• Journal of the Korean GEO-environmental Society
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• v.5 no.1
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• pp.65-73
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• 2004

The analysis of corrugated steel pipes is depending on a second dimension frame analysis or compressed ring model. This is the analysis not to consider the behavior of soil-structure interaction. The behavior of load resistance system is varied according to the depth of cover and the spacing of corrugated steel pipes structure. Therefore, the behavior characteristic of corrugated steel pipes was confirmed through finite element analysis to consider the activity of soil-structure interaction. If soil cover is filled up to the more of optimal depth, behavior of corrugated steel pipes are similar to those of ductile steel pipes according to the earth pressure distribution and effects of traffic loads are decreased. But, If soil cover is filled up to the less of optimal depth, corrugated steel pipes can't behave completely as ductile steel pipes because the passive earth pressure acting on side of corrugated steel pipes is decreased according to the decrement of vertical earth pressure, and the traffic loads influence on the section forces is increased, so that the traffic loads dominated the behavior of corrugated steel pipes.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.06a
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• pp.77-89
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• 2002

To analyze a bearing capacity for pile groups, a number of model tests have been done and theoretical methods studied. In the case of design of group pile bearing capacity is calculated with only pile capacity. But uncertainty of bearing capacity and behavior of foundation cap(raft) leads to conservative design ignoring bearing effects of foundation cap. In the case of considering bearing capacity of foundation cap, the simple sum of bearing capacity of foundation cap and pile groups cannot be the bearing capacity of total foundation system. Since cap-pile-soil interaction affects the behavior of pile groups. Thus, understanding cap-pile-soil interaction is very important in optimal design. In this paper, the piled raft behavior is studied through model tests of 2$\times$2, 2$\times$3, 3$\times$3 pile group. Changes of behavior of pile group foundation by touching effects of foundation cap with soil are studied. Also changes of spacing between piles. Foundation cap is made of rigid steel plate and piles are made steel pipes. From this model tests, the changes of behavior changes of pile groups by touching effects of foundation cap with soil are studied.

• Earthquakes and Structures
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• v.26 no.2
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• pp.149-162
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• 2024

Aiming at the current research on the dynamic response analysis of the vehicle-bridge system under earthquake, which fails to comprehensively consider the impact of seismic wave incidence angles, terrain effects and soil-structure dynamic interaction on the bridge structure, this paper proposes a multi-point excitation input method that can consider the oblique incidence seismic P Waves based on the viscous-spring artificial boundary theory, and verifies the accuracy and feasibility of the input method. An overall numerical model of vehicle-bridge-soil foundation system in valley terrain during oblique incidence of seismic P-wave is established, and the effects of seismic wave incidence characteristics, terrain effects, soil-structure dynamic interactions, and vehicle speeds on the dynamic response of the bridge are analyzed. The research results indicate that with an increase in P wave incident angle, the vertical dynamic response of the bridge structure decreased while the horizontal dynamic response increased significantly. Traditional design methods which neglect multi-point excitation would lead to an unsafe structure. The dynamic response of the bridge structure significantly increases at the ridge while weakening at the valley. The dynamic response of bridge structures under earthquake action does not always increase with increasing train speed, but reaches a maximum value at a certain speed. Ignoring soil-structure dynamic interaction would reduce the vertical dynamic response of the bridge piers. The research results can provide a theoretical basis for the seismic design of vehicle-bridge systems in complex mountainous terrain under earthquake excitation.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.2
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• pp.43-49
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• 1986

Field experiment was conducted to investigate the effect of vinyl mulch on phosphate availability of soil and fertilizer in 1982. Growth of tobacco was more vigorous at each level of phosphate treatment in vinyl mulched than in bare soil. There was significant culture x Phosphorus treatment interaction for the yields of cured tobacco leaves. These results indicated that vinyl mulch was effective to improve phosphate availability of soil and fertilizer. Increase in soil temperature and maintenance of bulk density suitable for Phosphorus diffusion by vinyl mulch were likely to Play major roles on Phosphate availability, but other unknown factors appeared to be involved.

• Structural Engineering and Mechanics
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• v.40 no.6
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• pp.763-782
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• 2011

Results from nonlinear time-history analyses of wall-frame structural models indicate that the condition of vulnerable foundations -for which uplifting and reaching the bearing capacity of the supporting soil can occur before yielding at the base of the shear walls- may not be necessarily detrimental to the drift response of buildings under strong ground motions. Analyses also show that a soil-foundation system can inherently have deformation capacity well in excess of the demand and thus act as a source of energy dissipation that protects the structural integrity of the shear walls.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.83-93
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• 2006

In heavily industrialized areas, soil sites are contaminated with high concentrations of heavy metals. These pollutants are highly accumulated to the human body through the food web and cause serious diseases. To remove heavy metals from the soil, a potential strategy is the environmental friendly and cost effective phytoremediation. For the enhancement of remediation efficiency, the symbiotic interaction between the plant and plant growth-promoting rhizobacteria (PGPR) has been attended. In this review, the interaction of the plant and PGPR in the heavy metal-contaminated soil has been reviewed. The physicochemical and biological characteristics of the rhlzosphere can influence directly or indirectly on the biomass, activity and population structure of the rhizobacteria. The root exudates are offered to the soil microbes as useful carbon sources and growth factors, so the growth and metabolism of rhizobacteria can be promoted. PGPR have many roles to lower the level of growth-inhibiting stress ethylene within the plant, and also to provide iron and phosphorus from the soil to plant, and to produce phytohormone such as indole acetic acid. The plant with PGPR can grow better in the heavy metal contaminated soil. Therefore higher efficiency of the phytoremediation will be expected by the application of the PGPR.

• Journal of the Korean GEO-environmental Society
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• v.24 no.9
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• pp.15-24
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• 2023

The behavior of buried pipes is directly influenced by the nonlinearity and complex characteristics of the surrounding soil. However, the simplified beam-spring model, which ignores the nonlinearity and complex behavior of soil, is commonly used in practice. In response, several studies have employed continuum analysis methods to account for the nonlinear and complex behavior of the soil. This paper presents various numerical continuum analysis techniques and verifies their comparison with full-scale tests. The study found that reaction force results close to the full-scale test could be obtained by applying contact surface characteristics that take into account the interaction between the ground and the buried pipe. In the case of sharing pipe and soil node method and ignoring the interaction between pipe and soil, excessive reaction force was derived, and the failure shapes were different. In addition, this study applied the dynamic explicit analysis method, ALE method, and CEL method. It was confirmed that the displacement-reaction relationship and failure shape are similar to those of the static analysis.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1073-1087
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• 1993

Many investigations have been carried out concerning tillage tool performance, including energy requirement . Since the performance of tillage could also be evaluated through the change of soil , then it is necessary to investigate the soil cutting process and the pattern of soil failure. This study was conducted using indoor soil bin, STILT (Soil Tillage Tool Interaction) system. The result shows that the soil bin experiments could provide the clear understandings about phenomena of soil failure. The movement of sil , the successive failures was clearly visualized. The relations between the horizontal and vertical forces to the linear motion blade, the shear force on the shear plane which devides soil layer into several segments were indicated by the fluctuation/vibration of the recorded resistance and forces. The results show that the horizontal force(Fx) and vertical force (Fz) develope their frequencies as the change of velocity of blade (10, 20, 40 mm/sec) for each cutting angle (35, 45, 60 degrees). Resultant force of Fx and Fz are much influenced by the cutting angle.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.397-408
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• 2004

The aim of this paper is to study the interaction between adjacent buildings with different foundation levels under earthquake loading conditions. Buildings and soil are represented by two different models. In the first case, the building itself is modeled with standard frame elements, whereas the soil behavior is simulated by a special grid model, In the second case, the building and soil are represented by plane stress or plane strain elements. The modulus of elasticity of the ground as well as the varying relations of inertia have a strong influence on the section forces within the buildings. The interaction between the two buildings is demonstrated and discussed via numerical examples using the proposed method.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.109-116
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• 2002

Since experimental evaluation of underground RC structures considering interaction with surrounding soil medium is quite difficult to be simulated, the evaluation for the underground RC structures using an analytical method can be applied very usefully. For underground structures interacted with surrounding soils, it is important to consider path-dependent RC constitutive model, soil constitutive model, and interface model between structure and soil, simultaneously. In this paper, an elastoplastic interface model which consider thickness of interface is proposed and applied for the analysis considering the interaction. Failure mechanism of underground RC box of two story and two box subway station under seismic action is obtained and the effects of ductility of intermediate column to entire underground RC system are investigated through analysis.