| Title |
Carbonation Reaction and Strength Development of Air Lime Mortar with Superplasticizer |
| Authors |
Kang, Sung-Hoon ; Hwang, Jong-Kook ; Kwon, Yang-Hee |
| DOI |
https://doi.org/10.5659/JAIK_SC.2019.35.7.179 |
| Keywords |
Air lime; Carbonation reaction; Strength development; Carbon dioxide; Calcium hydroxide; Calcium carbonate |
| Abstract |
Air lime is a traditional building material of Korea. It had been used in roofs, walls, floors and masonry joints of traditional buildings until
the advent of Portland cement. However, due to its low strength and durability, the lime is currently avoided as a repair or restoration
material for the preservation of architectural heritage. Furthermore, due to the current practice of using hydraulic materials such as Portland
cement, understanding of the material characteristics of air lime is very poor in practice. In this context, this study intended to improve the
mechanical properties of the air lime mortar by reducing water contents, and also the carbonation reaction of the mortar was quantitatively
evaluated to clearly understand the characteristics of this material. Accordingly, air lime mortar with a water-to-binder ratio of 0.4 was
manufactured using polycarboxylate-type superplasticizer. During the 7 days of sealed curing period, the mortar did not harden at all. In other
words, there was no reaction required for hardening since it could not absorb carbon dioxide from the atmosphere. However, once exposed to
the air, the compressive strength of the mortar began to rapidly increase due to the carbonation reaction, and the strength increased steadily
until the 28th day; after then, the strength development was significantly slowed down. On the 28th day, the mortar exhibit a compressive
strength of about 5 MPa, which is equivalent to the European standard regarding strength of hydraulic lime used for preservation of
architectural heritage. |