摘要
为了揭示严寒地区冬季温度梯度对混凝土箱梁的影响,笔者对绥芬河斜拉桥箱梁的初期运营阶段进行了全天候的温度测试。从理论和试验两个方面,验证并揭示温度是如何传递并影响箱形梁的,进而明确热传导、热对流、热辐射分别对箱梁的影响程度。为严寒地区混凝土斜拉桥设计时温度荷载的确定提供参考,也为以后箱梁温度梯度监测时间的确定建立科学依据。试验发现负温度梯度明显存在、实测温度梯度较小,满足中美两国规范的要求、冬季的温度梯度值远远小于夏季。建议今后对严寒地区斜拉桥的设计,主要应考虑辐射热大的夏天温度应力对箱梁混凝土的影响。
To find out the effect of temperature gradient in frost region in Winter on the concrete box girder, a whole day＇s temperature of box girder of Suifen River cable-stayed bridge in its initial operation stage was measured. From theory and experiment, it was verified and disclosed how temperature transferred and affected box girder, and to what degree heat conduction, heat convection and heat radiation had effect on box girder respectively, which provided scientific reference and basis for the determination of temperature load during the design of cable-stayed bridge in frost region and for the decision of monitoring time of box girder＇s temperature gradient. After experiment, there evidently existed a negative temperature gradient and the temperature gradient obtained by measurement was low, which meets the requirements of Chinese and American norms; at the same time, the value of temperature gradient in winter was extremely lower than that in summer. It is suggested that the effect of temperature stress with a high radiant heat in summer on concrete box girder should be mainly taken into account during the design of cable-stayed bridge in frost region.
出处
《中国安全科学学报》
CAS
CSCD
2007年第4期146-150,共5页
China Safety Science Journal
基金
国家自然科学基金资助(50308008)
关键词
斜拉桥
冬季
夏季
负温度梯度
混凝土箱梁
cable-stayed bridge
winter
summer
negative temperature gradient
concrete box girder
