摘要
为研究青藏高原地区低温环境下钢管混凝土拱肋混凝土灌注后的水化放热规律,以川藏铁路拉林段藏木雅鲁藏布江特大桥为背景,采用恒温箱模拟低温环境,分别对Ф1.6 m、Ф1.4 m管径的钢管混凝土构件进行长期连续温度场监测试验,对低温条件下核心混凝土水化放热规律、水化放热模型、混凝土水化温度预测公式及变参条件下极值温差变化规律进行研究。结果表明:核心混凝土水化放热呈现出显著的大体积混凝土水化放热规律,复合指数式水化放热模型能够较好地反映低温灌注条件下管内混凝土温变状况,指数式计算模型可以较好地预测低温条件下管内混凝土温度变化情况,极值温差随参数变化呈现出较好的函数变化规律。
In order to study the law of hydration and heat release of concrete-filled arch ribs under low temperature in Qinghai-Tibet Plateau,with constant temperature box simulation in low temperature environment,long-term continuous temperature field monitoring tests of 1.6 m and 1.4m diameter of steel pipe concrete components are conducted respectively with reference to Yarlung Zangbo River Extra-large Bridge on Sichuan-Tibet Railway.The core concrete hydration exothermic regularity under low temperature conditions,hydration heat release model,concrete hydration temperature prediction formula and extreme temperature difference under the condition of variable parameter changes are studied.The results show that the core concrete hydration heat tends to have significant mass concrete hydration exothermic regularity and the complex exponential hydration heat release model can better reflect the status of concrete temperature change under the condition of low temperature perfusion tube,and the exponential calculation model can better predict the changes of the concrete inside the tube at low temperature,and the extreme temperature varies with parameters present an ideal law of function variation.
作者
周大为
邓年春
石拓
ZHOU Dawei;DENG Nianchun;SHI Tuo(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Guangxi Key Laboratory of Disaster Prevention and Structural Safety,Nanning 530004,China)
出处
《铁道标准设计》
北大核心
2020年第12期52-58,共7页
Railway Standard Design
基金
国家自然科学基金项目(51868006)
中国铁路总公司科技研究开发计划课题(2017G006B)
广西自然科学基金项目(2018 GXNSFAA138067)
广西高等学校创新团队及卓越学者计划项目(桂教人[2018]35号)。
关键词
铁路桥
钢管混凝土拱桥
水化热
指数式计算模型
入仓温度
环境温度
railway bridge
concrete filled steel tubular arch bridge
hydration heat
exponential model
warehousing temperature
environment temperature
