• Economic and Environmental Geology
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• v.17 no.1
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• pp.57-78
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• 1984

The object of this study is to offer the standarized data for the design and calculating engineering cost of the rock excavation an the construction of the 3rd and 4th Seoul Subway lines From Jnauary to March in 1983, this study was carried out by the both methods of the field and laboratary studies. In the field, the geological survey in the entire area of Seoul City and sites on the subway lines were carried out and also a site measure of uniaxial compressional strength of rock masses by using Schmidt hammer was done. The labartory studies were carsied out by a study of preuions surveyes, microscopic studies of the mineral composition and degree of weathering of rocks, and measure of uniaxial compressional strengths Finally an engineering classification of each rock masses of South Africa council for Scientific and Industrial Research, CSIR, after Bieniawski, 1974. was done. In this method of classification 6 parameters such as strength of intact rock material, rock quality designation, spacing of fractures, condition of fractures, groundwater conditions, and the effect of fracture strike and dip orientation in tunnelling were used to evaluate rating of each rock mass.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.81-91
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• 2004

The host rock of standing sculptured Buddha in the Yongamsa temple was macular biotite granite, which has gone through mechanical and chemical weathering. The principal rock-forming minerals are quartz, plagioclase, alkali feldspar, and biotite, the last two of which have been transformed into clay minerals and chlorite due to weathering processes. The bed rock around the Buddha statue is busily scattered with steep inclinations that are almost vertical and discontinuous planes with the strikes of $N8^{\circ}E$. The major joints have the strikes of N4 to $52^{\circ}W$ and N6 to $88^{\circ}E$ and the dips of 42 to $89^{\circ}$. Especially thee development of the joints that cross the major joints causes tile structural instability of the rock. The host rock of the Buddha image is separated into many different rock masses because of the also many different discontinuity, which group accounts for about $12{\%}$ of the rock. Thus it's estimated that the bed rock has not only plane and toppling failure but also wedge failure in all the sides. Since the earth pressure and the inclination pressure are imposed on the body of the Buddha in the basement rock, it's urgent to give a treatment of geotechnical engineering for the sake of its structural stability. The parts where serious fractures are seen should receive the hardening process using the fillers for stones. It's also necessary to introduce a landfill liner system in order to reduce the ground humidity. The rock surface of the Buddha statue are partly contaminated by lichens and bryophyte. The joints have turned into earth, which promotes the growth of weeds and plant roots. Thus biochemical treatments should also be considered to get rid of the vegetation along the discontinuous planes and prevent further biological damages.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.285-289
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• 2005

The Cenozoic Era consists of two period , the Tertiary and the Quaternary Period. Weak rock types may include areas containing: 1) poorly cemented or uncemented sediments, 2) highly weathered rock, or 3) fault lines. Especially this paper deal with poorly cemented or uncemented sedimentary rocks in slope. Mechanical weathering is caused by physical processes such as absorption and release of water, and changes in temperature and stress at or near the exposed rock surface. It results in the opening of discontinuities, the formation of new discontinuities by rock fracture, the opening of grain boundaries, and the fracture or cleavage of individual mineral grains. Decomposition causes some silicate minerals such as feldspars to change to clay minerals. There was a strong negative correlation between water absorption and important engineering properties such as strength and durability.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1050-1056
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• 2008

Many cut slopes are situated on national highways. In this study, we chose rock slopes of moderated weathering grade to analyze general strength parameters of cut slopes. We analyzed the strength parameters of selected rock slopes by the experience method. Also, we arranged the strength parameters by area and rock types.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1285-1289
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• 2008

Increasing the flood control capacity's link that is enforcing to existing dam by unusual change of weather, While build planing construction by exiting spillway of tunnel type to dam, could know that part bed rock is formed as is different with design. Grasped topography of research area and geology state to definite distribution aspect of different bed rock, Place that achieved Surface geological Survey and correct Survey is difficult in some section enforced Electrical resistivity dipole-dipole investigation. Grasped stratigraphy distribution confirmation and fracture or weathering zone making out siding 2D-Resistivity Electrical resistivity diagram and Reverse analysis diagram, examining closely soil weathered rock rock's distribution state, established stability countermeasure plan

• Journal of Conservation Science
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• v.17 s.17
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• pp.5-18
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• 2005

Rock materials of the Stone Lantern in the Gwanchoksa temple was composed of dark grey granodiorite. This Stone Lantern is partly structural distortion as S-shape, especially, rocks of the upper supports and under the roof materials were highly deterioration due to the surface exfoliation, and strong secondary contaminations owing to the discoloration by oxidation of inserted iron plates between the rock properties, and white grey to dark black contaminants along the rain path way. Rock surface of the Stone Lantern occurred as partly green patches because of coated by algae, lichen and moss. This biological problems are need for cleaning and treatments. The Stone Lantern have to be considered to conservation method that can reduce weathering factors with long-term monitoring about environmental change for structural stability, surface degradation and mechanical weathering. Materials of the Stone Lantern and basement rocks of the area are consisted of same petrogenetic granodiotite based on occurrences, petrological and geochemical characteristics.

• Journal of Conservation Science
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• v.29 no.4
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• pp.321-332
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• 2013

Namwon Singyeri Maaeyeoraejwasang (Rock-Carved Seated Buddha Statue) is composed mainly foliated granite and is different metamorphic grade and weathering degree on rock location. As the results of deterioration evaluation, upper part of the buddha statue was estimated that granularity decomposition was serious and rock strength was lower than lower part. Furthermore organism assessed most effect of among weathering factors. Chl. a amount of organism species were calculated $0.2{\mu}g/cm^2$ of crustaceous lichen, $1.1{\mu}g/cm^2$ of foliose lichen, $2.3{\mu}g/cm^2$ of bryophyte. Organism was taken treatment in order of amount of Chl. a and pre-cleaning, dry cleaning, wet cleaning in sequence. It should be establish conservation plan that strengthening in consideration of lithology characteristics and setting in good condition environment to conserve long-term of Maaeyeoraejwasang.

• 보존과학연구
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• s.30
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• pp.79-91
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• 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.

• 한국문화재보존과학회:학술대회논문집
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• 2006.04a
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• pp.84-87
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• 2006

• Tunnel and Underground Space
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• v.19 no.2
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• pp.146-157
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• 2009

An experimental study of accelerated weathering on mudstone sample specimens from Haman, Gyeongnam was performed to investigate the variations of physico-mechanical properties of deteriorated rocks due to freeze-thaw weathering. Each complete cycle of freeze and thaw lasted 24 hours, comprising 2 hours of saturating in vacuum chamber, 8 hours of freezing at $-16{\pm}1^{\circ}C$ and 14 hours of thawing at room temperature. Total of 55 cycles of freeze-thaw were completed with measuring the index properties as well as geometries of microfractures. The measured specific gravity and P-wave velocity found to decrease with increasing freeze-thaw cycles. On the other hand, absorption ratio and effective porosity were continuously increased with increasing freeze-thaw cycles. It was found that the index properties of deteriorated sample specimen depend on its initial properties and flaws in rock. The size and density of the traces of the microfracture on slab specimen exhibited abrupt changes after 30 cycles of freeze-thaw weathering. The results obtained in this study show that the box fractal dimension($D_B$) given in this paper has the strong capability of quantifying the size and density of the microfracture.