Pan Zuanfeng, Zhang Haipeng, Zeng Bin, Wang Yuwei
College of Civil Engineering, Tongji University, Shanghai 200092, China.
Central Research Institute of Building and Construction of MCC Group, Beijing 100088, China.
Materials (Basel). 2023 Feb 13;16(4):1576. doi: 10.3390/ma16041576.
An extensive experimental database consisting of 2838 shrinkage data points and 3598 creep data points is used to evaluate the accuracy of the newly proposed CEB-FIP 2010 model in predicting the creep and shrinkage of concrete structures. To study the applicability of the model for high-strength concrete in general environments, the database was developed by only retaining the test data of concrete components with the average compressive strength greater than 30 MPa and the relative humidity in the test environment less than 95%. On this basis, combined with the B3 and CEB variation coefficient methods, the paper mainly adopts the residual method to assess the accuracy of the CEB-FIP 2010 model and compare it with the previous model, CEB-FIP 1990. The influences of several properties, such as the compressive strength, the age of concrete, the relative humidity, and the component size on the prediction accuracy of these two models are further studied. The results show that for the CEB-FIP 2010 model within the time interval of 0-9000 days, 52% and 48% of the shrinkage strain residuals of the total specimens are located in the negative and positive regions, respectively, while the positive and negative regions of the CEB-FIP 1990 model account for 73% and 27%, demonstrating the CEB-FIP 2010 model has better performance in predicting shrinkage strain than the CEB-FIP 1990 model, whereas the two models have comparable accuracy in predicting creep compliance. The CEB-FIP 2010 model is more reliable for considering the effects of compressive strength, relative humidity, and age at loading on shrinkage and creep than for considering the effect of member size.
一个由2838个收缩数据点和3598个徐变数据点组成的广泛实验数据库被用于评估新提出的CEB - FIP 2010模型在预测混凝土结构徐变和收缩方面的准确性。为了研究该模型在一般环境下对高强度混凝土的适用性，通过仅保留平均抗压强度大于30MPa且试验环境相对湿度小于95%的混凝土构件的试验数据来建立该数据库。在此基础上，结合B3和CEB变异系数方法，本文主要采用残差法评估CEB - FIP 2010模型的准确性，并将其与先前的CEB - FIP 1990模型进行比较。进一步研究了抗压强度、混凝土龄期、相对湿度和构件尺寸等几个特性对这两个模型预测准确性的影响。结果表明，对于CEB - FIP 2010模型，在0 - 9000天的时间间隔内，总试件收缩应变残差的52%和48%分别位于负区和正区，而CEB - FIP 1990模型的正区和负区分别占73%和27%，这表明CEB - FIP 2010模型在预测收缩应变方面比CEB - FIP 1990模型具有更好的性能，而在预测徐变柔度方面两个模型具有相当的准确性。考虑抗压强度、相对湿度和加载龄期对收缩和徐变的影响时，CEB - FIP 2010模型比考虑构件尺寸的影响更可靠。
