桥梁负弯矩区钢-混叠合连续梁力学性能研究

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中图分类号：U448.38 文献标志码：A 文章编号：1005-8249（2025）06-0123-05

DOI：10.19860/j.cnki.issn1005-8249.2025.06.021

Abstract：：Thisstudyaddresss theproblemof crack formationinthenegative momentregionsof steel-concretecomposite continuous beam bridges，usingtheShiqing Road Bridgeasacase study.Asegment modelof the negative moment zoe was establishedusing Finiteelement software，whereinultra-highperformanceconcrete（UHPC）partiallyreplacesordinary concrete （NC）to createa UHPC-NCcomposite steel beam.Acomparative analysis wasconducted toevaluatetheffectsof diferentconcrete typesonthetensilestresss experiencedattheuppersurfaceof thecompositestelbeamandinthecoection components.Through orthogonalanalysis，weasesed the influenceof UHPC strength，topslab thickness，and widthonthe maximumtensilestresss atboth theupper surface andconnectioncomponents.Theresultsshowthat the UHPC-NCcomposite top slab reduces the maximum tensile stress at the upper surface and in the connection components by 11.2% and 10.1% ， respectively，when compared tothetraditional stel-concrete topslab.The UHPC-NCcompositetopslab demonstrates superiorstiffness，with theinclusionof steelfibersenhancing itsoverallresistance todeformation.Theimpactonmaximum tensile stressat the upper surface is ranked as follows：UHPCconcrete strength，top slab thickness，and top slab width.In contrast，thetensilestressintheconnectioncomponentsisprimarilyinfluencedbyUHPCconcretestrengthandtopslab thickness. The optimized design leads to decreases of 4.1% and 3.0% in the maximum tensile stress at the upper surface and thetensilestressintheconnectioncomponents，respectively，relativetotheoriginaldesign．Theseresearch findingsprovide valuable theoretical support for the design and practical application of UHPC-NC composite steel beams.

Key words： UHPC-NC stacked steel beam； negative bending moment zone;orthogonal analysis

0 引言

钢-混组合梁具有自重轻、强度高、适用性强、跨越能力强和抗震性能好等优点，还可以降低截面高度，有良好的施工性，因而具有优越的经济技术优势[1]。（剩余5798字）