A Study on the Manufacturing Properties of Soil Muralʹs Finishing Layer with Different Types and Concentration of Natural Adhesives

Abstract

In this study, we investigated the properties and manufacturing methods of soil mural finishing layers fabricated using animal glue, starch adhesive(wheat paste), and Dobak glue. We assessed the workability and weatherproofing properties of the earthen plaster and finishing layers fabricated using concentrations of 3%, 5%, 7% and 10% for each adhesive. The results showed that a mixture using 3% or 5% starch adhesive or 3% Dobak glue was suitable for constructing the finishing layer. For finishing layers made with animal glue, earthen plaster had poor workability. It was dry and easily broken as the concentrations of animal glue increased. However, specimens made with low concentrations of animal glue did not exhibit surface deterioration after a freezing-thawing test. Therefore, animal glue mixtures could possibly be used for constructing finishing layers in concentrations lower than 3%. Mixtures containing starch adhesive produced plasters 144 | 보존과학회지 Vol.34, No.3, 2018 with good workability. Additionally, starch adhesive enhanced compression strength. However, when starch adhesive was mixed at concentrations above 7%, the surface exhibited roughening and staining in freezing-thawing tests. When Dobak glue was used in mixtures, it enhanced compression strength, but concentrations above 5% produced specimens with surface cracking. For concentrations of 3%, there were no cracks and the specimens were stable after freezing-thawing tests, so concentrations below 3% of Dobak glue are suitable for constructing finishing layers. We expect this study will be useful for restoring the traditional technology of soil mural finishing layers and suggest using adhesives to construct the finishing layer.

Measuring Compressive Strength Characteristics of Soil‐Dobak‐Glue Mixtures over Curing Time

“…Dobak. Dobak (Pachymeniopsis elliptica [16,17]), glue weed (Gloiopeltis furcata), and jelly moss (Chondrus ocellatus) are seaweed species that are traditionally used to fabricate seaweed-based glue [18]. In Korea, Dobak, an algal species of the genus Grateloupia, has been primarily used to produce glue.…”

“…Subsequently, it was used in 2010 for the murals of Bogwangmyeongjeon in Wibongsa Temple in Wanju, Jeollabuk-do, and in 2011 for the murals of Uhwaru in Hwaeomsa Temple in Wanju, Jeollabuk-do. Dobak-glue was mostly used in concentrations of 1%-3% [18].…”

“…[25]. Moon et al [18] noted that organic materials such as Dobak-glue mixed with soil filled up fine-grained soil particles, thereby reducing pores and yielding densely compacted particle morphologies that enhanced the compressive strength. In the results of our study as well, the SS samples showed a higher compressive strength increase rate throughout the curing time owing to the stronger binding force arising from their dense aggregation compared with those of other samples.…”

Experimental Reinforcement Agent for Damaged Walls of Payathonzu Temple Murals in Bagan, Myanmar

“…Wall reinforcement studies conducted in Korea include studies on the physical properties according to the type of reinforcing medium mixed with the mixing ratio of the finishing layer or reinforcement agent for earthen murals (Kim and Jeong, 2008;Lee et al, 2013b;Moon, 2018).…”