歴史的石造物の保存のための超可塑剤のない天然水力石灰の収縮を緩和する:組成,固化,膨張剤の効果
1College of Architecture and Urban Planning, Tongji University, No. 1239 Siping Road, Shanghai 200092, China.
Materials (Basel, Switzerland)
|August 28, 2025
まとめ
自然液体石灰 (NHL) の接合物収縮は,歴史的な石造りの修理における課題です. この研究では,NHLグルーツの組成を最適化し,酸化カルシウム (CaO) ベースの膨張剤が効果的に収縮を軽減し,吸収度が高い基板では制御された使用が推奨されています.
科学分野:
- 建築材料科学
- 遺跡保全工学
- 地質工学
背景:
- 破裂は歴史的な石造りの構造における主要な劣化メカニズムです.
- 自然液体石灰 (NHL) の接着剤による接着剤は,遺産材料との互換性のために好まれている重要な介入です.
- 固化中のグルーツの収縮は,しばしば,石造りの保存におけるNHLグルーティングの有効性を損なう.
研究 の 目的:
- 超可塑剤のないNHLグルーツの収縮特性について調査する.
- 最適なグルーツの組成を特定し,膨張剤と基板特性の収縮への影響を評価する.
- 歴史的な石造りの効果的な接合のための材料設計戦略を提供する.
主な方法:
- 接合物の組成,膨張剤,および基板の性質の実験的調査.
- 水分,結合物質,総量比率を最適化するために,タグチの方法の適用.
- 28日間の固化と接合のシミュレーション実験後の収縮量測定
主要な成果:
- タグチの方法により,最適化されたグルーツの組成が特定されました.
- カルシウム酸化物 (CaO) ベースの膨張剤は,NHLグルーツの収縮を緩和するのに最も効果的であることが判明しました.
- サブストラットの水吸収はグルーツの収縮に大きく影響を与えます.高毛細血管水吸収 (> 25 kg/m2 h1/2) のサブストラットでは,拡張剤の制御された使用が不可欠です.
結論:
- 最適化されたNHLグルーツ製剤は 縮小を効果的に補うことができます
- 膨張剤の選択と投与は,基板の特性,特に水吸収を考慮する必要があります.
- この発見は 耐久性や性能を向上させるための 実践的な戦略を提示しています
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