extracted one by one. The constraint type is either vertical or horizontal constraint, and the constraint range is defined as a spherical spatial region with a radius of 1 meter centered on the three-dimensional coordinates of the corresponding unloading temporary support point. The straight-line distance between the spatial coordinates of the component node and the coordinates of the support point is calculated to determine whether the node is within the constraint range. At the same time, the force direction of the component node is checked to see if it matches the constraint type. If the constraint type is vertical constraint, the force direction of the component node must be vertical and consistent with the height direction of the steel structure. If it is horizontal constraint, the force direction must be horizontal and consistent with the length or width direction of the steel structure. Only component nodes that simultaneously satisfy the condition of having spatial coordinates within the constraint range and force direction matching the constraint type can be identified as constrained component nodes.

[0029] Starting from each constrained component node, reverse dependency tracing is performed based on the component connection node numbers, connection path directions, and connection strength data recorded in the topology connection data. The connection strength must meet the minimum effective connection strength specified in the steel structure design standard, with welded connection strength not less than 200MPa and bolted connection strength not less than 150MPa. Only effective connection paths meeting this strength requirement are traced. The tracing direction is opposite to the normal force transmission direction of the component, i.e., tracing from the constrained component node towards the unloading temporary support point that can provide support force. The node numbers, connection methods, and connection strengths of all traversed components are recorded one by one. These nodes are sorted according to their spatial distribution and connection relationships, and the system is integrated to construct a temporary support range diagram of the target steel structure.

[0030] Each component connection path in the temporary support action range diagram is analyzed one by one. Each path starts from a constrained component node and ends at the unloading temporary support point. Starting from the starting point, each component node along the path is counted sequentially, including both the starting and ending points. The total number of nodes counted is the depth of the connection path. Simultaneously, the transmission direction of each path is clearly defined, which is consistent with the force transmission direction, i.e., from the constrained component node to the unloading temporary support point. The starting point, ending point, depth value, and direction of each path are clearly marked. The analysis results of all paths are compiled into a path parameter table, completing the directed path analysis.

[0031] Influence chain deduction is performed based on the connection path depth and direction. Tracing along the path transmission direction, it is determined whether each component node covered by the path will experience a change in mechanical state after support unloading. The judgment criterion is: based on the component's design stiffness and bearing capacity, if the change in force on the component node exceeds 5% of its design bearing capacity after support unloading, it is determined that a change in mechanical state will occur. All such component nodes are integrated to form the potential unloading influence range. When determining the unloading sequence, first sort by connection path depth from smallest to largest, with component nodes corresponding to shallower depths being unloaded earlier. If multiple component nodes have the same path depth, they are sorted by constraint type priority, with component nodes corresponding to vertical constraints being unloaded first, thus clarifying the complete unloading sequence of the target steel structure.

[0032] Each affected component node within the potential impact range of unloading is converted into a logical state node. Each logical state node must carry the core information of the corresponding affected component node, including a unique component number, the specific force values ​​in the three current directions, constraint status, design bearing capacity, and other key information. The logical state node is identified using a unique format of "component number - status identifier" to ensure that each logical state node corresponds one-to-one with the corresponding affected component node, completely replicating all key status information related to the component and unloading, without any omissions or confusion.

[0033] Based on the time logic reflected in the determined unloading sequence, all logical state nodes are sorted and numbered. The logical state node corresponding to the first component node unloaded in the unloading sequence is numbered 1, and subsequent nodes are numbered sequentially. The rules for determining preceding and succeeding nodes are clearly defined: the node with the smaller number is the preceding node, and the node with the larger number is the succeeding node. The criterion for a preceding node to complete unloading is that the constraint state of the component corresponding to that node is completely released, and the force value is stable. Stable force value requires a change of less than 3% over two consecutive sampling periods. Once a preceding node meets this criterion, it will trigger changes in the mechanical state of the component corresponding to the succeeding node, such as force redistribution and displacement adjustment. This establishes a clear causal dependency between logical state nodes; the preceding node is the direct cause of the state changes of the succeeding node.

[0034] Based on the causal dependencies between logical state nodes, directed edges are drawn between preceding and corresponding subsequent logical state nodes. The direction of these directed edges strictly points from the preceding node to the subsequent node, visually representing the causal transmission relationship. Different line marking methods are used to distinguish the influence of causal dependencies; for example, bolder lines are used for nodes with greater influence. All logical state nodes are arranged according to their spatial distribution and numbering order, and then the corresponding directed edges are connected according to their causal relationships. After system integration, an initial logical dependency diagram of the target steel structure is formed, ensuring that the correspondence between nodes and edges in the diagram is clear and error-free.

[0035] The initial logical dependency graph is checked for logical consistency. Each node's outgoing and incoming edges are traced sequentially from smallest to largest logical state node number to check for closed-loop paths (nodes ultimately pointing to themselves via directed edges). If a circular dependency is found, the node's sequential number is adjusted, shifting the node with the deepest connection in the circular path forward to break the loop. Redundant edges are then removed. For each directed edge, all reachable paths from its predecessor to its successor are analyzed. If deleting the edge allows the predecessor to indirectly point to the successor via one or more other paths, and the causal dependency remains unchanged, the edge is considered redundant. All identified redundant edges are removed, resulting in a logically clear, non-redundant, and loop-free unloading logical dependency graph for the target steel structure.

[0036] The beneficial effects include: ensuring the accuracy of constrained component node identification and avoiding the inclusion of invalid nodes in the analysis by clarifying spatial coordinate comparison methods, force direction matching standards, and connection strength thresholds; focusing on effective connection paths during reverse dependency tracing, and ensuring the integrity and accuracy of the temporary support action range diagram by combining node numbers and detailed records of connection relationships; making connection path parameters clearly traceable by statistically analyzing path depth, defining direction, and organizing parameter tables; refining the mechanical state change judgment criteria and unloading sequence priority rules to make the potential impact range and sequence of unloading more reasonable; ensuring the unique identifier and complete core information of logical state nodes to ensure accurate correspondence with affected component nodes; clear time sequence numbering rules and causal relationship triggering conditions to ensure rigorous and error-free logical dependencies; and ensuring the consistency, simplicity, and effectiveness of the unloading logical dependency diagram by using the directed connection edge identification method and graph structure optimization process. Each step in the entire process has clear operating standards, judgment criteria, and data recording methods, which are fully disclosed and reproducible, providing a logically rigorous and data-reliable core basis for subsequent state evolution simulation, effectively ensuring the orderliness and accuracy of the mechanical analysis of the entire large-span steel structure unloading process.

[0037] S3. Based on the unloading logic dependency graph, perform state evolution simulation on the target steel structure, and continuously and smoothly fit the discrete state points after simulation to obtain the state evolution profile of the target steel structure. In this embodiment of the invention, the step of simulating the state evolution of the target steel structure based on the unloading logic dependency graph includes: Based on the initial state description information of the target steel structure, the unloading initial state node in the unloading logic dependency graph is confirmed; Based on the directed edges of the unloading logic dependency graph, the subsequent state nodes of the unloading initial state node are traversed to obtain the subsequent state nodes of the unloading initial state node. Once the subsequent state node is activated, the real-time state description information of the target steel structure is updated. Discretize the real-time state description information to obtain discrete state points of the target steel structure.

[0038] The step of continuously and smoothly fitting the simulated discrete state points to obtain the state evolution profile of the target steel structure includes: A morphological trend analysis is performed on the simulated discrete state points to obtain the logical association constraints between the discrete state points. Based on the logical association constraints, curve fitting is performed on the discrete state points to obtain the continuous state change curve of the target steel structure; The three-dimensional trajectory of the continuous state change curve is reconstructed to obtain the state evolution profile of the target steel structure.

[0039] The initial state description information of the target steel structure includes core attributes such as the initial stress state of each component, displacement coordinates, constraint type and constraint strength. These attributes are matched one by one with the associated attributes of each logical state node in the unloading logic dependency diagram. Logical state nodes that have not undergone unloading action, whose constraint type is the main load-bearing constraint, whose load-bearing ratio in vertical or horizontal constraints exceeds 70%, and which have not been triggered by other nodes are identified as the initial unloading state nodes.

[0040] Starting from the initial unloading state node, strictly following the direction of the directed edges in the unloading logical dependency graph, first visit the next-level logical state node directly connected to the initial state node, and then use these next-level nodes as new starting points to continue visiting their respective directly connected next-level nodes. This process is repeated until all logical state nodes reachable along the directed edges have been visited. Except for the initial unloading state node, the other visited nodes are the subsequent state nodes of the initial unloading state node.

[0041] The activation condition is set as the component corresponding to the current sequence node completes the unloading action, that is, the constraint state of the component changes from constrained to unconstrained. When this condition is met, the corresponding subsequent state nodes are activated. At this time, based on the component connection relationship and the law of mechanical transmission, the magnitude and direction of the force borne by the component corresponding to the activated node, the displacement offset, and the change of constraint state are calculated. These calculation results are integrated and updated into the real-time state description information of the target steel structure to ensure that the real-time state description information is consistent with the actual state of the component.

[0042] The discretization sampling time interval is set to 10 minutes. Starting from the start of the state evolution simulation, the real-time state description information of the target steel structure is extracted every 10 minutes. Each extraction records the current time point, the stress value of each component, the three-dimensional position coordinates, the constraint state and other core data. The complete state data corresponding to each time point is integrated into an independent data unit, which is a discrete state point of the target steel structure. All discrete state points are sorted and stored in the order of sampling time.

[0043] Arrange all discrete state points in the order of sampling time. For each state parameter of each component, such as force and displacement, analyze the trend of change between adjacent discrete state points and determine whether the trend of change conforms to the mechanical transmission principle of steel structure. For example, the change of force must match the connection path and connection strength of the component, and the change of displacement must be adapted to the magnitude of force and stiffness of the component. Define the change relationship between adjacent state points that conform to this principle as logical association constraints to ensure that the constraint conditions can reflect the inherent law of component state change.

[0044] For each component's individual state parameters, such as vertical force and X-axis displacement, a two-dimensional coordinate system is established with sampling time as the horizontal axis and state parameter value as the vertical axis. All discrete state points corresponding to the parameter are marked in the coordinate system. Based on the determined logical association constraints, a smooth curve that fits all discrete state points and whose slope changes in accordance with the laws of mechanics is drawn, so that the curve can accurately reflect the continuous change of the state parameter over time. The smooth curves corresponding to all state parameters of all components together constitute the continuous state change curve of the target steel structure.

[0045] A three-dimensional coordinate system is established with the X-axis corresponding to the length of the steel structure, the Y-axis corresponding to the width, and the Z-axis corresponding to the height. The three-dimensional displacement coordinates and stress distribution of each component at each time point in the continuous state change curve are correlated and integrated. The overall state of the steel structure at each time point is presented in chronological order, and a three-dimensional graphic is constructed that can intuitively show the dynamic change trajectory of the state of each component and the overall structure of the target steel structure during the entire unloading process. This graphic is the state evolution outline of the target steel structure.

[0046] The beneficial effects are that by establishing clear attribute matching standards, traversal rules, activation conditions, sampling intervals, and constraint bases, the accuracy of initial state node confirmation during unloading, the completeness of subsequent state node traversal, the timeliness of real-time state updates, the standardization of discrete state point sampling, the rationality of logical association constraints, and the smoothness of curve fitting are ensured. Finally, the state evolution contour obtained through three-dimensional trajectory reconstruction can completely and realistically reflect the state change law during the unloading process of the steel structure, providing continuous, accurate, and mechanically sound data support for subsequent mechanical response feature deconstruction, and ensuring the depth and accuracy of mechanical analysis.

[0047] S4. Deconstruct the mechanical response characteristics of the state evolution profile to obtain the key mechanical state parameters of the target steel structure; In this embodiment of the invention, the step of deconstructing the mechanical response characteristics of the state evolution profile to obtain the key mechanical state parameters of the target steel structure includes: Multidimensional feature extraction is performed on the state evolution contour to obtain the contour inflection point features and trend features of the state evolution contour. Gradient parameter analysis is performed on the contour inflection point features and the trend features to obtain the state change rate parameter of the target steel structure. The key mechanical state parameters of the target steel structure are obtained by identifying the principal parameters of the state change rate parameter.

[0048] Multidimensional feature extraction is performed on the state evolution contour. First, the coordinate system of the three-dimensional trajectory is defined: the X-axis corresponds to the length direction of the steel structure, the Y-axis corresponds to the width direction, and the Z-axis corresponds to the height direction. The core analysis dimensions include the vertical, lateral, and longitudinal force data of each component, as well as the displacement coordinate data in the three directions of X, Y, and Z. When calculating the slope of the curve, the difference of the same parameter value at two consecutive time points is taken and divided by the time difference between these two time points to obtain the slope of the curve segment. The position where the absolute value of the slope is greater than 0.5 is set as the contour inflection point. For each inflection point, the corresponding time point, the component number, the specific value of the three-dimensional coordinates, the force values ​​in the three directions, and the constraint state are recorded in detail. All this information of the inflection points is integrated in chronological order to form the contour inflection point feature. The process is divided into segments of 10 minutes each, starting from the beginning of unloading, until the unloading ends. The force and displacement coordinates within each segment are analyzed. In determining the direction of change, an increase in force or displacement value indicates an upward trend, while a decrease indicates a downward trend. The fluctuation amplitude is calculated by subtracting the minimum parameter value from the maximum parameter value within the segment, dividing by the average parameter value within the segment, and then multiplying by 100%. A result less than 5% indicates stability. Simultaneously, the difference between the parameter value at the end of each segment and the parameter value at the beginning is calculated as the total change. These directions and total changes are then categorized and integrated according to component number and parameter type to obtain the trend characteristics of the state evolution profile.

[0049] Gradient parameter analysis is performed on the contour inflection point features and trend features. For contour inflection point features, the same state parameter corresponding to two adjacent inflection points is selected, including vertical force, X-axis displacement, Y-axis displacement, Z-axis displacement, lateral constraint reaction force, and longitudinal constraint reaction force. The parameter value of the previous inflection point is subtracted from the value of the parameter of the later inflection point, and then divided by the difference between the two inflection point time points to obtain the rate of change of the state parameter within the time interval. The corresponding component number and time interval are labeled. For trend features, the same state parameter is selected in each 10-minute time segment. The parameter value at the end of the segment is subtracted from the parameter value at the beginning of the segment, and then divided by a fixed 10-minute time length to obtain the rate of change of the corresponding state parameter within the segment. The corresponding component number, segment number, and parameter type are labeled. The rate of change obtained from all inflection point intervals and time segments is classified and summarized according to parameter type. For example, the rate of change of vertical force of all components is classified into one category, and the rate of change of X-axis displacement of all components is classified into another category. Finally, the state change rate parameter of the target steel structure is obtained.

[0050] For the state change rate parameters, principal parameter identification is performed. First, the total number of occurrences of the change rate parameter corresponding to each state parameter in all inflection point intervals and time segments is counted. That is, the number of inflection point intervals and time segments in which the change rate of the state parameter exists is counted, and the cumulative value is the occurrence frequency of the state parameter. Then, based on the connection nodes and connection paths in the topology connection data, the directly related components of the component to which each state parameter belongs are determined. When the state parameter changes, it is observed whether the corresponding state parameters of its directly related components change. If the number of related components that change exceeds 3, the state parameter is determined to be a high-influence parameter. First, all state parameters are sorted from high to low frequency, and the top 5 state parameters are extracted. Then, these 5 parameters are verified one by one to see if they are high-influence parameters. If there are non-high-influence parameters, they are selected sequentially from the sorted list until 5 state change rate parameters that simultaneously meet the conditions of being among the top 5 in frequency and being high-influence parameters are selected. The original state parameters corresponding to these parameters are determined as the key mechanical state parameters of the target steel structure.

[0051] The beneficial effects are as follows: by clarifying details such as the definition of the three-dimensional coordinate system, parameter types, slope calculation methods, and inflection point judgment criteria, the accuracy and completeness of contour inflection point feature extraction are ensured; by clarifying time segmentation rules, calculation methods for determining the direction of change, and calculation logic for the total amount of change, the extraction process of trend features is made reproducible and the results are detailed; by refining the specific types of the same state parameter, the calculation steps of the rate of change, and the classification and organization methods, the accuracy and systematic nature of the state change rate parameter are ensured; and by clarifying the statistical methods for occurrence frequency, the judgment criteria for related components, and the screening process, the accurate identification of the main parameters is achieved. The resulting key mechanical state parameters can accurately focus on the most critical mechanical influencing factors during the unloading process of the steel structure, providing a targeted, reliable, and logically rigorous core basis for subsequent safety performance assessments, effectively ensuring the scientific nature and accuracy of the safety assessment results. At the same time, the clear operational standards and fully disclosed details throughout the process ensure the feasibility of the technical solution.

[0052] S5. Based on the key mechanical state parameters, conduct a safety performance assessment of the target steel structure to obtain a safety state score for the target steel structure. In this embodiment of the invention, the step of evaluating the safety performance of the target steel structure based on the key mechanical state parameters to obtain a safety state score for the target steel structure includes: An influence degree analysis is performed on the key mechanical state parameters to obtain the safety performance weights of the key mechanical state parameters; The key mechanical state parameters are normalized to obtain the standardized parameters of the target steel structure. Based on the safety performance weights and the standardized parameters, the safety status score of the target steel structure is calculated.

[0053] The formula for calculating the safety status score is as follows: ; In the formula, This represents the safety status score of the target steel structure. This represents the preset scoring scale constant. This represents the total number of the key mechanical state parameters. Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, This indicates a summation operation.

[0054] Referring to the safety performance requirements for large-span steel structures in steel structure design codes, and combining the influence patterns of various mechanical parameters on structural stability and load-bearing capacity observed in engineering practice, an influence level score is assigned to each key mechanical state parameter. The influence level is divided into three levels, corresponding to scores of 3, 2, and 1 point respectively. Parameters that play a decisive role in the overall structural safety receive 3 points, those playing an important role receive 2 points, and those playing a supporting role receive 1 point. The total score of all key mechanical state parameters is calculated, and the score of each parameter is divided by this total to obtain the percentage value corresponding to each key mechanical state parameter. This percentage value is the safety performance weight of the key mechanical state parameter. The sum of the safety performance weights of all key mechanical state parameters is 1.

[0055] We collected measured data of key mechanical state parameters from unloading projects of similar large-span steel structures over the past five years, and selected the maximum and minimum values ​​of each parameter as reference benchmarks. For the original value of each key mechanical state parameter, we subtracted the minimum reference benchmark value of the corresponding parameter from the original value, and then divided the difference by the difference between the maximum and minimum values ​​of the parameter in the reference benchmark. The result is the normalized parameter of the key mechanical state parameter, and the values ​​of all normalized parameters are between 0 and 1.

[0056] A preset scoring scale constant is established, based on the benchmark value for safety performance of large-span steel structures specified in the steel structure design code. Combined with safety assessment data from similar projects over the past decade, this constant is set to a fixed value of 50 to ensure the final safety status score falls within a reasonable assessment range. When calculating the first part of the results, the safety performance weight of each key mechanical state parameter is multiplied by its corresponding standardized parameter. All multiplication results are then summed sequentially to obtain the first part's accumulated result. When calculating the second part of the results, the first part's accumulated result is used as a benchmark. The standardized parameter of each key mechanical state parameter is subtracted from this benchmark to obtain the difference for each parameter. Each difference is squared, and the squared result is multiplied by the safety performance weight of that parameter. All these multiplication results are then summed to obtain a total. The square root of this total is then taken to obtain the second part's calculation result. The first part's accumulated result is added to the second part's calculation result to obtain a comprehensive result. This comprehensive result is then multiplied by the preset scoring scale constant of 50, and the final value is the safety status score of the target steel structure.

[0057] The beneficial effects are as follows: Clearly defined impact levels and scoring rules ensure the rationality and objectivity of safety performance weight allocation, enabling precise quantification of the impact of each key mechanical state parameter; normalization based on historical engineering measured data eliminates dimensional differences between parameters, making each key mechanical state parameter comparable; the scoring calculation considers both the overall level of all key mechanical state parameters weighted by their impact level and the dispersion of each parameter relative to the overall level, combined with a preset scoring scale constant, ensuring that the safety status score comprehensively and accurately reflects the safety performance of the target steel structure during unloading. Furthermore, the entire operation is based on clear standards and calculation logic, and all benchmark data and set values ​​are grounded in engineering practice and standards, ensuring the reproducibility of the technical solution and providing reliable and quantifiable safety performance data support for the generation of subsequent mechanical analysis reports for the unloading process.

[0058] S6. Based on the safety status score, and combined with the key mechanical state parameters and the state evolution profile, generate a mechanical analysis report on the unloading process of the target steel structure.

[0059] In this embodiment of the invention, generating a mechanical analysis report of the unloading process of the target steel structure based on the safety status score, combined with the key mechanical state parameters and the state evolution profile, includes: The safety status score is mapped to a preset safety level threshold to determine the stage unloading safety level of the target steel structure. Based on the time information of the stage unloading safety level, the key mechanical state parameters and the state evolution profile are decomposed into stages to obtain the stage parameters and stage profile segments of the target steel structure. The unloading process mechanical analysis report is obtained by associating and integrating the stage parameters, the stage contour segments, and the stage unloading safety level.

[0060] Based on the mandatory standards for unloading safety of large-span steel structures in the steel structure design code and combined with safety assessment data from similar projects over the past decade, four safety levels are defined: Level 1 (90 points or above), Level 2 (80-89 points), Level 3 (70-79 points), and Level 4 (below 70 points). The unloading process is divided into time segments, with each segment lasting 10 minutes. The safety status score for each segment is extracted and compared with the preset safety level thresholds to determine the safety level for each segment. This level is the stage unloading safety level for the target steel structure, with each stage's safety level corresponding to a specific time segment.

[0061] The start and end times corresponding to the unloading safety level of each stage are extracted. Based on this time range, the key mechanical state parameters are decomposed into stages, and the specific values ​​of all key mechanical state parameters within each time range are selected, including the real-time values ​​and variation amplitudes of each parameter. These data are then organized according to parameter type and time order to obtain the stage parameters of the target steel structure. Simultaneously, using the stage start and end times as time nodes, the three-dimensional trajectory of the state evolution profile is extracted, and three-dimensional trajectory segments are extracted for each time range. These segments must completely present the state change trajectory of each component of the steel structure within the corresponding stage. These trajectory segments are arranged in chronological order to obtain the stage profile segments of the target steel structure.

[0062] The stage parameters and contour segments of each stage are correlated one-to-one with the corresponding unloading safety level in chronological order. Each stage forms a complete data unit containing the safety level, key parameter data, and three-dimensional trajectory segments. All complete data units from all stages are systematically integrated to supplement the overall unloading process with a safety trend analysis. This clarifies the reasons for changes in safety levels at each stage, the impact of key mechanical state parameters on safety levels, and the correlation between trajectory changes and safety levels in the state evolution contour. These contents are organized according to the structure of "overall overview – detailed analysis of each stage – summary and recommendations" to form a mechanical analysis report of the unloading process of the target steel structure. The report must clearly present the safety status, core data, and change patterns of each stage, providing direct reference for unloading construction decisions.

[0063] The beneficial effects include ensuring accurate and consistent determination of the safety level of unloading stages through clear safety level threshold classification standards and scoring comparison methods; decomposing stages based on time information to make the presentation of key mechanical state parameters and state evolution contours more timely and targeted; and comprehensively covering key information such as safety level, core parameters, and state trajectory in the unloading process through systematic integration and structural sorting. The resulting mechanical analysis report of the unloading process is logically clear and data-rich, which not only intuitively reflects the mechanical changes and safety status of the entire unloading process, but also provides clear staged reference for construction personnel. The entire process operation standards are reproducible, ensuring the scientific and practical nature of the report and effectively supporting the safe implementation and optimization of unloading construction.

[0064] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0065] This application embodiment can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is the theory, method, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A mechanical analysis method for the unloading process of a large-span steel structure, characterized in that, The method includes: S1. Perform topological relationship analysis on the design information and unloading temporary support point information of the target steel structure to obtain the topological connection data and unloading support constraint data of the target steel structure; S2. Based on the topological connection data and the unloading support constraint data, the causal chain reconstruction of the unloading process of the target steel structure is performed to obtain the unloading logic dependency graph of the target steel structure. S3. Based on the unloading logic dependency graph, perform state evolution simulation on the target steel structure, and continuously and smoothly fit the discrete state points after simulation to obtain the state evolution profile of the target steel structure. S4. Deconstruct the mechanical response characteristics of the state evolution profile to obtain the key mechanical state parameters of the target steel structure; S5. Based on the key mechanical state parameters, conduct a safety performance assessment of the target steel structure to obtain a safety state score for the target steel structure. S6. Based on the safety status score, and combined with the key mechanical state parameters and the state evolution profile, generate a mechanical analysis report on the unloading process of the target steel structure.

2. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, The topological relationship analysis of the design information and unloading temporary support point information of the target steel structure yields the topological connection data and unloading support constraint data of the target steel structure, including: Obtain architectural appearance data and construction layout plan for the target steel structure; Component connection analysis is performed on the building exterior data to obtain the design information of the target steel structure; Spatial association analysis is performed on the unloading temporary support point information in the construction layout scheme and the design information to obtain a topological relationship description between the unloading temporary support point information and the design information; The topological relationship description is extracted to obtain the topological connection data and unloading support constraint data of the target steel structure.

3. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, Based on the topological connection data and the unloading support constraint data, the causal chain reconstruction of the unloading process of the target steel structure is performed to obtain the unloading logic dependency graph of the target steel structure, including: Based on the unloading support constraint data, the component nodes in the topology connection data are constrained and filtered to obtain the constrained component nodes of the component nodes. Starting from the constrained component node, reverse dependency tracing is performed along the component connection path of the constrained component node to construct a temporary support range diagram of the target steel structure. Directed path analysis is performed on the temporary support range map to obtain the connection path depth and connection path direction of the temporary support range map; Based on the connection path depth and the connection path direction, an influence chain deduction is performed on the unloading process of the target steel structure to obtain the potential influence range and unloading sequence of the target steel structure. Based on the potential impact range of the unloading, and with the unloading sequence as the causal guide, an unloading logic dependency graph of the target steel structure is constructed.

4. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 3, characterized in that, The unloading logic dependency graph of the target steel structure is constructed based on the potential impact range of the unloading and the unloading sequence as the causal guide, including: Convert the affected component nodes in the potential impact range of the unloading into logical state nodes; Based on the time logic of the unloading order, the logical state nodes are bound by time sequence to obtain the causal dependency relationship between the logical state nodes. Based on the causal dependency relationship, directed connection edges are established between the logical state nodes to obtain the initial logical dependency graph of the target steel structure; The initial logical dependency graph is subjected to logical consistency verification, and redundant edges are removed from the verified initial logical dependency graph to obtain the unloading logical dependency graph of the target steel structure.

5. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, The process of simulating the state evolution of the target steel structure based on the unloading logic dependency graph includes: Based on the initial state description information of the target steel structure, the unloading initial state node in the unloading logic dependency graph is confirmed; Based on the directed edges of the unloading logic dependency graph, the subsequent state nodes of the unloading initial state node are traversed to obtain the subsequent state nodes of the unloading initial state node. Once the subsequent state node is activated, the real-time state description information of the target steel structure is updated. Discretize the real-time state description information to obtain discrete state points of the target steel structure.

6. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, The step of continuously and smoothly fitting the simulated discrete state points to obtain the state evolution profile of the target steel structure includes: A morphological trend analysis is performed on the simulated discrete state points to obtain the logical association constraints between the discrete state points. Based on the logical association constraints, curve fitting is performed on the discrete state points to obtain the continuous state change curve of the target steel structure; The three-dimensional trajectory of the continuous state change curve is reconstructed to obtain the state evolution profile of the target steel structure.

7. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, The mechanical response feature deconstruction of the state evolution profile yields the key mechanical state parameters of the target steel structure, including: Multidimensional feature extraction is performed on the state evolution contour to obtain the contour inflection point features and trend features of the state evolution contour. Gradient parameter analysis is performed on the contour inflection point features and the trend features to obtain the state change rate parameter of the target steel structure. The key mechanical state parameters of the target steel structure are obtained by identifying the principal parameters of the state change rate parameter.

8. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, The safety performance assessment of the target steel structure based on the key mechanical state parameters, to obtain a safety state score for the target steel structure, includes: An influence degree analysis is performed on the key mechanical state parameters to obtain the safety performance weights of the key mechanical state parameters; The key mechanical state parameters are normalized to obtain the standardized parameters of the target steel structure. Based on the safety performance weights and the standardized parameters, the safety status score of the target steel structure is calculated.

9. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 8, characterized in that, The formula for calculating the safety status score is as follows: ； In the formula, This represents the safety status score of the target steel structure. This represents the preset scoring scale constant. This represents the total number of the key mechanical state parameters. Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, Indicates the first Safety performance weights of key mechanical state parameters Indicates the first Normalized parameters of key mechanical state parameters, This indicates a summation operation.

10. The mechanical analysis method for the unloading process of a large-span steel structure as described in claim 1, characterized in that, Based on the safety status score, and combined with the key mechanical state parameters and the state evolution profile, a mechanical analysis report on the unloading process of the target steel structure is generated, including: The safety status score is mapped to a preset safety level threshold to determine the stage unloading safety level of the target steel structure. Based on the time information of the stage unloading safety level, the key mechanical state parameters and the state evolution profile are decomposed into stages to obtain the stage parameters and stage profile segments of the target steel structure. The unloading process mechanical analysis report is obtained by associating and integrating the stage parameters, the stage contour segments, and the stage unloading safety level.

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