Kenneth Gavin

Delft University of Technology | TU · Department of Geoscience and Engineering

Fuelled by technological innovations and the growing commitment of countries to reduce their carbon footprint, offshore wind has steadily been gaining ground on non-sustainable sources of energy. According to the International Energy Agency (IEA) [2], it is foreseen that wind will be the principal source of energy in Europe by 2027. However, in an...

This paper describes axial load tests on three full-scale driven precast piles in the Netherlands. The piles were founded in dense to very dense river-deposited sands, a soil that is widespread across the Dutch North Sea sector. The deposit is characterised by cone penetration test (CPT) tip resistances of up to 90 MPa and offers a detailed insight...

This paper presents data from an initial development stage of an ‘umbrella anchor’ concept. The anchor can be pushed into sand deposit in a folded arrangement to reduce installation loads. When a pull-out load is applied to the mooring line, the anchor deploys to create a large embedded plate anchor. Physical modelling was carried out in saturated...

Dykes provide protection from the risk of flooding to approximately 60% of the Netherlands, by area. Unfortunately, most of the country's major cities lie within this zone, placing a large proportion of the population at risk should these flood defences fail. In total the Netherlands have over 3800 km of primary flood defences protecting the coast...

The paper proposes a solution for a Building Information Modeling (BIM)-enabled Infrastructure Asset Management System (AMS) for road owners. The approach provides asset managers with a strategy for the dynamic use of Information Containers for Linked Document Delivery (ICDDs), considering the requirements of stakeholders across domains in the oper...

Large-diameter monopiles are widely used as the foundation to support offshore wind turbines (OWTs) in shallow coastal waters. The benefits of small-to-medium diameter tapered piles have been reported in the past. The potential use of large-diameter tapered monopiles installed by impact driving to support OWTs is thus presented, and then comparativ...

Stresses generated from pile installation are a critical component in understanding pile behaviour. These are known as residual stresses and in Delft, the Netherlands, the response of three driven precast piles founded in sand was measured using distributed fibre optic sensing as part of a series of full-scale static load tests. The instrumentation...

A joint academia-industry project, the Pile Soil Analysis (PISA) project, resulted in an empir ical method for assessing the monotonic lateral loading response of large diameter monopiles. The method predicts four soil reactions, namely the distributed load and the distributed moment along the pile shaft, the pile base shear and the pile base momen...

Flooding is a significant threat to human-life, ecosystems, cultural heritage and society in general. A risk-based safety approach is necessary to support decision making and prioritize intervention measures, either during the response or during the prevention stage. As a consequence of flooding, transport infrastructure and flood protection system...

The intensity and frequency of flood events is increasing due to climate change impact and accompanying precipitation extremes. However, the impact of a given flood event depends critically on the resilience of the flood defence system, primarily a network of earth embankments and riverbanks. The paper presents the efforts conducted within the ongo...

Large areas of the Netherlands are dominated by deep, soft soil deposits, posing a challenge to engineers with respect to the design of axially loaded foundations. The design of these foundations is primarily based on methods which use cone penetration test (CPT) parameters, such as that outlined in the Dutch national standard NEN 9997-1. A recent...

To identify the unknown values of the parameters of Burger’s constitutive law, commonly used for the evaluation of the creep behavior of the soft soils, this paper demonstrates a procedure relying on the data obtained from multiple sensors, where each sensor is used to its best advantage. The geophysical, geotechnical, and unmanned aerial vehicle d...

The scour protection layers are usually installed around the monopiles to prevent the formation of scour hole. While extensive studies have been performed on the effectiveness of scour protection layer as mitigation measure, no study to date has been found to quantify the influence of scour protection layer on the lateral response of monopiles. In...

Weather phenomena can result in severe impacts on railway infrastructure. In future, projected changes to the frequency and/or intensity of extreme weather events could change weather–infrastructure risk profiles. Infrastructure owners and operators need to manage current weather impacts and put in place adequate plans to anticipate and adapt to ch...

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 decreased,...

Determination of the relevant soil stratigraphy is of the paramount importance for any geotechnical analysis. The cone penetration test (CPT) is the cost-effective, rapid, continuous, and reliable testing method for assessing soil layering and estimating in-situ mechanical properties of soil, and as such is especially useful for subsoil investigati...

This paper presents a case study focused on the Brajdica railway tunnel, which carries the Zagreb-Rijeka railway line into the port of Rijeka in Croatia and thus represents a critical node on the European TEN-T network. The tunnel is undergoing a major reconstruction project to increase its capacity. As part of this work an extensive embedded monit...

The continuous monitoring of long-term performance of tunnels constructed in soft rock masses shows that the rock mass deformations continue after construction, albeit at a rate that reduces with time. This is in contrast with NATM postulates which assume deformation stabilizes shortly after tunnel construction. This paper proposes the prediction o...

Aged earthworks constitute a major proportion of European rail infrastructures, the replacement and remediation of which poses a serious problem. Considering the scale of the networks involved, it is infeasible both in terms of track downtime and money to replace all of these assets. It is, therefore, imperative to develop a rational means of manag...

The majority of installed offshore wind turbines are supported on large‐diameter, open ended steel pile foundations, known as monopiles. These piles are subjected to vertical and lateral loads while in service. In current design practice, interaction of vertical and lateral loads are not considered, rather piles are designed to resist vertical and...

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 affec...

Tidal-stream (tidal) energy is a renewable form of energy produced by harnessing the kinetic energy of marine currents created by the rise and fall of the tides and converting it into electricity. To-date, tidal energy development remains largely in the demonstration stage and the development community has not rallied behind any one foundation tech...

Pile driveability is affected by, amongst other factors, the pore pressure changes in the vicinity of the pile. However, accurate quantification of the generated pore pressure in the soil layer during impact pile driving is a challenging task, especially in the small-scale models. An electro-mechanical miniature impact pile driver has been designed...

Offshore wind developments are moving towards deep-water regions where energy is abundant, visual impact is minimised and the larger turbine sizes can make the energy production more cost-effective. One of the key challenges facing the industry is the development of reliable substructures. While fixed foundation systems are widely used for shallow-...

This paper investigates the applicability of Cone Penetration Test (CPT)‐based axial capacity approaches, used for estimating pile static capacity, to the prediction of pile driveability. An investigation of the influence of various operational parameters in a driveability study is conducted. A variety of axial capacity approaches (IC‐05, UWA‐05 an...

This paper offers a solution to overcome time-consuming numerical analysis for the evaluation of the impact of tunnel construction in a complex karst environment by implementing Monte-Carlo simulation (MCS) using a neural network (NN) tool. The rock mass is described using three parameters, Geological Strength Index, the uniaxial compression streng...

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 piles,...

This paper describes a one-dimensional (1D) computational model for the analysis and design of laterally loaded monopile foundations for offshore wind turbine applications. The model represents the monopile as an embedded beam and specially formulated functions, referred to as soil reaction curves, are employed to represent the various components o...

Offshore wind turbines in shallow coastal waters are typically supported on monopile foundations. Although three-dimensional (3D) finite-element methods are available for the design of monopiles in this context, much of the routine design work is currently conducted using simplified one-dimensional (1D) models based on the p–y method. The p–y metho...

In the current economic climate, it is crucial to optimize the use of all resources regarding railway infrastructure maintenance. In this paper, a multi-attribute decision support framework is applied to categorize railway embankments in order to prioritize maintenance activities. The paper describes a methodology to first determine the current con...

Rock bolts represent a critical element for many rock mass stabilization, tunnel construction, and underground work projects. Therefore, the evaluation of their condition is vital for proving their functionality over the entire life-cycle of structures. A number of techniques for quantifying condition of rock bolts are presently applied or are bein...

Because of the deltaic nature of the Netherlands, deep soft soil deposits are widespread. Due to the population density exploitation of underground space is vital for commercial developments and transport networks. Piles are used as primary support elements in deep excavations, cut and cover tunnels, quay walls, flood defences and to provide uplift...

The design of axially loaded piles has been an area of focus for the offshore industry in recent years. A number of studies report substantial increases in the shaft capacity of piles driven in sand, known as pile ageing. The offshore industry has been slow to implement ageing into practice because of uncertainty over the mechanisms controlling age...

Knowledge of the fines content is necessary for all soil classification systems and an important factor in the evaluation of soil strength in liquefaction and seismic settlement analysis. This paper presents the application of cone penetration test, CPT data for estimating the soil fines content. The correlation can be used either as a first estima...

The effect of scour hole shape on the lateral capacity of monopiles, as the foundation of offshore wind turbines, in a sand layer has been investigated both experimentally and numerically. The experimental programme consists of 4 centrifuge tests at 100g on a 1.8 m rigid monopile with original embedment of 5 times the pile diameter (5D). Three type...

This paper provides a summary of the PIle Soil Analysis (PISA) project, completed in the UK during the period 2013 to 2018. The research led to the development of a new, computationally efficient, one dimensional design model for laterally loaded monopile foundations, particularly for offshore wind turbine support structures. The current form of th...

This study presents a probabilistic analyses of suction bucket installation in cohesionless soils. The spatial variability of soil properties is quantified using a representative survey dataset from practice. Vertical random field modelling is used to model cone resistance variability and probability density functions are fitted using drained param...

This paper investigates the influences that steel type, in situ soil properties, water table depth, pile diameter, roughness and driving procedures have on the ageing behaviour of piles driven in sand. Tension tests have been performed on 51 open-ended steel micro-piles, with 48 to 60 mm outside diameter, driven at well-established research sites a...

The dynamic response of structures in contact with soil is receiving increasing interest and there is a growing need for more accurate models capable of simulating the behaviour of these systems. This is particularly important in the field of offshore wind turbines, where accurate estimates of system frequency are needed to avoid resonance, and in...

The paper describes the site characterization of a dense sand test site developed by the authors in an active quarry located near the village of Blessington, Ireland. The site has been used to investigate the field response of a number of foundation systems including jacked closed and open-ended piles, driven concrete and steel open-ended piles, sh...

This paper presents an experimental and analytical study to investigate the effect of shape on the pull-out capacity of shallow horizontal plate anchors in sand under drained loading conditions. Novel dynamically penetrating plate anchor concepts have been proposed for use in the offshore energy sector. These anchor concepts may have shapes that ar...

This paper provides a brief overview of the Pile Soil Analysis (PISA) project, recently completed in the UK. The research was aimed at developing new design methods for laterally loaded monopile foundations, such as those supporting offshore wind turbine structures. The paper first describes the background to the project and briefly outlines the ke...

An important aspect regarding the sustainability of steel structures is to ensure the structure is protected from corrosion. A number of surface coatings are available that play an important role in protecting these structures. An important part of the management of these structures is reliable and regular inspection along with methods for early de...

There have been significant developments in the area of vibration-based bridge scour monitoring in recent years. Traditional scour monitoring using either visual assessment or diving inspections are now recognised to be very unreliable and highly subjective. There has been a concerted effort to move towards reliable systems capable of either direct...

There has been significant progress made in the area of vibration-based bridge scour monitoring in recent years. Traditional scour monitoring using visual-type inspections relied on divers investigating the condition of bridge foundations and manually locating and measuring scour holes. This is now considered very unreliable and highly subjective,...

Offshore pile driving is a high-risk activity as delays can be financially punitive. Experience of pile driving for offshore jacket structures where pile diameters are typically < 2m has led to the development of empirical pile driveability models with proven predictive capability. The application of these methods to larger diameter piles is uncert...

Bridges can be subjected to damaging environmental actions due to flooding and seismic hazards. Flood actions that result in scour are a leading cause of bridge failure, while seismic actions that induce lateral forces may lead to high ductility demand that exceeds pier capacity. When combined, seismic actions and scour can lead to effects that dep...

Several regions in Europe are prone to both seismic and scour hazards thus bridges can suffer from the joint actions of these two phenomena. The two types of hazards are actually independent as to the generation process but the loss of surrounding soil due to scour may significantly modify the dynamic parameters of the structure thus changing its r...

Pile foundations used for offshore wind structures are subjected to large lateral loading from wind and waves while in service as well as significant vertical loading from the top structure. Erosion of soil from around these structures, termed scour, poses a significant problem for the structural stability. In order to better understand the perform...