1058 results about "Arch bridge" patented technology

The invention relates to the technical field of construction control, and particularly discloses a method and a system for dynamically regulating and controlling the installation precision of an inclined-span steel box arch bridge based on machine learning. Wherein the real-time data comprises real-time stress of the arch rib, real-time deformation of the arch rib, real-time environment wind speed and real-time hoisting parameters; constructing a prediction model capable of analyzing the coupling effect of the wind load and the hoisting unbalance load based on a large amount of historical construction data; inputting real-time data into the prediction model to obtain a real-time coupling effect analysis result; outputting a hoisting sequence optimization instruction based on the decision engine, the coupling effect analysis result and a preset mechanical constraint condition of the obliquely-spanning steel box arch bridge; based on the deviation between the real-time deformation amount of the arch rib and a preset installation precision threshold value, a cable force grading adjustment scheme is generated; construction efficiency of the inclined-span steel box arch bridge is effectively improved, construction safety and installation precision are guaranteed, and stability and reliability of the bridge structure are guaranteed.

The invention relates to the technical field of image analysis, in particular to a concrete arch bridge crack semantic segmentation method based on multispectral imaging, and the method comprises the following steps: collecting a multi-period multispectral image through an unmanned aerial vehicle, segmenting a crack region through a K mean value of the multispectral image, extracting a multiband spectral vector sequence, and carrying out the sliding normalization to generate a principal axis spectral vector; and calculating a spectral vector included angle and a change rate mark jump point, screening boundary points by combining direction consistency and gradient scoring, extracting spectral lines Z-score standardization by time sequence alignment, evaluating discrete fluctuation, correcting an abnormal output concrete arch bridge crack binary segmentation map. According to the method, the reflection spectrum sequence is constructed through the multi-period multi-spectral image, the crack recognition precision is improved by combining the main shaft features and the sliding window, the texture interference is eliminated by using the spectral vector included angle change and the gradient score, the standardized spectral line time sequence model is generated, the boundary positioning accuracy is enhanced, the noise interference is reduced, and the long-term monitoring of the structural damage is supported.

The concrete-filled steel tube arch bridge detection system and method based on multi-modal fusion and quantum optimization are used for bridge structure health monitoring. The system comprises a multi-modal data acquisition module, a quantum optimization data fusion module, a defect self-growth simulation damage prediction module, a low-power-consumption intelligent sensor network and a quantum safety remote monitoring module. The multi-modal data acquisition module is fused with an ultrasonic radar, a millimeter wave radar, a hyperspectral image, a LiDAR and a wireless sensor, and bridge surface and internal damage detection is realized; the data weight is dynamically adjusted by adopting a quantum optimization algorithm, and the fusion precision is improved; in combination with a graph neural network and deformable grid calculation, crack propagation and fatigue damage development are predicted, the power consumption of the sensor is reduced through an energy collection technology, and the safety of remote monitoring data is ensured by adopting a quantum safety remote monitoring module. Compared with the prior art, the method improves the detection precision, prediction capability and data safety, and is suitable for health monitoring of various bridges and infrastructures.

The invention discloses an intelligent and efficient detection method for concrete-filled steel tube arch bridge arch rib void. The method comprises the following steps: 1, detecting a full bridge arch rib through laser scanning, obtaining three-dimensional point cloud data, identifying a suspected void area, and generating a bridge three-dimensional model; 2, detecting a full-bridge arch rib through infrared thermal imaging, recording a temperature distribution diagram, identifying a temperature abnormal region, and confirming a suspected void region; 3, echo signal characteristics of the suspected void area are detected through ultrasonic waves, and the specific position, depth and range of void are determined; 4, carrying out fusion analysis on laser scanning, infrared thermal imaging and ultrasonic detection data to generate a three-dimensional void distribution model, and generating a comprehensive detection report in combination with multi-source data; and 5, the arch bridge is monitored in real time, trend analysis and prediction are performed in combination with historical data, and a void expansion early warning mechanism is formed. According to the method, the void position, depth and range of the arch rib can be detected in a high-precision and non-destructive manner, and a reliable guarantee is provided for bridge safety.

The invention relates to the technical field of arch bridge monitoring, and particularly discloses a deformed steel arch bridge health monitoring and early warning system based on multi-source data fusion, which comprises a data acquisition module, a data preprocessing module, a multi-source data fusion module, an anomaly detection and mode recognition module and a health assessment and early warning module, a visual detection and image analysis module and a risk prediction and decision support module; by adopting the adaptive sampling method, the sampling frequency can be dynamically adjusted according to the dynamic change of the bridge, the load state and the importance of the sensor, so that the sampling frequency is reduced when the bridge is in a stable state, and the collection of redundant data is reduced; the redundant data generated when the data acquisition frequency is too high is reduced through self-adaptive sampling, so that the requirement for the storage space and the bandwidth requirement for data transmission are reduced, and the calculation efficiency is improved.

The invention provides an anomaly detection method and system based on Bi-LSTM and ST-GCN, and the method comprises the steps: constructing a space-time joint modeling frame for bridge health monitoring through the staged fusion of a bidirectional long-short time memory neural network (Bi-LSTM) and a space-time diagram convolutional neural network (ST-GCN) based on a point-line-plane three-stage detection mechanism for a tied arch bridge; the method comprises the following steps: extracting time sequence characteristics of a cable force meter through Bi-LSTM, identifying a single-sensor hardware fault, separating shared characteristics and sensor private characteristics from multi-sensor time sequence data, and enhancing sensor identity distinction degree and inhibiting interference factors such as temperature through decoupling comparison loss; the sensor private features are used as node features in an ST-GCN neural network, spatial positions among different sensors are identified by adopting a time attention mechanism through ST-GCN, spatial topological association and long-term time sequence dependence among the sensors are captured, and connection probability anomaly under a static adjacency relation is analyzed; and finally, the identified spatial position is analyzed and self-adaptive early warning is carried out, and a multi-node collaborative abnormal region is positioned through a connected domain algorithm, so that local damage and global abnormality are accurately positioned. The function of monitoring whether the bridge structure is damaged or not is achieved. Compared with a traditional machine learning database, more experimental parameters and a larger experimental data set are selected; the defect of low prediction precision of traditional machine learning is avoided, and the method has very high accuracy and reliability.

The invention relates to the field of concrete-filled steel tube structure mechanical property tests, in particular to a concrete-filled steel tube arch rib member long-term load and corrosion intelligent test device and method. The test device comprises: a corrosion tank covering the outside of a concrete-filled steel tube arch rib test piece and capable of being filled with or sprayed with a corrosive liquid; the load applying device comprises a plurality of load applying units, and each unit is used for applying long-term load to the concrete-filled steel tube arch rib test piece; the load applying unit comprises a screw rod, a nut, a loading end plate, a loading block and a force transmission block; the loading block penetrates through the corrosion tank and is tightly attached to the test piece, the force transmission block is located below the loading block and is tightly attached to the corrosion tank, and the multiple screws penetrate through the corrosion tank, so that the loading block can apply force to the concrete filled steel tube arch rib test piece; the sensor feeds back data to the data acquisition terminal in real time for processing, and the corrosion process is accurately controlled. According to the invention, the stress characteristics of the concrete-filled steel tube arch bridge under long-term load and corrosion effects can be simulated based on an intelligent technology.

The invention discloses a digital twinborn monitoring method for a self-evolution concrete-filled steel tube arch bridge, and the method comprises the steps: collecting multi-source monitoring data through deploying a multi-mode sensor at a key component of a bridge, and constructing an initial structure topological graph; and dynamic evolution and anomaly detection of the structure topology are realized by using a graph neural network and a Transform structure. Intelligent recognition and fault diagnosis of a structure state are realized by constructing a multi-physical field five-dimensional tensor and a health knowledge graph. And finally, generating and optimizing a structure alternative scheme by adopting a graph generative adversarial network and a genetic algorithm, verifying the performance of the scheme through finite element simulation, and realizing intelligence of bridge health monitoring and maintenance decision making. According to the method, real-time sensing, dynamic modeling and intelligent diagnosis of the structural state of the concrete-filled steel tube arch bridge are achieved by fusing multi-modal sensor data, multi-physical field coupling analysis, graph neural network modeling and an intelligent reasoning mechanism, the real-time performance and accuracy of monitoring are improved, and a scientific basis is provided for structural optimization design of the bridge.

The invention provides an arch bridge cable force adjusting method and device, a medium and a program product, and relates to the technical field of arch bridge cable force adjusting.The method comprises the steps that by establishing an arch bridge parameterization finite element model, specific unit force is applied to all suspenders to construct a first influence matrix; singular value decomposition is carried out on the first influence matrix, the first k suspenders with the total energy contribution rate exceeding a first preset value are extracted, and the sensitivity of the suspenders to the global suspender cable force is calculated; calculating an importance index in combination with sensitivity and suspender cable force deviation, and screening the first n important key suspenders to construct a second influence matrix; an adjusted vector is obtained based on the difference value of the second influence matrix and the target influence matrix, and the cable force adjustment amount of the key suspender is solved; the key suspender cable force is sequentially adjusted according to the importance sequence. According to the method, the key suspender is accurately identified through matrix decomposition and sensitivity analysis, the adjustment amount is quantified, interaction is considered, full suspender adjustment is avoided, the construction cost is remarkably reduced, and the cable force adjustment efficiency and accuracy are improved.

The invention relates to the technical field of bridge construction, in particular to an arch bridge construction counterweight optimization method and system based on stress monitoring. The method comprises the following steps: arranging a plurality of stress sensors at different parts of an arch bridge, and collecting stress monitoring data; performing data preprocessing operation and feature extraction operation on the stress monitoring data; inputting the features, the construction state parameters and the structure parameters into a machine learning model to obtain an arch bridge multi-section stress trend; generating an arch bridge construction counterweight optimization scheme by adopting a non-dominated sorting genetic algorithm; dynamically adjusting the counterweight optimization scheme according to stress monitoring data and the multi-section stress trend of the arch bridge; therefore, accurate and scientific optimization of the counterweight scheme in the arch bridge construction process is realized.

The invention provides a method for monitoring and controlling cable-stayed buckling construction of a concrete-filled steel tube arch bridge based on a digital twin system, and the method comprises the steps: collecting the monitoring data, such as wind speed and wind direction, arch rib stress displacement, tower bottom stress, tower deviation and cable force, through a sensor; establishing a concrete filled steel tube arch bridge construction digital twinning system based on a three-dimensional model, real-time monitoring, data analysis and a visual platform; time sequence data is decomposed into different frequency components through variational mode decomposition (VMD), a bridge construction stage prediction model is established through a long short-term memory network (LSTM), and real-time accurate prediction of the construction progress and state is achieved. And secondly, based on the prediction model and on-site real-time monitoring conditions, an intelligent load adjustment construction control method based on a digital twin system is provided, and high-precision control over automatic load adjustment of cable hoisting and real-time rectification of tower displacement is achieved. The problems that in a traditional monitoring and control method, early warning is not timely, the assembling precision is insufficient, and the arch axis shape control difficulty is large are solved.

This method is applicable to the technical field of bridge construction and provides a method for real-time monitoring and evaluation of the force-bearing state during the casting process of a steel-pipe concrete arch bridge. The solution involves identifying environmental background points in the RGB three-dimensional matrix for the entire bridge within the range between the maximum and minimum RGB values ​​in the local RGB three-dimensional matrix for the steel pipe, representing environmental background temperature points in the temperature information matrix, and identifying concrete pouring points based on whether the unit matrix condition for the temperature of the steel dome pipe is met. The system also obtains the horizontal axis of the pixel at the center of the poured liquid surface in the left and right half arches in a Cartesian coordinate system, divides the entire arch rib to be poured into 2n equal parts, and calculates the cross-sectional displacement response of each structure based on the cross-sectional displacement caused by the load action of each segment. This allows for real-time, efficient, and accurate observation of the difference in concrete liquid surface level on both sides, allowing for the structural response during pouring to be determined and reducing the construction risk of arch bridges.

The invention discloses a stiff skeleton arch bridge arching process optimization method and system considering multiple objectives, and belongs to the technical field of bridge construction.The method includes the steps that a stiff skeleton arch bridge main arch ring finite element model is established, design variables and optimization objectives are analyzed and determined, and a multi-objective optimization model is established; minimization of instantaneous stress and permanent stress of a main arch ring of the stiff skeleton arch bridge and minimization of vertical deformation of a vault are used as objective functions, the length of a working face is used as a design variable, and constraint conditions are set. After an initial pouring scheme is determined based on an actual construction scheme, an optimization scheme is solved by adopting an NSGA-II algorithm. And further constructing quantitative evaluation indexes including a comprehensive stability coefficient and a stability coefficient variance, constructing a comprehensive evaluation index based on the quantitative evaluation indexes, and finally determining an optimal pouring scheme. The arch forming quality and the structural safety of the arch bridge can be effectively improved, the construction scheme is optimized, the construction cost is reduced, and important engineering application value is achieved.

The invention relates to a concrete filled steel tube arch bridge node comprehensive evaluation and green design method and an optimization system. The method comprises the steps of node parameter input, mechanical property evaluation, durability evaluation, construction process difficulty evaluation, material suitability evaluation and comprehensive score calculation. The system integrates a comprehensive evaluation module, a construction process simulation module, a self-repairing module and an intelligent monitoring module, and provides omnibearing support. A design method based on green construction and an extreme environment adaptability analysis method are also covered, material selection is optimized through life cycle analysis, and the implementability and long-term stability of node design are ensured. And an artificial intelligence technology is introduced to realize weight adaptive adjustment and optimization suggestion generation, so that the intelligence and flexibility of evaluation are improved. According to the method, node design and construction can be effectively guided, resource allocation is optimized, construction risks are reduced, the service life of nodes is prolonged, and the requirements of green construction and sustainable development are met.

The invention discloses a positioning and adjusting device for hoisting an arch rib of a steel pipe arch bridge, and belongs to the field of positioning devices. The device mainly comprises a positioning and adjusting device, the positioning and adjusting device comprises a left-right fine adjustment system, an up-down fine adjustment system is fixedly installed on the left-right fine adjustment system, and a steel pipe arch bridge arch rib bearing and fixing device is fixedly installed on the up-down fine adjustment system; according to the positioning and adjusting device for hoisting the arch rib of the steel pipe arch bridge, the safety risk during hoisting of the arch rib of the steel pipe arch bridge can be greatly reduced, and the offset precision of the arch rib during hoisting can be improved; meanwhile, the device is specifically divided into three systems, namely, a left-right fine adjustment system, an up-down fine adjustment system and a steel pipe arch bridge arch rib bearing and fixing device, and accurate deviation of the arch bridge can be achieved through close fit with an external lifting crane.

The utility model relates to a mounting type arch bridge main arch ring maintenance operation platform which comprises a walking system, a suspension system, a platform system and a platform lifting system. The walking system is provided with walking trolleys on the top faces of the two sides of the main arch ring respectively and can walk along rails arranged on the main arch ring, the suspension system is suspended on the two walking trolleys through a cantilever beam, platforms on the two sides of the platform system are located on the two sides of the main arch ring respectively, a lower platform is located below the main arch ring, and a winch of the lifting system is arranged on the suspension system. And the side platform and the lower platform are connected through a traction rope. The main arch ring maintenance platform is directly hung on a main arch ring and walks along the main arch ring, bridge floor traffic can be prevented from being affected, and constructors can carry out all-directional maintenance operation on the main arch ring on the platform.

The invention discloses a method for manufacturing an arched girder combined section of a super-large-section steel box arch bridge suitable for highway transportation. Comprising a manufacturing process method of an oversized arch foot steel straining beam rod piece of a parallelogram structure and an oversized arch foot steel arch rib rod piece of an octagonal structure and a process method for controlling the assembly size and the linear shape of an overall space structure of an arch foot steel straining beam and an arch foot steel arch rib. The arch foot steel straining beams of the parallelogram box type structures and the octagonal arch foot arch ribs are integrally manufactured, and the arch foot arch ribs and the arch foot straining beams are connected in a welded mode. According to the method, the complex structural characteristics of octagonal arch springing arch ribs and parallelogram irregular arch springing straining beams of the steel box arch bridge arch beam combination section are combined, the method that the plate units are manufactured firstly and then the box body is assembled is adopted, the tailor-welding size of each plate unit is controlled, and control over welding deformation and the overall size of the subsequent box body is facilitated; an integral horizontal pre-splicing method is adopted, and a matching piece welding method is adopted, so that the aim of controlling the spatial relationship between the arch springing, the arch rib and the straining beam is achieved.

The invention discloses a large-span tied arch bridge steel box arch rib construction control method. The method comprises the steps that a large-span tied arch bridge steel box arch rib section three-dimensional model is established, and arch rib sections are numbered in sequence; performing all-weather continuous monitoring on the arch rib section temperature data room by using mathematical statistics and a comparative analysis method to obtain monitoring data; analyzing an influence rule of natural parameters, steel box arch rib structure attributes and construction parameters on the space time-varying non-uniform temperature field by adopting a heat exchange theory of a bridge structure and an external environment and a bridge structure thermal analysis theory according to the monitoring data and the three-dimensional model; and according to the influence rule, the expected folding time and the position size of a folding opening are determined, the position size of the folding opening is adjusted based on a folding opening adjusting device, and the arch rib section folding construction operation is completed within the expected time. The expected folding time and the folding opening position size are accurately determined, and the construction precision and efficiency are effectively improved.

The invention discloses a comprehensive evaluation method for the health state of concrete filled steel tubes. According to the method, a multilevel evaluation index system for the health state of the concrete-filled steel tube structure is constructed, and factors influencing the health of the structure are divided into a plurality of key indexes including the ultimate bearing capacity, the overall stability performance, the anti-seismic performance and the like. The method comprises the following steps: firstly, quantifying each index by using a membership function in fuzzy mathematics, and constructing a membership matrix; secondly, determining the weight of each index according to the influence of each index on the whole bridge; then, the health state of the concrete filled steel tube is evaluated through the fuzzy comprehensive evaluation model, the structure health level is generated, an accurate health state evaluation result is provided, and the method is suitable for health monitoring and evaluation of complex concrete filled steel tube structures such as bridges, tunnels and high-rise buildings. The method has the advantages of being high in evaluation precision, wide in application range and easy and convenient to operate, and a scientific basis is provided for safety management and maintenance decision making of the concrete-filled steel tube structure.

According to the method for designing the reasonable arch axis of the large-span arch bridge based on the hybrid calculation algorithm and the self-adaptive load distribution, an analytic equation method, a curve fitting method and an intelligent optimization algorithm are combined, and by selecting the initial arch axis, introducing a dynamic load distribution model and applying a genetic algorithm and a particle swarm optimization algorithm, the reasonable arch axis of the large-span arch bridge is designed. Global and local optimization is carried out, and the optimal shape and load distribution of the arch axis are ensured. And finally outputting design parameters, such as a control point, a bending moment, thrust and the like. According to the method, the design precision, flexibility and safety can be effectively improved, the material utilization rate is optimized, the cost is reduced, and the method is particularly suitable for design of large-span bridges and has high practical value.

The invention discloses a supporting device for reinforcing an arch bridge bottom die, and belongs to the technical field of arch bridge bottom dies. The supporting device comprises a base, first demolding plates are symmetrically arranged on the two sides of the upper end of the base, second demolding plates are arranged at the ends, away from each other, of the two first demolding plates, a first splicing plate is clamped between the first demolding plate and the second demolding plate on the same side, and a second splicing plate is clamped between the two first demolding plates; a lifting radian adjusting mechanism is arranged at the upper end of the base, and the heights and the radians of the first demolding plate and the second demolding plate are adjusted through the lifting radian adjusting mechanism; the gaps between the first demolding plates and the second demolding plates and the gap between the two first demolding plates are filled through the first splicing plates and the second splicing plates correspondingly; the height and radian of the supporting device can be flexibly and accurately adjusted, and the reinforcing requirements of arch bridge bottom dies of various complex shapes and sizes can be met.

The invention discloses a high-efficiency cable intelligent control method and system for a steel box truss arch bridge, and the method comprises the steps: 101, sampling the tensioning force of all cables according to a preset sampling period, generating the tension time sequence data of all cables, dividing the tension time sequence data of each cable into a plurality of main windows, each main window is divided into a plurality of sub-windows; 102, sub-windows in each main window are divided into static state sub-windows and dynamic state sub-windows, and the main windows with the number of the dynamic state sub-windows exceeding a dynamic number threshold value serve as dynamic section main windows; and step 103, judging whether each dynamic state sub-window in the dynamic section main window has cable drift or not, and if the cable drift occurs, adjusting the cable.

The invention relates to the technical field of bridge construction, and provides a broken geological slope belt cable crane main anchorage and an anchor cable construction method.The main anchorage is arranged on slope zones on the two sides of an arch bridge and comprises an anchor beam, a plurality of anchor cables and a plurality of anchorage piers cast-in-place on a slope excavation platform, and the backs of the anchorage piers are obliquely arranged; each anchor beam is arranged between every two adjacent anchor piers, one end of each anchor cable is anchored in deep bed rock of the broken geological slope zone, and the other end of each anchor cable is connected with the corresponding anchor pier; aiming at a mountain slope zone with broken geology, the main anchorage adopts a pre-stress anti-pulling structure, so that large-volume excavation of a gravity type anchorage on a rock mass is avoided, the anchor cable can directly penetrate through a poor stratum by adopting a drilling sleeve follow-up technology, the hole forming difficulty is reduced, and the construction efficiency is improved. The effect of reinforcing the mountain of the broken layer on the back face of the main anchorage is further achieved by adopting a sealing structure for sealing pressure grouting, the integrity and the stress performance of the broken layer are improved, and the situation that the uplift resistance of the main anchorage is affected due to extrusion deformation of the mountain is prevented.

The invention provides a tower-free full-arch-width self-adaptive transverse moving cable crane system and method.The system comprises an anchoring foundation and a main cable transverse moving system, the main cable transverse moving system is connected with the anchoring foundation, and the anchoring foundation is arranged on a concrete anchor; the main cable transverse moving system comprises a steel anchor beam, a fixed base, a sliding cable rotating saddle and a dragging system, the two ends of the steel anchor beam are fixedly connected with the fixed base, the steel anchor beam is sleeved with the sliding cable rotating saddle, the sliding cable rotating saddle and the steel anchor beam are in sliding connection, and after sliding to a target position, the sliding cable rotating saddle and the steel anchor beam are connected through a limiting device; the lower end of the fixed base is connected with the anchoring foundation, and the dragging system is arranged below the two ends of the steel anchor beam and connected with the sliding cable rotating saddle. The anchoring foundation is adopted to completely replace a traditional tower structure, the occupied area of the foundation is greatly reduced, and steep terrain limitation is broken through; through the synergistic effect of the sliding cable rotating saddle and the rotating clamping plate, self-adaptive transverse position adjustment and structural stability control of a single system within the full-width range of the arch bridge are achieved.

The invention provides an adjustable universal profile steel arch frame adjusting device and an adjusting method thereof, a steel arch frame is connected through a plurality of standard sections to form a steel arch bridge structure, the tops of the adjacent standard sections are connected through an adjusting screw rod, the bottoms of the adjacent standard sections are hinged, the standard sections are provided with speed reducing motors, and the speed reducing motors are connected with the adjusting screw rod. The gear motor drives the nut sleeve of the adjusting screw rod to rotate, and the camber of the whole steel arch can be adjusted by changing the distance between the tops of the adjacent standard sections driven by the nut sleeve. And the adjustment is not limited by the problems of complexity and accuracy of manual adjustment, so that the engineering efficiency and the engineering quality are remarkably improved, the installation cost is reduced, and the safety and durability of a bridge structure are enhanced.

According to the durability evaluation method for the arch rib of the concrete-filled steel tube arch bridge considering the toughness, comprehensive evaluation on the durability of the arch rib is realized by combining a sensor network, nondestructive testing, a toughness evaluation test, environmental monitoring and an artificial intelligence analysis technology. A vibrating wire strain gauge sensor is arranged on an arch rib to collect strain data in real time; detecting internal defects and temperature abnormity by utilizing ultrasonic detection and infrared thermal imaging technologies; performing an impact test through an impact testing machine, and evaluating the toughness of the arch rib; a weather station is installed to monitor environmental parameters such as temperature, humidity and wind speed, and external factors influencing the performance of the arch rib are obtained. According to the method, data are subjected to MATLAB cleaning processing, a multi-layer neural network and an LSTM time sequence model are constructed through TensorFlow, arch rib durability scores and residual life prediction are generated, and high-risk area maintenance suggestions are provided for evaluation results. According to the method, multi-source data are comprehensively integrated, and accurate evaluation and long-term safety maintenance of the health state of the arch rib are realized.

The present invention relates to the field of image analysis technology, specifically to a method for semantic segmentation of cracks in concrete arch bridges based on multispectral imaging. The method comprises the following steps: collecting multi-time multispectral images using an unmanned aerial vehicle (UAV), segmenting crack regions using K-means on the multispectral images, extracting and sliding normalizing a multi-band spectral vector sequence to generate a principal axis spectral vector, calculating the spectral vector angle and rate of change to mark transition points, screening boundary points by combining directional consistency and gradient scoring, extracting spectral patterns through time-series alignment and Z-score standardization, evaluating discrete fluctuations and correcting anomalies to output a binary segmentation map of concrete arch bridge cracks. In the present invention, a reflectance spectrum sequence is constructed using multi-time multispectral images, crack identification accuracy is improved by combining principal axis features and a sliding window, texture interference is eliminated by using spectral vector angle changes and gradient scoring, and a standardized spectral pattern time series model is generated to enhance boundary location accuracy, reduce noise interference, and support long-term monitoring of structural damage.

The application relates to a device and method suitable for precise positioning of steel pull rods of arch feet of steel truss arch bridges, the device comprising a first positioning steel plate and a second positioning steel plate, the length of the steel pull rod in the concrete arch support foundation being L, L being divided into n sections, the first positioning steel plate being arranged at a starting point node, the second positioning steel plate being arranged at intermediate nodes, and a lower bearing plate being arranged at an end point node, a plurality of through holes being arranged on the first positioning steel plate and the second positioning steel plate, the through holes being used for the steel pull rod to pass through, the positions of the first positioning steel plate and the second positioning steel plate being fixed through four coordinates, steel frame structures being arranged between the first positioning steel plate and the second positioning steel plate, adjacent second positioning steel plates, the second positioning steel plates and the lower bearing plate, and the steel frame structures being welded with the first positioning steel plate and the second positioning steel plate. The application can position the steel pull rod, avoid the steel pull rod from being deflected under the dead weight or being deformed under the impact of concrete pouring, and ensure that the long steel pull rod is perpendicular to the upper and lower bearing plates during construction.

The invention relates to a method and device for determining the arch axis of an arch bridge, electronic equipment and a storage medium, and belongs to the technical field of bridge engineering.The method for determining the arch axis of the arch bridge comprises the steps that the main beam axis of a bridge floor in the arch bridge is determined, and the bridge floor of the arch bridge is located on an asymmetric longitudinal section line; determining two arch feet of the arch bridge on a main beam axis based on a preset calculation span in the arch bridge, and constructing a three-dimensional rectangular coordinate system by taking an intersection point of a horizontal line passing through the first arch foot and a central stake mark line of the arch bridge as an origin of coordinates; in the three-dimensional rectangular coordinate system, the centroid of the arch rib is determined based on the origin of the coordinates and the preset rise, curve fitting is conducted on the two arch feet and the centroid of the arch rib, and a projection curve of the arch axis of the arch bridge on the vertical face of the arch bridge and the coordinates of the position relation between the three-dimensional rectangular coordinate system and the arch rib in the three-dimensional rectangular coordinate system are obtained. According to the method, the arch axis of the through type simply supported basket arch bridge with the bridge deck located on the asymmetric longitudinal section line can be determined.

The invention discloses a method for setting and controlling a buckle cable adjustment threshold value in large-span arch bridge hoisting construction, which comprises the following steps of: acquiring construction parameters of a current buckle section, and acquiring a corresponding cable adjustment target value; constructing a structural mechanics finite element model of the target buckle cable based on the construction parameters, and introducing a buckle cable multi-harness nonlinear stress mechanism into the model to calculate upper and lower limit thresholds of cable force in the tensioning process; determining an elevation adjustment threshold according to the target axis, the target elevation, the accumulated deviation and the pre-deformation compensation amount in combination with a geometric linear control model; and generating an environmental influence correction coefficient by utilizing construction environmental parameters, and dynamically correcting the cable force and the elevation threshold value to realize real-time updating of the threshold value in the hoisting process. According to the method, the problems of nonlinearity of multiple wire harnesses of the large-span arch bridge buckle cable, high linear sensitivity of the arch rib, remarkable environmental influence and the like are solved, high-precision cooperation of cable force control and linear control is realized, and the safety, controllability and construction efficiency of hoisting construction are improved.