Performance evaluation of open-cell caisson breakwater system using finite element method
Recently, coastal city and facilities had many damages by abnormally high waves with climate change. Especially, breakwater systems based on a caisson-type harm damages in Korea because they are located in the outside port. In order to reduce theses damages, new type breakwater systems using interlocking caisson are researched. Generally, caissons of breakwater system were constructed on crushed rock mound. They had a little space of 10–20 cm between each caisson. In this reason, they resist separately under external environmental ocean condition. A resistance mechanism of this method is friction force between caisson and crushed rock. Majority of failure is sliding failure, when it is exposed to more than design load. On the contrary, new type breakwater system as interlocking caissons resists effectively against abnormal wave because they are connected by specific joint method between each caisson. In this study, based on an open-cell caisson which is one of the interlocking concepts, we evaluated the performance of dynamic behavior for breakwater system using finite element analysis such as distribution subgrade reaction force, structural behavior of global system etc. According to analysis result, the open-cell caisson has good performance compare with general caisson type.
Dispersion Characteristics of Wave Forces on Interlocking Caisson Breakwaters by Cross Cables
Damage level of coastal structures has been scaled up according to increase of wave height and duration of the storm due to the abnormal global climate change. So, the design criteria for new breakwaters is being intensified and structural strengthening is also conducted for the existing breakwaters. Recently, interlocking concept has been much attention to enhance the structural stability of the conventional caisson structure designed individually to resist waves. The interlocking caisson breakwater may be survival even if unusual high wave occurs because the maximum wave force may be reduced by phase lags among the wave forces acting on each caisson. In this study, the dispersion characteristics of wave forces using interlocking system that connect the upper part of caisson with cable in the normal direction of breakwater was investigated. A simplified linear model was developed for computational efficiency, in which the foundation and connection cables were modelled as linear springs, and caisson structures were assumed to be rigid. From numerical experiments, it can be found that the higher wave forces are transmitted through the cable as the angle of incident wave is larger, and the larger the stiffness of the interlocking cable makes larger wave dispersion effect.
Role of the coronoid process in varus osteoarticular stability of the elbow.
The role of the coronoid process in varus osteoarticular stability of the elbow was investigated in 10 cadaveric elbows. Testing was performed at multiple flexion angles after incremental removal of the coronoid. At each flexion angle, removal of more than 50% of the coronoid produced a statistically significant decrease in the load resisting varus displacement compared with all lesser resection levels (P < .003). There was a trend for decreasing load after removal of 50% of the coronoid. The mean decrease in load across all flexion angles was 10.1%, 50.4%, and 75.4% after removal of 50%, 75%, and 100% of the coronoid, respectively. Resistance to varus displacement tended to decrease more as a percent of control at lower flexion angles than at higher flexion angles after removal of more than 50% of the coronoid. The coronoid process was found to be a key varus stabilizer in the elbow and may contribute more to elbow stability in extension than in flexion.