考虑温度变化的钢管混凝土徐变试验研究及预测模型  

Prediction Model for Creep of Concrete Filled Steel Tube(CFST)Based onTemperature Variation by Experimental Study

作　　者：张戎令[1] 郝兆峰 祁强[1] 王起才[1] 马丽娜[1] 黄国栋 ZHANG Rongling;HAO Zhaofeng;QI Qiang;WANG Qicai;MA Lina;HUANG Guodong(National and Provincial Joint Engineering Laboratory of Road&Bridge Disaster Prevention and Control,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学道桥工程灾害防治技术国家地方联合工程实验室,兰州730070

出　　处：《材料导报》2021年第20期20028-20034,共7页Materials Reports

基　　金：国家自然科学基金(51768033,52068042);甘肃省杰出青年基金(21JR7RA344);兰州市科技计划项目资助(2018-4-33)。

摘　　要：为了定量得出实际温度变化对钢管混凝土徐变的影响规律,考虑ACI209徐变模型的计算形式,基于龄期调整的有效模量法,并通过Arrhenius理论引入温度参数,推导得出了考虑温度变化的钢管混凝土热徐变计算公式。并在室内进行了20℃恒定温度、季节变温下的钢管混凝土徐变试验。试验结果得出,相对于20℃恒温条件下的徐变,温度从20℃升高到40℃时,徐变应变增长幅度达57.8%;温度从40℃升温到60℃时,徐变应变增幅达34.1%。变温对钢管混凝土影响较大,处于实际变温环境下的钢管混凝土结构进行徐变设计时,应考虑变温对钢管混凝土徐变的影响。通过试验数据和理论计算值对比得出,理论计算值与试验结果吻合较好,验证了考虑温度影响的徐变预测模型的准确性,可为受实际温度影响的钢管混凝土徐变设计提供参考。In order to quantitatively calculate the influence of actual temperature change on the creep of CFST,creep models of the ACI209 are consi-dered,and the temperature parameters are introduced by Arrhenius theory.The formula for calculating the thermal creep of CFST considering temperature changes is derived by the effective modulus method based on age adjustment.The creep test under constant temperature of 20℃and seasonal temperature change is carried out in the laboratory.The test results showed that compared with the creep under the constant temperature of 20℃,the growth rate of creep strain is 57.8%when the temperature is raised from 20℃to 40℃,and the growth rate of creep strain is 34.1%when the temperature is raised from 40℃to 60℃.The temperature change has a great influence on the creep of CFST.The temperature change should be considered when the CFST structure is designed under the actual temperature change environment.The model predictions are in good agreement with the test data by the comparison of the experimental data and the theoretical calculation value.It is indicating that the accuracy of the theoretical prediction of temperature is considered,which can provide reference for the creep design of CFST affected by the actual temperature.

关 键 词：钢管混凝土 时变温度 徐变 预测模型 试验验证 

分 类 号：TU398[建筑科学—结构工程]