ABSTRACT
Abstract The intention of the investigations was to find out the resistance of different types and qualities of cements in standard mortars against freeze thaw cycles (FTC) in water and in Nad-, CaCl2' and urea-containing solutions. With respect to the thaw media water the results show expansion together with cracking and decrease of strength nearly without exception. The largest average number of FTC were reached in water. In this case it could be assumed that the mortar specimens freeze from outside to the center. Hydraulic pressure is the cause of the destruction of the entire structure. The NaCl-solution causes mainly loss of weight with scaling of the surface and with the lowest average number of FTC. Chloride and enrichments of chloride could only be analysed in the surface regions of the specimens. In contrast to those in CaCl2' solution losses of weight as well as expansion could be measured. The damages started after more cycles. Chloride and chloride enrichments could be measured in the surface region and in the center of the specimens which had been treated for a longer period. The thaw medium urea takes a middle position regarding the type and intensity of the damage. It can be assumed that the specimens freeze in solutions with deicing additions preferably from the center to the surface causing their scaling and less expansion accompanied by strenght decrease. The degree of the damages due to the deicing media increases in the following row:
Water < CaCl2 < Urea < NaCl
cements PZ55 PZ55-NA(HS) PZ45F PZ 45 L - NA (HS) PZ35F PZ 45 F - HS EPZ 35 F HOZ35L FPZ 45 L PKZ35F TrZ 35 L POZ 35 F/E
admixtures [wt.-%] -
27/25 50/46 20/26 17/18 25 n.b.
