• Journal of Conservation Science
• /
• v.31 no.4
• /
• pp.395-402
• /
• 2015

This study was considered utilization of hyperspectral image analysis for monitoring. Accordingly we applied to stone cultural properties to data correction methods, image classification techniques, NDVI computation techniques using hyperspectral image. As the results, hyperspectral image analysis was possible making detailed deterioration map, accurate calculation of deterioration rate, mapping of normalized difference vegetation index on the basis of reflectance of each materials. Therefore, hyperspectral image analysis will be used for effective monitoring techniques of stone cultural heritages.

• Journal of Conservation Science
• /
• v.31 no.3
• /
• pp.267-278
• /
• 2015

In this study, the elastomer cover, a new contact material, was developed to establish the customized ultrasonic measurement considering surface irregularities of stone cultural heritages. The cover exhibits high elastic force and wear resistance because it has tensile strength of 17MPa and elongation of 625%. In addition, as a result of comparative experiments for the seven types according to transducers and contact materials including the elastomer cover, rock surface irregularities significantly affect attenuation of ultrasonic velocity. The phenomenon was more noticeable in the chiseling finish and indirect transmission measurement rather than the dabbed finish and direct transmission measurement. However, the Type F using the exponential transducer and elastomer cover showed stable P-wave velocity and high amplitude regardless of the surface irregularities. This because the elastomer cover sufficiently sticks to surface irregularities and removes pores between a transducer and a rock specimen. Therefore, the Type F should be used for the ultrasonic measurement of stone cultural heritages with surface irregularities.

• 보존과학연구
• /
• s.30
• /
• pp.79-91
• /
• 2009

Stone cultural heritages are mostly situated in field, so they are damaged from mechanical, chemical and biological weathering, and their degree of strength is also weaken. Therefore, the scientific conservation of the stone cultural heritages are necessary in order to the long-term maintenance and safety conservation. In this study, we attempt to estimate on the field application of consolidants which are Wacker OH 100, Remmers KSE 300 and 1T1G according to the quality of the rocks. Based on the ultrasonic velocity, conditions of weathering damage before treatment are mainly ranked completely weathering condition (CW) or partly highly weathering condition (HW). After the first treatment, weathering damage conditions are changed by the high weathering condition (HW). These results shows that the internal pores of stone are filled with consolidant materials, so average ultrasonic velocities increases after treatment. And Remmers KSE 300 which is consolidant material is highest rate of increase of average ultrasonic velocities.

• The Korean Journal of Quaternary Research
• /
• v.21 no.1
• /
• pp.27-36
• /
• 2007

The severe damage of cultural heritages induced by natural hazards like heavy rain has been dramatically increased since 1990. The number of the repair works of stone heritage of 2005 was six times as many as those of 1986 year. Especially the ratio of the repair works of Gyeongsang Province and Jeolla Province stood 63% of those of all over the country. Since 1990, the typhoons usually struck the southern part of Korea and went northward. The heavy damage of stone heritages in two provinces was caused by them. We made a preliminary survey the stone heritages that exposed to the natural hazards on the basis of repair works of them and a field survey. The analysis results indicate that the natural hazards such as landslide and soil disaster of the stone heritages related to a sloping surface stood 58% of all kind of natural hazards. The reasons are caused by the 59 % of all the stone heritages distributed in a sloping surface resulted in natural hazards like landslide and soil disaster. The bases of stone heritages can be easily eroded by the surface water with high energy induced by heavy rainfall. Most of the stone heritages like Maebul were engraved on a natural rock wall(outcrop). But some of them engraved on rolling stones are very vulnerable in a change of a base condition caused by erosion and ground subsidence and they can be tilted or fell down. The distribution of the stone heritages vulnerable in natural hazard is related to that of the rainfall distribution compounded five typhoons after 1990. Most of them are included in level two on the rainfall distribution map except those of Taean peninsula and some of Gyeonggi Province. They seem to be rather related to the rainfall distribution of the Typhoon Olga.

• Journal of Conservation Science
• /
• v.27 no.2
• /
• pp.145-154
• /
• 2011

This research was to examine the biological pollution class by color of the polluted section and calculate the biological pollution coverages of 9 stone heritages in Korea, from June to November 2008. Three storied stone pagoda in Mulgeol-ri, Hongcheon, Three storied stone pagoda in Suta Temple and Stupa to Hongudang in Sutasa Temple showed 90% biological pollution coverage and each stone cultural heritages showed 15~23% range of Bryophyte coverage, proving severe biological pollution. The Four-lion three storied stone pagoda of Gwaeseok-ri, Three storied stone pagoda in Suta Temple and Stupa to Hongudang in Sutasa Temple showed the worst biological pollution class by color of class 5. Three storied stone pagoda in Chang-ri showed satisfactory level of class 2. The result of the correlation analysis between biological pollution class and the biological pollution coverage of lichen showed high correlation coefficient of 0.91, however, the correlation analysis between biological pollution class and bryophyte or aerial algae coverage showed the low correlation coefficient. Eight taxa among all the aerial algae, Cosmarium decedens, Chlorella ellipsoidea, Anabaena fertilissima, Botryococcus braunii, Chroococcus turgidus, Navicula cryptocephala and Xenococcus acervatus showed high correlation coefficient of 0.56~0.85 with biological pollution coverage of bryophyte, in the correlation analysis. The correlation coefficient between biological pollution coverage of lichen, Trebouxia sp. and Chroococcus varius, had a range between 0.43 to 0.50. The correlation coefficient between biological pollution coverage of aerial algae, Achnanthes laterostrata and Ulothrix zonata showed a range of 0.57 to 0.76. Since the aerial algae with high correlation between biological pollution coverage showed clear appearance tendency, they can be used as indicator.

• Journal of Korean Association for Spatial Structures
• /
• v.18 no.1
• /
• pp.45-53
• /
• 2018

Following the earthquake that shook the city of Gyeongju, Korea, in 2016, it became apparent that research on the safety of cultural heritages against the seismic hazards is necessary in Korea. Predictions of how historically significant stone pagodas would behave the earthquakes anticipated in near future, which are the subject of this study, is also required. In this study, the dynamic characteristics of 15 cultural heritage designated stone pagodas of Korea were investigated, including natural frequency and damping ratio, and the stiffness of the stone material and its contact area were determined using eigenvalue analysis by assuming the stone pagodas to be multi-degree-of-freedom structures. The results of this study enable the structural modeling of stone pagodas using a finite element analysis program and the method is expected to be useful in assessing the structural safety of stone pagodas against vertical loads as well as lateral forces, including earthquakes. Also, by identifying the dynamic characteristics of the structures, the results of this study can be utilized as a nondestructive testing method to determine the rigidity of cultural heritage structures and to identify inherent problems. The natural frequencies of the Korean stone pagodas were measured to be within 3.5~8.3Hz, excluding cases with distinct natural frequency results, and it was determined that the natural frequencies of the stone pagodas are influenced by various parameters including the height and joint stiffness of the structures.

• 한국문화재보존과학회:학술대회논문집
• /
• 2006.11a
• /
• pp.46-50
• /
• 2006

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.25 no.5
• /
• pp.1-13
• /
• 2022

The damages caused by landslides are increasing worldwide due to climate change. In Korea, damages from landslides occur frequently, making it necessary to develop the effective response strategies. In particular, there is a lack of countermeasures against landslides in cultural heritage areas. The purpose of this study was to spatially analyze the relationship between Buyeo-gun's cultural heritage and landslide susceptible areas in Buyeo-gun, Chungcheongnam-do, which has a long history. Nine spatial distribution models were used to evaluate the landslide susceptibility, and the ensemble method was applied to reduce the uncertainty of individual model. There were 17 cultural heritages belonging to the landslide susceptible area. As a result of calculating the area ratio of the landslide susceptible area for cultural heritages, the cultural heritages with 100% of the area included in the landslide susceptible area were "Standing statue of Maae in Hongsan Sangcheon-ri" and "Statue of King Seonjo." More than 35% of "Jeungsanseong", "Garimseong", and "Standing stone statue of Maitreya Bodhisattva in Daejosa Temple" belonged to landslide susceptible areas. In order to effectively prevent landslide damage, the application of landslide prevention measures should be prioritized according to the proportion belonging to the landslide susceptible area. Since it is very difficult to restore cultural properties once destroyed, preventive measures are required before landslide damage occurs. The approach and results of this study provide basic data and guidelines for disaster response plans to prevent landslides in Buyeo-gun.

• Journal of Conservation Science
• /
• v.25 no.2
• /
• pp.115-130
• /
• 2009

This study was focused on digital restoration and structural stability evaluation applying 3D scanning system of five-storied Magoksa temple stone pagoda in Gongju. For these, the digital restoration of the pagoda was completed using laser scan data which is measured 16 directions and data processing program of 7 stages. As a result of digital restoration, the overall height and width of stone properties showed a little difference in directions and the width of roof stones appeared very high difference of each floor. The width of pagoda body become smaller to the fifth floor, but gradual decrease rate showed irregular characteristics. Also, as result of 3D image analysis for structural stability evaluation, the displacement occurred toward northwest in second body stone to upper final stone except for central axis of the first body stone which inclines toward southwest. Such 3D image analysis is required quantification of survey method and should be applied to various field such as quantitative damage maps in order to utilize a conservation of stone cultural heritages, continuously.

• 보존과학연구
• /
• s.31
• /
• pp.103-120
• /
• 2010

Most of the important stone cultural heritage (National treasures and Treasures) in Korea are mainly located outdoor and considerably affected by the changes of the temperature, humidity and rainfalls. 541 of the stone cultural heritage are preserved as National treasure and Treasure. The pagodas occupy 187 remains and next 127 Buddha statues, 68 monuments, 60 stupas, and the others 74 stone cultural heritages. The shelter has been installed for one pagoda, 60 Buddha statues, 36 monuments and two stupas. The shelters are categorized in three shapes as traditional shape, modern shape, and others (tradition+modern). Approximately 100 of shelters that have constructed in traditional ways, and about nine of shelters have modern ways, and the only one has the combination shape of tradition and modern, which has been constructed since mid 1900s and repaired from the 1980s~2000s. Many researchers are studying for improvement of manners such as repairing, remodeling or removing of the shelter because problems have occured on shelters. Architectural form of traditional style of Korean timber building is respected, but it has problems on importing natural sunlight to the inside as well as ventilation and spacial problems. However, it needs to supplement policies to improve the positive roles of shelters such as prevention of artificial damage, blocking acid rain, and so on. For instance, the rock-carved Buddha Triad in Seosan, it had problems with viewing, contamination, and dew condensation on the surface. These problems decreased after dismantling the shelter, the space was made for improvement of viewing and dew condensation, and moisture problems were in better conditions. The velocity wind is an important factor in drying conditions on the surface of the rock, therefore the condition has improved after dismantling the shelter.