• International conference on construction engineering and project management
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• 2009.05a
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• pp.1396-1403
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• 2009

The Ministry of Construction and Transportation (MOCT) has been constructing a nationwide soil information DB since 2000, as basic data for the construction of 'underground geographical information,' a project under the 2nd National Geo-spatial Information System (NGIS) master plan. The inputted soil information includes not only underground conditions such as the layer depth, type, color, and groundwater level, but also engineering information that can be applied to construction work design, such as on the standard penetration test and the compression test. It is difficult to use this information in soil analysis and design, however, because only the test results are currently available. A web-based geo-spatial information system was developed in this study to facilitate the effective application of the soil information database (DB). First, the space information, layer information, and engineering test information were loaded from the soil information DB in real time, and the earth volume, bearing capacity, and settlement were calculated to develop a web client that will evaluate the ground softness and liquefaction. It seems that the soil information DB can be actively applied to the planning and design of construction works using this system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.5
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• pp.50-59
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• 2006

This study was initiated to investigate soil chemical properties under different soil systems. Data such as soil acidity(pH), electrical conductivity(EC), organic matter content(OMC), and cation exchange capacity(CEC) were analyzed with samples from multi-layer, USGA, and mono-layer systems. N, P, K and micronutrients were also measured. Multi-layer system was built up to 60-cm depth with rootzone layer, intermediate layer and two drainage layers. USGA system 45 centimeters deep was constructed with rootzone layer, intermediate layer and drainage layer. Mono-layer system, however, was made only with a 30-cm rootzone layer. Differences were observed in soil pH, EC, OMC, CEC and micronutrients. Soil pH was acceptable for turfgrass growth a year after establishment, being 5.5 to 6.5 in the study. Differences were greatly observed for EC among soil systems. Values of EC for multi-layer, USGA, and mono-layer systems were 39.79, 31.26 and 103.54 uS/em, respectively. The increase rate was approximately 4 to 8 times greater with mono-layer system than those with other two systems. Therefore, it was necessary to avoid micronutrient deficiency such as Fe, Mn etc. through an effective management program in mono-layer system because of its faster potential feasibility of salt accumulation. The greatest OMC was associated with USGA system, being 0.97% which was 11% over that of the other systems. Slight differences were observed for CEC among them. Mono-layer system produced 1.45 me/100g, 10.3% and 8.9% lower in CEC than those of multi-layer and USGA system, respectively. Micronutrients such as Fe, Zn, and Mn etc. were below the level required for turf growth, regardless of soil systems. It was considered that one year after turf establishment was not enough to build up micronutrients in sand-based soil systems to the normal level for a turf growth. These results demonstrate that intensive management program including grow-in concept fertilization should be integrated into sand-based soil systems, even after a year in establishment. Regular nutrient monitoring by soil analyses is a strong necessity to decide the kinds and amount of fertilizer. Also, strategic management program must be selectively employed according to sports turf soil systems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6C
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• pp.385-393
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• 2006

Soil nailing is a reinforcement method used for stabilizing excavated walls or slopes. Due to its much advantages such as ease of construction and economical efficiency, use of soil nailing is increased. However, the soil nail has much disadvantages for use in urban area. The soil nail needs to be installed inevitably beyond private land boundary, which causes rent for use. For this reason, removable soil nailing system was developed. However, the removal rate of this system is just about 50￠¦70%. To resolve this problem, the Fiber Reinforced Plastic (FRP) soil nailing system which does not need to be removed and allows for the installation beyond private land, is developed. In this paper, through theoretical and experimental studies in laboratory and field such as prototype tests, pullout tests, we evaluate the stability and behavior characteristics of the FRP soil nailing system. And, numerical analyses using FLAC2D were performed with respect to various soil conditions, where prototype test for excavation wall and pullout tests were carried out. As a result of this study, the FRP soil nailing systems show similar behavior characteristics with those of removable soil nailing system. Finally, considering the serviceability and mechanical stability of FRP soil nailing systems, it is enough to be used as a good alternative of general soil nailing system.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.3-5
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• 2005

The objective of this research was to develop a framework of the Soil Environment Information Management System (SEIMS). In this study, we found that the SEIMS needs to be consisted of three sub-systems (i.e., information input system, DB system, and opening to the public system), which is operated on the Web-GIS basis. Also, we suggested structure and detailed items for each sub-system which are acceptable under the basis of current legal and institutional system. Furthermore, we made several suggestions for future-oriented system. Further researches need to be pursued for developing efficiently the SEIMS, such as 1) DB standards for the SEIMS, 2) guidelines for each cleanup phase, 3) improvement of the SEIMS for groundwater quality, and 4) integrated SEIMS for both soil and groundwater system.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.184-191
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• 2010

This paper proposes the shaking table testing method for replicating the dynamic behavior of soil-structure interaction (SSI) system, without any physical soil model and only using superstructure model. Applying original SSI system to the substructure method produces two substructures; superstructure and soil model corresponding to experimental and numerical substructures, respectively. Interaction force acting on interface between the two substructures is observed from measuring the accelerations of superstructure, and the interface acceleration or velocity, which is the needed motion for replicating the dynamic behavior of original SSI system, is calculated from the numerical substructure reflecting the dynamic soil stiffness of soil model. Superstructure is excited by the shaking table with the motion of interface acceleration or velocity. Analyzing experimental results in time and frequency domains show the applicability the proposed methodologies to the shaking table test considering dynamic soil-structure interaction.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.4 s.31
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• pp.13-19
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• 2004

It has been a common practice to use manually processed soil maps in planning of land readjustment. This study is intended to develop a geographic information system for computerized processing of soil maps. The pilot region of land readjustment for this study was set at a mountain area with diverse formation of soil. Cadastral maps were employed for the basis map, and the main map was prepared using the information obtained from in-situ soil survey and laboratory tests. The detailed soil maps were drawn using the geographic information system, and analyzed and compared with manually processed maps. The soil maps, in conjunction with a computer program of land readjustment design, can be applied in estimation of soil works appropriate for the given soil condition, and also in selecting the efficient construction equipments.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.137-144
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• 2005

Recently a pressurized grouting soil nail is demanded due to problems beyond of economical and engineering purpose. In this study, a newly modified soil nailing technology named as the PGSN (Pressurized Grouting Soil Nailing) system is respected to reduced displacements of nails and increase of global slope stability. And effects of various factors related to the design of the PGSN system, such as the length of the soil nail, injected pressure and W/C ratio of cement grout in the pressurized grouting soil nail are examined throughout a series of the displacement-controlled field pull-out tests. Displacement-controlled field pull-out tests are performed in the present study and the volume of grouting are also evaluated based on the measurements. In addition, both short-term and long-term characteristics of pull-out deformations of the newly proposed PGSN system are analyzed and compared with those of the general soil nailing system by carrying out the stress-controlled field pull-out tests. From the pull-out characteristics of pressurized grouting soil nails, it is found that the effect of the length of the soil nail, injected pressure and W/C ratio of cement grout are important parameters.

• International Journal of Computer Science & Network Security
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• v.23 no.4
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• pp.146-150
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• 2023

In areas where water is scarce, water management is critical. This has an impact on agriculture, as a significant amount of water is used for that purpose. Electronic measurement equipment are essential for regulating and storing soil data. As a result, research has been conducted to manage water usage in the irrigation process. Many equipment for managing soil fertility systems are extremely expensive, making this type of system unaffordable for small farmers. These soil fertility control systems are simple to implement because to recent improvements in IoT technology. The goal of this project is to develop a new methodology for smart irrigation systems. The parameters required to maintain water amount and quality, soil properties, and weather conditions are determined by this IoT-based Smart irrigation System. The system also assists in sending warning signals to the consumer when an error occurs in determining the percentage of moisture in the soil specified for the crop, as well as an alert message when the fertility of the soil changes, since many workers, particularly in big projects, find it extremely difficult to check the soil on a daily basis and operate agricultural devices such as sprinkler and soil fertilizing devices.

• Structural Engineering and Mechanics
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• v.88 no.3
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• pp.273-285
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• 2023

This study examines how the interaction between soil and a wind turbine's supporting system affects the optimal design. The supporting system resting on an elastic soil foundation consists of a steel conical tower and a concrete circular raft foundation, and it is subjected to wind loads. The material cost of the supporting system is aimed to be minimized employing various metaheuristic optimization algorithms including teaching-learning based optimization (TLBO). To include the influence of the soil in the optimization process, modified Vlasov and Gazetas elastic soil models are integrated into the optimization algorithms using the application programing interface (API) feature of the structural analysis program providing two-way data flow. As far as the optimal designs are considered, the best minimum cost design is achieved for the TLBO algorithm, and the modified Vlasov model makes the design economical compared with the simple Gazetas and infinitely rigid soil models. Especially, the optimum design dimensions of the raft foundation extremely reduce when the Vlasov realistic soil reactions are included in the optimum analysis. Additionally, as the designated design wind speed is decreased, the beneficial impact of soil interaction on the optimum material cost diminishes.

• Journal of the Korean GEO-environmental Society
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• v.5 no.3
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• pp.51-60
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• 2004

In Korea there are recently many attempts to expand a temporary soil nailing system into a permanent soil nailing system since the first construction in 1993. In the soil nailing system, the rigid facing walls act on restraining the deformation of the ground. These are purposed to minimize the damage of adjacent buildings or underground structures. In Korea, to minimize the relaxation of the ground, the soil nailing system in the downtown area is often used experientially together with braced cuts, sheet pile walls, soil cement walls (SCW), or jet grouting walls. However, for the conservative design, the confining effects by the stiff facing have been ignored because the proper design approach of considering the facing stiffness has not been proposed. In this study, various laboratory model tests are carried out to examining the influence the rigidity of facings on the global safety of soil nailing system. Also, the parametric studies using the numerical technique as shear-strength reduction technique are carried out. In the parametric study, the thickness of concrete facing walls is changed to identify the effects of the facing wall stiffness.