EXPERIMENTAL STUDY OF EVOLUTION MODEL OF HIGH STRENGTH CONCRETE IN FREEZE-THAW CYCLES BASED ON CONTINUUM DAMAGE MECHANICS

In cold area frost damage is one of the major problems requiring high expenditures for the repair and replacement of concrete structures. Cracks and spalling of concrete take place because of repeated freeze-thaw cycles. It causes degradation of concrete with the initiation, propagation and connection of cracks. In this process concrete and degradation process of concrete can be seen homogeneous, so we can use continuum damage mechanics theory to study the degradation process. Freeze-thaw damage is seen as a low cycle fatigue failure and evolution model of concrete damage in freeze-thaw cycles can be established based on continuum damage mechanics. In the paper we study the freeze-thaw damage of high strength concrete which is mixed with super setting retarder and nano silica fume in accelerated freeze-thaw test, and establish the evolution model based on continuum damage mechanics.