Characterization and durability assessment of fibre-reinforced tung oil lime putties for restoration. (June 2021)

• Record Type: Journal Article
• Authors: Wang, Shanwei; Yao, Wenjuan; Lu, Zhe; Wang, Sheliang; Li, Binbin; Liu, Bo
• Is Part Of: Journal of building engineering. Volume 38(2021)
• Publication Date: 2021-06
• Subjects: Tung oil lime putty -- Fibre-reinforced -- Water repellence -- Microscopic characteristics -- Salt freeze-thaw; Building -- Periodicals; 690.05
• DOI: 10.1016/j.jobe.2021.102241
• Languages: English
• ISSNs: 2352-7102

Abstract

Abstract: As a traditional organic-inorganic hybrid binding material, tung oil lime putty has a prospective application in ancient architecture restoration. In this paper, we prepared nine mixtures by adding hemp fibre to tung oil lime putties. The physical-mechanical characteristics, pore structure, mineralogy, infrared spectra and micromorphology of the curing-aged pastes were first determined. Then, the resistance of the specimens to the action of freeze-thaw and salt crystallization cycles was assessed. Tung oil acted as a modifier for lime carbonation and imparted water repellence. Paste-enriched oil exhibited a more compact microstructure and a significant reduction in water absorption. The fibre addition converted lime pastes to fibre-reinforced composites and promoted the carbonation progress of lime. Fibre reinforcement further hampered the development of cracks and pores, macroscopically characterized by the bending ductility in curing and a slight compressive strength increment after frost ageing of the salt solution. The composite with 1.0% fibre and 5% tung oil addition presented favorable resistance towards freeze-thaw cycles and salt crystallization degradation. Highlights: Characteristics of fiber-reinforced tung oil lime putties were studied. Hemp fiber admixture significantly improved the mechanical strength and ductility. Pastes durability in water and salt solution freeze-thaw cycles was fully evaluated. Pastes micromorphology and pore structure variation after weathering were tested. Reinforced pastes were more resistant to coupling effect of frost and salt erosion.