Abstract
Within the context of offshore structures forrenewable energy and oil & gas, anchoring systems
play an important role in the stability of floating
devices. Plate anchors can be used to moor floating
Entry Details
structures both in taut-leg and catenary
configurations. So far, no well-established anchor
design criterium capable of predicting the ‘whole-life’
anchor behaviour has been developed. In parallel to
that, macro-element models are a time-effective
approach that has been used for several geotechnical
applications, though limited work has been done on
macro-element for anchors. Furthermore, few macroelement models have considered the effect of pore
pressure generation and dissipation, as most of them
have been developed for either drained or undrained
cases. In that context, this thesis presents a macroelement framework that combines an advanced
macro-element model for anchors with a
representative soil element that captures the
behaviour of the whole soil mass around the anchor.
The representative soil element tracks the effects of
changes of effective stress on the soil strength, which
in turn governs the anchor capacity in the macroelement model. The two modelling components are
linked through a mobilised capacity compatibility
condition. The modelling framework is challenged to
simulate the behaviour of plate anchors in cohesive
soils subjected to long-term cyclic and maintained
loading and compared with centrifuge test results
published in the literature. In addition, the model is
assessed by comparison with centrifuge data in plate
anchors subjected to different loading rates in noncohesive soils. It is shown that the model is able to
predict the evolution of anchor capacity under
different loading conditions, provided that calibration
of model parameters with a limited number of
centrifuge tests is carried out.
Date of Award | 2 Dec 2021 |
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Original language | English |
Awarding Institution |
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Supervisor | Andrea Diambra (Supervisor) & Dimitris K Karamitros (Supervisor) |