基于收缩徐变短期试验结果的高性能粉煤灰混凝土桥梁长期效应预测  

Prediction of Long-term Effect on High Performance Fly Ash Concrete Bridge Based on Short-term Test Result of Shrinkage and Creep

作　　者：罗许国[1,2] 戴公连[2] 

机构地区：[1]湖南科技大学土木工程学院,湖南湘潭411201 [2]中南大学土木建筑学院,湖南长沙410075

出　　处：《中国公路学报》2009年第3期64-69,共6页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(40671153)

摘　　要：以8根不同掺量的高性能粉煤灰混凝土无黏结预应力梁的收缩徐变试验为基础,提出了从混凝土模型梁短期试验值推算相应混凝土梁在该桥梁工作环境下收缩应变及徐变系数的方法,进而得出桥梁的徐变长期效应计算式;结合桥梁规范JTG D62—2004中收缩模型与徐变模型的思想,得出计算混凝土桥梁收缩应变及徐变系数的修正公式。该公式预测值与试验结果的比较表明:预测值具有较好的精度,且该预测方法不需做材料的收缩徐变试验,亦避免了从标准环境下用试验值推算桥梁工作环境下收缩徐变可能产生的误差。Based on the experimental results of shrinkage and creep of eight non-glued concrete beams with different mixtures of high performance fly ash, a strain and creep coefficient from short-term test of concrete bri bridge was forward. Then, the calculation equation of shrinkage on the model and creep bridg model method of deducing the shrinkage dge the under working condition of the long-term effect of creep and e was got. Combined with the concept of JTG D62--2004 for the shrinkage , a modified formula was obtained for computing shrinkage coefficient of concrete bridge. The comparisons between the theoretical analysis show that the predicted value holds a good accuracy. When the method is used, strain and creep and test results there is no need to implement material test of shrinkage and creep, thus it can avoid the errors that might be resulted from deducing the real shrinkage and creep of concrete under the bridge working environment through the test results obtained under standard condition.

关 键 词：桥梁工程 高性能粉煤灰混凝土 收缩徐变试验 长期效应 模型梁 

分 类 号：U448.33[建筑科学—桥梁与隧道工程]