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斜拉式混凝土连续桁梁预应力施工  [PDF]
张林光
铁道工程学报 , 1997,
Abstract: ?本文介绍了卫运河特大桥斜拉式混凝土连续桁梁预应力施工技术,对复杂预应力结构的孔道成孔方法、钢铰线张拉顺序的确定、张拉力控制方法、孔道压浆工艺进行了详细论述,提出了预应力施工中有关施工计算的方法,并对卫运河桥桁梁结构施工进行了简要介绍。
大跨单索面公轨两用钢桁梁斜拉桥施工风险分析  [PDF]
曾勇,郑慧君,向中富
重庆交通大学学报(自然科学版) , 2014, DOI: 10.3969/j.issn.1674-0696.2014.04.06
Abstract: :?在层次分析法的基础上提出了基于层次分析法-灰色系统理论-人工神经网络-有限元分析-蒙特卡罗理论的定性、定量风险分析方法,并将其应用于某大跨单索面公轨两用钢桁梁斜拉桥。研究结果表明:当结构位移状态仿真次数超过200万次时,钢桁梁最大悬臂端位移失效概率仅为3%,失效概率可控,该风险分析方法采用概率理论更加准确的确定了桥梁风险因素对桥梁结构的影响。
斜向断层效应初析  [PDF]
余国强
地质与勘探 , 1985,
Abstract: 在构造地质学教科书中,常以走向断层来研究断层效应.然而,走向断层只是断层中特殊的一类,在野外最常见的是斜向断层,因而研究斜向断层的断层效
公轨两用钢桁桥轨道横梁与整体节点连接头的疲劳荷载  [PDF]
任伟平, 李小珍, 李 俊, 强士中
中国公路学报 , 2007,
Abstract: ?为评定公轨两用钢桁桥下层轨道横梁与焊接整体节点连接头在交通荷载作用下的疲劳损伤累积,对该细节在桥梁设计寿命内车辆荷载所产生的疲劳荷载谱的计算方法进行了研究。在对桥梁的车辆荷载进行分析的基础上,参照各国相关规范,建立了代表桥梁设计寿命内真实运营状况的疲劳荷载模型,并通过全桥三维有限元分析模拟计算该连接细节所承受的荷载历程。依据疲劳损伤累积理论,确定了公轨两用钢桁桥轨道横梁与整体节点连接头验证性疲劳试验的试验荷载。结果表明:该连接细节的疲劳损伤荷载基本不受上层汽车的影响,主要取决于轻轨,可以通过直接将轻轨计算结果乘以一定的提高系数得出。
规则斜浪中船舶多自由度耦合的参强激励横摇  [PDF]
周光耀,唐友刚
哈尔滨工程大学学报 , 2018, DOI: 10.11990/jheu.201611079
Abstract: 为研究船舶的参强激励运动,本文建立了瞬时等效旋转矩阵的新坐标转换方法,描述船舶在空间中的多自由度运动。基于瞬时等效运动体系建立考虑随船坐标系位置瞬变的多自由度耦合运动方程。引入航向控制条件,对多自由度运动方程进行改进,从而研究船舶在规则斜浪中定向航行下的参强激励横摇运动。并以某C11集装箱船为例,计算其在规则斜浪中不同波浪条件下的运动。分析发现:小波向角差异下的运动存在一个相对固定的相位时间延迟;斜浪中参数激励和强激励对运动的影响与波向角、波幅和波长有关,且在参强激励发生时,其运动频率是否受到固有频率的影响也与这些波浪条件有关。
沪通公铁两用长江大桥新型全焊箱-桁组合节点受力性能研究
Research on mechanical behavior of new type box girder-truss composite welded integral joints of Hutong Yangtze river rail-cum-road bridge
 [PDF]

张晔芝,李权,张晓龙
ZHANG Yezhi
,LI Quan,ZHANG Xiaolong

- , 2016,
Abstract: 在建的沪通长江大桥是目前世界上跨度最大的公铁两用斜拉桥,通行4线铁路、6车道公路,孔跨布置为:(142+462+1 092+462+142)=2 300 m。下层铁路桥面系为2.2 m高的封闭式正交异性板钢箱梁,主桁节点欲采用新型全焊箱-桁组合节点,节点板将主桁相关杆件和铁路桥面系钢箱梁连成一个整体,节点外形简洁,但内部结构构造和受力状态都很复杂,各构件内部加劲肋众多,形式、尺寸多样。在全桥空间有限元分析的基础上,选取具有代表性的E60中桁节点和两个最不利的主力组合工况,完成了局部精细有限元分析和1:3的缩尺模型试验。结果表明,E60中桁节点各相关构件绝大部分区域的应力水平不高,Mises等效应力小于200 MPa,实测结果与有限元分析结果吻合较好。但在节点板与斜杆连接处的边缘、节点板与下弦杆顶板、横隔板等多板连接处的边角处有应力集中现象,有限元分析的局部最大Mises等效应力超过200 MPa,但都小于材料Q370qE的屈服应力。试验所得的离有限元计算最高应力点2~4 cm处的实测应力都远小于有限元计算的最大应力值,表明边角处的高应力范围很小,很局部。这种新型全焊箱-桁组合节点结构构造合理,受力性能良好,安全,可以在沪通公铁两用长江大桥上应用。
Hutong Yangtze river bridge under construction is a rail-cum-road cable-stayed bridge with the largest span in the world. Four line railways and six lanes are arranged on the bridge and the span of the bridge is 142+462+1092+462+142 = 2300m. 2.2m height closed steel orthotropic plate box girder is used as the railway floor system. A new type box girder-truss composite welded integral joint are tended to be adopted as the lower main truss joint. Using two connecting plates the relevant truss bars and steel orthotropic plate box girder of the railway floor system are welded as a whole. The appearance of the joint looks concise but the internal structure construction are very complex. Many stiffening ribs of various kinds and scale are arranged inside every components. Refined finite element analysis and 1:3 reduced scale model test were completed for the representative E60 middle truss 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 E60 middle truss joint are not high, and their Mises equivalent stress is less than 200 MPa. The test results are well coincided with that of the finite element analysis. But stress concentration exists at the joint plates edges connecting with the inclined web member and at the multi-plate connecting corners such as the joint plate connecting with the top plate of the lower chord and the diaphragm plates, where the maximum Mises equivalent stress is over 200MPa but less than the yield stress of Q370qE according to the refined finite element analysis. The tested stresses of the testing points which are away the finite element maximum stress point 2 to 4cm are far less than that of the finite element analysis, which shows that the high stress areas are very small and local, and the structure of the new type welded integral joints is reasonable, its behavior is good and safe, which indicates that this new type of box girder-truss composite welded
钢桁斜拉桥板桁温差效应分析  [PDF]
向中富,蒋彧
重庆交通大学学报(自然科学版) , 2012, DOI: 10.3969/j.issn.1674-0696.2012.supp.1.30
Abstract: :?以江津粉房湾大桥为依托工程,对钢桁斜拉桥所存在的板桁温差效应进行分析,在参考各国规范对温差效应规定的基础上,提出了钢桁斜拉桥板桁温差效应分析方法。通过比较不同温差作用下钢桁梁与桥面板连接部位的变形和受力情况,研究温差效应对结构的影响程度,并提出了有效解决温差效应的措施。
双塔钢桁斜拉桥斜拉索破坏动态响应
Dynamic response of cable breakage in double-tower cable-stayed bridge with steel truss girder
 [PDF]

郑小博,,,宋一凡
- , 2017,
Abstract: 针对斜拉索在使用过程中的失效可能导致斜拉桥承载力下降的问题,提出反向加载模拟斜拉索断裂的作用效应,通过不同的加载时间模拟拉索破坏的时间和对整体结构的激励,分析斜拉索在不同断裂时间下的斜拉桥动力响应特征;并根据美国PTI《斜拉桥设计指南》中对斜拉索断裂的相关规定,提出单根斜拉索断裂对负载斜拉桥影响的计算方法,即对结构自重和汽车活载的放大。研究结果表明:提出的方法较准确地模拟了斜拉索断裂及其对整体结构的冲击作用;整体结构的动力响应随击振时间Td的变化而改变,当Td大于整体结构的自振周期时,结构在击振期间会出现显著动力响应;当Td小于整体结构的自振周期时,结构的最大动力响应出现在击振完成后的自由振动期间;根据PTI中对斜拉索断裂造成的全桥荷载放大作用,也较为真实地分析了其作用最大值,斜拉桥在拉索破坏反向放大荷载、恒载及车道分布荷载组合作用下,主梁最大位移出现在中跨跨中附近,与相同汽车荷载分布下完好结构的最大竖向位移差值出现在中跨跨中附近;距离主塔及支座越远,所受影响越大;与完好结构索力最大差值出现在失效拉索的相邻索。提出的方法进一步验证了在PTI中根据拟静力法求得的单索破坏造成的最大动力放大系数2.0是合理的,但如果考虑2根以上斜拉索同时失效,则根据2.0的动力放大系数进行安全储备设计是不足的。
For the problem that failure of cables in the process of using may lead to a serious decline in bearing capacity of cable-stayed bridges, this paper proposed a reverse loading method to simulate the effect of cable breakage. Through simulating the time of cable damage and incentive to the whole bridge with different loading time, the dynamic response characteristics of cable-stayed bridges caused by different breakage time were analyzed. According to the relevant regulations on cable breakage in recommendations of stay cable design, testing and installation of PTI (Post Tensioning Institute) in American, a calculation method of the effect of single cable breakage on the loaded cable-stayed bridge was put forward, that is, the amplification of structural weight and the live load of automobile. The results show that the method of reverse loading is more accurate to simulate the breakage of cables and the impact to the whole structure. The dynamic response of the whole structure varies with the change of shock time Td. When Td is larger than the natural vibration period of the whole stricture, the most obvious dynamic response of the structure will occur during the shock period, when Td is smaller than the natural vibration period of the whole stricture, the most obvious dynamic response of the structure will occur during the free vibration after the shock. On the other hand, the maximum value of the action is also analyzed more realistically according to the amplification of the full-bridge load caused by the cable breakage in PTI recommendation. Under the load combination of reverse amplification load, dead load and the driveway distribution in cable failure of cable-stayed bridge, the maximum displacement of main girder appears in the area of the span center of mid-span. Under the same vehicle load distribution, the maximum difference of vertical displacement appears near the span center of mid-span, compared to the intact structure. The farther the distance from tower and supporter, the greater the
武汉天兴洲公铁两用长江大桥关键技术研究  [PDF]
秦顺全
工程力学 , 2008,
Abstract: 天兴洲公铁两用长江大桥是北京至广州客运专线在武汉跨越长江的重要桥梁,其主桥为主跨504m的双塔三索面三主桁斜拉桥,铁路、公路分上下两层布置。重点介绍武汉天兴洲公铁两用长江大桥结构体系、主桁结构、基础选型和施工等关键技术及研究成果。
钢桁梁悬索桥柔性中央扣梁端锚固方式比较研究  [PDF]
曹永睿,韩立中,姜锡东,张劲泉
公路交通科技 , 2013,
Abstract: 通过比较某在建的大跨径钢桁梁悬索桥上2种柔性中央扣斜拉索梁端锚固方式,研究了锚箱式和耳板式柔性中央扣锚固系统的构造和设置方法,并运用大型有限元分析软件ANSYS进行了空间有限元分析,分析了锚固系统的传力途径及各板件的应力分布情况,分析结果表明柔性中央扣斜拉索耳板式锚固系统应力集中点较少且应力极值较小,相比锚箱式系统更适合在索力不太大又受结构安装空间限制的钢桁梁悬索桥上使用。该结论可为今后在同类大跨径钢桁梁悬索桥上选择合适的柔性中央扣斜拉索梁端锚固系统提供有意义的参考。
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