Early Age Sealing Capacity of Structural Mortar with Integral Crystalline Waterproofing Admixture

Abstract

Crystalline admixtures embedded in concrete may react in the presence of water and generate thin crystals able to fill pores, capillaries and micro-cracks. Once the concrete has dried, the crystalline chemicals sit dormant until another dose of water starts the crystallization again. The research aims to analyses the early age self-sealing effect of a crystalline admixture at a dosage rate of 1–3% of the cement mass. Specimens made with two types of gravel were pre-loaded with three-point bending to up to 90% of the ultimate capacity, and conditioned through wet–dry cycles. Micro-crack closure was measured with a microscope after pre-loading, and after 1 day, 4 days, 8 days, 14 days and 20 days of wet–dry exposure. The results show that an admixture content of 3% achieves the best early self-sealing performance. These results are also confirmed by probabilistic analyses, which also emphasize the self-sealing potential of lower ICW contents.

Ameliorating the Mechanical Parameters, Thermal Stability, and Wettability of Acrylic Polymer by Cement Filling for High-Efficiency Waterproofing

“…A surface with a contact angle >90 °C is regarded as hydrophobic, whereas a surface with a contact angle <90 °C is considered hydrophilic [ 10 ]. In addition, waterproofing materials could be classified into flexible and stiff waterproof materials [ 11 ]. The flexible waterproof materials have the characteristics of flexibility and high durability, meanwhile, they are weak at adhesion.…”

Research on the production of cement composites with autonomous self-healing performance

“…The self-healing mechanism is produced because of chemical reactions of a self-healing agent embedded directly, embedded in capsules or introduced through vascular networks when designing and making the concrete mixture. Among the most used systems are superabsorbent polymers [9], [10], crystalline mixtures [11], [12], microencapsulated sodium silicate [13], tubes with adhesives [14][15][16] and bacteria [17][18][19][20].…”

“…The capacity of the self-healing mechanism can be improved by adding some mineralizing waterproofing additives (ICW)to the composition of the concrete that react in the presence of water and generate thin crystals capable of filling pores, capillaries, and micro-cracks [12], [24].…”

Research upon self-sealing of fibre reinforced mortar with integral crystalline waterproofing admixtures

“…Next, the paper provides experimental information about the self-sealing potential of mortars with ICW admixtures. An ICW content of 1-3 % of the mass of the Portland Cement was studied [9].…”