雄商高铁黄河特大桥设计时速 350 km,铺设无砟轨道.根据防洪及通航要求,该桥主桥中部跨度布置为(4×260+280)m,属于超长联大跨桥梁.结合桥址处建设条件、长联无砟轨道高速铁路桥梁建设及高速铁路行车要求,从桥型的边中跨比、梁高、结构体系、轨面平顺性能等方面,分别确定拱加劲连续钢桁梁桥、斜拉桥、部分斜拉桥、连续梁拱桥 4 种桥型的最佳方案,并对各桥型最佳方案进行技术经济综合比选.比选结果表明:斜拉桥方案在多跨情况下刚度小,采用多种工程措施提升刚度后造价最高;部分斜拉桥方案边塔尺寸较大,混凝土梁应力较高且工期较长,造价较低;连续梁拱桥方案采用钢-混混合梁减轻自重,合理跨度得到提升,造价高;拱加劲连续钢桁梁桥方案技术经济性好、受力性能较好、施工速度快,且与环境契合,因此最终采用该桥型方案.

为了提高三相配电线路故障诊断的精准度和故障诊断效率,设计了一种新的三相配电线路故障诊断系统.根据三相配电线路故障的奇异性、不确定性、串联性以及能量特征,完成电路故障的多特征融合,提高配电线路故障诊断的响应速度.硬件区域重点对处理器、电路控制器以及电子互感器的功能和结构进行设计.在系统软件区域采用多特征融合方式,将三相配电线路的基本故障特征进行融合,完成三相配电线路故障特征的提取和诊断.实验结果表明,基于多特征融合的三相配电线路故障诊断系统能够有效提高诊断精度,提升诊断效率.

既有铁路换梁改造中,为了在尽量不减小铁路桥下净空的情况下,保证新建桥梁的强度和稳定性、减少施工对桥下公路运营及铁路本身运营的影响,文章开展了采用正交异性桥面板钢箱梁替代既有钢板梁结构应用的研究.由于正交异性桥面板钢箱梁自重轻、结构高度低等特点,施工方案可采用厂内预制现场拼装架设的方式,加快了工程进度,有效解决了既有铁路换梁存在的难题,可为类似工程提供参考.

Tied-arch continuous-beam bridge is a kind of bridge structure with novel shape and complex stresses.So the stability issues should not be neglected.Spatial analysis model of an actual bridge was established by ANSYS finite element software and the first stability of this bridge under the actions of various kinds of load combinations were analyzed in this article.The secondary stability of this bridge under the actions of geometric nonlinearity,material nonlinearity and dual nonlinearities were also analyzed respectively in this article.The comparing result verifies that the material nonlinear effect on the stability of this bridge is very big.Also general computing methods of arch bridge stability were introduced in this article.The results can provide reference for similar kinds of bridges.