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The installation procedure is one of the most critical and important stages of the design and installation of offshore wind turbines (OWT). Among the various steps of installation, the launching process is the most critical operation. As a cost-effective way, the launching technique is preferred, rather than lifting it directly using a heavy lift vessel. In this Master Thesis, an evaluation of logistics concepts for transporting and installing offshore floating wind components has been performed.
To ensure safe and effective launching, the entire operation has to be mathematically modeled and numerically simulated and the results to be scrutinized thoroughly to verify the operation complies with the class rules and current regulations. As part of this thesis, different phases of launching have been identified and corresponding equations of motions with necessary constraints are developed. The ship’s coupled motions (pitch & heave motion) are mathematically modeled and a time-dependent numerical simulation of the operation is made to assess the dynamic trim, velocities, and accelerations experienced by the vessel during the launching of the wind turbine fundament (SPAR). A computer code has been developed to solve the mathematical models and generate required plots to analyze the results. The required added mass coefficients including coupled ones are calculated by integrating the sectional added mass with the help of Lewis conformal mapping. Whereas damping coefficients are obtained from the critical damping and restoring coefficients from respective empirical formulas.
All results are verified against current rules and regulations. The maximum values of the pitch angle, pitch angular velocity, pitch angular acceleration, heave displacement, heave velocity and heave accelerations are within the allowable limits. This study gives insight into the ship’s dynamics at the critical stage of the launching sequence. Further studies are required to check the structural integrity of the ship during the launching operation.

Launching, SPAR, Mathematical Modelling, Hydrodynamic Coefficient, Added Mass, Coupled Pitch-Heave Motion, Strip Theory, Lewis Conformal Mapping --- Ingénierie, informatique & technologie > Ingénierie mécanique

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Prepared by the Frozen Ground Committee and the Transportation and Infrastructure Committee of the Cold Regions Engineering Division of ASCEFrost Action in Soils: Fundamentals and Mitigation in a Changing Climate presents the challenges of cold regions engineering in a changing climate, as well as the current practices and state-of-the-art tools for addressing them. Climate change poses questions regarding associated effects on freeze–thaw action and the potential impacts on pavements and other structures in cold regions. In the last 35 years, significant technological advancements addressing frost action in soils have occurred; and tools for instrumentation, measurement, and computer analysis have improved considerably. Thebook explores frost action in soils from different perspectives, as presented in three parts. The first section presents the fundamentals of frost heave and thaw weakening, the impacts on roads and other structures, and the projected effects of climate change on frost action. The second section presents mitigation of frost heave and thaw weakening within pavement structures. The third section highlights three case studies dealing with frost action and mitigation for buildings, roadways, and airfields. This book is a valuable resource for engineers, scientists, and government agencies involved in cold regions engineering and the mitigation of frost action on pavements and other structures.

Frost heaving. --- Frozen ground. --- Soil freezing. --- Frost --- Mitigation and remediation --- Cold regions --- Case studies --- Freeze and thaw --- Frozen soils --- Frost heave --- Cold regions engineering --- Frost --- Mitigation and remediation --- Cold regions --- Case studies --- Freeze and thaw --- Frozen soils --- Frost heave --- Cold regions engineering

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The broad use of composite materials and shell structural members with complex geometries in technologies related to various branches of engineering has gained increased attention from scientists and engineers for the development of even more refined approaches and investigation of their mechanical behavior. It is well known that composite materials are able to provide higher values of strength stiffness, and thermal properties, together with conferring reduced weight, which can affect the mechanical behavior of beams, plates, and shells, in terms of static response, vibrations, and buckling loads. At the same time, enhanced structures made of composite materials can feature internal length scales and non-local behaviors, with great sensitivity to different staking sequences, ply orientations, agglomeration of nanoparticles, volume fractions of constituents, and porosity levels, among others. In addition to fiber-reinforced composites and laminates, increased attention has been paid in literature to the study of innovative components such as functionally graded materials (FGMs), carbon nanotubes (CNTs), graphene nanoplatelets, and smart constituents. Some examples of smart applications involve large stroke smart actuators, piezoelectric sensors, shape memory alloys, magnetostrictive and electrostrictive materials, as well as auxetic components and angle-tow laminates. These constituents can be included in the lamination schemes of smart structures to control and monitor the vibrational behavior or the static deflection of several composites. The development of advanced theoretical and computational models for composite materials and structures is a subject of active research and this is explored here for different complex systems, including their static, dynamic, and buckling responses; fracture mechanics at different scales; the adhesion, cohesion, and delamination of materials and interfaces.

Technology: general issues --- dynamic stability --- elastomeric foundation --- Eringen’s differential constitutive model --- graphene sheet --- temperature-dependent properties --- basement bottom reinforcement --- reinforcement depth --- Young’s modulus of reinforced soil --- tunnel heave --- numerical analysis --- epistemic uncertainty --- evidence theory --- robust optimization --- sensor design --- near-field earthquake --- fling-step --- far-field --- simultaneous excitation --- special moment frame (SMF) --- advanced model --- precise prediction --- circular foundation pit --- tunnel deformation --- composite --- stochastic --- natural frequency --- uncertainty --- metro constructions --- shield tunnel --- ground settlement --- soil displacement --- analytical --- Mindlin solution --- EELS --- plasmons vibrational modes --- nanoparticles --- nonlocal and size-dependent dielectric --- nanoparticle suspension --- Brownian motion --- spectral thermal pulsing --- DEM simulations --- Nano-device applications --- stratum movements --- mirror source–sink method --- centrifuge modelling test --- transport --- palletized goods --- damage --- bottle --- buckling --- Polyethylene terephthalate (PET) --- n/a --- Eringen's differential constitutive model --- Young's modulus of reinforced soil --- mirror source-sink method

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Ocean Structures subjected to actions of ocean waves require safety inspection as they protect human environment and everyday lives. Increasing uses of ocean environment have brought active research activities continuously. The newly developed technology of ocean energy even pushed the related needs forward one more step. This Special Issue focuses on Analysis of Interactions between wave structures and ocean waves. Although ocean structures may cover various practical and/or conceptual types, we hope in the years to come, the state-of-the-art applications in wave and structure interactions and/or progress review and future developments could be included. There are fifteen papers published in the Special issue. A brief description includes: Lee et al. [1] presented a concept of a water column type wave power converter. Li et al. [2] considered submerged breakwaters. Lin et al. [3] studied an ocean current turbine system. Thiagarajan and Moreno [4] investigated oscillating heave plates in wind turbines. Chiang et al. [5] proposed an actuator disk model. Tseng et al. [6] investigated Bragg reflections of periodic surface-piercing submerged breakwaters. Lee et al. [7] analyzed caisson structures with a wave power conversion system installed. Yeh et al. [8] reported motion reduction in offshore wind turbines. Wu and Hsiao [9] considered submerged slotted barriers. Tang et al. [10] studied floating platforms with fishnets. Chen et al. [11] calculated mooring drags of underwater floating structures with moorings. Jeong et al. [12] estimated the motion performance of light buoys using ecofriendly and lightweight materials. Zhang et al. [13] considered vibrations of deep-sea risers. On the other hand, Shugan et al. [14] studied the effects of plastic coating on sea surfaces.

Technology: general issues --- deep-sea riser --- top tension --- vortex-induced vibration --- numerical simulation --- experiment --- light buoy --- motion performance in waves --- potential-based simulations --- viscous damping coefficients --- free decay tests --- computational fluid dynamics --- analytic solution --- water waves --- underwater floating structure --- mooring forces --- interaction --- floating platform --- fishnet mesh size --- frequency-domain --- time-domain --- nonlinear waves --- BEM --- solitary wave --- submerged breakwater --- slotted barrier --- PIV --- RANS model --- motion reduction control --- renewable energy --- TLD --- offshore wind turbine --- structural safety --- breakwater design --- wave energy --- wave power converting system --- caisson breakwater application --- eigenfunction matching method --- oblique wave --- Bragg reflection --- step approximation --- surface-piercing structure --- periodic bottom --- surface waves --- wave breaker --- elastic plate --- power prediction --- capacity factor --- actuator disk --- wind farm --- heave plate --- free surface effect --- floating offshore wind turbine --- hydrodynamic coefficients --- added mass --- damping coefficient --- forced oscillation in waves --- Keulegan Carpenter number --- stability --- ocean current power system --- surface type --- buoyance platform --- mooring foundation --- particle image velocimetry --- submerged obstacle --- undulating breakwater --- rectangular breakwater --- vortex energy --- offshore wind power --- template structure system --- oscillating water column --- typhoon --- gust --- extreme wind --- aerodynamic load --- deep-sea riser --- top tension --- vortex-induced vibration --- numerical simulation --- experiment --- light buoy --- motion performance in waves --- potential-based simulations --- viscous damping coefficients --- free decay tests --- computational fluid dynamics --- analytic solution --- water waves --- underwater floating structure --- mooring forces --- interaction --- floating platform --- fishnet mesh size --- frequency-domain --- time-domain --- nonlinear waves --- BEM --- solitary wave --- submerged breakwater --- slotted barrier --- PIV --- RANS model --- motion reduction control --- renewable energy --- TLD --- offshore wind turbine --- structural safety --- breakwater design --- wave energy --- wave power converting system --- caisson breakwater application --- eigenfunction matching method --- oblique wave --- Bragg reflection --- step approximation --- surface-piercing structure --- periodic bottom --- surface waves --- wave breaker --- elastic plate --- power prediction --- capacity factor --- actuator disk --- wind farm --- heave plate --- free surface effect --- floating offshore wind turbine --- hydrodynamic coefficients --- added mass --- damping coefficient --- forced oscillation in waves --- Keulegan Carpenter number --- stability --- ocean current power system --- surface type --- buoyance platform --- mooring foundation --- particle image velocimetry --- submerged obstacle --- undulating breakwater --- rectangular breakwater --- vortex energy --- offshore wind power --- template structure system --- oscillating water column --- typhoon --- gust --- extreme wind --- aerodynamic load

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Ocean Structures subjected to actions of ocean waves require safety inspection as they protect human environment and everyday lives. Increasing uses of ocean environment have brought active research activities continuously. The newly developed technology of ocean energy even pushed the related needs forward one more step. This Special Issue focuses on Analysis of Interactions between wave structures and ocean waves. Although ocean structures may cover various practical and/or conceptual types, we hope in the years to come, the state-of-the-art applications in wave and structure interactions and/or progress review and future developments could be included. There are fifteen papers published in the Special issue. A brief description includes: Lee et al. [1] presented a concept of a water column type wave power converter. Li et al. [2] considered submerged breakwaters. Lin et al. [3] studied an ocean current turbine system. Thiagarajan and Moreno [4] investigated oscillating heave plates in wind turbines. Chiang et al. [5] proposed an actuator disk model. Tseng et al. [6] investigated Bragg reflections of periodic surface-piercing submerged breakwaters. Lee et al. [7] analyzed caisson structures with a wave power conversion system installed. Yeh et al. [8] reported motion reduction in offshore wind turbines. Wu and Hsiao [9] considered submerged slotted barriers. Tang et al. [10] studied floating platforms with fishnets. Chen et al. [11] calculated mooring drags of underwater floating structures with moorings. Jeong et al. [12] estimated the motion performance of light buoys using ecofriendly and lightweight materials. Zhang et al. [13] considered vibrations of deep-sea risers. On the other hand, Shugan et al. [14] studied the effects of plastic coating on sea surfaces.

deep-sea riser --- top tension --- vortex-induced vibration --- numerical simulation --- experiment --- light buoy --- motion performance in waves --- potential-based simulations --- viscous damping coefficients --- free decay tests --- computational fluid dynamics --- analytic solution --- water waves --- underwater floating structure --- mooring forces --- interaction --- floating platform --- fishnet mesh size --- frequency-domain --- time-domain --- nonlinear waves --- BEM --- solitary wave --- submerged breakwater --- slotted barrier --- PIV --- RANS model --- motion reduction control --- renewable energy --- TLD --- offshore wind turbine --- structural safety --- breakwater design --- wave energy --- wave power converting system --- caisson breakwater application --- eigenfunction matching method --- oblique wave --- Bragg reflection --- step approximation --- surface-piercing structure --- periodic bottom --- surface waves --- wave breaker --- elastic plate --- power prediction --- capacity factor --- actuator disk --- wind farm --- heave plate --- free surface effect --- floating offshore wind turbine --- hydrodynamic coefficients --- added mass --- damping coefficient --- forced oscillation in waves --- Keulegan Carpenter number --- stability --- ocean current power system --- surface type --- buoyance platform --- mooring foundation --- particle image velocimetry --- submerged obstacle --- undulating breakwater --- rectangular breakwater --- vortex energy --- offshore wind power --- template structure system --- oscillating water column --- n/a --- typhoon --- gust --- extreme wind --- aerodynamic load