• Journal of Ocean Engineering and Technology
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• v.15 no.3
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• pp.114-119
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• 2001

Goda formula (Goda, 1973) has been used in the determination of wave pressures acting on a large size caisson such as the pier of the cable stayed bridge at sea. Goda formula, however, is to evaluate the wave pressures acting the infinite vertical caisson of composite breakwater so that it can`t be applied to a large caisson with finite width and length because of diffraction effects. In the present study, three dimensional nonlinear frequence domain method based on perturbation method and boundary integral method is applied to the computation of the linear and nonlinear wave pressures acting on the front of a large size caisson under the variation of its width and length, and angle of incident wave. The numerical results are compared to Goda\`s ones, and then the characteristics of wave pressure distributions acting on a large size caisson are discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.400-403
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• 2004

In conventional methods, the availability of floating crane has determined the size of a concrete caisson. However, this paper introduces a new method for larger caisson production that make it possible to complete caisson fabrication and launch out without use of floating crane. The new method carries out multi-step fabrication of caisson and horizontal transfer of caisson on a single casting bed which consists of collapsible soffit form, trough, aero go watercaster system or low frictional PTFE added jacking system, half-submergible floating dock. To make the new method successfully launched, the static and dynamic analysis is carried out to obtain the stability of caisson launching and experimental research is conducted in evaluating friction occurred between PTFE pad and steel track. Lastly, the comparison of the new method and the conventional method are detailed. With significant benefits in construction costs reduction and construction time reduction, this new method in this paper would be recommended for extensive application in large port and harbor construction projects.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.227-233
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• 2009

This experimental study has been carried out to investigate the reduction in side friction of open caisson using air-jet method. For this study, the large size caisson having air-pockets was used. This caisson was used as substructure of bridge. By using air-jet method, settlement time was decreased and even settlement was reached to the depth which conventional methods could not be. We found that the side resistance decreases to less then half the expected value. In addition to these merits, the air-jet method can result in self-weight settlement without applying additional load. Also the open caisson damage caused by blasting can be prevented with this method.

• Journal of the Korean Geotechnical Society
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• v.20 no.4
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• pp.15-27
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• 2004

In this study, skin friction evaluation methods developed f3r deep foundation system were investigated and a method that can properly evaluate the skin friction of large size pneumatic caisson was proposed. Especially, based on Hong Won-Pyo's method, new technique (Kn parameter method) was suggested for estimation of the skin friction. The $\lambda$ method used widely to pile foundation was also investigated fur the applicability of estimation of the skin friction of large size pneumatic caisson. To do this, the data measured from the pneumatic caissons installed as a substructure of main tower in the suspension bridge part of Youngjong Grand Bridge were utilized. The data show that the skin friction is proportional to the rate of sinking, and the skin friction distribution with depth is similar to parabolic type rather straight line, which is a type generally observed in pile foundation. The skin frictions predicted by the Kn and $\lambda$ methods were plotted with the measured data for comparisons. It is cleary shown that the skin frictions estimated by the proposed Kn parameter method are well matched with the measured data. That is, for the large size pneumatic caisson having wide base, the new technique developed from Hong Won-Pyo's method is more suitable for estimation of the skin friction rather than the $\lambda$ method.

• Proceedings of the Korean Geotechical Society Conference
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• 1992.03a
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• pp.1-12
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• 1992

In recent years, active developments have taken place in Southeast Asia in various aspects of deep foundations. Some of these developments are reviewed in this Paper. These include techniques of behaviourial analysis such as Chin's Plot and Balasubramaniam's Pull-out Test. Also included are recent advances in small size piles, large bored piles and caisson foundations. The performance of and the experience gained in some of these foundations are highlighted.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.11a
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• pp.110-121
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• 2001

The interest in suction piles by the oil industry was risen in the middle of 1980's. Recently, suction piles have been applied increasingly in offshore engineering due to its low cost, simplicity, efficiency, and reliability. Suction piles have normally been used as anchors of floating structures and foundations of marine structures in deep-water locations. Suction piles have several technical advantages over conventional piles and anchors; fast and easy installation at any depth of water, extremely large resistance due to its huge size, and easy retrieval by applying a positive suction pressure inside the pile, etc. Daewoo E&C Co., Ltd. has conducted a series of field suction pile installation and loading tests inside the Okpo harbor located in Geojedo and the Onsan harbor in Ulsan, Korea, during the summer of 2001, which may provide additional validation of the analytical solutions previously developed by the US Naval Facilities Engineering Service Center. This is a brief description of the general mechanisms of suction pile installation and loading capacity based on the study conducted by the US Navy and Daewoo E&C Co., Ltd.