Ice Formation in Hardened Cement Paste—1. Mature Water-Saturated Pastes

2009 ◽  
pp. 425-425-14 ◽  
Author(s):  
C le Sage de Fontenay ◽  
EJ Sellevold
Keyword(s):  
Cement Paste ◽  
Ice Formation ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
Water Saturated

scholarly journals Salt frost attack on concrete: the combined effect of cryogenic suction and chloride binding on ice formation

2021 ◽  
Vol 54 (5) ◽  
Author(s):  
Matthias Müller ◽  
Horst-Michael Ludwig ◽  
Marianne Tange Hasholt
Keyword(s):  
Cement Paste ◽  
Damage Mechanism ◽  
Concrete Surface ◽  
Model Material ◽  
Ice Formation ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
Scanning Calorimetry ◽  
Freeze Thaw ◽  
Ice Content

AbstractScaling of concrete due to salt frost attack is an important durability issue in moderate and cold climates. The actual damage mechanism is still not completely understood. Two recent damage theories—the glue spall theory and the cryogenic suction theory—offer plausible, but conflicting explanations for the salt frost scaling mechanism. The present study deals with the cryogenic suction theory, which assumes that freezing concrete can take up unfrozen brine from a partly frozen deicing solution during salt frost attack. According to the model hypothesis, the resulting saturation of the concrete surface layer intensifies the ice formation in this layer and causes salt frost scaling. In this study an experimental technique was developed that makes it possible to quantify to which extent brine uptake can increase ice formation in hardened cement paste (used as a model material for concrete). The experiments were carried out with low temperature differential scanning calorimetry, where specimens were subjected to freeze–thaw cycles while being in contact with NaCl brine. Results showed that the ice content in the specimens increased with subsequent freeze–thaw cycles due to the brine uptake at temperatures below 0 °C. The ability of the hardened cement paste to bind chlorides from the absorbed brine at the same time affected the freezing/melting behavior of the pore solution and the magnitude of the ice content.

Study of the microstructure and Frost Behavior of HCP by Measuring the Dynamic Modulus of Elasticity

1986 ◽  
Vol 85 ◽  
Author(s):  
M. J. Setzer
Keyword(s):  
Pore Water ◽  
Cement Paste ◽  
Freezing Temperature ◽  
Frost Damage ◽  
Solid Particles ◽  
Ice Formation ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
Air Voids ◽  
Different Temperatures

ABSTRACTHardened cement paste can be regarded as a highly dispersed system of solid particles, air voids and water filled pores ranging in size from a submicroscopic to a macroscopic scale. Using a statistical model, the elastic moduli of solid particles, air voids and pore water can be combined appropriately to find a correlation between the modulus of hardened cement paste and the moduli, as well as respective volume fractions, of its constituents. Ice formation and the addition of aggregates in a mortar can easily be taken into account. On this basis the measurement of the dynamic elastic modulus of hardened cement paste and mortar at different temperatures and its evaluation provides much interesting data. The interaction of particles and pores is better understood. The ice formation can be studied. Since the freezing temperature of pore water is lowered in small gel pores, the pore size distribution can be calculated. Frost damage is observed directly. Therefore, this method is a valuable tool to improve the Munich model of hardened cement paste.

Sign in / Sign up

Export Citation Format

Share Document