• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.35-45
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• 2017

Gravel compaction pile (GCP) is widely used as it increases the bearing capacity of soft ground and reduces the consolidation settlement. Stress concentration ratio for design is dependent on the area replacement, surcharge pressure, depth and penetration rate. However, a range of stress concentration ratio obtained through field, laboratory experiments and numerical analysis is large. But since the main objective of the study is to evaluate the stress concentration ratio and settlement for both area replacement ratio and penetration rate through numerical analysis. Numerical analysis using the finite element program ABAQUS 6.12-4 has been performed for the composite ground with GCP. As a result, the stress concentration ratio at the points except for the point of top is in the range of 1.21-5.36, 1.19-5.45, 2.16-5.60 for 60%, 80% and 100% penetration, respectively. In general, as the penetration rate and area replacement ratio increases, the stress concentration ratio tends to increase.

• Journal of the Korean Geotechnical Society
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• v.32 no.9
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• pp.37-50
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• 2016

Gravel compaction pile (GCP) is widely used as it increases the bearing capacity of soft ground and reduces the consolidation settlement. Stress concentration ratio for GCP design is dependent on the area replacement, surcharge pressure and depth. However, a range of stress concentration ratio obtained through field, laboratory experiments and numerical analysis is large. Little study has been done on the stress concentration ratio for the mixing ratio of gravel and sand. The main objective of the study is to evaluate the stress concentration ratio for both area replacement ratio and mixing ratio through literature review and numerical analysis. Numerical analysis using the finite element program ABAQUS 6.12-4 has been performed for the composite ground with GCP. The excess pore water pressure and stress concentration ratio of composite ground have been analyzed for both the area replacement ratio and the mixing ratio. Based on the previous research results, a range of stress concentration ratio obtained from the field tests, laboratory tests, numerical analysis on the GCP studies is found to be 1.7-3.2, 2.0-7.5 and 2.0-6.5, respectively. Based on the numerical analysis results, as the area replacement ratio increases, the stress concentration ratio increases up to 30% and then decreases at 40%. Also, the stress concentration ratio tends to increase up to 70:30 and then to decrease after 60:40.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.163-170
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• 2006

Together with the trend of enhancement in domestic industrial development and economic progress due to import and export, the demand for construction of the roads, bridges, especially port facilities, and several coastal protection and ocean structures is increasing rapidly. MOMAF of Korean Government is driving construction of 9 new ports and renovation of the existing fishery ports. Among these structures most of bridge base, wharves, dolphins, quays, and jetties are being newly built of steel or concrete pile. As the base, supporting bulkheads, and piles are underwater after construction, it is difficult to figure out the status of structures and not enough to get maintenance and strengthen the structures. Every year, moreover, these works suck the government budget due to higher incomplete maintenance expense for protection from corrosions of structures and increased underwater construction period. For the purpose of cutting down the expense of government budget, it is necessary to extend the life cycle of the existing structures. Therefore, we developed a new method for maintenance of submerged structures near the waterline by allowing dry work environment with the floating caisson. The method shows easy to move around the working area and handle. It also showed not only a significant reduction maintenance expenses and time for anti-corrosion work but also better protection. This will be a milestone to reduce the maintenance and construction expenses for the shore and water structures.