摘要
为研究冻融循环与氯盐侵蚀作用下混凝土基体的变形和损伤,分别测量了快速冻融循环与氯盐侵蚀作用下混凝土基体的变形和干冻条件下基体的变形,研究了饱盐试件和干燥试件的变形与损伤演化行为。结果表明:饱盐混凝土在冻融循环与氯盐侵蚀作用下将产生不可逆的残余应变,基体的劣化是一个累积损伤的破坏过程,基体变形呈非线性且应变–温度曲线有回滞现象;残余应变来自于混凝土内部裂纹的萌生和扩展,它随着水灰比和冻融循环次数的增加而增大,可以用来作为饱盐基体损伤的量度;干燥试件在干冻条件下呈现线性收缩变形,基体的损伤程度很小,基体损伤度可利用应变–温度曲线得到的热膨胀系数进行描述。
The deformation and deterioration evolution of saturated concrete matrix and dried specimens subject to freeze-thaw cycles with chloride salt attack （FTCSA） and heating-cooling, respectively, were investigated via the measurement of the strain of concrete matrix using embedded strain gauges. The results show that the saturated concrete matrix under the action of FTCSA generates irre- versible residual strain, and the deterioration of concrete matrix is a clmmlative damage process. The saturated concrete exhibits a non-linear expansion deformation, and the strain-temperature hysteresis is also observed. The initiation and propagation of cracks in concrete matrix contribute to the residual strain, which increases with the increase of water to cement ratio and freeze-thaw cycle numbers. Therefore, the residual strain can be used as a measurement for concrete matrix deterioration. The dried concrete matrix shows a linear contraction deformation and slight damage. The degree ,of dried matrix deterioration can be characterized by thermal expansion coefficient calculated from a strain-temperature plot.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2012年第8期1133-1138,共6页
Journal of The Chinese Ceramic Society
基金
国家重点基础研究发展计划(2009CB623106)
关键词
冻融循环
变形
残余应变
饱水度
热膨胀系数
freeze-thaw cycles
deformation
residual strain
saturation degree
thermal expansion coefficient
