Effect of Lime Fiber Co-Aging Process on Properties of Lime Statue Materials

Lime statue, a traditional decorative technique popular in China and Southeast Asia, employs metal/wood framing and lime mortar shaping. The mortar, which contains lime, fibers, and organic additives, is key to durability. Despite this, its processing remains understudied. This work focused on the co-aging process of lime and fibers in the preparation of lime mortar and its impact on material properties. The results showed that lime-fiber co-aging dissociated fiber bundles into microscopic fibers in hot lime slurry, effectively removing lignin and hemicellulose. This process roughened the fiber surface for better fiber-lime matrix adhesion, and also ensured a more uniform distribution of fiber in the lime matrix and prevented fiber clustering. This enhanced the solidified lime mortar;s mechanical and durability properties. Moreover, lignin in the leachate acted as a water reducer, improving mortar workability and density while lowering the shrinkage and water absorption of the solidified mortar. However, polysaccharides released from the fibers delayed lime carbonation, hindering early strength development of the mortar. Overall, the mortar prepared with fibers soaked in 80°C lime water and its leachate exhibited the best comprehensive performance, with optimal workability, minimal shrinkage, and low water absorption, slightly compromised early strength.