2023.3,3（2）|专题:钢桥设计制造新技术超静定钢桁架桥预拱度设计的温度假载优化法李毓龙，何任远，刘厚军（中铁大桥勘测设计院集团有限公司，湖北武汉430056）摘要：为使超静定钢桁架桥在成桥后达到目标线形，需要确定桁架杆件在制造阶段的无应力长度。对于超静定钢桁架桥，若采用常规温度法确定杆件的无应力长度时，可能会使拼装后的结构产生较大的杆件次内力。为此，提出了温度假载杆件的选取原则，在此基础上建立了基于拼装次内力最小化的温度假载优化法，通过假载杆件的温度荷载和桥面节点位移及冗余支座反力的关系，求解一组既满足预拱度，冗余支座次内力又较小的杆件假载温度组合。以南通市深南路大桥三跨连续钢桁梁为例验证该方法的适用性，计算发现该方法可在满足设计预拱度逼近目标预拱度的基础上，控制杆件拼装次内力满足了安装要求。该方法可为超静定钢桁架桥的预拱度设计提供参考。关键词：桁架桥；超静定钢桁架；预拱度；温度假载优化法；拼装次内力Temperaturepseudo-loadoptimizationmethodforpre-camberdesignofstaticallyindeterminatesteeltrussbridgesLIYulong,HERenyuan,LIUHoujun（ChinaRailwayMajorBridgeReconnaissanceandDesignInstituteCo.Ltd.，Wuhan430056，China）Abstract：Inordertomakethesteeltrussbridgereachthetargetalignmentaftercompletion，itisnec⁃essarytoobtaintheunstressedlengthoftrussmembersinthemanufacturingstage.Forstaticallyinde⁃terminatesteeltrussbridge，iftheunstressedlengthofthememberisdeterminedbytheconventionaltemperaturemethod，theassembledstructuremayproducelargesecondaryinternalforceinthemem⁃bers.Therefore，thispaperproposesaselectionprincipleoftemperaturepseudo-loadmembers.Onthisbasis，atemperaturepseudo-loadoptimizationmethodisestablishedviatheminimizationofthesecondaryinternalforceintheassemblyprocess.Throughtherelationshipbetweenthetemperatureloadofthefalse-loadedmemberandthedisplacementofthebridgedecknodeandthereactionforceoftheredundantabutment，agroupofmemberfalse-loadedtemperaturecombinationsaresolvedsuchthatthepre-camberissatisfiedandthesecondaryinternalforceoftheredundantabutmentisalsosmall.Finally，thethree-spancontinuoussteeltrussbridgeoftheShennanRoadBridgeinNantongCityistakenasanexampletov...
