考虑不同应力水平影响的混凝土徐变预测模型修正

摘要

In order to carry out the research on the modification of concrete creep prediction model,the creep test and numerical simulation of concrete under different stress levels were carried out.Through numerical simulation,the creep characteristics of concrete under tensile and compressive stress,cyclic stress and biaxial stress were studied.For the low accuracy of the creep prediction model CEB/FIP 1990,the useful creep coefficient correction value was given based on creep characteristics of concrete under different stress levels.The results show that the numerical simulation method in this paper provides a new idea for the modification of concrete creep prediction model.%为开展混凝土徐变预测模型修正研究,对不同应力水平下的混凝土进行了徐变试验和数值模拟,并进行了相互印证.通过数值模拟,研究了拉压应力、周期应力、双轴应力下的徐变特性,针对徐变预测模型CEB/FIP 1990估算精度低的现状,基于不同应力水平下混凝土徐变特性,结合工程实际给出了便于运用的徐变系数修正值.研究结果表明,采用的数值模拟方法为混凝土徐变预测模型的修正提供了一条新思路.