〔報文〕土質遺構露出展示保存のための基礎的研究―土中水のポテンシャル制御による遺構安定化の試み―

In this study, conservation method that prevents collapse of soil structural remains caused by drying and precipitation of salt by controlling the water potential gradient was examined. At Miyahata site located in Fukushima city, soil boring was performed to estimate the ground structure. In laboratory experiments, some parameters that determined water retention curve and hydraulic conductivity of unsaturated soil were estimated by evaporation method and inverse analysis with HYDRUS-1D. Based on the ground structure and unsaturated hydraulic properties obtained, water movement in vertical direction was simulated by numerical analysis. As a result of numerical analysis, it was revealed that the soil of remains would continue to dry. Then, the changes in water potential gradient caused by timely infiltration were also simulated. As a result, it was revealed that downward gradient of water potential and zero-flux plane could be produced alternately. By repeating infiltration and evaporation in a short span, it was revealed that deterioration of the remains caused by drying and precipitation of salt could be inhibited

〔報告〕水浸出土木製遺物の保存処理における溶媒蒸発を用いた薬剤含浸の効率化の可能性

In the conservation treatment of waterlogged wood, impregnation of a solute into wood for stabilization can be processed by immersing the whole wood in a chemical solution. However, since the penetration of solutes by diffusion is generally very slow, the efficiency of the process is severely limited. Though various types of chemicals have been proposed so far as impregnant for waterlogged wood in order to improve the efficiency of the impregnation process, the principle of impregnation itself has not changed significantly. In the pr esent study, the efficient method of impregnating chemical into waterlogged wood was examined based on the principle which was different from the conventional one. As a result of the preliminary experiment with PEG for impregnant, it is suggested that permeation and accumulation of solutes by advection can be efficiently progressed by immersing the waterlogged wood in the solution with the upperpart of it exposed to the air and controlling temperature and evaporation rate of the solvent. Also, the dimensional stability of the wooden sample after solidification of PEG was excellent. The experiment also suggested that there is the necessity of controlling the solvent evaporation rate properly so as not to exceed the rate at which the solution is absorbed into the wood. It is considered that the permeability of the solution inside wood is affected by the structure of wood, the degree of deterioration of wood and the viscosity of solution

平城宮跡遺構展示館における露出展示遺構の保存環境に関する研究

京都大学0048新制・論文博士博士(工学)乙第13012号論工博第4137号新制||工||1650(附属図書館)32940京都大学大学院人間・環境学研究科文化・地域環境学専攻(主査)教授 鉾井 修一, 教授 髙橋 大弐, 教授 山岸 常人学位規則第4条第2項該当Doctor of Philosophy (Engineering)Kyoto UniversityDFA