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Data-driven methods for predicting the representative temperature of bridge cable based on limited measured data
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作者 WANG Fen DAI Gong-lian +2 位作者 HE Chang-lin GE Hao RAO Hui-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3168-3186,共19页
Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai... Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges. 展开更多
关键词 cable-stayed bridges representative temperature gradient boosted regression trees(GBRT)method field test limited measured data
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Longitudinal forces of continuously welded track on high-speed railway cable-stayed bridge considering impact of adjacent bridges 被引量:32
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作者 戴公连 闫斌 《Journal of Central South University》 SCIE EI CAS 2012年第8期2348-2353,共6页
A proven beam-track contact model was used to analyze the track-structure interaction of CWR (continuously welded track) on bridge. Considering the impact of adjacent bridges, the tower-cable-track-beam-pier-pile fini... A proven beam-track contact model was used to analyze the track-structure interaction of CWR (continuously welded track) on bridge. Considering the impact of adjacent bridges, the tower-cable-track-beam-pier-pile finite element model of the cable-stayed bridge was established. Taking a bridge group including 40-32m simply-supported beam and (32+80+112)m single-tower cable-stayed bridge and 17-32m simply-supported beam on the Kunming-Shanghai high-speed railway as an example, the characteristics of CWR longitudinal force on the cable-stayed bridge were studied. It is shown that adjacent bridges must be considered in the calculation of the track expansion force and bending force on cable-stayed bridge. When the span amount of adjacent bridges is too numerous, it can be simplified as six spans; the fixed bearing of adjacent simply-supported beams should be placed on the side near the cable-stayed bridge; the track expansion device should be set at the bridge tower to reduce the track force near the bridge abutment. 展开更多
关键词 high-speed railway continuously welded track cable-stayed bridge simply-supported beam
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Effects of fundamental factors on coupled vibration of wind-rail vehicle-bridge system for long-span cable-stayed bridge 被引量:10
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作者 张明金 李永乐 汪斌 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1264-1272,共9页
In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundament... In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical example.Firstly,a finite element model is built for the long cable-stayed bridge.The deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss elements.Vehicles are modeled as mass-spring-damper systems.Rail irregularities and wind fluctuation are simulated in time domain by spectrum representation method.Then,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel tests.Eight vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square method.Finally,dynamic responses of the WVB system are analyzed in a series of cases.The results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great extent.The transverse forces of wheel axles mainly depend on the track irregularity.The displacements of the bridge are predominantly determined by the mean wind and restricted by its stiffness.And the accelerations of the bridge are enlarged after adding the fluctuating wind. 展开更多
关键词 wind-vehicle-bridge system coupled vibration long-span cable-stayed bridge fundamental factors
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Dynamic effect of heavy-haul train on seismic response of railway cable-stayed bridge 被引量:7
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作者 ZHU Zhi-hui GONG Wei +3 位作者 WANG Kun LIU Yu DAVIDSON Michael T JIANG Li-zhong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第7期1939-1955,共17页
This paper focuses on understanding and evaluating the dynamic effect of the heavy-haul train system on the seismic performance of a long-span railway bridge. A systematic study on the effect of heavy-haul trains on b... This paper focuses on understanding and evaluating the dynamic effect of the heavy-haul train system on the seismic performance of a long-span railway bridge. A systematic study on the effect of heavy-haul trains on bridge seismic response has been conducted, considering the influence of vehicle modeling strategies and dynamic characteristics of the seismic waves. For this purpose, the performance of a long-span cable-stayed railway bridge is assessed with stationary trains atop it, where the heavy-haul vehicles are modeled in two different ways: the multi-rigid body model with suspension system and additional mass model. Comparison of the bridge response in the presence or absence of the train system has been conducted, and the vehicle loading situation, which includes full-load and no-load, is also discussed. The result shows that during the earthquake, the peak moment of the main girder and peak stress of stay cables increase by 80% and by 40% in the presence of fully loaded heavy-haul trains, respectively. At the same time, a considerable decrease appears in the peak acceleration of the main girder. This proves the existence of the damping effect of the heavy-haul train system, and this effect is more obvious for the fully loaded vehicles. Finally, this paper proposes an efficient vehicle modeling method with 2 degrees of freedom(DOF) for simplifying the treatment of the train system in bridge seismic checking. 展开更多
关键词 train-bridge interaction heavy-haul train cable-stayed bridge EARTHQUAKE live load
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Numerical calculation on solar temperature field of a cable-stayed bridge with U-shaped section on high-speed railway 被引量:3
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作者 刘文硕 戴公连 饶少臣 《Journal of Central South University》 SCIE EI CAS 2014年第8期3345-3352,共8页
Based on transient temperature field theory of heat conduction, the solar temperature field calculation model of U-shape sectioned high-speed railway cable-stayed bridge under actions of concrete beams and ballast was... Based on transient temperature field theory of heat conduction, the solar temperature field calculation model of U-shape sectioned high-speed railway cable-stayed bridge under actions of concrete beams and ballast was established. Using parametric programming language, finite element calculation modules considering climate conditions, bridge site, structure dimension and material thermophysical properties were compiled. Six standard day cycles with the strongest yearly radiation among the bridge sites were selected for sectional solar temperature field calculation and temperature distributions under different temperature-sensitive parameters were compared. The results show that under the influence of sunshine, U-shape section of the beam shows obvious nonlinear distribution characteristics and the maximum cross-section temperature difference is more than 21℃; the ballast significantly reduces sunshine temperature difference of the beam and temperature peak of the bottom margin lags with the increase of ballast thickness; the maximum cross-section vertical temperature gradient appears in summer while large transverse temperature difference appears in winter. 展开更多
关键词 high-speed railway cable-stayed bridge U-shaped section solar temperature field thermal analysis
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Dynamic analysis and modal test of long-span cable-stayed bridge based on ambient excitation 被引量:3
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作者 陈常松 颜东煌 《Journal of Central South University of Technology》 EI 2007年第1期135-139,共5页
To study the stiffness distribution of girder and the method to identify modal parameters of cable-stayed bridge, a simplified dynamical finite element method model named three beams model was established for the gird... To study the stiffness distribution of girder and the method to identify modal parameters of cable-stayed bridge, a simplified dynamical finite element method model named three beams model was established for the girder with double ribs. Based on the simplified model four stiffness formulae were deduced according to Hamilton principle. These formulae reflect well the contribution of the flexural, shearing, free torsion and restricted torsion deformation, respectively. An identification method about modal parameters was put forward by combining method of peak value and power spectral density according to modal test under ambient excitation. The dynamic finite element method analysis and modal test were carried out in a long-span concrete cable-stayed bridge. The results show that the errors of frequencies between theoretical analysis and test results are less than 10% mostly, and the most important modal parameters for cable-stayed bridge are determined to be the longitudinal floating mode, the first vertical flexural mode and the first torsional mode, which demonstrate that the method of stiffness distribution for three beams model is accurate and method to identify modal parameters is effective under ambient excitation modal test. 展开更多
关键词 bridge engineering cable-stayed bridge dynamic finite element method ambient excitation modal test
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A new monitoring method of cable tension of cable-stayed bridge—fiber Bragg grating method 被引量:1
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作者 张戌社 杜彦良 宁辰校 《Journal of Central South University》 SCIE EI CAS 2005年第S2期261-263,共3页
A new on-line monitoring method based on fiber Bragg grating(FBG) for cable tension of cable-stayed bridge was introduced. The major structure of sensing head using in the test of cable tension is elastic annular. The... A new on-line monitoring method based on fiber Bragg grating(FBG) for cable tension of cable-stayed bridge was introduced. The major structure of sensing head using in the test of cable tension is elastic annular. The FBG is attached inflexibility to the exterior surface of annulus and form straight-through sensing head. Sensing head is installed between the anchor device and stow-board of funiculus holes of the cable-stayed bridge. Accompany with the change of the outside pressure, the Bragg center reflective wavelength of optical fiber grating changed correspondingly. According to this characteristic, through demodulating the Δλ, the value of the cable tension can be determined. The experiment results and the theory indicate that the test system has simple structure, good stability and linear,wide response capacity, and has no special request for tester, The measurement method for the test of cable tension is practical and effective. 展开更多
关键词 bridge cable tension fiber BRAGG GRATING
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Spatial gust impact analysis on safety and comfort of a train crossing cable-stayed bridge combining statistical method 被引量:2
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作者 ZHANG Yun-fei LI Li 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第8期2605-2620,共16页
In order to study the safety and the comfort of high-speed trains running on a single-tower cable-stayed bridge under spatial gust,a dynamic model of wind-train-bridge analysis model is built based on the autoregressi... In order to study the safety and the comfort of high-speed trains running on a single-tower cable-stayed bridge under spatial gust,a dynamic model of wind-train-bridge analysis model is built based on the autoregressive method,the multi-body dynamics method and the finite element method.On this basis,the influence of spatial gust model loading,the suspension parameters change,wind attack angle and speed on the train-bridge system are analyzed by combining the time/frequency domain analysis and statistical methods.The results show that the spatial gust environment is one of the most important factors affecting safety and comfort and can make the calculation result tend to be conservative and more conducive.The response changes caused by K_(py),K_(px)and K_(sx)changes are nearly linear,while Ksy shows nonlinear characteristics and the most sensitivity.Wind attack angle at 75°and 90°has the greatest influence on the vehicle-bridge system.For ride comfort index,when pre-set wind speed(α=75°)reaches 20 m/s,the vertical acceleration firstly exceeds the limit value;when wind speed(α=90°)reaches 21.5 m/s,the lateral acceleration firstly exceeds the limit value,and the ride comfort of the vehicle cannot be guaranteed.For running safety index,when pre-set wind speed(α=75°)reaches 24.6 m/s,the wheel unloading coefficient firstly exceeds the limit;when pre-set wind speed(α=90°)reaches 24.5 m/s,the derailment coefficient firstly exceeds the limit,and the running safety cannot be guaranteed.The results can provide a suitable reference for the safe and stable operation of trains on the bridge. 展开更多
关键词 wind-train-bridge dynamic system high-speed train crosswind environment single-tower cable-stayed bridge running safety running stability
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Determination of initial cable force of cantilever casting concrete arch bridge using stress balance and influence matrix methods 被引量:10
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作者 TIAN Zhong-chu PENG Wen-ping +2 位作者 ZHANG Jian-ren JIANG Tian-yong DENG Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第11期3140-3155,共16页
Cantilever casting concrete arch bridge using form traveller has a broad application prospect.However,it is difficult to obtain reasonable initial cable force in construction stage.In this study,stress balance and inf... Cantilever casting concrete arch bridge using form traveller has a broad application prospect.However,it is difficult to obtain reasonable initial cable force in construction stage.In this study,stress balance and influence matrix methods were developed to determine the initial cable force of cantilever casting concrete arch bridge.The stress balance equation and influence matrix of arch rib critical section were established,and the buckle cable force range was determined by the allowable stress of arch rib critical section.Then a group of buckle cable forces were selected and substituted into the stress balance equation,and the reasonable initial buckle cable force was determined through iteration.Based on the principle of force balance,the initial anchor cable force was determined.In an engineering application example,it is shown that the stress balance and influence matrix methods for the determination of initial cable force are feasible and reliable.The initial cable forces of arch rib segments only need to be adjusted once in the corresponding construction process,which improves the working efficiency and reduces the construction risk.It is found that the methods have great advantages for determining initial cable force in cantilever casting construction process of concrete arch bridge. 展开更多
关键词 concrete arch bridge cantilever casting initial cable force stress balance method influence matrix method
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Controlling deflection of long steel I-shaped girder bridge using two V-shaped pre-tensioning cables 被引量:2
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作者 Fatemeh PARTOVI Nader FANAIE 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期566-577,共12页
Despite appropriate design of girder under bending and shear,the deflection of long steel girders usually exceeds the allowable range,and therefore the structural designers encounter challenges in this regard.Consider... Despite appropriate design of girder under bending and shear,the deflection of long steel girders usually exceeds the allowable range,and therefore the structural designers encounter challenges in this regard.Considering significant features of the cables,namely,low weight,small cross section,and high tensile strength,they are used in this research so as to control the deflection of long girder bridges,rather than increasing their heights.In this study,theoretical relations are developed to calculate the increase in pre-tensioning force of V-shaped steel cables under external loading as well as the deflection of steel girder bridges with V-shaped cables and different support conditions.To verify the theoretical relations,the steel girder bridge is modeled in the finite element ABAQUS software with different support conditions without cable and with V-shaped cables.The obtained results show that the theoretical relations can appropriately predict the deflection of girder bridge with V-shaped cables and different support conditions.In this study,the effects of the distance from support on the deflection of mid span are studied in both simply supported and fixed supported girder bridge so as to obtain the appropriate distance from support causing the minimum deflection. 展开更多
关键词 DEFLECTION steel bridge I-shaped girder V-shaped cable pre-tensioning least work
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Parameters of static response of carbon fiber reinforced polymer(CFRP) suspension cables
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作者 王立彬 吴勇 Mohammad Noori 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3123-3132,共10页
The feasibility of longer spans relies on the successful implementation of new high-strength light weight materials such as carbon fiber reinforced polymer(CFRP). First, a dimensionless equilibrium equation and the co... The feasibility of longer spans relies on the successful implementation of new high-strength light weight materials such as carbon fiber reinforced polymer(CFRP). First, a dimensionless equilibrium equation and the corresponding compatibility equation are established to develop the cable force equation and cable displacement governing equation for suspension cables, respectively. Subsequently, the inextensible cable case is introduced. The formula of the Irvine parameter is considered and its physical interpretation as well as its relationship with the chord gravity stiffness is presented. The influences on the increment of cable force and displacement by λ2 and load ratio p′ are analyzed, respectively. Based on these assumptions and the analytical formulations, a 2000 m span suspension cable is utilized as an example to verify the proposed formulation and the responses of the relative increment of cable force and cable displacement under symmetrical and asymmetrical loads are studied and presented. In each case, the deflections resulting from elastic elongation or solely due to geometrical displacement are analyzed for the lower elastic modulus CFRP. Finally, in comparison with steel cables, the influences on the cable force equation and the governing displacement equation by span and rise span ratio are analyzed. Moreover, the influences on the static performance of suspension bridge by span and sag ratios are also analyzed. The substantive characteristics of the static performance of super span CFRP suspension bridges are clarified and the superiority and the characteristics of CFRP cable structure are demonstrated analytically. 展开更多
关键词 suspension bridge carbon fiber reinforced polymer (CFRP) main cable steel suspension cable static response
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基于Dynamo的Revit-Midas/Civil斜拉桥模型信息转换 被引量:2
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作者 蔡金标 刘鸾翔 +2 位作者 冯倩 何欣 徐荣桥 《湖南大学学报(自然科学版)》 北大核心 2025年第1期132-138,共7页
BIM模型不支持有限元计算,且BIM模型与有限元分析模型数据交互困难,故BIM技术正向设计过程中存在建模效率低、模型修改困难等问题,无法做到BIM结构设计与有限元力学分析一体化,增加了结构模型建模与纠错成本.本文依托Revit和Midas/Civi... BIM模型不支持有限元计算,且BIM模型与有限元分析模型数据交互困难,故BIM技术正向设计过程中存在建模效率低、模型修改困难等问题,无法做到BIM结构设计与有限元力学分析一体化,增加了结构模型建模与纠错成本.本文依托Revit和Midas/Civil软件平台,在Dynamo环境下采用IronPython语言设计了一套Revit-Midas/Civil的模型信息转换程序.以博士大桥主桥为对象,通过程序自动实现:1)Revit模型桥梁构件分解、截面特性计算、拉索及梁塔弹性连接处理,并转换成适用于Midas/Civil的语言格式MCT文件,实现了Revit向Midas/Civil模型信息自动转换;2)将有限元计算结果反馈到Revit模型中,对作用效应信息按数值大小赋予渐变颜色,实现了在BIM模型中显示有限元分析结果的展示功能.本文程序可实现Revit-Midas/Civil模型信息转换,有效提高了BIM正向应用效率,弥补了BIM技术在桥梁结构分析方面的不足. 展开更多
关键词 斜拉桥 模型转换 Dynamo混合编程 REVIT MIDAS/CIVIL
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基于GA-LSTM的桥梁缆索腐蚀钢丝力学性能预测模型 被引量:5
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作者 缪长青 吕悦凯 万春风 《东南大学学报(自然科学版)》 北大核心 2025年第1期140-145,共6页
为了精准捕捉桥梁缆索腐蚀钢丝的时变规律并预测其力学性能,开发了一种基于遗传算法(genetic algorithm, GA)优化的长短期记忆(long short-term memory, LSTM)神经网络模型。该模型利用GA依次优化LSTM模型的迭代次数、隐藏层层数、神经... 为了精准捕捉桥梁缆索腐蚀钢丝的时变规律并预测其力学性能,开发了一种基于遗传算法(genetic algorithm, GA)优化的长短期记忆(long short-term memory, LSTM)神经网络模型。该模型利用GA依次优化LSTM模型的迭代次数、隐藏层层数、神经元数量、窗口大小4个超参数,以预测不同腐蚀特征状态下钢丝的力学性能。将其与传统LSTM和GA-反向传播模型的预测结果进行比较。结果表明,GA-LSTM模型具有更高的预测精度和鲁棒性。在屈服强度与极限强度预测效果方面,均方根误差(root mean square error, RMSE)、平均绝对误差(mean absolute error, MAE)、决定系数分别提高约44%~61%、43%~57%、35%~92%。在屈服应变与极限应变预测效果方面,RMSE、MAE、决定系数分别提高约0~46%、7%~49%、12%~229%。所建立的模型可以作为一个有用的工具支持桥梁缆索腐蚀安全性评估工作。 展开更多
关键词 桥梁缆索腐蚀钢丝 力学性能预测 时序预测 神经网络 遗传算法 超参数优化
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基于无人机载激光雷达空间线形扫描的斜拉索索力测试 被引量:1
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作者 施洲 张同卓 +2 位作者 苏朋飞 朱颖 郭辉 《铁道学报》 北大核心 2025年第2期172-180,共9页
为提升大跨度斜拉桥斜拉索索力测试的效率和精度,提出一种基于机载激光雷达非接触式斜拉索线形扫描的索力测量方法——线形法。利用高差和空间聚类法从点云提取斜拉索实测线形,结合索参数、索力理论公式和非线性有限元分析,提出索力推... 为提升大跨度斜拉桥斜拉索索力测试的效率和精度,提出一种基于机载激光雷达非接触式斜拉索线形扫描的索力测量方法——线形法。利用高差和空间聚类法从点云提取斜拉索实测线形,结合索参数、索力理论公式和非线性有限元分析,提出索力推算的公式法和有限元法,两种方法相互校核、平均实现线形法索力测试。依托主跨672 m的鳊鱼洲长江大桥现场静载试验,分别采用线形法和频率法进行索力测试,开展验证与对比分析。结果表明:线形法、频率法索力测试结果最大误差分别为2.6%、5.8%,线形法显著提高了效率和精度。索力误差与实测弧垂误差成正比,弧垂误差对长索索力测试误差影响较小。索力误差随索长增加而减小:索长为200 m时,索力相对误差为6.2%,误差明显;当索长300 m时,索力相对误差降低至2.9%。线形法索力测试适用于长度为300 m以上的长索索力测试,并可通过多次测试平均、提升斜拉索实测点云处理精度等措施提高索力测试精度。 展开更多
关键词 斜拉桥 斜拉索 索力测试 线形法 三维扫描 误差分析
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珠肇高铁西江特大桥主桥总体设计 被引量:1
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作者 王斌 《世界桥梁》 北大核心 2025年第1期15-21,共7页
珠肇高铁西江特大桥主桥为(70+148+2×435+148+70)m三塔斜拉桥,采用中塔设置固定支座、边塔设置纵向活动支座的支座体系,在中、边塔处均设置纵向液压阻尼器,辅助墩、边墩处设置E型钢阻尼器,并设置2对中塔加强索以提高桥梁刚度。主... 珠肇高铁西江特大桥主桥为(70+148+2×435+148+70)m三塔斜拉桥,采用中塔设置固定支座、边塔设置纵向活动支座的支座体系,在中、边塔处均设置纵向液压阻尼器,辅助墩、边墩处设置E型钢阻尼器,并设置2对中塔加强索以提高桥梁刚度。主梁采用钢-混组合梁,钢结构采用槽形截面,桥面板采用混凝土板,负弯矩较大的主梁区段采用顶、底板双组合截面以改善主梁应力状态。辅助墩两侧共58 m范围内钢结构与混凝土桥面板采用缓粘结剪力钉连接,桥面板采用超高性能混凝土(UHPC)+钢筋混凝土(RC)组合结构,以提高桥面板抗裂性能。采用H形桥塔,由上、中、下塔柱和上、下横梁组成,桥面以上塔高与主跨跨径比值为1/3.69,桥塔及桥墩均采用钻孔灌注桩基础;斜拉索采用双索面扇形布置,全桥设置102对平行钢丝拉索以及2对中塔加强索。该桥结构验算结果表明:桥梁具有合理的刚度、良好的轨道平顺性、气动稳定性及抗风性能,能够满足高速列车运行要求。 展开更多
关键词 铁路桥 三塔斜拉桥 钢-混凝土组合梁 中塔加强索 缓粘结剪力钉 UHPC+RC组合桥面板 桥梁设计
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斜拉桥钢桥面板挖孔细节群的数字畸变疲劳试验 被引量:1
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作者 王春生 许璐巍 李璞玉 《东南大学学报(自然科学版)》 北大核心 2025年第1期66-77,共12页
为研究斜拉桥钢桥面板横隔板挖孔细节群的畸变疲劳机理,考虑疲劳应力、焊接残余应力、焊接缺陷等多场耦合作用,建立了斜拉桥全桥足尺数字疲劳孪生模型,实现了钢桥面板典型细节群的数字畸变疲劳试验与模拟。焊接数字孪生模拟时,采用与单... 为研究斜拉桥钢桥面板横隔板挖孔细节群的畸变疲劳机理,考虑疲劳应力、焊接残余应力、焊接缺陷等多场耦合作用,建立了斜拉桥全桥足尺数字疲劳孪生模型,实现了钢桥面板典型细节群的数字畸变疲劳试验与模拟。焊接数字孪生模拟时,采用与单元温度相关联的热对流参数表达,可显著改善焊接温度场和残余应力场模拟准确度。数字畸变疲劳试验与模拟结果表明,横隔板挖孔细节群的畸变疲劳裂纹尖端等效应力强度因子幅均大于门槛值,该细节群初始裂纹在运营卡车荷载作用下易于扩展。应变能释放率分析结果表明,横隔板挖孔细节群的畸变疲劳裂纹均是以Ⅰ型裂纹为主导的Ⅰ-Ⅱ-Ⅲ型复合型裂纹,扩展全过程3种类型裂纹耦合特征显著。该研究成果可为斜拉桥钢桥面板抗疲劳设计与维护提供依据。 展开更多
关键词 桥梁工程 斜拉桥 钢桥面板 畸变疲劳 数字疲劳试验 复合型裂纹 累积应变能释放率
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深中大桥主缆智慧索股研制与工程应用
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作者 张鸿 杨建平 +2 位作者 范典 金芳 王蔚 《桥梁建设》 北大核心 2025年第2期1-9,共9页
深中通道深中大桥为主跨1 666 m的全飘浮钢箱梁双塔悬索桥,设2根主缆,单根主缆由199股预制平行钢丝索股组成,单根索股由127根φ6.0 mm高强锌铝镁多元合金镀层钢丝和锚具等组成。为实现该桥主缆全域范围内的温、湿度密集监测,提升主缆健... 深中通道深中大桥为主跨1 666 m的全飘浮钢箱梁双塔悬索桥,设2根主缆,单根主缆由199股预制平行钢丝索股组成,单根索股由127根φ6.0 mm高强锌铝镁多元合金镀层钢丝和锚具等组成。为实现该桥主缆全域范围内的温、湿度密集监测,提升主缆健康监测水平,提出通长内嵌温、湿度弱光栅阵列传感光纤的3 000米级智慧索股新结构,开展弱光栅阵列湿度传感光纤、光纤封装光缆结构及智慧索股研制,在该桥下游主缆中安装4根3 006 m长智慧索股,并对智慧索股服役状态进行了长达2年的跟踪监测。结果表明:研制的智慧索股新结构可保证其内传感光纤在制造和现场安装应用全过程的存活与工作,智慧索股实现了主缆全域温、湿度的密集监测,该结构为悬索桥主缆全域的温、湿度监测提供了全新的技术手段。 展开更多
关键词 悬索桥 弱光栅阵列传感光纤 温度 湿度 光缆 智慧索股 工程应用
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空间缆悬索桥主梁吊装过程分析
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作者 陈铭 万田保 王波 《世界桥梁》 北大核心 2025年第3期96-101,共6页
为研究利用独立悬挂式缆载吊机进行空间缆悬索桥主梁吊装的可行性,以某空间缆悬索桥为背景,采用有限元法对采用该吊机的主梁吊装过程展开分析。有限元模拟时,采用线性弹簧和仅受压弹簧协同模拟主梁节段间的临时连接;通过增加梁单元引入... 为研究利用独立悬挂式缆载吊机进行空间缆悬索桥主梁吊装的可行性,以某空间缆悬索桥为背景,采用有限元法对采用该吊机的主梁吊装过程展开分析。有限元模拟时,采用线性弹簧和仅受压弹簧协同模拟主梁节段间的临时连接;通过增加梁单元引入主缆弯扭刚度和索夹抗弯刚度;基于主缆弯扭刚度限值开展多参数分析并通过关键响应包络进行结果评估。结果表明:在梁段吊装过程中,结构面临吊索弯折、主缆扭转、主缆弯折、主梁合龙难度大、节段临时连接力大等问题,采用2种梁段吊装顺序结构关键响应存在一定差异,采用相关工程措施后均可行。该量化评估方法亦可为主缆间横向顶撑或对拉装置设置的必要性和数量提供决策依据。 展开更多
关键词 空间缆悬索桥 独立悬挂式缆载吊机 吊索弯折 主缆扭转 主缆弯折 弯扭刚度 成桥状态 有限元法
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基于准2N+1电平调制的长电缆馈电级联H桥电驱系统过电压振荡抑制
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作者 朱艳萍 张赛宇 +3 位作者 张敏 赵巍 李昕 孙孝峰 《中国电机工程学报》 北大核心 2025年第10期4018-4033,I0038,共17页
对于长电缆馈电的中压电驱系统,当电机浪涌阻抗和电缆特征阻抗不匹配时,变频器产生的高频脉宽调制脉冲电压会在电机端发生反射,导致严重的过电压振荡,从而加速电机绕组和电缆的绝缘老化甚至破坏绝缘。目前主流的无源滤波器抑制方案存在... 对于长电缆馈电的中压电驱系统,当电机浪涌阻抗和电缆特征阻抗不匹配时,变频器产生的高频脉宽调制脉冲电压会在电机端发生反射,导致严重的过电压振荡,从而加速电机绕组和电缆的绝缘老化甚至破坏绝缘。目前主流的无源滤波器抑制方案存在体积巨大,损耗高,额外成本以及灵活性差的缺点。为此,针对级联H桥变频器提出一种准2N+1电平调制方案,其抑制原理是通过在变频器输出电压的每个上升/下降沿插入固定宽度的准电平从而消除电缆上的反射波,达到抑制过电压振荡的目的。最后,通过仿真及实验验证所提出方案的有效性,与现有的抑制方案相比,系统的效率显著提升,并且无需附加任何组件,避免了额外的体积和成本。 展开更多
关键词 长电缆 反射 过电压振荡 电机驱动 级联H桥
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洪奇沥公铁两用大桥主桥边跨组合梁设计及施工方案研究
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作者 刘振标 夏正春 +3 位作者 印涛 胡方杰 徐伟伟 姜洪劲 《铁道标准设计》 北大核心 2025年第5期95-102,共8页
洪奇沥公铁两用大桥是新建深圳至江门铁路的关键性控制工程,公铁分层布置,上层为8车道城市快速路,下层为4线铁路。主桥采用(3×100+808+3×100) m超短边跨钢混箱-桁组合梁斜拉桥,一跨跨越洪奇沥水道,无工程先例可借鉴。结合建... 洪奇沥公铁两用大桥是新建深圳至江门铁路的关键性控制工程,公铁分层布置,上层为8车道城市快速路,下层为4线铁路。主桥采用(3×100+808+3×100) m超短边跨钢混箱-桁组合梁斜拉桥,一跨跨越洪奇沥水道,无工程先例可借鉴。结合建设条件、结构特点以及技术经济性,对边跨主梁结构设计及施工方案展开研究。结果表明,主梁采用矩形钢管混凝土叠合板-桁组合梁,将结构受力和对拉索的锚固压重融于一体,并在边跨施工阶段充分发挥连续钢桁梁自身高承载力特性和叠合板现浇层以预制板为底模的优势,节省模板和临时工程,具有显著的经济效益;钢桁梁采用“纵向分段横向分块安装+多点步履式顶推”的施工方案,有效解决超宽、超高钢桁梁水运运输受通航条件限制的难题,并适应边跨位于岸上的大吨位钢梁架设;边跨施工采用部分支撑临时墩方案,临时墩反力较完全支撑临时墩方案减小46.2%,临时工程量少,并且避免了不设临时墩方案中主跨架设对边跨混凝土浇筑的扰动影响,叠合板-桁组合梁施工质量高;现浇混凝土采用“先受压区后受拉区、先管内后管外”的分段浇筑方案,较一次浇筑方案,上、下层桥面板最大名义拉应力分别减小81.8%、76.0%,有效改善混凝土结构受力。 展开更多
关键词 公铁合建桥 斜拉桥 叠合板-桁组合梁 结构设计 施工方案
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