• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.90-99
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• 2004

Stone column is one of the soft ground improvement method, which enhances ground conditions through ground water draining, settlement reducing and bearing capacity increasing complexly by using crushed stone instead of sand in general vertical drain methods. In recent, general construction material, sand is in short of supply, because of the unbalance of demand and supply. Also, the bearing capacity improving effect of stone column method is needed in many cases so the bearing capacity estimation is considered as important point. Nevertheless, adequate estimation methods to predict bearing capacity of stone column considering stone column and improving ground behavior reciprocally is not yet prepared. To contribute this situation, bearing capacity behavior of stone column were simulated as numerically on various property cases of crushed stone and surrounded ground. Through the numerical analysis of simulation results, bearing capacity behavior prediction formula was suggested. This formula was verified by comparing the prediction result with in situ test.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.427-434
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• 2006

The stone pagoda on the Miruksa temple site has a high value as architectural history, because this stone pagoda is one of the oldest and grandest stone pagodas which remain in Korea today. However, this stone pagoda has remained only six stones of the northeastern part, becased this stone pagoda was collapsed at past. Therefore, it is important to know the original structure and form of this stone pagoda. Hypotheses about collapse cause of this stone pagoda are presented as four cases: collapse by earthquake, collapse by fragility of ground, collapse by durability reduction, and collapse by lightning, On the basis of these four collapse hypotheses in this study, we investigate collapse phenomenon through the structural analysis using discrete element method and evaluate collapse causes of this stone pagoda.

• Geomechanics and Engineering
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• v.12 no.3
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• pp.417-439
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• 2017

The stone columns are increasingly being used as a soil improvement method for supporting a wide variety of structures (such as road embankment, buildings, storage tanks etc.) especially built on soft soil. Soil improvement by the stone column method overcomes the settlement problem and low stability. Nevertheless, stone column in very soft soils may not be functional due to insufficient lateral confinement. The required lateral confinement can be overcome by encasing the stone column with a suitable geosynthetic. Encasement of stone columns with geogrid is one of the ideal forms of improving the performance of stone columns. This paper presents the results of a series of experimental tests and numerical analysis to investigate the behavior of stone columns with and without geogrid encasement in soft clay deposits. A total of six small scale laboratory tests were carried out using circular footing with diameters of 0.05 m and 0.1 m. In addition, a well-known available software program called PLAXIS was used to numerical analysis, which was validated by the experimental tests. After good validation, detailed of parametric studies were performed. Different parameters such as bearing capacity of stone columns with and without geogrid encasement, stiffness of geogrid encasement, depth of encasement from ground level, diameter of stone columns, internal friction angle of crushed stone and lateral bulging of stone columns were analyzed. As a result of this study, stone column method can be used in the improvement of soft ground and clear development in the bearing capacity of the stone column occurs due to geogrid encasement. Moreover, the bearing capacity is effected from the diameter of the stone column, the angle of internal friction, rigidity of the encasement, and depth of encasement. Lateral bulging is minimized by geogrid encasement and effected from geogrid rigidity, depth of encasement and diameter of the stone column.

• Journal of the Korean Institute of Rural Architecture
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• v.7 no.3
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• pp.109-118
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• 2005

This study is to find out the plan intention of the central space through visual analysis on the east and west stone pagodas relative to a main Buddhist hall, and the relation between the stone pagodas in Hwaeomsa.(華嚴寺) According to the analysis of it in this study, we make conclusions as follows; 1) The east and west stone pagodas was arranged with overlapping each Daeungjeon(大雄殿) and Gakhwangjeon(覺皇殿) for the view of a specific viewpoint, on the right of Bojeru(普濟樓). 2) The centering around a compositive axis which connect Gakhwangjeon, stone lantern, and stairs, the axis of two stone pagodas is not coincident. 3) Courtyard in Hwaeomsa is separated by high a stone wall for reinforcement, but it is integrated into visual perception owing to height of two stone pagodas connected visual line to Daeungjeon and Gakhwangjeon.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.6
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• pp.19-27
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• 2018

The stone pagoda structure is treated as a discontinuous masonry structure, and the contact surface characteristics between stones is a very important factor in the discontinuum behavior analysis. So, it is necessary to find out material and structural characteristics of stone contact surface to perform the structural analysis for safety evaluation. Accordingly, it is important to analyze the material properties of stone surface and secure the structural characteristics through various contact surface states. Therefore, in this study, various test specimens applying the filler between the surface roughness and the stone in the contact surface treatment technique of the stone pagoda were manufactured, and compression test and shear test were carried out. Also, we analyzed the material and structural characteristics of the stone contact surface through the comparison of experimental results.

• Journal of Korean Association for Spatial Structures
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• v.14 no.2
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• pp.41-50
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• 2014

The stone pagoda of Mireuk temple site is currently restoring through the repairing process. This stone pagoda has the various construction types in the inner and outer space. Therefore, the stress concentration and structural behavior need to be considered through the analysis of various construction patterns. To this end, this study presents the structural modelling and analysis considering the discrete element analysis technique to solve the discontinuum behavior between the stone elements. Also, this study performs the structural performance evaluation through the various design variables for the safety of stone pagoda. Through the analysis results, we can find out the small stress concentration in the several members. But, because the stresses and displacements are relatively small, we can secure the safety of the whole structure.

• Journal of Korean Association for Spatial Structures
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• v.20 no.4
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• pp.101-110
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• 2020

In case of stone pagoda structures, the various construction types appear, and various damages occur due to exposure to the outdoors for a long time. Such damages can be classified into non-structural damages and structural damages. However, studies for the effects of structural damages on stone pagoda structures are insufficient. Accordingly, this study intends to perform structural modeling and structural analysis according to structural damages of stone pagoda structure, and to perform risk analysis through the fragility curve. So, we expects that this study gives a great contribution to the preservation and maintenance of stone pagoda structures under the various structural damages.

• Journal of the Korean GEO-environmental Society
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• v.5 no.1
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• pp.75-84
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• 2004

Stone column is one of the soft ground improvement method, which can enhance ground conditions such as the settlement reduction and the increasement of bearing capacity with applying the crushed stone instead of sand. In recent, general construction material, sand is in short of supply. Therefore, the bearing capacity improvement by the stone column is considered as the alternative method needed in many cases so the bearing capacity estimation is considered as important point. Nevertheless, adequate estimation methods to predict bearing capacity of stone column considering stone column and improvement effect of ground is not yet prepared. For the analysis of above mentioned points, the behavior of stone column were simulated as numerically on various property cases of crushed stone and surrounded ground. Through the numerical analysis of simulation results, the formula for the bearing capacity estimation of stone column was suggested. This formula was verified by comparing the prediction result of in situ test.

• Journal of the Korean Institute of Rural Architecture
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• v.4 no.1
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• pp.71-86
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• 2002

This research aims to illustrate the structure of the ancient Korean wooden buildings by a comparative study of the historical resources such as stone remains, wall paintings historiographies and excavations. As stone pagodas are the most typical stone remains, I selected for analysis some stone pagodas which contain architectural elements and results of the study are as follows: 1) The number of stories and structural modes of the base stone part show the wooden architectural aspects: they have one or two stories and their base part is constructed in the mode of assembling rectangular stones. 2) The body of the pagoda contains such architectural elements as pillars, door and windows, crossbeams, balcony, bracket sets. 3) The roof of the stone pagoda contains such architectural elements as eaves, roofs and modes of stone assembling. The results inferred through this research could be of help for further comparative studies with the other secondary materials by providing basic knowledge for it.

• Journal of Technologic Dentistry
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• v.34 no.3
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• pp.227-235
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• 2012

Purpose: This study compared the surface hardness (Vickers) and microstructural characteristics between a type IV stone with and without die hardening treatment, a polyurethane die material. Methods: Materials used were a type IV stone(MG Crystal Rock), two die hardeners (Hardening bath, Epox-it), and a polyurethane resin material(Polyluck). Six specimens per group were prepared according to manufacturer's directions. The prepared specimens were tested by means of hardness test, one-way ANOVA analysis, scanning electron microscopic(SEM) observations and energy dispersive spectroscopic(EDS) analysis. Results: In the hardness test and its statistical analysis, there was no significant difference in the surface hardness between a type IV stone and type IV stone with die hardener coating, type IV stone mixed with an epoxy like material instead of water. In contrast, polyurethane resin material exhibited significantly greater surface hardness than other specimen groups (p<0.05). Conclusion: By considering the results of the hardness test, SEM observations and EDS analysis, although the die hardeners on type IV stone did not show remarkable improvement in surface hardness, the die hardener coating on the surface of type IV stone material did show decrease of microporous and improvement of surface defects.