变温度环境下混凝土的三维收缩徐变效应

3D Shrinkage and Creep Effects of Concrete Under Varying Temperature Environment

为准确分析混凝土的收缩徐变效应,基于收缩徐变的三维特性,对自然变温度环境下的混凝土收缩徐变效应进行了分析,建立了变温环境下混凝土三维收缩徐变效应的力学模型,并结合有限元分析软件ABAQUS开发了相应的计算程序,随后通过两个算例验证了方法的可行性与结果的可靠性.研究结果表明:对于长期下挠和混凝土应变,模型计算值最大误差分别为8.2%和–7.1%;模型能够很好地体现温度对徐变应变的影响,总体变化趋势与实测值较为一致,最大误差为–20.5%,随着龄期增长误差越来越小,最终值误差为6.4%.

In order to analyze shrinkage and creep effects of concrete exactly,based on the three-dimensional(3D)characteristics of shrinkage and creep,the shrinkage and creep effects of concrete under an ambient temperature environment were analyzed.A 3D shrinkage and creep effects mechanical model for concrete was established for varying temperature environments,and the corresponding calculation process was integrated with finite element analysis software ABAQUS.Then,the feasibility of the method and reliability of the results were verified using two examples.The results demonstrate that the maximum error of the model calculation is 8.2%and–7.1%for long-term deflection and concrete strain,respectively.The model suitably reflects the effect of temperature on creep strain,and the overall trend is consistent with the measured values.The maximum error is–20.5%,and this value decreases with the increase in age,the final error is 6.4%.