季德钧+刘江+张瑑芳+刘永健

摘要：对比了当前各国规范对钢混凝土组合梁竖向温度梯度形式及温度基数取值的相关规定，其中英国规范和欧洲规范最为详尽合理。在英国规范的基础上，通过桥位处太阳辐射强度的计算结果对温度基数的取值进行修正。以青海黄南地区哇加滩黄河特大桥为背景，建立全桥有限元杆系模型，对比分析了修正的英国规范温度梯度模式和中国规范的温度梯度模式作用下主梁的应力分布，以及斜拉桥在整体温差、索梁（塔）温差、主梁竖向温度梯度和主塔顺桥向温差作用下的温度效应及各构件的温度敏感性。结果表明：在青海高原高寒地区，进行桥梁设计时采用考虑地理位置修正的英国规范主梁竖向温度梯度模式进行计算并指导设计更偏于安全；对于主桥的某些构件，温度作用已经成为仅次于恒载的第二大控制作用，所得出的全桥各构件温度敏感性分析结果可为高原高寒地区同类桥梁的设计、计算提供参考和依据。

关键词：钢混凝土组合梁斜拉桥；高原高寒地区；温度效应；竖向温度梯度；敏感性

中图分类号：U442.5文献标志码：A

Temperature Effect Analysis of Steelconcrete Composite Girder

Cablestayed Bridge in Arcticalpine RegionJI Dejun1， LIU Jiang2， ZHANG Zhuanfang2， LIU Yongjian2

（1. Qinghai Provincial Authority of Highgrade Highway Construction Management， Xining 810008，

Qinghai， China； 2. School of Highway， Changan University， Xian 710064， Shaanxi， China）Abstract： Authors compared vertical temperature gradient and its basis in composite girder of current codes of different countries， in which British standard and Eurocode were the most detailed. Based on British standard， temperature basis was revised by calculating the solar radiation of bridge position. With engineering background of Wajiatan Yellow River Bridge in Huangnan， Qinghai， the finite element model of a whole bridge was established to calculate the stress of the girder at vertical temperature gradient of revised British code and Chinese code. Meanwhile， the temperature effects and sensitivity of each structural member under different temperature loads of entire temperature difference， cablegirder （pylon） temperature difference， vertical temperature gradient of girder and alongspan temperature gradient of pylon were analyzed. The results show that in Qinghai arcticalpine region， design of composite girder cablestayed bridge with vertical temperature curve of Chinese code is insecure； for some structural members， temperature effect plays the most important role except the dead load. The obtained sensitivity analysis results of different structural members in a whole bridge can provide references for the design and calculation of similar bridges.

Key words： concretesteel composite cablestayed bridge； arcticalpine region； temperature effect； vertical temperature gradient； sensitivity

0引言

桥梁结构是暴露于自然环境中的结构物，在日照、气温和寒潮等气象因素的作用下，结构会产生非线性的温度分布[12]，这种非线性温差会在结构中产生较大的温度应力和变形，往往会超过荷载所产生的效应，从而造成结构的破坏。如加拿大西部曾发生某钢混凝土组合梁桥垮塌事故，温度应力和变形是导致桥梁垮塌的主要原因之一[3]。……