Title of article :
Freeze–thaw behavior of air entrained cement paste saturated with 10 wt.% NaCl solution
Author/Authors :
Zeng، نويسنده , , Qiang and Li، نويسنده , , Le and Pang، نويسنده , , Xiaoyun and Gui، نويسنده , , Qiang and Li، نويسنده , , Kefei، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2014
Abstract :
By experimental measurement and poroelastic approach, the present study attempts to assess the freeze–thaw (F–T) behavior of air entrained cement pastes saturated with 10 wt.% NaCl solution. The strains of cylindrical cement pastes were measured under undrained cyclic F–T loading. Six distinct stags of the strains for one whole F–T cycle were identified. Meanwhile the specific strains of thermal contraction, hydraulic expansion, ice nucleation expansion and residual expansion were analyzed. A poroelastic model involving thermodynamic equilibrium between ice crystal and pore solution, pore size distribution and constitutive poromechanical equations was developed to quantify the strain sources. The obtained results indicated: 1, air-void entrainment tends to decrease the thermal contraction but to increase the hydraulic expansion, ice nucleation expansion and residual expansion; 2, the established poroelastic approach can capture the experimental data; 3, changes of salt concentration, water activity and fusion energy play minor roles on the strains of the porous material, while density changes as water crystallizes and the thermal contractions remain the dominative factors.
Keywords :
strain , freeze-thaw , cement paste , NaCl solution , Poroelastic model , Air void
Journal title :
Cold Regions Science and Technology
Journal title :
Cold Regions Science and Technology