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Fatigue Crack Propagation Law of Corroded Steel Box Girders in Long Span Bridges
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作者 Ying Wang Longxiao Chao +1 位作者 Jun Chen Songbai Jiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期201-227,共27页
In order to investigate the fatigue performance of orthotropic anisotropic steel bridge decks,this study realizes the simulation of the welding process through elastic-plastic finite element theory,thermal-structural ... In order to investigate the fatigue performance of orthotropic anisotropic steel bridge decks,this study realizes the simulation of the welding process through elastic-plastic finite element theory,thermal-structural sequential coupling,and the birth-death element method.The simulated welding residual stresses are introduced into the multiscale finite element model of the bridge as the initial stress.Furthermore,the study explores the impact of residual stress on crack propagation in the fatigue-vulnerable components of the corroded steel box girder.The results indicate that fatigue cracks at the weld toe of the top deck,the weld root of the top deck,and the opening of the transverse diaphragm will not propagate under the action of a standard vehicle load.However,the inclusion of residual stress leads to the propagation of these cracks.When considering residual stress,the fatigue crack propagation paths at the weld toe of the transverse diaphragm and the U-rib weld toe align with those observed in actual bridges.In the absence of residual stress,the cracks at the toe of the transverse diaphragm with a 15%mass loss rate are categorized as type I cracks.Conversely,when residual stress is considered,these cracks become I-II composite cracks.Residual stress significantly alters the cumulative energy release rate of the three fracturemodes.Therefore,incorporating the influence of residual stress is essential when assessing the fatigue performance of corroded steel box girders in long-span bridges. 展开更多
关键词 Residual stress crack propagation corroded steel box girder cumulative energy release rate
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Experimental study on box shape steel reinforced concrete beam 被引量:3
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作者 杨春 蔡健 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期463-468,共6页
Experimental study on the fundamental behavior of box shape steel reinforced concrete (SRC) beams was conducted. Seven 1 : 3 scale model SRC beams were tested to failure. The experimental results indicate that the ... Experimental study on the fundamental behavior of box shape steel reinforced concrete (SRC) beams was conducted. Seven 1 : 3 scale model SRC beams were tested to failure. The experimental results indicate that the flexural strength increases with the increase of the ratio of flexural reinforcement and the thickness of flange of the shape steel; the shear strength increases with the increase in the thickness of the web of the shape steel. Concrete filled in the box shape steel can prevent the early failure of specimens due to the buckling of the box shape steel, and increase the ultimate load. Measures should be made to strengthen the connection and co-work between the shape steel and the concrete. Formulae for flexural and shear strength of the composite beams are proposed, and the calculated results are in good agreement with the experimental results. In general, the box shape SRC beam is a kind of ductile member, and it is suitable for extensive engineering application. 展开更多
关键词 steel reinforced concrete (SRC) experimental study ultimate strength box shape steel
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Lateral-torsional buckling of box beam with corrugated steel webs 被引量:9
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作者 FENG Yu-lin JIANG Li-zhong +1 位作者 ZHOU Wang-bao HAN Jian-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第7期1946-1957,共12页
Corrugated steel web is folded along the longitudinal direction and has the mechanical properties such as axial compression stiffness corrugation effect, shear modulus corrugation effect, similar to that of an accordi... Corrugated steel web is folded along the longitudinal direction and has the mechanical properties such as axial compression stiffness corrugation effect, shear modulus corrugation effect, similar to that of an accordion. In order to study the lateral-torsional buckling of box beams with corrugated steel webs (BBCSW) under the action of bending moment load, the neutral equilibrium equation of BBCSW under the action of bending moment load is derived through the stationary value theory of total potential energy and further, along with taking Kollbrunner-Hajdin correction method and the mechanical properties of the corrugated web into consideration. The analytical calculation formula of lateral-torsional buckling critical bending moment of BBCSW is then obtained. The lateral-torsional buckling critical bending moment of 96 BBCSW test specimens with different geometry dimensions are then calculated using both the analytical calculation method and ANSYS finite element method. The results show that the analytical calculation results agree well with the numerical calculation results using ANSYS, thus proving the accuracy of the analytical calculation method and model simplification hypothesis proposed in this paper. Also, compared with the box beams with flat steel webs (BBFSW) with the same geometry dimensions as BBCSW, within the common range of web space-depth ratio and web span-depth ratio, BBCSW’s lateral-torsional buckling critical bending moment is larger than that of BBFSW. Moreover, the advantages of BBCSW’s stability are even more significant with the increase of web space-depth ratio and web depth-thickness ratio. 展开更多
关键词 box beams with corrugated steel webs lateral-torsional buckling analytical solution accordion effect Kollbrunner-Hajdin method
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Erosion problem in tool steel using cold box core-making process 被引量:2
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作者 Eduardo Rodríguez Alberto Pérez +5 位作者 Rafael David Mercado-Solis Velasco-Téllez Abraham Omar Jimenez Martin Flores Marco Aurelio Gonzalez Jesus Ibarra 《China Foundry》 SCIE 2019年第3期204-210,共7页
This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens... This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles. 展开更多
关键词 EROSION cold box core-making H13 tool steel RESIN coated silica SAND
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Estimating extreme temperature differences in steel box girder using long-term measurement data 被引量:5
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作者 丁幼亮 王高新 《Journal of Central South University》 SCIE EI CAS 2013年第9期2537-2545,共9页
The extreme temperature differences in fiat steel box girder of a cable-stayed bridge were studied.Firstly,by using the long-term measurement data collected by the structural health monitoring system installed on the ... The extreme temperature differences in fiat steel box girder of a cable-stayed bridge were studied.Firstly,by using the long-term measurement data collected by the structural health monitoring system installed on the Runyang Cable-stayed Bridge,the daily variations as well as seasonal ones of measured temperature differences in the box girder cross-section area were summarized.The probability distribution models of temperature differences were further established and the extreme temperature differences were estimated with a return period of 100 years.Finally,the temperature difference models in cross-section area were proposed for bridge thermal design.The results show that horizontal temperature differences in top plate and vertical temperature differences between top plate and bottom plate are considerable.All the positive and negative temperature differences can be described by the weighted sum of two Weibull distributions.The maximum positive and negative horizontal temperature differences in top plate are 10.30 ℃ and -13.80 ℃,respectively.And the maximum positive and negative vertical temperature differences between top plate and bottom plate are 17.30 ℃ and-3.70 ℃,respectively.For bridge thermal design,there are two vertical temperature difference models between top plate and bottom plate,and six horizontal temperature difference models in top plate. 展开更多
关键词 structural health monitoring cable-stayed bridge steel box girder temperature difference extreme value analysis
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Fatigue Performance of Orthotropic Steel Decks in Super-Wide Steel Box Girder Considering Transverse Distribution of Vehicle Load 被引量:2
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作者 Xudong Wang Changqing Miao +1 位作者 Mao Yang Youliang Ding 《Structural Durability & Health Monitoring》 EI 2021年第4期299-316,共18页
This study presents an investigation on the fatigue analysis of four types of details on orthotropic steel decks(OSDs)for a cable-stayed super-wide steel box girder bridge based on finite-element analysis(FEA)with veh... This study presents an investigation on the fatigue analysis of four types of details on orthotropic steel decks(OSDs)for a cable-stayed super-wide steel box girder bridge based on finite-element analysis(FEA)with vehicle transverse distribution model(VTDM).A high-fidelity 3D FE model verified by the static load test is established to satisfy the fatigue analysis accuracy.The stress behavior of super-wide steel box girders under the vehicle load at different lane locations is investigated.Then,considering the effect of VTDM,the fatigue life analysis of four typical details is performed using the Miner cumulative damage rule.The results show that the vehicle transverse location has a great influence on the stress behavior of details with sharp influence surface,and the stress ranges in the outermost lane are larger than those in other lanes,indicating that the details of OSD in the outermost lane are prone to fatigue.The fatigue life analysis indicates that the diaphragm cutout is more prone to fatigue than other details,which should be carefully treated in bridge maintenance. 展开更多
关键词 Orthotropic steel deck steel box girder fatigue life vehicle transverse distribution model finite element analysis
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The study of temperature effects on steel box girder for Taizhou Bridge 被引量:2
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作者 Miao Changqing Feng Zhaoxiang +1 位作者 Wang Yichun Shi Changhua 《Engineering Sciences》 EI 2012年第3期81-87,共7页
Using the temperature gradient which was proposed by continuously measuring flat steel box girder of Runyang Bridge, temperature effects of flat steel box girder were studied for Taizhou Bridge. With three temperature... Using the temperature gradient which was proposed by continuously measuring flat steel box girder of Runyang Bridge, temperature effects of flat steel box girder were studied for Taizhou Bridge. With three temperature gradient models (JTG D60--2004 specification, BS5400 specification and the temperature gradient which was proposed in this paper), the stress of control sections was calculated by finite element program ANSYS. The calculated result indicated that the temperature gradient that was put forward in JTG D60-2004 specification and BS5400 specification for calculating the stress of fiat steel box girder was not suitable to apply to fiat steel box girder. The temperature gradient on flat steel box girder which was proposed in this paper was reasonable. 展开更多
关键词 suspension bridge flat steel box girder temperature gradient STRESS
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Fatigue Performance Analysis and Evaluation for Steel Box Girder Based on Structural Health Monitoring System 被引量:1
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作者 Meiling Zhuang Changqing Miao Rongfeng Chen 《Structural Durability & Health Monitoring》 EI 2020年第1期51-79,共29页
Taizhou Yangtze River Bridge as a long-span suspension bridge,the finite element model(FEM)of it is established using the ANSYS Software.The beam4 element is used to simulate the main beam to establish the“spine beam... Taizhou Yangtze River Bridge as a long-span suspension bridge,the finite element model(FEM)of it is established using the ANSYS Software.The beam4 element is used to simulate the main beam to establish the“spine beam”model of the Taizhou Yangtze River Bridge.The calculated low-order vibration mode frequency of the FEM is in good agreement with the completion test results.The model can simulate the overall dynamic response of the bridge.Based on the vehicle load survey,the Monte Carlo method is applied to simulate the traffic load flow.Then the overall dynamic response analysis of FEM is car-ried out.Taking the bending moment of the main beam as the control index,the fatigue sensitive section in the steel box girder of FEM is analyzed.Based on the strain time history data of steel box girder recorded by the structural health mon-itoring system(SHM),the true stress response of steel box girder under vehicle load is extracted.Taking the cumulative fatigue damage increment as the evalua-tion index,the fati gue performance evaluation of the steel box girders is con-ducted based on the collected health monitoring data.The fatigue effect of the beam section near the steel tower,especially the first section of the middle tower,is the key section of the fatigue analysis by health morning system,which is con-sistent with the calculation results of FEM. 展开更多
关键词 steel box girder FATIGUE stress response Monte Carlo method structural health monitoring system
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Study in the design and manufacture process of the elastic cable anchor box in steel box girder of Taizhou Bridge 被引量:1
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作者 Gu Bifeng Chen Ce Ding Lei 《Engineering Sciences》 EI 2011年第2期64-68,共5页
Taizhou Yangtze River Highway Bridge is a large span suspension bridge with three pylons. The elastic cables are installed to connect the steel tower and the steel box girder. The constraints can increase the safety c... Taizhou Yangtze River Highway Bridge is a large span suspension bridge with three pylons. The elastic cables are installed to connect the steel tower and the steel box girder. The constraints can increase the safety coefficient of the middle saddle, and improve the stress conditions of the middle pylon and decrease the deflection in the middle of the main girder, as well as the longitudinal displacement of the main girder caused by live loads. The anchorage boxes of the elastic cable are installed in the wind fairing outside the vertical web plate of the box girder. Two anchor boxes form a pair and are arranged parallelly. Eight anchor boxes are installed in the bridge. In this paper, the design scheme and the technical difficulties in manufacturing are briefly discussed with the precision control techniques. 展开更多
关键词 Taizhou Bridge steel box girder the elastic cables DESIGN manufacture techniques
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GMA material design and construction quality control for asphalt pavement of steel box girder: Case study of the Hong Kong–Zhuhai–Macao Bridge 被引量:2
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作者 Xiaoning Zhang 《Journal of Road Engineering》 2021年第1期63-72,共10页
To improve the quality of the Hong Kong–Zhuhai–Macao Bridge paving project,a new paving layer material,Guss-mastic asphalt(GMA),was proposed in this paper by combining the advantages of two types of cast asphalt mix... To improve the quality of the Hong Kong–Zhuhai–Macao Bridge paving project,a new paving layer material,Guss-mastic asphalt(GMA),was proposed in this paper by combining the advantages of two types of cast asphalt mixtures:mastic asphalt(MA)and Guss asphalt(GA).Based on the characteristics of GMA,to simulate its actual production process,this study developed a small-simulated cooker mixing equipment.Moreover,the flow degree,60C dynamic stability,and impact toughness were proposed to be used to evaluate the construction and ease,high temperature stability,and fatigue resistance of GMA cast asphalt mixtures,respectively.Moreover,the quality control standards for GMA paving materials by indoor tests,field trial mix GMA material performance tests,and accelerated loading tests were finalized.The study showed that the developed simulated cooker yielded consistent mixing results in the same working environment as the engineering cooker device.Increasing the coarse aggregate incorporation rate,coarsening the mastic epure(ME)gradation composition,and using a smaller oil to stone ratio can reduce the flowability of the GMA materials to varying degrees.The four-point bending fatigue life and impact toughness of the different GMA materials are correlated well.A mobility of<20 s,60C dynamic stability of 400–800 times/mm,15C impact toughness of400 N⋅mm,and cooker car mixing temperature control standard of 210C–230C form an appropriate control index system for the design and production of GMA cast asphalt mixtures.Simultaneously,accelerated loading tests verified the accuracy and reliability of the quality control index system that has been used in the GMA paving project of the Hong Kong–Zhuhai–Macao Bridge deck and has achieved good application results. 展开更多
关键词 Asphalt pavement Material design GMA steel box girder Construction quality control
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Research on overall assembling and welding process of steel box girder tuyere blocks of Taizhou Bridge
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作者 Yan Shiguang Li Hongtao Wang Chao 《Engineering Sciences》 EI 2012年第3期21-25,共5页
This article presents in detail the assembling and welding process technique of the steel box girder tuyere blocks of Taizhou Bridge. The application of this process technique effectively solves the problem of welding... This article presents in detail the assembling and welding process technique of the steel box girder tuyere blocks of Taizhou Bridge. The application of this process technique effectively solves the problem of welding stress release in tuyere block assembling and welding without increasing the number of turns of the blocks and overhead welding, thus avoiding possible structural deformation due to excessive accumulation of internal welding stress, greatly reducing the repeated deformation and correction work during assembling and welding, and ensuring the weld seam quality and overall dimensions of tuvere blocks of Taizhou Bridze. 展开更多
关键词 Taizhou Bridge steel box girder TUYERE PROCESS
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Stress and noises of steel box girders in Sutong Bridge
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作者 Xue Tao Chen Zhijian Dong Xuewu 《Engineering Sciences》 EI 2008年第4期53-59,共7页
Sutong Bridge is a cable-stayed bridge with a main span of 1 088 m. 370 high-precision stress monitoring measured data show that in the process of hoisting the steel box girders,the stress of the main girders is in th... Sutong Bridge is a cable-stayed bridge with a main span of 1 088 m. 370 high-precision stress monitoring measured data show that in the process of hoisting the steel box girders,the stress of the main girders is in the fluctuant and complex state and many meteorological factors,such as sunshine radiation,temperature and wind,have important influence on the change of stress of the steel box girders. According to the real-time weather data,the stress data after the process of wavelet denoising from representative measuring points in different weather conditions is picked to establish the stress response brought by meteorological factors with Layered Separation method,thereby basically eliminating the influence of meteorological factors on the stress of main girders,so that accurate and reliable stress data can be got for steel box girders adjustment and cable-tensioned construction control. 展开更多
关键词 Sutong Bridge cable-stayed bridge steel box girder wavelet denoising meteorological factor Layered Separation method
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Design of steel box girder for Taizhou Yangtze River Highway Bridge
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作者 Ding Lei Shan Hongwei Zhou Qing Zheng Benhui 《Engineering Sciences》 EI 2011年第2期57-63,共7页
Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The main girder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technica... Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The main girder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technically mature besides beautiful appearance. Straight web plates of the steel box girder in longitudinal direction are proposed in order to ensure the integrity of the steel box girder, and to keep the stress of the steel box girder continuous in the middle pylon, as well as to reduce the gradient of the middle pylon columns. The cross section of the box girder has one box with three cells. Solid-web diaphragm plate with good integrity and high torsional stiffness is adopted. The lifting lugs are utilized in the anchors of suspender cable. In this paper, selection of the cross section of the steel box girder, the general structure design, local structure design and main structure calculation results of Taizhou Yangtze River Bridge are introduced emphatically. 展开更多
关键词 Taizhou Yangtze River Highway Bridge three-pylon suspension bridge steel box girder DESIGN
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Research on Construction Process of Steel Box Girder Bridge and Its Stress Analysis
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作者 ChengKANG 《International Journal of Technology Management》 2015年第3期104-106,共3页
The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a b... The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a big cantilever thin-walled steel box girder section, namely the shear coefficient computation theory of Professor Hu Haichang, and the use of this shear area perfect beam element model, structure model and the experiment prove that the shell model is more consistent, given a certain reference for similar section project. 展开更多
关键词 Construction control Long-span steel box continuous girder Large segment hosting
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Study on the Mechanical Properties of Irregular Curved Steel Box Girder for City Viaduct
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作者 XijunYin 《International Journal of Technology Management》 2014年第1期46-48,共3页
This paper deeply analyses the influence of different local tectonic on stress performance of spatial curved steel box Girder Bridge, using the finite element analysis software to establish space finite element model ... This paper deeply analyses the influence of different local tectonic on stress performance of spatial curved steel box Girder Bridge, using the finite element analysis software to establish space finite element model of this bridge, calculation and analysis were made on the bridge of the strength, stiffness. It has certain reference value for guiding engineering design, have a good foundation for the mechanical properties and stability of linear and nonlinear further study of curved steel box girder. 展开更多
关键词 elastic buckling analysis U rib bridge deck curved steel box girder
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Analysis of Key Technologies in the Design of Small and Medium Span Basket Type Steel Box Tied Arch Bridge
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作者 Zhongyu Wang 《Journal of World Architecture》 2021年第4期49-55,共7页
In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design p... In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design process.It is hoped that this analysis can provide corresponding reference for the design and construction of this kind of arch bridge. 展开更多
关键词 Medium and small span Basket type steel box tie arch bridge Arch Bridge Design Key technology
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Corrosion Management of Aging Steel Bridges
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作者 Narendra Tripathi 《Journal of Civil Engineering and Architecture》 2024年第11期545-551,共7页
A significant portion of the sum spent by asset managers in maintaining steel bridge assets is dedicated to corrosion management of aging steel bridges,particularly very old ones.Managing corrosion of such bridges pos... A significant portion of the sum spent by asset managers in maintaining steel bridge assets is dedicated to corrosion management of aging steel bridges,particularly very old ones.Managing corrosion of such bridges poses unique challenges owing to the inherent complexities associated with design,material,fabrication and construction.Steel bridges have come a long way from being constructed of cast iron and wrought iron in the early days to modern day low carbon high strength steel bridges.During inception of steel bridges in Australia,wrought iron was used extensively in deck structure whereas piers were generally constructed of cast iron.Some of these piers have been found to be suffering from graphitisation.Even though CP(cathodic protection)has been proven to enhance the life of steel and reinforced concrete structures by preventing any further corrosion,there is little evidence to validate its success in preventing graphitisation of cast iron piers.Early steel bridges in NSW(New South Wales)were constructed with a complex geometry involving riveted cellular box girders,later simplified to riveted trusses.For any rehabilitation work to begin,the challenges start at the investigation stage.Due to cellular box type construction,thorough inspection and examination of inside of the boxes is generally not feasible even with the use of the available state-of-the-art investigation techniques.Some of the steel bridges in service in NSW are more than 120 years old.Any rehabilitation effort for such bridges faces challenges in terms of design methods to be used,availability of compatible material,selection of an appropriate method of joining e.g.welding or bolting,selection of a compatible protective coating,accessibility for the work to be carried out,etc.This paper describes common forms of corrosion observed on bridges.It demonstrates the difficulties in maintaining old bridges using two case studies. 展开更多
关键词 CORROSION MANAGEMENT AGING steel BRIDGES cellular box CAST iron
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EXPERIMENTAL STUDY ON ELASTIC-PLASTIC CONTROLLING DESIGN FOR BOX STEEL STRUCTURES
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作者 Zhu Shishun Zhao Dingxuan Gong Kaijun (Jilin University of Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1996年第3期221-224,共1页
The principle of increasing structural loading abillity by the using of elastic-plastic con- trolling design, which can make steel reach a highcr yield slrength through controlling undue strains produced in loaded box... The principle of increasing structural loading abillity by the using of elastic-plastic con- trolling design, which can make steel reach a highcr yield slrength through controlling undue strains produced in loaded box steel structures and no damager to the static mechanical properties of the used materials, is dealt with under the guarantee of strength, rigidity, and stability. A new idea of elastic--plastic controlling design, which is mainly based on the elastic-plastic theory and experi- mental results and is different from the current design which is mainly based handbooks and design- er' s experience, is established. That is: the loading time and its effect on loaded structures are con- sidered, and the potential strength in used matcrials is fully utilized through the controlling of struc- tural strains in design. By the using of this design method, the weight and cost of box structures will be reduced in large amount. 展开更多
关键词 box steel structure Elastic-plastic design Controlling design
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考虑风-温耦合的钢箱梁外形对温度效应影响研究
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作者 黄旭 何佳骏 +2 位作者 丁文龙 朱金 李永乐 《重庆交通大学学报(自然科学版)》 北大核心 2025年第1期33-42,共10页
为了准确分析钢箱梁外形对截面温度特性的影响规律,提出了一种考虑钢箱梁周围局部风场与温度场相互作用的有限元分析方法,采用折减系数k来建立钢箱梁周围热边界层高度处风速U_(a)与远处气象站实测风速U的对应关系,对比分析了是否考虑风... 为了准确分析钢箱梁外形对截面温度特性的影响规律,提出了一种考虑钢箱梁周围局部风场与温度场相互作用的有限元分析方法,采用折减系数k来建立钢箱梁周围热边界层高度处风速U_(a)与远处气象站实测风速U的对应关系,对比分析了是否考虑风-温耦合对钢箱梁截面温度分布的影响,探讨了不同风嘴形式、截面宽高比、不同栏杆形式以及铺装厚度对钢箱梁截面温度分布的影响规律。研究表明:钢箱梁周围热边界层厚度处的风速U_(a)呈不均匀分布,且与远处风速U呈线性正相关;不考虑风-温耦合会明显低估钢箱梁顶板表面温度;钢箱梁截面的风嘴、截面宽高比、栏杆参数以及铺装厚度均会影响钢箱梁横截面的温度分布,改变截面的温差,因此,在桥梁的设计中,钢箱梁外形对截面温度分布的影响不可忽视。 展开更多
关键词 桥梁工程 钢箱梁 风-温耦合 数值模拟 热边界层
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基于无人搭载平台的钢箱梁内表面涂层病害及螺栓缺陷自动检测技术研究
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作者 麦权想 陈春雷 《涂料工业》 北大核心 2025年第2期57-64,共8页
针对钢箱梁内表面典型涂层病害及螺栓缺陷难以被快速感知、识别的问题,研发了具有一定普适性的大刚度多级折叠机械臂轨道机器人。基于涂层的典型病害分类、病害影响权重和涂层劣化等级评定,搭建了典型病害识别专家决策系统,并训练了多... 针对钢箱梁内表面典型涂层病害及螺栓缺陷难以被快速感知、识别的问题,研发了具有一定普适性的大刚度多级折叠机械臂轨道机器人。基于涂层的典型病害分类、病害影响权重和涂层劣化等级评定,搭建了典型病害识别专家决策系统,并训练了多尺度感受野网络。基于计算机视觉与深度学习技术提出了一种螺栓丢失与松动缺陷鲁棒性检测方法。结果表明:钢箱梁内表面涂层病害识别准确率为97%,分类准确率为90.3%;螺栓丢失缺陷识别准确率为99.0%,螺栓松动缺陷识别准确率为99.7%,螺栓缺陷检测时,透视拍摄角度不大于40°可减少对螺栓松紧度的误判。无人搭载平台的轨道机器人实现了对钢箱梁内表面涂层病害及螺栓缺陷的快速、高精度智能巡检。 展开更多
关键词 无人搭载平台 钢箱梁内表面 涂层病害 螺栓缺陷 自动检测
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