• Journal of the Korean GEO-environmental Society
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• v.5 no.2
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• pp.41-49
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• 2004

In this study, a newly modified soil nailing technology named as the SPN (Spiral Pipe Nailing) system, is developed to self drilling method can apply to ground which is hard to keep shape of bore hole. And limit equilibrium analysis with simplified trial wedge method while length ratio and bond ratio being altered was performed to evaluate slope stability considered of tensile strength and bending stiffness. Also, using $FLAC^{2D}$ program, superiority of the SPN system was compared to the GSN (General Soil Nailing) system about an example section. And effects of various factors related to the design of the SPN system, such as the type of drilling method and the bit, are examined throughout a series of the displacement-controlled field pull-out tests. As a result, the SPN system is better than the GSN system in slope stability because of having larger bending stiffness, tensile strength and unit skin friction. And results of simplified trial wedge method are similar to results of TALREN 97 program, commercial limit equilibrium analysis computer software, about an example section. Consequently, it will find out of that the SPN system reduce displacements and settlements in down excavation process as well as to increase the global stability.

• The Journal of Engineering Geology
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• v.19 no.3
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• pp.373-387
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• 2009

Many cultural heritages with various periods including the 'Three Kingdoms Period' were discovered in Chulmamyeon, Busan. Detailed geomorphological and geological investigation was performed due to archaeological importance of the study area. Aerial photographic analysis for geomorphology and analysis of vertical sedimentary sections to interpret the sedimentary characteristics were carried out. Many pebbles with specific features were discovered during the investigation. The characteristics and origin of the pebbles are analysed based on their size, rock type and shape. The study area is located in a relatively low and gentle slope compared with neighboring regions. The strong N-S trending lineaments may influence the topographic features and the distribution of wells discovered in this area. The exposed sections during excavation are divided into several layers depending on colors and materials included. Some of the layers may be developed not by nature but by human activities. The similarity of the pebbles indicates that these pebbles may artificially be collected or produced for a specific purpose. This study shows that geomorphology and geology can be important in location and development of archaeological sites. The analysis and interpretation for the origin of the pebbles indicates that geological studies can be helpful to interpretation of archaeological studies.

• The Journal of Engineering Geology
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• v.15 no.3
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• pp.257-268
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• 2005

In situ rock mass is generally heterogeneous and discontinuous, with varying degrees of strength along the planes of weakness. The planes of weakness such as joints, faults, cracks and bedding planes, control the strength and deformation characteristics of the rock mass. Subsequently, the stability of underground opening depends upon the spatial distribution of discontinuities and their mechanical properties in relation with geometrical shape of openins as well as the mechanical properties of intact rock materials. Understanding the behaviour of a discontinuous rock mass remains a key issue for improving excavation design in hiかy stressed environments. Although recent advances in rock mechanics have provided guidelines for the design of underground opening in isotropic rock mass, prediction and control of deformation in discontinuous rock masses are still unclear. In this study, parametric study was performed to investigate the plastic zone size, stress distribution and deformation behavior around underground opening in a discontinuous rock mass using a continuum joint model. The solutions were obtained by an elasto-plastic finite difference analysis, employing the Mohr-Coulomb failure criteria. Non-associated flow rule and perfectly plastic material behavior are also assumed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.175-181
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• 2020

This paper suggests a proper hydraulic filling method in downtown areas. Road subsidence on roadways and sidewalks in downtown areas can result in vehicle damage and casualties. The representative cause of road subsidence is the fraudulent construction in nearby construction sites. A deficiency of excavation restoration causes approximately 25~49% of subsidence. This is performed by equipment or manpower. Hydraulic filling is used in backfilling narrow pipe conduits and spaces between structures. On the other hand, standard specifications and quality assurance standards regarding hydraulic filling principles and construction conditions are insufficient. Therefore, in-door model experiments on hydraulic filling principles, backfilling material, and compaction efficiency were performed. This paper suggests guidelines by investigating and analyzing construction status. In conclusion, thrown backfilling material has a particle size distribution and permeability coefficient as major factors, and detailed standards of the factors are suggested. To improve the compaction efficiency, 90% or more, compaction by the floor should be in units of 0.3m while ensuring a lower drainage layer. When an H-shape stabilizing pile is pulled out after filling, additional hydraulic filling should be in the disturbance range.

• Journal of the Korean Geophysical Society
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• v.9 no.1
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• pp.47-62
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• 2006

More than 70% of Korean Peninsula is consisted of mountains, so that lots of roads, rail-roads and tunnel,which play a pivotal role in the industry activity, are existed along the rock-slope and in the rock-mass. Thus,it is urgent that tegration of management system through the optimum survey and design of rock-slope excavation, proper stabilization method and database of rock-slope. However, conventional methods have shortcoming with the economy of survey time and human resources, and the overcome of difficulties of approach to the in-situ rock-slope. To overcome the limitation of conventional method, this paper proposed the development of remote measurement system using Terrestrial Laser Scanning System. The method using Terrestrial 3D Laser Scanning System, which can get 3D spatial information on the rock-slope and2)Dept. Geosystem Engineering, Kangwon National University, Korea tunnel, has an advantage of reduction of measurement time and the overcome of difficulties of approach to the in-situ rock-slope/dam/tunnel. In the case of rock-slope, through the analysis of 3D modeling of point-cloud by Terrestrial Laser Scanning System, orientation of discontinuity, roughness of joint surface, failure shape and volume were successively achieved. in the case of tunnel face, through reverse-engineering, monitoring of displacement was possible.

• Journal of the Korean Geotechnical Society
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• v.29 no.3
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• pp.51-60
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• 2013

The slime, deposited in the bored pile due to falling soil particle, reduces the bearing capacity of bored pile and thus the stability of construction also decreases. The weight pendulum and iron have been used for estimating the slime thickness based on the subjective judgment and thus the previous method has a limitation of reliability. The objective of this paper is to suggest the method for estimating the slime thickness by using characteristics of electrical resistivity as scientific method. The temperature-compensation resistivity probe (TRP), which has a conical shape and the diameter of 35.7mm, is applied to the measurement of the electrical resistivity in the borehole during penetration. The field tests are carried out for estimating the slime thickness in the application site of bored pile. The slime thickness is calculated through the difference between excavation depth of borehole and measured data. Furthermore, the laboratory tests are also conducted for investigating effects of casing, time elapsing and relative density by using the specimen of slime. The laboratory test supporting the suggested method is reasonable for determining the slime depth. The paper suggests that the electrical resistivity method may be a useful method for detecting slime thickness and the method is expected to be applicable to various sites of bored piles.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.4 s.31
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• pp.27-33
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• 2004

Recently, as a part of NGIS project, cultural-assets digital map is produced by cultural properties administration and local autonomous entities. Cultural-assets unified GIS(Geographic Information System) is essential to cultural properties managers md other organizations which are executing land related business for appling it at planning stage. With explosive national land developments, it has been obligated to implement surface survey by the cultural properties protection Art. In this paper, the authors used the district of Sachon city and made 3D terrain model using digital map which is made of 1/5000 stale. Moreover, the authors improved to RDBMS(Relational Database Management System) structure and remodeled the existing DB design in detail, and also tried recovery of past sea level, based on researches about the water level of southern area. By recover past sea level. the shell mound, apart from lever is actually near lever at past, and it make sure its nature. The authors suggested to realize shape and kind of remains which have 3D information of accuracy and actualization from surface-surveying to excavation.

• Journal of Conservation Science
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• v.28 no.1
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• pp.21-27
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• 2012

In the Chosun period, the noble class usually buried the dead bodies in the lime-covered tomb. Recently their costumes are excavated while maintaining the shape. However, the textiles discovered from the inside have been degradated by a body and moisture. To conserve these textiles one of the most important thing is how to clean these textiles right after the excavation. The purpose of this study is to examine the effects of wet cleaning to minimize the color change of textile remains. For this purpose, silk and cotton were dyed with natural dyes (7 red, 1 blue, 6 yellow, 4 green and 4 purple colors), then they were kept for 6 months with pork meat at $10^{\circ}C$, and were washed by four cleaning solutions (water, anionic surfactant (SDS), non-ionic surfactant (Triton X-100) and natural surfactant (saponin)) at $20^{\circ}C$ and $40^{\circ}C$. The color change was evaluated by color difference (${\Delta}E$) between non-treated and after washed samples. From the results, it was found that the color changes are significantly different depending on the washing temperature, textile material, the cleaning agents and the type of dyes.

• Conservation Science in Museum
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• v.14
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• pp.23-28
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• 2013

This paper aimed to show the whole conservation process of the human shaped terra cotta mask that was excavated from one of construction sites at Jungcheon-ri, Geumsan-myeon, Jinju. This mask was X-rayed to get the correct making techniques and there are 4 holes on the top of the head and each diameter of the 3 holes is exact and the other hole is different from the three. The long and sharp shape of the nose is in trapezoid which was separately made with clay and put on (the face). It's found that there are round grooves each around upper and down lips. (upper in length: 10mm, down in length: 6 mm). All restoring materials and adhesives used for restoration to associate each piece are reversibility materials. According to a few points on buried bones of animals distributed around the sites, holes and grooves on the top of the head, ears and teeth to wear something, it academically presumes that this mask could be possibly used for the group ritual. Especially, the whole procedure from excavation to scientific conservation process resulted to have a special exhibition to give the public new eyes how the exhibition realizes to the public.

• Korean Journal of Heritage: History & Science
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• v.42 no.2
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• pp.110-133
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• 2009

This study is on the types and characteristics of foundation and basestone which can be seen in remains of Baekje and Silla in beginning study of them in ancient Korean architecture. This is a close investigation that division of the shape of the basestone and the type of Jeoksim(積心, the supporting part under the basestone) and foundation under the ground. Also it can be seen that the difference of construction technique and the relation with each part. The research objects are the remains of temples which had been excavated or are been excavating now in Baekje area and in Silla from 6th to 8th century. Results of research published in north Korea are quoted for the remains in Goguryeo being unable to be seen as they are in north Korea. If it had been possible to visit the sites, the materials would have been collected from the direct investigation. Otherwise they are collected from the excavaion results published. After that the basestone and the foundation could be divided according to several types. Also each types can be compared and studied according to times and building use. The results are follows. There are some different characteristics between Baekje and Silla in the technique of foundation, jeoksim, and basestone. Through them it is possible that the arhitectural technique of Baekje had been introduced to not only wooden pagoda in the erection of hwangryongsa temple. These results are considered limited in a few remains grasped the characteristics so it should be complemented continuously as the outcome of excavation of architectural remains will be accumulated to.