THE EFFICIENCY OF AUTONOMOUS CRACK HEALING OF MORTAR IN CHLORIDE SOLUTIONS

Author(s): Maes, M. and De Belie, N.
Paper category: Conference
Book title: XIII International Conference on Durability of Building Materials and Components - XIII DBMC
Editor(s): Marco Quattrone, Vanderley M. John
Print ISBN: none
e-ISBN: 978-2-35158-149-0
Publication year: 2015
Pages: 198-205
Total Pages: 8
Language: English

Abstract: A lot of damage is reported for constructions in marine environments. Marine environments are very aggressive, since sea water consists mainly of chlorides. When cracks appear in the concrete structures, chlorides will penetrate faster and initiate corrosion and deterioration faster as well. A possible solution is autonomous crack healing by means of encapsulated polyurethane (PU).

Chloride resistance of autonomously PU-healed mortar was tested and compared to cracked and uncracked mortar. To do so, realistic crack widths of 100 and 300 μm were formed by means of a controlled splitting test. To obtain autonomous crack healing, glass tubes filled with a prepolymer on the one hand and an accelerator on the other hand were placed in the specimens at middle height. Upon crack formation, the tubes break and the healing agent is released. Then, the specimens were immersed for 7 weeks in a 165 g/l NaCl solution. After the immersion period, colour change boundaries as well as chloride profiles at different distances from the (healed) crack were obtained.

Based on the results, it seems that autonomous crack healing by means of PU has a beneficial influence on chloride resistance. Nevertheless, there is room for further improvement.

Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00