Evaluation and development of CPT-based design methods for the laterally loaded pile in sand

In this thesis the performance of five CPT-based p-y models by Novello (1999), Dyson & Randolph (2001), Li, et al. (2014) and Suryasentana & Lehane (2014;2016) is assessed. This is done in part by comparing the measured load-deflection response from a set of lab- and field tests that is representative for offshore monopile structures to...

Experimental and numerical investigation of the effect of vertical loading on the lateral behaviour of monopiles in sand

The influence of combined loading on the response of monopiles used to support offshore wind turbines (OWTs) is investigated in this paper. In current practice, resistance of monopiles to vertical and lateral loading is considered separately. As OWT size has increased, the slenderness ratio (pile length, L, normalised by diameter, D) has...

Impact of scour on lateral resistance of wind turbine monopiles: An experimental study

The majority of offshore wind structures are supported on large-diameter, rigid monopile foundations. These piles may be subjected to scour due to the waves and currents that causes a loss of soil support and consequently decreases the pile capacity and system stiffness. The results of numerical models suggest that the shape of the scour hole...

Influence of scour depth and type on p–y curves for monopiles in sand under monotonic lateral loading in a geotechnical centrifuge

The influence of scour on the lateral response of monopile foundations for offshore wind turbines is investigated in this paper. Application of lateral load-displacement (p-y) curves to predict the lateral pile behaviour is subject to uncertainty as many of the presently used design approaches have been derived for long, slender piles. These...

CPT-based method to determine the lateral capacity of monotonically loaded rigid piles in sand

Monopiles are commonly used as foundations for offshore wind turbine generators (WTGs). Due to the rapid growth of the offshore wind energy sector, there is increasing demand for WTGs of larger capacities which evidently leads to demand for monopiles with larger diameter. An industry standard approach for assessing pile lateral response is the p...

Dynamic Analysis of a Monopile Offshore Wind Support Structure Subjected to Earthquakes: A Comparative Study Between the Responses of an Elastic and an Inelastic Soil-Structure Interaction Model Through Incremental Dynamic Analysis

This thesis project has set out to investigate the response in fore-aft direction of a monopile wind foundation supporting an NREL 5MW turbine, offshore the coast of Taiwan, which is affected by weak to strong earthquake ground motion in combination with normal sea state conditions. The soil at the location of the monopile is layered, with sand...

Numerical & experimental investigation on the effect of scour formation and protection on the monopiles behavior

Offshore wind farms are rapidly developing in Western Europe as an alternative means of clean energy. The foundation of wind-turbines in the shallow water of the Northern Sea is almost exclusively (over 87%) performed by short rigid monopiles, as an efficient and relatively cheap solution. Scour formation, meaning the soil removal around the...

Investigation into a new CPT-based design method for large diameter monopiles in sand

The API RP 2GEO (2011) p-y method is an industry standard approach to predict the lateral pile behaviour of slender oil platform piles with length (L) over diameter (D) ratios > 10. However, offshore wind turbines are founded on large diameter monopiles with an L/D ratio < 8, which are rather rigid piles. There are concerns about the...

Laterally loaded piles in sloping ground

The subject of this master's thesis stems from a lack of design rules in the current regulations for dolphins located in sloping ground. Dolphins are very common objects in Dutch waterways, of which a large part are located in sloping ground. The lack of design rules causes difficulties between clients and contractors, possible unfavourable...

Flexural buckling of micro piles - Buigingsknik van ankerpalen

This thesis focuses on the stability of slender micro piles with a diameter of 100-400mm in soft soils when used in compressive situations. In the western part of the Netherlands and many other deltaic areas weak clay and peat deposits overlay stiffer sand layers. In these geological conditions flexural buckling may cause a considerable design...

A comparison of a 3 dimensional probabilistic method of berthing structure design and the traditional method of a berthing structure design

Finite element method (FEM) is increasingly applied as a first choice tool for designing structures. The same trend is seen in probabilistic designing. Consequently, the application of the combination of these two methods is discussed in this paper.In this study the presence of potential overcapacity in a structure has been studied. As an...

Differences between a 3 dimensional probabilistic method of berthing structure design and the traditional method of a berthing structure design

Jetties are designed by the guidance of the deterministic standards. These standards are based on the standardized values of safety factors (semi-probabilistic) and use the load and the capacity of every element as a standard value. The interaction of every separate element as a part of a whole is not taken in to account. The use of...