425 results about "Continuous beam" patented technology

The invention relates to the technical field of bridge bearing capacity evaluation, and discloses an existing continuous beam bridge bearing capacity comprehensive evaluation method which comprises the steps that multi-source data are collected to construct a three-dimensional damage voxel field, and an initial finite element model is generated; simulating a heavy load identification control section, and designing an equivalent static load test scheme according to an equivalent internal force principle; executing a field static load test, collecting elastic response data and constructing an actual measurement response vector; calculating errors and iteratively adjusting parameters in a voxel field constraint range to finish model correction; and generating an operation space-time security envelope based on the correction model, and comparing the state in real time to output a control instruction. A three-dimensional damage voxel field is constructed, voxels are used as a normalized data carrier, discrete apparent and internal damage data such as three-dimensional laser scanning point cloud, ultrasonic velocity and rebound strength are mapped into a continuously distributed space field, and the space variability of the rigidity of an existing bridge material can be represented in a refined mode. And the accuracy of describing the physical current situation of the structure by the initial finite element model is improved.

Additively manufactured articles of footwear comprising a sole portion and an upper portion 3D printed as a single piece. In some embodiments, the article of footwear can comprise an outer skin comprising a plurality of continuous beams extending adjacent to each other and defining at least part of an outer contour of the upper portion, at least part of an outer contour of the sole portion, or both. In some embodiments, the article of footwear can comprise an inner skin comprising a network of beams defining at least part of an inner contour of the upper portion. In some embodiments, the article of footwear can comprise a core structure that connects beams of the outer skin to beams of the inner skin.

The invention discloses a large transport vehicle bridge safety assessment method based on fuzzy comprehensive evaluation, which comprises the following steps: constructing a bridge bearing capacity reduction coefficient model, integrating four factors of material performance degradation, structural damage, environmental corrosion and load combination, and determining index weights by adopting an analytic hierarchy process; and a multi-stage evaluation system is established in combination with a fuzzy mathematics theory. A prestressed concrete continuous beam bridge in Jiangsu section of Jinghai highway is taken as an object, finite element simulation is used for analyzing the load effect of large vehicles under independent and mixed passing conditions, and verification shows that when the large vehicles pass at the mixing rate of 20%, the most unfavorable section safety coefficient of the bridge reaches 1.35, and the standard requirements are met. According to the method, fuzzy mathematics and structural mechanics analysis are creatively fused, a standardized process of parameter collection, model calculation and safety judgment is established, the efficiency is improved by 40% or above compared with a traditional static load test, the method is applied to transportation examination and approval of five bridges in Jiangsu province, a scientific basis is provided for selection of large transportation channels, and the risk of bridge damage is effectively prevented.

Additively manufactured articles of footwear comprising a sole portion and an upper portion 3D printed as a single piece. In some embodiments, the article of footwear can comprise an outer skin comprising a plurality of continuous beams extending adjacent to each other and defining at least part of an outer contour of the upper portion, at least part of an outer contour of the sole portion, or both. In some embodiments, the article of footwear can comprise an inner skin comprising a network of beams defining at least part of an inner contour of the upper portion. In some embodiments, the article of footwear can comprise a core structure that connects beams of the outer skin to beams of the inner skin.

The invention discloses a bridge fabrication machine construction full-period informatization management system based on an AI technology, and the system comprises a bridge fabrication machine global sensing subsystem which is used for collecting construction parameters in the construction operation process of a bridge fabrication machine; the edge processing subsystem is used for performing edge processing on the construction parameters acquired by the bridge fabrication machine global sensing subsystem; the digital twinning subsystem is used for establishing a digital twinning model for simulating the whole construction period of the bridge fabrication machine and synchronously mapping the construction parameters subjected to edge processing to the digital twinning model; and the safety monitoring subsystem is used for monitoring the working safety of the bridge fabrication machine based on the digital twin model. The method is used for solving the problems that in the prior art, the monitoring and analysis capacity of the construction process of the cantilever bridge fabrication machine is poor, and operation safety is not facilitated, and the purposes of informatization management of the construction process of the bridge fabrication machine and improvement of the safety and scientificity of the construction process of a continuous beam are achieved.

The invention provides a hanging basket steel plate sling limiting device, and relates to the technical field of continuous beam cantilever casting auxiliary tools, the hanging basket steel plate sling limiting device comprises a steel plate sling, a clamping plate, a working pin and a limiting assembly; the limiting assembly comprises a placing plate, a supporting plate and fixing plates, the supporting plate is arranged at the lower end of the placing plate, fixing assemblies for connecting the supporting plate and the clamping plates are arranged in the supporting plate, the two fixing plates are symmetrically arranged, connecting pipes are connected to the outer sides of the fixing plates, and the ends, away from the fixing plates, of the connecting pipes are connected with moving plates which are connected with fixing rods; an inner rod is elastically arranged in the fixing rod, one end of the inner rod extends out of the fixing rod and is fixedly provided with a limiting plate, through holes for the limiting plate to penetrate through are correspondingly formed in the clamping plate and the fixing plate, and a control assembly for controlling the connecting pipe to move in the direction perpendicular to the fixing plate is arranged on the fixing plate. The invention solves the problems that the sling is not positioned in the middle of a working pin, so that the distribution of load on the sling is influenced, the deflection of a hanging system is further caused, and local overload or uneven stress is caused.

The invention relates to the technical field of beam bridge splicing, in particular to a large-span concrete continuous beam bridge splicing construction method based on intelligent construction. The method comprises the following steps: acquiring digital modeling data of a left bridge and a right bridge to be spliced; analyzing the digital modeling data, and determining the dynamic stress distribution of the whole construction process; acquiring deformation monitoring data in real time, analyzing the deformation monitoring data, and determining a coordinated deformation rule of the left and right bridges; and generating a splicing construction scheme according to the dynamic stress distribution and the coordinated deformation rule. And the decoupling problem of a digital model and a physical entity is eliminated. The problem of stress control blind areas is solved, stress space-time evolution is quantified, it is ensured that stress prediction covers all stages of construction, and the blind areas of a conventional static model are avoided. The problem of quantitative deficiency of the coordination deformation rule is solved, and the defect of neglecting the deformation coordination is avoided. The problem of construction decision lag is solved, the structural damage probability and temperature cracks are reduced, and coupling of construction execution and a physical mechanism is ensured.

The invention discloses a simple layout method for distributed optical fiber deflection monitoring of a continuous beam bridge cluster, and the method comprises the steps: laying upper and lower edge strain sensing optical cables on a boundary beam of the continuous beam bridge cluster, only laying the lower edge strain sensing optical cable on a middle beam, and obtaining the deflection of the boundary beam through the upper and lower edge strain monitoring data of the boundary beam; and reconstructing the upper edge strain data of the middle beam by utilizing the upper edge strain data of the boundary beam, and realizing the accurate reconstruction of the deflection of the middle beam by combining the lower edge strain monitoring data of the middle beam through a continuous beam bridge deflection reconstruction method based on data-physical hybrid driving. The method not only solves the problems of large sensor consumption, complex arrangement, high construction cost, poor cluster monitoring economy and the like caused by simultaneous arrangement of optical fibers on the upper edge and the lower edge of each beam in the prior art, but also solves the problems of difficulty in arrangement of sensors and large construction damage caused by bridge deck pavement coverage on the upper edge of the middle beam; and the robustness and the data reconstruction capability of the monitoring system are effectively improved.

The invention discloses a bridge longitudinal and transverse displacement reconstruction method and system based on time sequence feature extraction, and relates to the technical field of bridge health monitoring. The method comprises the following steps: acquiring structural state data and environmental data of a continuous beam bridge and a cable-stayed bridge; analyzing a linear relation between the structure state data and the environment data by using a correlation coefficient analysis method; processing the related characteristics by using the bridge displacement reconstruction model to obtain three-dimensional displacement data of bridge reconstruction; and based on the obtained three-dimensional displacement data of the bridge reconstruction, screening key factors in related characteristics through a grid search algorithm, and optimizing the input of a bridge displacement reconstruction model. According to the method, the time sequence characteristics of the data are fully monitored to construct the De-SpcNet-based bridge displacement reconstruction model, so that the reconstruction precision of longitudinal and transverse displacement is improved. And then, model output is optimized through refined model parameter setting and a post-processing technology, so that the accuracy and stability of a reconstruction result are further improved.

The invention relates to the technical field of bridge construction, and provides a construction method for building continuous beams in parallel and a construction hanging basket. The construction hanging basket comprises a hanging basket body, a first hanging rod used for bearing the construction load of the hanging basket body is poured on the hanging basket body through concrete, and extension sections are bolted to the two ends of the hanging basket body; the extension section is provided with a second hanging rod used for guiding the hanging basket to move and temporarily supporting the extension section, through interval construction of the parallel-built continuous beams and by combining the avoiding design of the extension section, the problem of interference of small-interval parallel-built continuous beam hanging basket construction is solved, and the construction efficiency is effectively improved.

The invention relates to a stress monitoring data correction system for a continuous beam bridge under the temperature influence, in particular to the field of bridge health monitoring, and effectively solves the problem of bridge stress monitoring data distortion under the temperature influence through multi-module collaborative innovation. The trend modeling module dynamically predicts a drift evolution law and quantifies a confidence level, the compensation correction module fuses physical constraints to generate an anti-interference drift compensation amount, and the health prediction module realizes accurate life evaluation based on a time-varying mechanism, so that finally, the reliability of monitoring data is remarkably improved, and misjudgment of a structural damage state is avoided; maintenance decisions are optimized, full-life-cycle safety of the bridge is guaranteed, and meanwhile invalid operation and maintenance cost caused by false alarms is reduced.

The invention discloses a BIM (Building Information Modeling) and real-time monitoring-based cylindrical pier cast-in-place cantilever variable cross-section continuous beam bridge construction early warning system and method, and relates to the technical field of construction early warning. According to the system, alignment and noise reduction are carried out on monitoring data through BIM constrained drift correction, a curvature sequence and an acceleration sequence are obtained, an energy response index and an energy characteristic index are extracted, and a space-time distribution matrix is formed. And identifying a curvature deviation development trend by using a time sequence prediction model, and dynamically evaluating structural stress distribution and a deformation state in combination with finite element analysis. When the deviation value or the stress result exceeds a multi-level threshold value, finite element reanalysis is triggered for correction. And the decision execution module judges the real-time safety level and generates an early warning signal by integrating the monitoring characteristics and the simulation result based on a robust intelligent identification model subjected to ring loss regularization training. The method can improve the monitoring precision and robustness of the construction stage, and achieves the real-time, foresight and closed-loop management and control of the structure safety.

The invention relates to a shear key arrangement device and method for improving the crack resistance of a bridge deck in a hogging moment area of a steel-concrete combined continuous beam bridge, and belongs to the technical field of bridge engineering. Comprising a steel beam, a concrete bridge deck slab and stud shear keys arranged between the steel beam and the concrete bridge deck slab, and the rigidity of the shear keys can be adjusted according to needs so as to improve the stress performance of a concrete slab in a hogging moment area. According to the shear connectivity requirement, the total shear bearing capacity of the studs is calculated, the number of the studs is calculated according to the diameter of the selected stud type, the tensile stress of the concrete in the hogging moment area is calculated and compared with the designed allowable stress, and rigidity adjustment of the shear keys is achieved by changing the diameter and the number of the studs. And meanwhile, the total strength of the stud is kept unchanged. According to the scheme, the stress performance of the concrete slab in the hogging moment area of the steel-concrete combined continuous beam bridge can be effectively improved, meanwhile, the construction process is simplified, the safety is improved, the cost is reduced, the material performance is fully utilized, and the user experience is improved.

The invention discloses a method for rapidly evaluating the flexural rigidity of a bridge under vehicle-induced excitation, and belongs to the technical field of flexural rigidity evaluation of variable cross-section beams. The method comprises the following steps of: firstly, acquiring a bridge time-history response by adopting vehicle movement loading, separating a power component by utilizing a VMD method, then identifying a main frequency of an IMF component through FFT, removing the power component higher than a bridge fundamental frequency, and reconstructing a bridge actual measurement quasi-static time-history response; then, an axle effect in bridge actual measurement quasi-static time history response is eliminated, an influence line recognition model is established, and Tikhonov regularization is introduced to further solve a deflection influence line; then deriving an analytic solution of a deflection influence line of the variable cross-section continuous beam based on a virtual work principle, establishing a mathematical relationship between the flexural rigidity and the deflection influence line, and identifying the flexural rigidity of the bridge through the deflection influence line based on the mathematical relationship to obtain flexural rigidity distribution of the full bridge; finally, multiple evaluation indexes are defined and calculated, the bending rigidity distribution of the full bridge is comprehensively evaluated, and the method has the advantages of being good in engineering applicability and high in safety evaluation innovativeness.

The invention relates to the technical field of bridge jacking construction, in particular to a large-area special-shaped continuous beam asynchronous jacking system and a jacking construction method. According to the method, jacking force is pre-distributed based on a finite element model and a historical data training machine learning algorithm, and high-precision deformation coordination control is achieved through a hydraulic jack group and a multi-sensor cooperative monitoring network (including displacement, strain, inclination angle and deflection parameters) placed on a special-shaped beam in combination with an iteratively optimized graded jacking and dynamic compensation strategy. Comprising the steps that the total jacking height is constructed in a graded mode, and in each stage of jacking, output of all fulcrums is adjusted in real time through a PLC so that the displacement synchronization error can be kept to be smaller than or equal to 0.5 mm; when it is monitored that local stress exceeds the limit, a dynamic compensation mechanism is triggered, and secondary balance of the load is achieved by jacking and accelerating an overstress point and jacking adjacent fulcrums in a reinforcement mode. According to the method, the problems of stress concentration, local support disengaging and the like caused by uneven stress in the jacking process of the special-shaped continuous beam are solved.

The invention relates to the technical field of construction supports, and discloses a bridge high pier continuous beam construction support. A continuous beam; the supporting mechanism is arranged on the bridge pier, the supporting mechanism is used for providing stable supporting, and the supporting mechanism comprises a base supporting plate; and the positioning mechanism is arranged on the base supporting plate. According to the bridge high pier continuous beam construction support, the righting mechanism is arranged, hydraulic oil is driven by the telescopic motor to push the top supporting plate and the four top pressing columns to synchronously act on the bottom and the side wall of a continuous beam, symmetrical and controllable multi-point positioning extrusion is formed, and the problem that the position of the continuous beam cannot be adjusted after hoisting through a traditional support is solved; even if the continuous beam is not completely aligned during first hoisting, accurate fine adjustment can be achieved through the support structure, the splicing precision is greatly improved, repeated hoisting is avoided, the construction efficiency is improved, and the safety risk is reduced.

The invention discloses a non-full-length beam steel bar material breaking optimization method based on a hybrid optimization algorithm, and aims to solve the problem that an existing non-full-length beam steel bar material breaking method cannot balance the steel bar utilization rate and the calculation efficiency. The method comprises the following steps: for required beam steel bars under the same beam steel bar diameter, dividing the required beam steel bars into two groups according to the length of the beam steel bars; for required beam steel bars with the length larger than 12 m, a cut excess material splicing method is adopted, an optimized mathematical model of steel bar excess materials is established, and the number of used raw material steel bars and the division length of the raw material steel bars are calculated and determined through a genetic algorithm; and for required beam steel bars with the length smaller than 12 m, directly cutting from a single raw material steel bar or combining and processing the raw material steel bars with different specifications, listing all cutting modes, calculating steel bar excess materials corresponding to the cutting modes, and minimizing the total steel bar excess materials by the integer linear programming model to obtain a steel bar broken material combination scheme.

The invention discloses a corrugated steel web box girder hogging moment area shear nail push-out test device and method.The corrugated steel web box girder hogging moment area shear nail push-out test device comprises a corrugated steel web combined box girder, a loading frame, a pulley support, a jack and a displacement measuring device, and a reinforced concrete plate of the corrugated steel web combined box girder is connected with a corrugated steel web through shear nails; the cross beam of the loading frame applies symmetrical vertical pressure to the reinforced concrete slab through the jack, the stand column applies horizontal push-out force to the lower sliding support through the jack, the reinforced concrete slab is pushed out of the top face of the steel box girder, and a shearing force sliding curve is recorded through the displacement measuring device and the pressure sensor. Through a two-way loading mode of first vertical and then horizontal, the shear bearing capacity of the shear nail under the actual cracking condition of a hogging moment region concrete slab is more effectively simulated, a test device for only applying one-way force to the shear nail is improved, the real stress condition of the continuous beam bridge hogging moment region is met, and the displacement measurement device is simple in structure, stable in clamping and high in practicability. The relative slippage of the shear nails is effectively measured.

The invention discloses a geometric irregularity state deterioration characterization method for a longitudinally-connected ballastless track on a high-speed railway bridge under a transverse earthquake, and the method comprises the steps: building a refined finite element model of a longitudinally-connected ballastless track-bridge system, and analyzing the damage characteristics and distribution rules of key components of the earthquake-caused track-bridge system; the characteristic of damage state degradation of key components of the earthquake-induced track-bridge system and a mapping mechanism are disclosed; then, based on the second theorem of Castlliano and the superposition principle, a geometric irregularity state deterioration characterization model of the longitudinally-connected ballastless track on the high-speed railway bridge under the action of the transverse earthquake is constructed, the geometric irregularity state of the longitudinally-connected ballastless track on the simply-supported / continuous beam bridge is mapped based on the deterioration characterization model, deformation data of the steel rail under the action of the earthquake are accurately quantified, and the accuracy of the deformation of the steel rail under the action of the transverse earthquake is improved. The method provides a theoretical basis for quickly judging the post-earthquake traffic capacity and maintenance engineering of a track-bridge system, ensures the operation safety of a high-speed railway, provides a theoretical basis for the design of a high-speed railway track-bridge, is beneficial to post-earthquake track repair and train operation recovery, and has a good practical value and a good popularization prospect.

The invention relates to the technical field of bridge health monitoring, and discloses a stay cable damage identification method of influence line cubic spline interpolation micro separation difference, comprising the following steps: S1, constructing an elastic support continuous beam model considering shear deformation and rotational inertia, and establishing a mapping relationship between support stiffness matrix difference before and after damage and cable force influence line change, calculating the cable force influence lines before and after damage, and making a difference to obtain a cable force influence line difference curve; s2, cubic spline interpolation differential is carried out on the cable force influence line difference curve; and S3, sequentially carrying out smoothing processing and mean variance separation calculation on the curvature curve. By constructing an elastic support continuous beam model integrated with shear deformation and rotational inertia and cooperating with a force normal equation of full-bridge support interaction, a cable force influence line difference curve can be accurately calculated, compared with a traditional model, the curve is more accurate, a solid data foundation is laid for damage identification, the identification accuracy is remarkably improved, and it is ensured that damage diagnosis is more reliable.

The invention belongs to the technical field of process control, and discloses a high-speed rail large-span continuous beam linear whole-process control method. Comprising the following steps: collecting continuous beam structure parameter data in real time and cleaning the data to obtain continuous beam construction data; elevation fluctuation interference identification is carried out, and an elevation difference mutation area is output; performing leveling control based on the height difference abrupt change area to obtain leveling correction data; performing stress interference correction to obtain disturbance correction linear data; tensioning plan information is obtained in real time, tensioning offset correction is conducted on the tensioning plan information, and tensioning correction parameter data are generated; construction climate data are collected, tensioning control calibration is carried out on the tensioning correction parameter data, and calibration control stress data are output; zero offset compensation is executed, and monitoring data in the offset restoration process are output; constructing a control strategy based on the monitoring data of the offset repairing process, and sending the control strategy to a preset construction control terminal; and the stability and the data accuracy of linear control are improved.

The present invention discloses a method for calculating the negative bending moment impact coefficient of small and medium span prefabricated continuous beam bridges based on a quasi-design state, including the following processes: determining the second-order vertical bending frequency of the bridge; determining the bridge deck roughness grade; and calculating the negative bending moment impact coefficient under the unevenness grade of the bridge deck using the second-order vertical bending frequency of the bridge. Based on the quasi-design state of the bridge, the present invention calculates the impact coefficient using the measured second-order frequency and roughness data of the bridge; at the same time, it can also adjust the impact coefficient assessment standard in a timely manner according to the degree of deterioration of the road surface grade. Therefore, the present invention can realize the evaluation of the negative bending moment impact coefficient of the continuous beam bridge according to the bridge deck condition in different operation periods, and has stronger pertinence and wider applicability.

The invention discloses a corrugated steel web continuous beam bridge construction linear control method and computing equipment. The method comprises the following steps that bridge linear twin data are obtained; based on the obtained bridge linear twinborn data, establishing a corrugated steel web continuous beam bridge digital twinborn model; the digital twin model of the corrugated steel web continuous beam bridge is assembled; updating and verifying the assembled digital twin model of the corrugated steel web continuous beam bridge; and correcting the digital twinborn model of the corrugated steel web continuous beam bridge based on a cyclic nesting mode, and performing monitoring and early warning on a physical entity. According to the method, a digital twinborn model of the corrugated steel web continuous girder bridge is established by obtaining linear twinborn data of the bridge; by correcting the digital twinborn model of the corrugated steel web continuous beam bridge and performing monitoring and early warning on a physical entity, accurate monitoring on linear and section information in the construction stage of the corrugated steel web continuous beam bridge is realized, so that the construction efficiency and quality are improved.

The invention discloses a bridge model correction method of a frequency and deflection influence line dual-objective function, and belongs to the technical field of bridge finite element model correction. According to the method, the VMD is combined with the Tikhonov regularization influence line identification method, vehicle-induced bridge response power components and multi-axis effect interference are effectively eliminated, the actually-measured deflection time history response of the bridge is restored to the deflection influence line under the unit concentrated load, the effect of identifying the variable-cross-section steel-concrete combined continuous beam bridge influence line is good, and the applicability is wide; according to the model correction method based on combination of a PSO-BP agent model and NSGA-II dual-objective optimization, a complex implicit function relationship between a to-be-corrected parameter and an objective function can be effectively constructed, a Pareto coordinated optimal solution under the dual-objective optimization problem is obtained, then a corrected parameter is obtained, and finite element model correction is achieved.

The invention discloses a BIM-based large-space pipeline installation method and system, and relates to pipeline installation: performing three-dimensional gridding processing on BIM model data, generating a gridding space model, and constructing a pipeline installation space; calculating the load per unit length of the pipeline according to the self weight of the pipeline and the weight of a medium in the pipeline in the physical parameters; a dynamic planning method is adopted for optimization arrangement of the supports and hangers; constructing a state transition equation according to the load per unit length of the pipeline and the structural mechanics continuous beam model; according to the state transition equation, an optimal decision sequence is obtained through reverse recursion solution, backtracking is conducted from the tail end of the pipeline to the starting point, in each decision stage, the position of a supporting point enabling accumulated deflection of all follow-up pipe sections to be minimum is selected, and a globally optimal supporting and hanging bracket arrangement sequence is generated; according to the globally optimal arrangement sequence of the supports and the hangers and the load per unit length of the pipeline, the deflection value of each pipe section is calculated; according to the method, the problem of non-uniform deflection distribution caused by a traditional local optimization method is avoided.

The invention discloses a continuous beam bridge closure construction monitoring system and method, and relates to the technical field of construction monitoring. Comprising an acquisition module for acquiring endpoint position information of a target erected bridge, acquiring a target endpoint item, acquiring an erection path based on the target endpoint item, acquiring erection data of the target bridge by taking the target endpoint item as an initial feature point, and acquiring divided erection items; and the marking module is used for acquiring starting point position data and ending point position data of the divided erection item to obtain marked feature points, and acquiring a point connecting line based on the marked feature points to obtain a marked path. According to the method, the difference between the first monitoring set and the second monitoring set is compared, the positions with differences are judged as the difference feature areas, the positions with differences between the first monitoring set and the second monitoring set are judged as the judgment difference areas, and dynamic addition of the monitoring nodes is performed on the judgment difference areas, so that the key monitoring effect on the difference positions is realized.

The application discloses a method for installing a steel reinforcement cage in continuous beam construction, wherein: the steel reinforcement cage is installed by using a cantilever pouring and walking integrated machine; the cantilever pouring and walking integrated machine comprises a support framework system and a walking system, and the walking system is arranged at the lower part of the support framework system; the cantilever pouring and walking integrated machine walks to the front end of a completed continuous beam section through the walking system, hoists and transports the prefabricated steel reinforcement cage from the rear end of the support framework system to the front end, adjusts the angle, front and back and left and right positions of the steel reinforcement cage to be consistent with the angle, front and back and left and right positions of the next continuous beam pouring section, and then lowers the steel reinforcement cage to the design position between the assembled outer forms. The application can hoist and transport the prefabricated steel reinforcement cage to the top of the design position of the next continuous beam pouring section by using the cantilever pouring and walking integrated machine, and then lower the steel reinforcement cage, so that the problems of long construction period and difficult guarantee of engineering quality caused by scattered steel reinforcement cage assembly operation can be overcome.

The invention relates to the technical field of building design, and particularly discloses a large-span steel structure cantilever platform which comprises a cantilever structure and a foundation supporting structure arranged at the bottom of the cantilever structure. The cantilever structure comprises a cantilever main span and side spans, the two ends of each side span are arranged at the two ends of the cantilever main span, the side spans are connected with the cantilever main span, and the two side spans and the cantilever main span are connected to form a three-span curve continuous beam structure. Through the continuity of the two groups of side spans and the cantilever main span, a cantilever beam consolidation system formed by a cantilever platform in the prior art is converted into a three-span curve continuous beam system, so that the temperature force can be effectively released, and the stress is more reasonable; the generated bending moment is balanced by the dead weight of the side span and the counter weight; and the span of the cantilever platform is not limited any more, and large-span cantilever platforms are facilitated.

The invention relates to a method for controlling overturning stability of a variable-width continuous beam bridge in an asymmetric construction process, which comprises the following steps of: mounting a temporary supporting rod piece on a bearing platform of a main pier of the bridge, and fixedly connecting the lower end of the temporary supporting rod piece with the bearing platform; after the formwork of the main beam section is removed, strain sensors are installed on the surfaces of the fixed supporting rod piece and the adjustable supporting rod piece, and a tilt angle sensor is installed on the fulcrum section of the main beam section; strain and inclination angle data are collected in real time through a monitoring system, and supporting axial force, deformation and unbalanced torque are calculated; and dismantling the temporary support member, the hydraulic equipment and the monitoring sensor after the side span is closed. The method has the beneficial effects that the stress of the temporary supporting structure and the inclination state of the main beam can be monitored in real time, the change condition of the overturning moment is calculated in real time through a corresponding algorithm, and meanwhile the early warning function is achieved.

The invention provides a laser communication device for rapid link establishment and networking and a satellite internet constellation. The device utilizes the wavelength division multiplexing unit and the pre-aiming unit to realize beam combination of receiving and transmitting optical path signals so as to improve the coaxiality of receiving and transmitting branches; an optical fiber displacement device arranged on the transmitting-receiving lens is used for adjusting the relative position of the beam combining optical fiber and the focal point of the transmitting-receiving lens, and continuous beam changing of a transmitted light path signal within the divergence angle range of 55-1000 microrad is achieved; and a position sensing unit is matched to focus a receiving light path signal, so that a 0.2-1-degree receiving light path continuous field of view is realized. Through 10000 times of offset error estimation simulation, the coverage rate of an uncertain area to a target light spot reaches 99.32%, and about 1mrad beam change can be realized, so that minute-level capture efficiency is realized under the condition of the continuous field of view.