Pokusna procjena svojstava materijala i nosača za fleksibilne privezne stupove

Milan Batista,Faculty Of Maritime Studies And Transport Portorož, Slovenia ,Aleksander Grm

doi:10.17818/nm/2017/2.2

Milan Batista, Faculty Of Maritime Studies And Transport Portorož, Slovenia + Show 1 more

Open Access

https://doi.org/10.17818/nm/2017/2.2

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Journal: Naše more	Publication Date: Jun 1, 2017
License type: cc-by

Abstract

Present work describes the inverse problem for identification of material and support type properties of flexible dolphin structure. Most liquid bulk terminals are equipped with a jetty as berthing facility. The ship mostly berths to dedicated breasting dolphin structures, which can be single-pile flexible/rigid dolphins or multi-pile flexible/rigid dolphins. This work considers dolphin motion as mass-spring damped system where cantilever approximation mimics dolphin pile. Few measurements have been made for the dolphin structure, which is approximately 30 m long, 15 m immersed in the bottom and placed about 2-3 m above the sea level. The elastic material properties and pile support were identified via inverse method combined with displacement measurements of dolphin head.

Highlights

In this paper an inverse procedure to estimate the stiffness and support of dolphin structure based on the beam theory will be presented
Let us assume that the cantilever models the flexible dolphin structure and its deflection is x = ∆ = F L3 κα where κ = E I is cantilever bending stiffness (E-elastic modulus, I-beam cross section moment of inertia), F is the force applied at the end of a cantilever, L is its length and α is a parameter that depends on a type of dolphin mount on the seabed
Fitting model reveals that the oscillations are slowly damped and the damped frequency of structure ωd =ω0

Summary

Present work describes the inverse problem for identification of material and support type properties of flexible dolphin structure. Most liquid bulk terminals are equipped with a jetty as berthing facility. The ship mostly berths to dedicated breasting dolphin structures, which can be single-pile flexible/rigid dolphins or multi-pile flexible/rigid dolphins. This work considers dolphin motion as massspring damped system where cantilever approximation mimics dolphin pile. Few measurements have been made for the dolphin structure, which is approximately 30 m long, 15 m immersed in the bottom and placed about 2-3 m above the sea level. The elastic material properties and pile support were identified via inverse method combined with displacement measurements of dolphin head.

KEY WORDS cantilever beam flexible dolphin pile material properties support type

Mid Value

DISCUSSION