• Journal of the Korean GEO-environmental Society
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• v.24 no.8
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• pp.5-11
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• 2023

Due to frequent occurrences of concentrated heavy rainfall caused by abnormal climate conditions in recent years, collapses of steep slopes have been occurring frequently due to surface erosion and increased pore water pressure. Various methods are being applied to prevent slope collapses, such as increasing the resistance to movement and reducing pore water pressure. Research on these methods has been consistently conducted as they provide an efficient response to slope collapses by satisfying both the conditions of resistance to movement and pore water pressure simultaneously. Therefore, in this study, we propose an upward slope reinforcement method by burying drainage materials with an upward slope inclination, instead of the conventional horizontal application. This approach aims to satisfy both slope reinforcement and drainage functions effectively, offering a comprehensive solution for slope stabilization. Furthermore, to determine the optimal burial angle that exhibits the most effective reinforcement and drainage effects of the proposed method, we investigated the reinforcement and drainage effects under conditions where the horizontal drainage materials were set at angles ranging from 0° to 60° in increments of 10° on a representative cross-section. Additionally, indoor model experiments were conducted under the conditions of 40°, which showed the most outstanding drainage effect, and 20°, which exhibited the highest safety factor, to validate the numerical analysis results. The results showed that the burial angle of 40° exhibits a relatively higher drainage effect as with the numerical analysis results, while the angle of 20° results in inadequate drainage and observed slope collapse.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.1
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• pp.233-239
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• 2002

Reinforced concrete deck slabs are directly affected by traffic loads and they are also susceptible to weather-related problems, such as cracking, reinforcement corrosion, spatting, scaling, delamination, leakage, efflorescence and so on. Some of these defects are caused by water which seeps through pavements and trapped between pavements and deck slabs. For durability of reinforced concrete deck slabs and pavements, it is very important to protect deck slabs and drain the trapped water out. To develop the trapped water drainage system, the following studies have been performed in Korea Highway Cooperation: related researches a re reviewed; for six bridges, deck slabs are thoroughly investigated; new system to effectively drain the trapped water out is proposed; the proposed system is installed and evaluated. The proposed system is proved to be effective to drain the trapped water out and is expected to increase the durability of reinforced concrete deck slabs.

• Advances in concrete construction
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• v.7 no.3
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• pp.191-201
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• 2019

Bamboo concrete bond behaviour is investigated through pullout test in this work. The bamboo strip to be used as reinforcement inside concrete is first treated with chemical adhesive to make the bamboo surface impermeable. Various surface coatings are explored to understand their water repellant properties. The chemical action at the bamboo concrete interface is studied through different chemical coatings, sand blasting, and steel wire wrapping treatment. Whereas mechanical action at the bamboo concrete interface is studied by developing mechanical interlock. The result of pullout tests revealed a unique combination of surface treatment and grooved bamboo profile. This combination of surface treatment and a grooved bamboo profile together enhances the strength of bond. Performance of a newly developed grooved bamboo strip is verified against equivalent plain rectangular bamboo strip. The test results show that the proposed grooved bamboo reinforcement, when treated, shows highest bond strength compared to treated plain, untreated plain and untreated grooved bamboo reinforcement. Also, it is observed that bond strength is majorly influenced by the type of surface treatment, size and spacing of groove. The changes in bamboo-concrete bond behavior are observed during the experimentation.

• Journal of the Society of Disaster Information
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• v.9 no.3
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• pp.315-323
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• 2013

Recently, FRB is being used more as reinforcement of RC beam thanks to its material advantages in construction industry. The external attachment reinforcement of FRP is a construction method with advantages such as high strength, stiffness, excellent durability and construction practicability, despite of its weight. However, the reinforcement has a disadvantage to cause damage on permanent structure as its structure is water-tight by low water permeability reinforcement, preventing water from draining outside. The study attempted flexural failure test for GP of which material properties are equally same as the existing FRP and that with permeability, shows good binding with the concrete structure, durable performance and durability, comparably analyzing the improvement of durability and ductility according to changes of fiber contents of composite strip.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.348-353
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• 1996

This study addresses the evaluation of the durability of reinforced concrete marine structures subjected to fatigue loading. The laboratory investigation was carried out on full and half size reinforced concrete specimens with three different water cement ratios (0.3, 0.4, and 0.56), static and fatigue loading conditions, and epoxy-coated and regular black steel reinforcements. The marine tidal zone was simulated by alternate filling and draining of the tank (wet and dry cycled), and a galvanostatic corrosion technique to accelerate corrosion of reinforcement was used. Half-cell potentials and changes of crack width were measured periodically during the exposure and followed by ultimate strength testing. The significant findings include adverse effect of fatigue loading, existence of an explicit size effect, poor performance of epoxy coated steel, and negative effect of increasing water/cement ratio.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.930-937
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• 2008

From the result of precise field investigation and stability analysis for the cut slope, following results were acquired. 1. The cause of the collapse of cut slope came from circle sliding collapse by fault zone which remained inner weathering zone. 2. The existing destructed soil and rock can be removed by reinforcement. And to prevent the additional destruction, it is judged that applying the method after relaxing the slope would be reasonable. 3. To make cut slope stable, soft rock layer should be done cutting 1:1.5 and 1:2.0 ~ 1:2.5 for weathered rock and soil layer. 4. Heavy water leakage section should be applied horizontal drain method so that water pressure should not act to the cut slope.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.E
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• pp.47-54
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• 1995

Irrigation water has been mainly used for paddy rice. Irrigated paddy land tends to be recently converted to land for green house, farm house, and rural-industrial complex. Consequently, demand of water for crops, domestic & industrial, rural recreations, small-scaled hydropower, livestocks, and environment in the rural area, so called rural water, is rapidly increasing. In order to supply rural water, water in the existing irrigation reservoir could be enlarged by repairment of irrigation canal and reinforcement of irrigation reservoir, and be saved by the operation rule curve, utilization of dead water, and balanced storage management.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.3
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• pp.8-13
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• 2015

This study investigates the application of a synthetic resine based net-hose system to sustain vegetated embankment slope reinforcement. The net-hose system is designated to improve water supply to the vegetation that can suffer the lack of water in case of extreme drying condition or rock slope where water supply is relatively insufficient to ensure the growth of vegetation. A series of laboratory tests were conducted to check the structural adequacy and effectiveness of net-hose system. The results indicated that the model slope equipped with net-hose system seemed to provide better water supply resulting in more vegetated areas and higher matric suction due to active water uptake capacity, which might be contributed to greater shear strength of slope surface. A limited numerical analysis was conducted to verify the effect of water uptake on vegetated root system that generally yields better slope stability.

• KCID journal
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• v.10 no.1
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• pp.132-138
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• 2003

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.338-350
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• 2010

As existing materials for ground reinforcement, chemical grout material using cementitous materials and waterglass was used. But many problems in terms of ground reinforcement effects were implicated. In this study, for development and applicability verification of new materials, viscosity, fluidity, permeability, Self-Leveling, keeping of drilled hole, antiwashout underwater, resistance of water (groundwater dilution and minimize material eluting) and the early strength and long-term strength characteristics of developed materials was confirmed, and material standards, and establishing construction standards for the various model tests were conducted. As a result, high viscosity, flowability, permeability and keeping of drilled hole characteristics are excellent, in addition to the early strength properties, dilution does nat occur to groundwater, including groundwater is available for dealing with environmental issues. Application of basic and reinforcement method by Filler function in addition to structure can also or development of a new concept can be expected. In addition, middle and large-diameter drilled shaft, micropile, ground anchors, soil-nailing, steel pipes multi-grouting reinforcement for cement injection process could be used enough to even be considered.