Porosity and Water Absorption of Concrete with Multi-Crystalline Waterproofing Admixture: The Effect of Admixture Dosage and Ratio of Water to Cementitious Materials

Abstract

Concrete durability issues are associated with water penetration and concrete porosity. This submission investigates the performance of liquid multi crystalline waterproofing admixture (MCE) manufactured by International Chem-Crete Corporation (Dallas, TX, USA). The investigation included the two dosages of 1% and 2% MCE by the weight of cementitious materials. The standard testing methods described in ASTM C642 was used to measure density, water absorption and volume fraction of permeable pores for reference and MCE-dosed concrete specimens. This was done using the mix design of Iowa Department of Transportation (Iowa DOT) with various ratios of water to cementitious materials (w/cm) ranging from 0.37 to 0.54. The results are presented as curves of water absorption, fraction of permeable pores and density for reference and 1% and 2% dosed concrete as functions of w/cm ratio.  The findings demonstrate the efficiency of each of the investigated dosages of MCE in pore blocking waterproofing. MCE reduces the fraction of permeable pores and water absorption at the two dosages, with a slight densifying effect at 2% MCE. At high w/cm ratio, 2% MCE is recommended.

Keywords: concrete, moisture, pores, absorption, waterproofing, crystallization, durability, ASTM C642.