Deformation of Concrete Matrix Subject to Freeze-thaw Cycles

• 作 者: PengDu[1]YanYao[2]LingWang[2]DongyuXu[3]XinCheng[3]
• 机 构: Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University
• 出 处: The 14th International Congress on the Chemistry of Cement (
• 发表日期: 2015年期

　　Cyclic freeze-thaw has been recognized as one of the most primary factors leading to structure and function failure of concrete.Strain, which may have certain inherent advantages compared to traditional test parameters,such as real-time nondestructive monitoring, more accurate and continuous with little error that is caused by manual intervention and so on, was used to characterize the deformation and deterioration of concrete matrix under freeze-thaw cycles in this study.With the process of freeze-thaw cycles, the moving up strain hysteretic loop indicates that residual strain is produced in the concrete matrix.The produced residual strain proves that the damage of concrete matrix is a continued accumulated and irreversible deterioration process.This process is directly related to the continued initiation and propagation of cracks in matrix during freeze-thaw cycles.The variation of freeze characteristic temperature ATf and the variation of apparent frost heaving coefficient △αf defined in this study are able to characterize the freeze-thaw damage degree and frost resistance of concrete respectively.Besides, the residual strain produced in 3.5wt.% NaC1 solution is larger than in water, showing that the chloride attack accelerates the freeze-thaw damage of concrete.