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大跨度简支钢桁梁桥车-桥耦合振动影响因素分析
Analysis of the Influencing Factors of Train-bridge Coupled Vibration of a Large-span Simply-supported Steel Truss Railway Bridge
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陈敦,王根会,穆彦虎,彭惠
- , 2017, DOI: 10.3969/j.issn.1000-0844.2017.02.0205
Abstract: 以黄韩侯铁路新黄河特大桥156 m简支钢桁梁桥作为工程背景,建立车辆动力模型、桥梁有限元模型并考虑轮轨关系,以蛇形运动和轨道不平顺作为系统的自激激励源,利用大型有限元软件ANSYS以及UM(Universal Mechanism)动力学分析软件联合进行仿真分析。从桥梁结构的桥门架、宽跨比、曲线钢桁梁桥和车辆系统的轨道不平顺以及货车编组角度出发,研究大跨度简支钢桁梁桥车-桥耦合振动的影响因素。经过计算分析得出:钢桁梁桥桥门架对桥梁跨中加速度影响较大;曲线钢桁梁桥随着线路半径的增大,各车辆动力响应参数逐渐变小,轮轨力受到影响;钢桁梁桥宽跨比的增加使得横向刚度随之增加,桥梁横向振动变小;各项车辆动力响应均随着轨道情况变差而总体呈现逐渐增大趋势,车辆安全性、舒适性和平稳性指标逐渐变差;全列空车编组和空重混编对钢桁梁车-桥耦合系统是不利的编组形式,实际情况中应该避免。
With the rapid development of rail transportation in China, high-speed and heavy-load railways have become the trend of development in this field. In such systems, it is important to consider the interaction process between the train and the bridge, along with the influential factors, when a train passes through a bridge. In this paper, a 156-m long simply-supported steel truss bridge of the Huang Han-hou New Yellow River Railway is taken as an example. A dynamic model of the train-bridge was constructed considering a wheel-rail relationship. Serpentine movements and track irregularity were used as self-excited excitation sources of the train-bridge system. The finite element software ANSYS and UM (Universal Mechanism) were used to simulate the train-bridge coupled vibrations. The influence of the bridge structure of the portal frame, wide-span ratio, curve of the steel truss and track irregularity, as well as the marshaling coaches on the train-bridge coupled vibrations were discussed with the numerical simulations. The results showed that the gantry of the steel truss bridge had greater influence on the acceleration. As the line radius of the curved steel truss bridge increased, the dynamic responses of the train became smaller, thus affecting wheel-rail force. Moreover, with increasing wide-span ratio, the lateral stiffness of the bridge increases, and the bridge lateral vibration became smaller. When the track conditions became worse, the dynamic responses of the train increased considerably and the comfortable and stability worsened. The findings indicate that the full empty grouping and empty-weight mixed grouping schemes are harmful to the coupled system of a train-bridge, which should be avoided in practical operation.
双撑杆智能预应力钢桁梁承载性能参数分析
Parameter analysis of bearing capacity of smart prestressed steel truss with two struts
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徐伟炜,陈?琶?
- , 2016, DOI: 10.3969/j.issn.1001-0505.2016.04.026
Abstract: 运用ANSYS软件计算分析了双撑杆智能预应力钢桁梁跨中挠度约束范围、杆件应力约束范围、钢桁梁跨度、撑杆数量以及荷载形式5个因素对双撑杆智能预应力钢桁梁承载性能的影响,并将相同约束条件下双撑杆智能预应力钢桁梁与普通预应力钢桁梁的承载性能进行了对比.结果表明:挠度约束范围越小、应力约束范围越宽、钢桁梁跨度越大,则智能预应力钢桁梁与普通预应力钢桁梁的最大约束承载力之比就越大;双撑杆智能预应力钢桁梁的承载性能优于单撑杆智能预应力钢桁梁;智能预应力钢桁梁在逐次增多荷载工况下的承载性能优于移动集中荷载工况下的承载性能.
The impacts of the deflection constrain range, stress constrain range, truss span, strut number and load form on the bearing capacity of a smart prestressed steel truss with two struts were analyzed by using the ANSYS software, and the bearing capacity is compared with that of the conventional prestressed truss under the same constrain conditions. The results show that with the smaller deflection constrain range, wider stress constrain range, and longer truss span, the ratio of the constrain bearing capacity of the smart prestressed truss to that of the conventional prestressed truss is higher. The bearing capacity of the smart prestressed steel truss with two struts is better than that with single strut. The bearing capacity of the smart prestressed steel truss under the successive incremental load condition is better than that under concentrated load condition
中等跨径装配式矩形钢管混凝土组合桁梁桥设计
Design of mid-span fabricated RCFST composite truss bridge
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刘彬,刘永健,周绪红,李周,王康宁
- , 2017,
Abstract: 优化了传统混凝土箱梁腹板与底板,提出了装配式桥梁新型结构形式――矩形钢管混凝土组合桁梁桥,从总体设计、主桁选型、横断面选型、桥面板选型、杆件选型、节点选型与连接构造方面介绍了其结构设计优化过程; 从桥梁的静力性能与地震响应、桥面板的有效宽度与负弯矩区力学性能方面对矩形钢管混凝土组合桁梁桥进行了有限元分析,并将部分组合技术应用到负弯矩区桥面板连接件的设计中; 从技术性与经济性角度将矩形钢管混凝土组合桁梁桥与预应力混凝土箱梁桥进行了工程量和施工便捷性对比。研究结果表明:矩形钢管混凝土组合桁梁桥结构选型符合桥梁预制装配、快速建造的工业化要求,主桁各杆件受力明确,受力形态主要为轴向拉、压力; 负弯矩区桥面板有效宽度系数为0.899; 采用部分组合技术可使桥面板轴向拉力下降75.3%,有效地提高了桥面板的抗裂性能; 矩形钢管混凝土组合桁梁桥初始输入地震力占同等跨度预应力混凝土箱梁桥的58.9%,说明矩形钢管混凝土组合桁梁桥具有良好的抗震性能; 钢材用量、混凝土用量、上部结构质量与预应力混凝土箱梁桥的比值分别为1.241、0.485、0.575,说明矩形钢管混凝土组合桁梁桥结构轻巧,材料利用率高,工程造价低,具有经济优势。
The webs and bottom slabs of traditional concrete box girder were optimized, and a new structural type of fabricated bridge named RCFST(rectangular concrete filled steel tubular)composite truss bridge was proposed. The structure design optimization procedure was introduced from the aspects of general design, main truss selection, cross section selection, bridge deck slab selection, member bar selection, joint selection and connection structure. The RCFST composite truss bridge was analyzed by finite element method from the static mechanical property and seismic response of the bridge, and the effective width and mechanical property of bridge deck slab in the negative moment zone of the slab. The partial composite technique was also used in the design of bridge deck slab connector in the negative moment zone. From the technicality and economy, the RCFST composite truss bridge was compared with the prestressed concrete box girder bridge in terms of engineering quantity and construction convenience. Analysis result shows that the selection of RCFST composite truss bridge structure meets the industrialization requirement of bridge's prefabrication and accelerated construction, and the member bars of main truss with clear force-bearing states mainly carry axial tensions and pressures. The effective width coefficient of bridge deck slab in the negative moment zone is 0.899. The axial tension of bridge deck slab decreases by 75.3% using the partial composite technique, which effectively improves the anti-crack ability of bridge deck slab. The initial input earthquake load of RCFST composite truss bridge accounts for 58.9% of the load of prestressed concrete box girder bridge with the same span, which indicates RCFST composite truss bridge has good anti-seismic property. The ratios of steel quantity, concrete quantity, and superstructure self-weight of RCFST composite truss bridge to prestressed concrete box girder bridge are 1.241, 0.485 and 0.575, respectively, which indicates the RCFST composite truss bridge has good economic advantages, such as
框桁式复合墙体抗震性能试验及有限元分析 Seismic performance test and finite element analysis of frame truss composite wall
Seismic performance test and finite element analysis of frame truss composite wall
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雍馨,杜保平,李哲,李晓蕾
- , 2018, DOI: 10.7511/jslx20170712001
Abstract: 提出一种新型框桁式复合墙,由钢筋混凝土外框和内部桁式杆件构成。为了研究其抗震性能,按1:2的缩尺比例初步设计和制作了3个单片框桁式复合墙体,进行了拟静力试验,并采用ABAQUS软件建立了有限元非线性分析模型,重点分析了轴压比、混凝土强度、箍筋配箍率及纵筋配筋率对其承载力和延性的影响。结果表明,墙体桁杆先于外框墙肢产生变形和破坏,最终在墙肢底部与桁杆围成的三角形部位由于弯矩值达到极限而发生破坏,破坏顺序明确,可达到多级耗能的目的;三个试件的延性系数均小于2.5,各试件延性系数的不同说明桁杆截面形式是影响墙体承载力的重要因素;随着轴压比、混凝土强度和纵筋配筋率的增大,试件承载力有不同程度的提高,试件的延性系数随轴压比和纵筋配筋率的增大而减小,随混凝土强度的增大而增大;箍筋配箍率对试件荷载-位移曲线、承载力和延性系数的影响很小;各因素对各项抗震性能的影响程度不同。
A new type of frame-truss composite walls composed of reinforced concrete frames and internal truss members is proposed in this paper.In order to study the seismic performance,3 units of frame truss composite walls according to the reduced scale of 1:2 were preliminarily designed and manufactured,a pseudo-static test was carried out,and a nonlinear finite element analysis model was established by using ABAQUS software.The influence of bearing capacity and ductility by the axial compression ratio,concrete strength,stirrup ratio and longitudinal reinforcement ratio was analyzed.The results show that the truss was deformed and destroyed prior to the outer wall,and finally ultimate destruction occured at the location of the triangle formed the bottom of the wall and the truss when the bending moment reaches the limit capacity,the sequence of damage is clear.The purpose of multistage energy dissipation can be achieved.The ductility coefficient of three specimens were less than 2.5,the difference of ductility coefficient between three specimens shows that the shape of the truss cross section is an important factor affecting the bearing capacity of the wall.With the increase of axial compression ratio,concrete strength and longitudinal reinforcement ratio,the bearing capacity of specimens increases to different degrees,the ductility coefficient of specimens decreases with the increase of axial compression ratio and longitudinal reinforcement ratio,but increases with the increase of concrete strength.In addition,the effect of reinforcement ratio on load-displacement curve,bearing capacity and ductility coefficient of concrete is very minor;each factor has different influence on the seismic performance.
曲线异形双层人行钢桁梁力学性能研究
Study on the mechanical behavior of specially-shaped steel truss girder with double pedestrian
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常柱刚,张红显
CHANG Zhugang
, ZHANG Hongxian

- , 2018,
Abstract: 为了研究曲线异形双层人行钢桁梁力学性能,依托国内首座双层人行钢桁梁,以有限元法为基础,借助结构分析软件Midas civil建立异形钢桁梁数值模型,计算双层人行桥各荷载组合作用下结构各部件应力和结构纵、横向挠度,并结合异形双层钢桁梁特点,计算结构稳定系数及支反力,同时研究人字叉对结构稳定及支反力的影响。研究结果表明:最不利荷载组合作用下,结构最大拉、压应力均发生在斜腹杆位置,由最不利荷载工况引起的结构最大纵向挠度为L/1 340,结构挠度及各部件应力满足规范要求,上层满布人群荷载时结构稳定性系数最小,设置人字叉时,结构稳定系数变化较小,主要削弱边支点支反力峰值,起平衡结构支反力的作用。
Taking the first domestic double row steel truss footbridge as an engineering example, this paper studied the mechanical behavior of specially-shaped steel truss girder with double pedestrian. Based on the finite element method, the numerical model of the special-shaped steel truss was established by means of structural analysis software Midas civil. The longitudinal and transverse deflections of each member of the structure under the action of different loads were calculated. Combining with the characteristics of the double row steel truss beam, the structural stability coefficient and the fulcrum reaction force were calculated. The result shows that under the most unfavorable load combination, the maximum tensile stress and compressive stress of the structure occur at the position of the inclined bar, and the maximum longitudinal deflection of the structure is L/1 340. Structural deflection and stress of components meet the specification requirements. The structural stability coefficient is minimum when the upper layer is full of crowd load. When the herringbone fork is set, the structural stability coefficient changes little, which mainly weakens the peak of the reaction force of the side fulcrum bearing
双塔钢桁斜拉桥结构强健性计算方法
Calculating method of structural robustness of double-tower cable-stayed bridge with steel truss girder
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郑小博,,,贺拴海,,
- , 2017,
Abstract: 为了确保双塔钢桁斜拉桥的结构强健性,依托新疆果子沟大桥,基于现场结构试验,开发了全方位多点温度补偿系统,测量了特定加载工况下钢桁主梁应变、挠度与斜拉索索力增量,确定了钢桁主梁与斜拉索重要构件的具体位置; 基于试验结果,借鉴广义结构刚度理论,采用桥梁结构有限元模型分析了斜拉桥弦杆与斜拉索的重要性系数,研究了桥梁最不利破坏模型。研究结果表明:各工况下钢桁主梁应变实测数据规律性较好,钢桁主梁应变与挠度的实测值与理论计算值的比值小于1.0,表明主梁承载能力与抗变形能力符合设计要求,具有足够的安全储备; 主梁在各工况下的最大挠度均发生在中跨跨中,达到237 mm,具有较强抗变形能力; 斜拉索索力增量实测值与理论计算值的比值小于1.0,表明斜拉索具有一定的安全储备; 钢桁主梁控制截面处弦杆与特定斜拉索为重要性系数较高的构件,斜拉索的重要性系数大于弦杆的重要性系数,其中弦杆的重要性系数分布集中于主塔附近与中跨跨中; 通过斜拉索重要性系数的分布可知单根斜拉索的破损不会造成整体结构的坍塌,但多于2根斜拉索失效可能会导致整体结构的连续倒塌; 主跨最长斜拉索和中跨跨中、边跨支座处与靠近主塔处弦杆失效对于整体结构较为不利。
In order to ensure the structural robustness of double-tower cable-stayed bridge with steel truss girder, all-round multipoint temperature compensation system was developed based on the Xinjiang Guozigou Bridge and field structure test. The strain, deflection and cable force increment of steel truss girder were measured under specific loading conditions, and the specific locations of important components of steel truss girder and stay cables were determined. Based on the experimental result and the generalized structural stiffness theory, the robustness importance factors of cables and chords were analyzed by using the finite element model of bridge structure, and the most critical failure model of cable-stayed bridge was studied. Study result shows that the regularities of the measured data of steel truss girder strain under various working conditions are good, and the ratios of measured and theoretical values of strain and deflection are less than 1.0, so the bearing capacity and anti-deformability of steel truss girder meet the design requirements, and the girder has sufficient safety reserve. The maximum deflection of the girder under each loading case is at the middle of main span and can reach to 237 mm, so the girder has strong anti-deformability. Because the ratios of the measured increments of cable force and theoretical values are less than 1.0, the stay cables have safety reserve to a certain extent. The chords at control sections and the specific stay cables of the girder have higher importance factors, the factors of stay cables are larger than the values of the chords, and the importance factor distributions of the chords concentrate in the middle of main span and nearby areas of main pylons. According to the distributions of importance factors of stay cables, the damage of single stay cable can causes the collapse of overall structure, and the failures of more than two stay cables will result in the progressive collapse of entire structure. The failures of the longest stay cable of main span and the chords at its middle, as well as
DAMAGE IDENTIFICATION AND DIAGNOSIS OF EXISTING STEEL TRUSS BRIDGE
既有钢桁梁桥损伤识别与诊断方法研究

WANG Genhui,ZHU Shangqing,
王根会
,朱尚清

力学与实践 , 2007,
Abstract: Based on the theory of structural dynamics,the damage identification and diagnosis of existing steel truss bridges is studied.With the natural frequency as the characteristic parameter and using method of BP neural network and the MATLAB,the damage identification and diagnosis is analysed and a complete flow chart for the bridge damage identification and diagnose is proposed.With the method,the damage process of a steel truss bridge is numerically stimulated.
洞庭湖铁路斜拉桥先箱后桁两步施工法研究
Study of two step construction method of installing the box girder first and then installing the truss members of Dongting Lake railway cable-stayed bridge
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张晔芝,杨毅,易伦雄
ZHANG Yezhi
, YANG Yi, YI Lunxiong

- , 2018,
Abstract: 针对洞庭湖铁路斜拉桥的结构特点,提出先箱后桁两步拼装的新方法,并对该法提出2个施工方案并进行有限元模拟和对比分析,定量研究箱、桁由于施工不同步引起的变形不协调问题。根据计算结果推荐方案2,该方案能将箱、桁变形的不协调控制在螺栓与螺栓孔间隙的可调范围内,而且可以在桥面上多点分段拼装主桁杆件以加快施工进度。该方案已被成功应用于该桥的施工并取得了很好的效果。
According to the structure characteristics of Dongting Lake railway cable-stayed bridge, a new method of two-step construction was proposed, in which the box girder was fabricated first and then the steel trusses were installed on the box girder deck. This method not only overcomes the shortages of separate installation, such as too many components and too heavy aerial work on the site, but also overcomes the shortcomings of segment installation such as large size and large weight of the segment, too many splice joints, and difficulties of installation, hoisting and transfer of the segment. Two plans of the new method were presented, and their construction processes were simulated. The nonconforming deformation of the box girder and the truss bars were studied quantitatively using finite element method. According to the results, plan 2 was recommended, which can control the nonconforming deformation of the box girder and the truss bars within the adjustable range of the gap between the bolt and the bolt hole. Furthermore, the installation of the truss bars upon the box girder can be divided into many parts along the length of the bridge. In these parts, the truss bars can be installed at the same time to speed up the construction process. Plan 2 has been recommended and successfully used in the construction of the bridge and obtained excellent results
大跨度钢桁拱桥关键节点受力特性及优化研究
Mechanical characteristic and optimization study on key joint of long span steel truss arch bridge
 [PDF]

黄勇军
- , 2018,
Abstract: 横琴二桥是国内跨度最大、桥面最宽的公路钢桁架拱桥,孔跨布置为:100+400+100=600 m。桥下拱肋与下弦杆交汇处的节点(E9节点)采用焊接整体节点,节点板将主桁相关杆件和桥面纵、横梁连成一体,各构件内部加劲肋众多,形式、尺寸多样,节点的结构构造和受力状态复杂。在全桥空间有限元分析的基础上,选取具有代表性的E9节点和2个最不利的主力组合工况,完成局部精细有限元分析。研究结果表明:2个工况下E9节点各相关杆件绝大部分区域应力水平较低,Mises 等效应力小于200 MPa,局部区域应力集中程度较严重,应力水平超出了弹性范围。针对拱内下弦杆变截面处出现的高应力区域的情况提出改善措施,建议在该位置增设一道环形横隔板,该方案可不影响下弦杆内的柔性系杆通过。增设横隔板后,变截面处的应力集中现象得到明显改善,应力水平在弹性范围以内。
Hengqin second bridge is a highway steel truss arch bridge with the largest span and the widest deck in China. The span of the bridge is 100+400+100=600 m. The welded integral joint E9 was located at the junction of the lower arch rib and the lower chord. By using two connecting plates, the relevant truss bars and cross beam of the floor beam are welded as a whole. The internal structure construction of the joint is very complex. Many stiffening ribs of various kinds and scale are arranged inside every components. Refined finite element analysis is completed for the representative E9 joint and the two worst load cases of main loads combination based on 3D finite element analysis of the whole bridge. The results show that the stress level of most areas of the relevant components of E9 joint are not high, and their Mises equivalent stress is less than 200 MPa. However, 5 small regions exist where bear severe stress concentration are beyond yield stress. A circinate diaphragm is proposed to reduce the stress level of the varying section of the lower chord. This measure does not affect the work of flexible tied bars. The results of local refined finite element analysis show that stress concentration is solved and the material remains in the elastic state with diaphragm added
大跨铁路钢桁连续梁桥减隔震方案比较研究
Comparative Study on Seismic Mitigation and Isolation Schemes fora Long-span Railway Steel Truss Continuous Beam Bridge
 [PDF]

杨华平,钱永久,樊启武,黎璟,邵长江
- , 2017, DOI: 10.3969/j.issn.1000-0844.2017.06.1097
Abstract: 为研究适用于大跨铁路钢桁连续梁桥的减隔震方案及合理优化参数,以一座全长504 m的三跨铁路钢桁连续梁特大桥为工程背景,使用非线性结构分析软件SAP2000建立有限元模型,采用快速非线性分析方法分析对比摩擦摆、阻尼器、速度锁定器等减隔震方案在各种装置参数下的减震效率。研究表明:由于大跨铁路钢桁连续梁桥墩身自振导致的地震力较大,摩擦摆方案内力减震效率一般,同时墩底内力对滑动面半径变化并不敏感,在选取滑动半径时应更多地考虑行车平顺性和梁端位移值的限制。速度锁定器会极大地增加此类桥梁地震输入能量,不适用于此类桥型。阻尼器方案对活动墩内力减震效果明显,但不能有效降低固定墩内力。摩擦摆支座附加阻尼器组合减震方案能有效控制此类桥梁的内力和位移响应。研究结论可为大跨度钢桁连续梁桥减隔震设计提供参考。
To investigate appropriate seismic mitigation and isolation schemes and rational optimal parameters for long-span railway steel truss continuous beam bridges, based on a three-span railway steel truss continuous beam bridge with a total length of 504 m, a finite element model was built with the non-linear finite element analysis program SAP2000. The damping efficiencies of different seismic mitigation and isolation devices, such as the friction pendulum, lock-up device, and damper, were compared by the fast non-linear analysis method. The results showed that, since the natural vibration of bridge piers may cause significant earthquake force, the scheme with a friction pendulum system does not show high efficiency. The lock-up device will greatly increase the seismic input energy of this kind of bridge, therefore, it is not recommended in this case; the scheme with a damper can significantly reduce the seismic response of piers with movable bearings; however, it cannot effectively reduce the seismic response of piers with a fixed bearing. A combination of the friction pendulum bearing and damper can effectively control the internal forces and the displacement response of this type of bridge. The conclusions can provide valuable reference for the seismic isolation of long-span railway steel truss continuous beam bridges.
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