This study evaluates the serviceability of floating structures designed for marine cities by incorporating wave-dissipating modules. Small-scale model tests in a 2D wave flume were conducted to compare with and without these modules under different conditions (1-year 100-year return period waves). The results showed that significantly reduced vertical acceleration, reductions approximately 44~45% levels 1-year waves 54~57% waves. When topside building was included, similarly pronounced,...

This study investigated the effects of construction sequence and thrust force from hydraulic jacks on stress distribution tunnel lining by analyzing field data measured at a real Tunnel Boring Machine (TBM) site. A three-dimensional Finite Element (FE) model that incorporated major design components TBM lining, such as face pressure, shield, grout, jack, well simulation step-by-step procedure was also proposed. Specifically, ring joints between linings were modeled using anisotropic solid...

This paper presents the results of wave force tests conducted on three types offshore support structures considering eight waves and sea levels to investigate corresponding forces. As a result this study, it is found that occurrence shoaling in shallow water induces significant increase force. Most test models at undergo nonlinear with higher height increasing. In addition, larger diameter structure within range diffraction effect is, due suppressed. Under an irregular water, long-period...

In this paper, for the case of “service life extension” with same capacity wind turbines, a structural safety evaluation was carried out to determine whether extend service aged foundation. As result study, it found that foundation satisfies material strength, ultimate fatigue life, and serviceability up present. Although in-service period has been over 16 years, shown properties concrete have exceeded design no significant deterioration occurred. Also, could be evaluated more realistically...

Park, M.-S.; Jeong, Y.-J., and Kim, J., 2018. Experimental test of 3kW cylindrical wave energy system with horizontal rotation. In: Shim, J.-S.; Chun, I., Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic Korea). Journal Research, Special Issue No. 85, pp. 1311–1315 Coconut Creek (Florida), ISSN 0749-0208.Since potential has been recognized for long mostly associated a nondestructive renewable energy, gained attention many countries to find...

A monopile is the most conventional structure foundation for offshore wind turbines (OWTs) in world. However, Korean industry has mostly been using jacket type of foundation. The main reason current situation Korea that marine soil consists weak layers sand and clay. Thus, depth to be deep enough satisfy intended serviceability design requirement rotation limit at seabed; a concept alone might insufficient conditions, or otherwise could very expensive, e.g., resulting rock socket...

In this study, in order to investigate wave force and wave-induced overturning moment according the support structure types sea levels, tests were carried out for three offshore structures of Monopile, GBS, Hybrid under levels HSWL, MSL, LSWL. As results it was found that, as height increased at shallow water (LSWL), significantly because nonlinearity, named shoaling. Also, structural member size became larger, nonlinearity effects on (LSWL) reduced diffraction effect large-sized member....

In this study, hydro-structural behavior of three types marine circular cofferdam system single steel-plate, corrugated and double steel-plate was investigated analytically. As a result the it found that type vulnerable to cross-section deformation, deformed in axial direction, local respectively. Also, indicated lower total shear force than plane since waveform caused diffraction effect on wave action. Based behaviors, advanced large will be proposed so as secure structural safety under condition.

본 논문은 모노파일 풍력 지지구조물에 대한 공진 안전성 평가에서 여러 말뚝-구조물 상호작용(PSI) 모델을 사용하여 고유진동수를 비교하였다. PSI 재현을 위한 유한요소모델은 기저 스프링 모델, 분산 3차원 고체-쉘 사용하였다. 모델이 고유주파수에 미치는 영향을 분석하기 위해 스프링과 모델 적용을 강성행렬 산정법과 Winkler 보 각각 논문에 나타내고 이들 모델로부터 도출된 서로 다른 기하 및 지반조건을 갖는 모노파일의 조사하였다. 해석결과는 또한 모델의 고유진동수와도 비교되었다. 소구경 모노파일이 견고한 지반 암반에 관입된 경우 각 해석모델로부터 얻어진 고유진동수의 차이가 거의 없음을 보여준다. 반면 연약 지반에 설치된 대구경 모노파일에 대해 모델은 과대평가할 수 있다. 따라서 고유진동수 평가 시 구조물 규모와 조건을 고려해 적합한 PSI모델이 적용되어야 한다.

본 연구는 유한요소 해석모델을 이용해 아치 형상을 갖는 석션 상판의 거동을 분석하였다. 평판형 및 아치형 기본적인 구조성능에 대해 비교함으로써 이점을 설명하였다. 또한 기하 보강재 배치 변화에 따른 거동 변화를 비교하여 각 인자가 응력 변형에 미치는 영향을 조사하였다. 추가로 상판 가장자리의 경계조건 수치적으로 분석함으로써, 배치와 가물막이 벽체와의 상호거동 규명하고 이를 통해 보강형 구조설계의 기본 개념을 도출하였다. 상판과 달리 환형 보강재가 구조 확연히 개선시킬 수 있음을 확인하였으며, 방사 보강재의 역할은 구속상태에 의존적이었다.

Abstract This study introduces a large offshore cofferdam installed by suction, unlike conventional ones such as sheet-pile type, and proposes an effective suction cap for the cofferdam. In structural design view of cofferdam, there are several critical issues due to its size. conducted analyses stiffened caps using fully nonlinear finite element models, analyzed changes in behaviors stiffener arrangements provide insights. For diameter thickness (circular plate only) 20m 0.07m,...