Osoon Kwon

Field Installation Tests of Monopod Suction Pile and Tripod Suction Buckets

Small-scale field tests on a monopod suction pile with and without the detachable penetration apparatus (DPA) and tripod suction buckets have been performed. One of the objectives of the field tests was to identify the capability of the DPA at small-scale and to obtain useful information for planned future full-scale field tests. The DPA which has been developed to control and increase the accuracy of the verticality of monopod suction piles during installation. In addition, it can also contribute to increase the penetration force under certain conditions. Included in this paper are the details of the small-scale field tests, including the site conditions, suction pile details, DPA details, installation, instrumentation equipment, and test results. Results indicate that the tripod suction buckets have a significant advantage over the monopod suction pile for verticality control and that the newly developed DPA is fully capable of enhancing the verticality control of the monopod suction pile during installation.Copyright

FLOW-3D Analysis on Scouring around Offshore Wind Foundation

In order to evaluate the local scour around offsshore wind foundation, mono pile and jacket foundation were simulated by using FLOW-3D. Numerical analysis results show that local increases of velocity around mono pile and jacket foundation was developed but velocity decreases in backward of pile and leg due to the wake vortex was observed. Local increases of velocity around foundation and scouring of jacket is more significant than that of mono pile, since jacket is the complex structure and has the interference effect with legs. Therefore, in order to evaluate the scour and design the scour protection method, the form and shape of substructures of offshore wind should be considered.

Pullout Behavior of Multiple Suction Pile Anchors with Various Sections Using Numerical Analysis

As the size of offshore structures has been increasing, the interest for foundation systems with large capacity is also rising. Along with this trend, studies are in progress on suction piles (widely used as mooring anchor systems) which can develop large capacity. In this paper, the concept of multiple suction pile anchors - which are composed of several suction piles connected in parallel - is introduced. Two types of multiple suction pile anchors are presented. In one type, two single-suction piles are connected. The other type is composed of three single-suction piles connected in parallel. The pullout behavior of the single-suction pile anchor and the two types of multiple suction pile anchors are investigated using numerical analysis. Numerical simulations using Abaqus software are performed and the three-dimensional model is deployed to duplicate the body shape of suction pile anchors. The load and displacement of the suction pile anchors are computed under continuous horizontal loading, and the pullout capacity of each type of suction pile anchors is evaluated.