| Title |
Development of hydraulic binder for repair/restoration of architectural heritage using Korean traditional pozzolan (Wasul) and natural hydraulic lime |
| Authors |
이다희(Lee, Da-Hee) ; 강성훈(Kang, Sung-Hoon) ; 권양희(Kwon, Yang-Hee) |
| DOI |
https://doi.org/10.5659/JAIK.2025.41.8.377 |
| Keywords |
Natural Hydraulic Lime (NHL); Brick Powder; Firing Temperature; Particle Size; Hydration Reaction; Pozzolanic Reaction; Architectural Heritage |
| Abstract |
This study aims to develop a hydraulic binder for the repair of Korean architectural heritage by utilizing Wasul, a traditional binder used
during the Joseon Dynasty. To achieve this, half of the natural hydraulic lime (NHL) was replaced with brick powder that was calcined at
three different temperatures: 800°C, 1000°C, and 1200°C, and ground to varying levels of fineness. The hydration reactions and mechanical
performance of each combination were analyzed through scientific and systematic methods. Isothermal calorimetry tests showed that brick
powder calcined at 800°C produced a significant increase in heat release during early curing. This was attributed to a strong pozzolanic
reaction, resulting in compressive strengths more than double that of pure NHL mortar after seven days. Further analysis using X-ray
diffraction (XRD) and thermogravimetric analysis (TGA) confirmed the formation of key hydration products such as stratlingite, hemi- or
mono-carboaluminate, and C4AH13, caused by the dissolution of aluminosilicates. Long-term pozzolanic activity also led to the near-complete
consumption of calcium hydroxide, which not only enhanced strength and durability but also reduced negative effects such as efflorescence, a
common concern in heritage conservation. These findings demonstrate that Wasul functions not only as a traditional filler but also as a
reactive binder. The results suggest a promising direction for developing specialized hydraulic binders suited to the repair and preservation of
Korea’s architectural heritage. |