STUDY ON A NEW DESIGHN METHOD FOR UPLIFT PRESSURE ACTING ON A PIER AT OBLIQUE INCIDENCE WAVES

Abstract

 According to the 2018 edition of the technical standards and commentaries for port and harbor facilities in Japan, the uplift pressure acting on a pier should be designed at a pressure equivalent to four times the wave height (4_ρgH), which is considered to be the upper limit for a perpendicular-entry case. However, this value is so large that it is difficult to design it . In the case of an actual pier, the wave incidence is often oblique, and Watabe et al. (2003) confirmed that the uplift pressure acting on the pier is smaller than that of a pier with waves entering perpendicularly. However, there have been few studies on the uplift pressure acting on piers with oblique incident waves, and design methods have not been established. However, there have been few studies on the uplift pressure acting on piers with oblique incident waves, and design methods have not been established. In this study, hydraulic model experiments were conducted at several angles of incidence wavs, including direct incidence waves, and the results were analyzed using the new method proposed in this study. As a result, it is clarified that the average uplift pressure over the entire pier decreases to 1/6 to 1/10 of that at oblique incidence angles, depending on the angle of incidence.