IEG 환경지질연구정보센터

응용지질학/지질공학․10월 26일(목)

2006 대한지질학회 추계학술발표회 초록집 • • 153

Synthetic Damage Estimation and Ultrasonic Measurement for Rock Properties of the West Stone Pagoda in the Gameunsaji

Temple Site, Korea

Myeong Seong Lee

ㆍChan Hee LeeㆍJiyoung KimㆍHeesoo Choi Department of Cultural Heritage Conservation Sciences, Kongju National University,

[email protected]

The West stone pagoda of the Gameunsaji temple site is the largest stone pagoda in Shilla Kingdom designated National Treasure No. 112 in Korea. This stone pagoda is get- ting lost its original features due to fracture, exfoliation, breaking-out, granular disintegra- tion and cavities on stone components. In addition, there are different materials such as pieces of iron, rock chips, concrete and cement mortar interposed between rock blocks which can cause secondary contamination and weathering on stones. Almost all stone ele- ments are affected by lichens, bryophytes and herbaceous plants.

In this study, deterioration map of the West stone pagoda was made out to assess the damage degree quantitatively. And then, deterioration rate in percentage was calculated for each facing direction from the basement part to the top of the pagoda according to weathering forms. The weathering degrees were finally compared to ones obtained by ul- trasonic measurement. Synthesizing all the results, it was concluded that basement part, the 3rd-floor body and roof part by vertical location of stone elements, and the eastern and southern faces by direction were more degraded than the any others. Fractures, exfoliation and granular disintegration were found as the most dominant weathering phenomena among weathering forms. Ultrasonic measurement also showed the same results about weathering degree.

Discoloration of the stone surface showed the highest intensity in the 3rd-floor body part of the pagoda while differences of discoloration by facing directions were not evident. The occupancy of microorganisms increased in basement and every roof part of the pagoda.

And besides, it was found that covering rate of microorganisms rose on western and north- ern faces by directions. To preserve this pagoda, all weathering phenomena and factors should be monitored and long-term master plan should be devised. Chemical and mechan- ical rock-reinforcing test should be also carried out. Next, it can be considered to substitute new stone elements for extremely weakened rock that can cause a structural problem and to apply conservation treatment removing microorganisms.

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