Mono Piles Foundation installation/نصب شاسی توربین های بادی فراساحل

Mono Piles Foundation installation

Depending on the foundation type, the installation vessel and strategy may differ.

Currently, approximately 90% of offshore wind turbines are installed on monopiles and the remainder are installed on jackets, tripods or gravity-based support structures.

There are also a few demonstration floating turbines, which have no bottom-fixed

foundations.

Mono piles

The the foundation pile or Mono pile (MP) support structure is a relatively simple design by which the tower is supported by the mono pile, either directly or through a  Transition piece or (Transition Platform) (TP). One of the main advantages of the mono pile foundation is the easy application for a large number of wind turbines. A large number of piles can be transported to the building site by the installation vessel itself or by a transportation barge. The next step is the installation of the  scour protection (static scour protection), although it is possible to install scour protection after pile installation (dynamic scour protection).  The foundation used is a steel monopile, 45m long on average with a diameter of 4,6m and a wall thickness of 40 to 60mm. Its weight is approx. 230 tons. These piles were made at Bladt industries in Denmark.

The transition piece is lifted and placed on the top of the monopile and then the space between the monopile and the transition piece (about 10e20 cm thick) is

grouted. The top of the transition piece is used as the work platform and the sides

are used for boat landing and ladder placement The mono pile continues down into the seabad.

Monopiles are large hollow steel or concrete tubes, whose thickness and diameter vary

based on the turbine size, soil condition , water depth and hydrodynamic loads on the monopile portion: wave, current, and ice loads, seismic loads.The effects of wave and current kinematics on the loading of a monopile tower can be

calculated via the Morison equation for slender members

wind-generated, near surface currents, and subsurface currents generated by tidal motion, storm surges, and atmospheric pressure Variations

Before installation of a monopile, a layer of scour protection should be applied to avoid seabed erosion around the monopile. This first scour protection layer is made by rock dumping around the monopile position. When the first layer of scour protection is made, monopiles are lifted from the installation vessel and then positioned on the seabed.

Common installation methods of monopiles are pile driving using a hydraulic hammer or pile drilling .

On average it takes about one or two days to install a monopile using these methods. If pile driving using a hydraulic hammer is chosen,depending on the seabed condition and water depth, it takes about 2000 to 3000 hammer hits to drive the monopile into the ground. During the pile driving or drilling,the piling depth is continuously monitored to make sure the monopile is placed into the correct depth.

The installation sequence of the pile starts with lifting it into position by a large crane or heavy lift vessel. The pile will be lifted from a floating position, afterwards the bulk heads will be removed and then the open ended pile can be aligned into position. This will be done by an alignment tool at a certain distance above the sea level, as can be seen in Figure. The pile will penetrate into the seabed due to its own weight, depending on the soil conditions. To drive the pile into the ground, a hydraulic hammer is lifted onto the pile, or the pile can be drilled in case of very hard soil.

Around the foundation a layer of rocks was placed to provide scour protection. As seawater flows around the monopile it creates turbulence which erodes the seabed sand directly around the monopile (this is the actual scour process) and so endangers the

stability of the foundation. The scour protection prevents the sand from being eroded away. In total about 50.000 tons of stone have been installed on the seabed around the monopiles (see also Figure below).

In figure a schematic overview is given on the major parts of an offshore windmill 

At the bottom of the wind turbine is the foundation pile or monopile (MP

This is a simple steel tube that is hammered into the seabed. Because it is hammered, it cannot be guaranteed that it is perfectly vertical. Also the top of the pile gets damaged in this process  

Indicated in yellow is the Transition Piece (TP). Typical characteristics are as follows: the lower 6m of this 25m high structure slides over the top of the monopile. Jacks are used to align the TP vertically to correct the MP skewness. Then the space between the TP and MP is grouted to fix the connection.

Furthermore the top of the TP offers a nice flange for the tower to be bolted o

After that the tower is installed on top of the TP. The Rotor Nacelle Assembly (RNA) is installed on top of the tower, sometimes in one go, and sometimes first the nacelle is installed and then each

blade independently afterwards.

The suction pile can also be a support structure in combination with a monopole on top of it . The suction pile is relatively short in relation to the diameter, and therefore called pile, but the

diameter can be larger compared to the length and in that case it is called a suction can or suction anchor . The main principle behind the suction anchor is the pressure difference, which is createdby pumping the water out of the pile or can while it is placed upside down on the seabed. The pressure difference is the main driving force to drive the pile into the seabed, and therefore this support structure is less suitable for shallow waters. Furthermore, the tension capacities and bending moment capacities might be lower compared to a pile foundation. The suction pile is not taken into account any further.

همانطور که در بالای متن هم اشاره شد شاسی برخی  توربین های بادی فراساحل به صورت فلزی و بتن است ضربه چکش های به شاسی توربین های بادی فراساحل اکوسیستم آبزیان دریایی را به خطر می اندازد برای حفظ اکوسیستم دریایی از این روش استفاده می کنند دستگاه حفاری را داخل شاسی توربین بادی فراساحلی قرار می دهند بعد از حفاری و قرار گرفتن شاسی توربین بادی فراساحلی داخل آن را با بتن پر می کنند

Monopiles are typically used in shallow water depths, but may become too flexible for water depths of between w30 and 40 m, in which case monopiles fitted with guy wires, or alternatively tripod and jacket/lattice structures,are considered as economical alternatives. For greater depths, time-consuming

installation and the effect of soil degradation, which occurs around the pile shaft at seabed level, make monopile foundation solutions prohibitive

امیدوارم در فیلم های بعدی توضیح بیشتری درباره این سازه و نحوه چیدمان حلقه ، جوش پودری ، تست جوش و دیگر مراحل این سازه بنویسم .

هدف از نمایش این فیلم نحوه انتقال سازه به محل پروژه بود انتقال این سازه به دو روش است سوار کردن روی بارج یا شناور کردن این سازه و کشیدن ان توسط یدک است همه اینها بستگی به طول سازه دارد.

این پروژه ها توسط سرمایه گذاری مشترک چندین کشور اورپایی انجام می شود که برای مراحل انجام هر کاری یا قسمتی از آن در کشورهایشان سرمایه گذاری شده است و امروزی برای کم هزینه کردن این پروژه ها در حال مطالعه هستند تا بتواند هم تجهیزات کم هزینه استفاده شود هم برنامه زمان بندی آن را کاهش دهند.در قسمت های بعدی درباره کارخانه ساخت شاسی توربین های فراساحل بیشتر خواهم نوشت

Frontiers in Offshore Geotechnics III,Vaughan Meyer,CRC Press,2015

این کتاب درباره سرحدهای ژئوتکنیک فراساحلی می باشد، که دارای 1398 صفحه و در 2 جلد می باشد. مجموعه ای از مقالات ارسالی به موسسه ژئوتکنیک نروژ می باشد که توسط Vaughan Meyer جمع آوری شده است. با این عناوین

Frontiers in Offshore Geotechnics III,Vaughan Meyer,CRC Press,2015
The titles

This file is password

Password: CE-MS MS.c Bijan Mohammadi

All text and change the color to use to download it

دانلود/Download                  کلمه عبور/ Password                                                                                                       

                                                           

Volume 1

*Keynotes

The suction foundation technology

Geotechnics for wells top-hole section and conductor

The effects of pile ageing on the shaft capacity of offshore piles in sand

A FE procedure for calculation of cyclic behaviour of offshore foundations under partly drained conditions

Geohazard risk evaluation and related data acquisition and sampling program for the methane hydrate offshore production test

Deterministic and probabilistic advances in the analysis of spudcan behavior

*Suction anchors and caissons

Installation of suction caissons for an asymmetrical support structure in sandy soil

Simplified earthquake analysis for wind turbines and subsea structures on closed caisson foundations

Laterally loaded suction caissons with aspect ratio of one

Seismic response of bucket foundations for offshore wind tower using dynamic centrifuge tests

Friction degradation and strength regain along suction piles in soft deep water Gulf of Guinea clays

Suction pile foundation for a PLET subsea structure

Suction caisson extraction resistance in Gulf of Guinea clay

Performance of a shallow skirted foundation for TLP mooring in carbonate silt

Calculation of undrained holding capacity of suction anchors in clays

Interpretation of centrifuge tests of suction anchors in reconstituted soft clay

CAISSON_VHM: a program for caisson capacity under VHM load in undrained soils

Suction anchor geotechnical design practice: A case study

Centrifuge model test for bearing capacity evaluation of hybrid suction foundation on clay under vertical and horizontal loads

Pullout resistance of horizontal and inclined loaded suction anchor installed in silty sand via centrifuge modelling

Skirt penetration resistance in carbonate soils from the CPT

Horizontal capacity of multiple suction anchors using numerical analysis

Dynamic behaviour of mono bucket foundations subjected to combined transient loading

Novel monitoring solutions solving geotechnical problems and offshore installation challenges

Effect of torsion on suction piles for subsea and mooring applications

Comparison of design methods for axially loaded buckets in sand

Caisson capacity in undrained soil: Failure envelopes with internal scooping

P–y curves for bucket foundations in sand using finite element modeling

*Pipelines, risers and subsea earthworks

Seabed stiffness model for steel catenary risers

Ultimate uplift capacity of buried pipelines in undrained clay

Evaluation of a toroid for model pipeline testing of very soft offshore box core samples

Excess pore pressure redistribution beneath pipelines: FEA investigation and effects on axial pipe-soil interaction

Pipeline embedment and consolidation beneath on-bottom pipe model in kaolin clay

The soil strength degradation influence in the axial pipe-soil resistance

Pipe-Soil Interaction: Recent and future improvements in practice

Predicted and observed settlements of a subsea rock installation – comparison between field measurements and FE simulations of soft North Sea clay

Effects of different loading time histories on fatigue design of steel catenary risers using nonlinear riser-soil interaction models

A new torsional shear device for pipeline interface shear testing

Large scale experiments on the riser-soil interaction in clay

An integrated approach to pipeline burial in the 21st century – The current state-of-the-art

Direct shear interface tests for pipe-soil interaction assessment

Evaluation of pipe-soil interaction in liquefied soil

Pipe-soil interaction under rapid axial loading

Mechanical trencher modelling in hard ground: State-of-the-art

Finite element analysis of soil damping for pipeline slugging

Geotechnical considerations for pipeline stabilization design using rock berms

Pipe-soil interaction mechanism during pipeline upheaval buckling in loose saturated sand

Study of vertical pipe-soil interaction based on Coupled Eulerian-Lagrangian method

Stress level effects on plane-strain pipe uplift resistance

Theoretical analysis and model test for pipeline protection from dragged anchors

A discrete element study on upheaval ratcheting behavior of pipelines buried in sand

An investigation on existing nonlinear seabed models for riser-fluid-soil interaction studies in steel catenary risers

Geotechnical design and construction aspects of a pipeline-escarpment crossing

*Piled foundations

Modelling of laterally loaded screw piles with large helical plates in sand

Design methodology for cyclically and axially loaded piles in chalk for Wikinger OWF

Full scale offshore verification of axial pile design in chalk

Centrifuge investigation of the axial cyclic behaviour of a single pile used for the foundation of a jacket type offshore wind turbine

Review of pile driving results for the Maui and Maari developments in the Taranaki basin of New Zealand

Cyclic pile load tests combined with laboratory results to design offshore wind turbine

Foundations in chalk

Comparison of pile bearing capacity from CPT and dynamic load tests in clay considering soil setup

The use of pipe piles for creating ice protection barrier

Improvement of bearing capacity of vibratory driven open-ended tubular piles

Small strain overlay to the API p-y curves for sand

Boulder-soil-pile dynamic interaction

Driven pile design in weak rock

Effect of soil set-up during interruption of offshore pile driving

Axial capacity design practice for North European wind-turbine projects

Lessons learned from pile driving and monitoring in gravels on the Northstar Artificial Island

Innovative design of foundations – offshore wind farm substation

A preliminary experimental study on the mechanism of local scour at pile groups in steady currents

Interpretation difficulties of pile set-up in sand

Evolution of driving resistance during driven pile installation

CPT-based pile shaft friction in calcareous sands of western Indian offshore

Synthesis of pile driving data in South East Asia

Case studies – predicting soil resistance to driving in South East Asia

Axial capacity ageing trends of piles driven in silica sands

In situ and laboratory tests in dense sand investigating the helix-to-shaft ratio of helical piles as a novel offshore foundation system

Re-assessment of pile driveability predictions on sites offshore Nigeria

Numerical implementation of soil-pile interaction models for monotonic and reversed axial loading

Ultimate lateral resistance of laterally loaded piles in undrained clay

Deepwater jetted piles: Numerical modeling of jetting action and axial bearing capacity

Centrifuge model tests on laterally monotonic and cyclic pile-soil interaction of a tetrapod jacket foundatio

*Monopiles

Model pile response to multi-amplitude cyclic lateral loading in cohesionless soils

On the development of a hybrid foundation for offshore wind turbines

Alternative p-y curve formulations for offshore wind turbines in clays

Improving the lateral resistance of offshore pile foundations for deep water application

New design methods for large diameter piles under lateral loading for offshore wind applications

Cyclic lateral loading of monopiles for offshore wind turbines

Observed variations of monopile foundation stiffness

Design of large diameter monopiles in chalk at Westermost Rough offshore wind farm

Influence of vertical loads on the behavior of laterally loaded large diameter pile in sand

Predicting monopile behaviour for the Gode Wind offshore wind farm

Evaluation of a new p-y approach for piles in sand with arbitrary dimensions

Experimental trends from lateral cyclic tests of piles in sand

Effect of relative pile’s stiffness on lateral pile response under loading of large eccentricity

Numerical modelling of large diameter piles under lateral loading for offshore wind applications

Volume 2

*Shallow foundations

Prediction and worked example for a sliding foundation on soft clay

Effects of drainage on the response of a sliding subsea foundation

Undrained bearing capacity of skirted mudmats on inclined seabeds

Three-dimensional limit analysis of rectangular mudmat foundations

Collision of double hull tanker with gravity base foundation of offshore wind turbine: case of horizontal drift and swell

Some key aspects in geotechnical design of GBS foundations on sand

A framework for the design of sliding mudmat foundations

Undrained vertical bearing capacity of perforated shallow foundations

Simulation of a full-scale test on a gravity base foundation for offshore wind turbines using a high cycle accumulation model

System integration of direct on-seabed sliding foundations

*Anchoring systems

Pullout capacity of plate anchors in sand for floating offshore wind turbines

Centrifuge model study on pullout behavior of plate anchors in clay with linearly increasing strength

Large deformation numerical analysis of plate anchor keying process

The role of partly remoulded clay in fluke and plate anchor design

Numerical modeling of drag anchors of floating structures – comparison of ultimate holding capacity with limit equilibrium methods

Design and performance of suction embedded plate anchors

Soil flow mechanism around deeply embedded plate anchors during monotonic and sustained uplifts

Comparison between FEM analyses and full-scale tests of fluke anchor behavior in silty sand

Dynamically Installed Anchors: Performance of embedded mooring chain profile in clay

A review of anchor technology for floating renewable energy devices and key design considerations

Numerical modelling of the SEPLA during keying process

Behavior of Suction Embedded Plate Anchors with flap during keying in clay

Chain configuration in sand, theory and large scale field testing

Cyclic response of shallow helical anchors in a medium dense sand

Numerical investigation on line tension-induced pore pressure accumulation around an embedded plate anchor

Behaviour of OMNI-Max anchors under chain loading

ایده طراحی لنگر OMNI-MAX بر گرفته از لنگرهای مکش دیگر از جمله لنگر مکش صفحه جا سازی شده می باشد دامنه درگیر این سازه نسبت به لنگر مکشی بیشتر است این لنگر فوق در ایالات متحده آمریکا به شماره ثبت اختراع 7059263 ثبت شده است. در مورد لنگرها در همین وبلاگ دنیای سازه های دریایی درباره آن نوشته شده است.

این مقاله درباره لنگر OMNI-MAX می باشد

All text and change the color to use to download it

کلمه عبور/Password                                           دانلود/Download

*Geohazards and integrated studies

Predictions of ice scour loads from small scale tests under 1 g conditions

Areas 2 and 5 offshore Mozambique: Mass-movements on a deep-water margin with scant adjacent shelf

Turbidity current hazard assessment for field layout planning

Bayesian mechanistic imaging of two-dimensional heterogeneous elastic media from seismic geophysical observations

Optimization of deep-water pipeline routes in areas of geologic complexity – an example from the Southern Gulf of Mexico

Understanding the element of time in probabilistic submarine slope stability analyses 

Effect of fines on mechanical properties of methane hydrate bearing sands

Numerical analysis of submarine debris flows based on critical state soil mechanics

The life cycle of geohazards within an offshore engineering development

Numerical analysis of stability of seafloor slope under linear waves

Offshore 1D infinite slope modeling in seismic conditions with OpenSees

Numerical simulations of shallow gas migration in vicinity of platforms in offshore Malaysia: Effects of relief wells on excess pore pressure dissipation

Geotechnology – Converting site investigations into 3D geotechnical models

Weak interlayers effects on seismic performance of a deepwater slope

Integration of very-high-resolution seismic and CPTU data from a coastal area affected by shallow landsliding – the Finneidfjord natural laboratory

Influence of gas hydrate dissociation on mechanical properties of gas hydrate-bearing sediment

*Soil characterisation and modelling

Effect of pore pressure build-up on the seismic response of sandy deposits

Potential of estimating relative density by measuring shear wave velocity in field and in laboratory

Strength of a carbonate silt at the solid-fluid transition and submarine landslide run-out

Results of geotechnical characterization in the laboratory of clays from offshore Mozambique

Temperature effects on laboratory measured strength on deep water soft clays

Procedures for estimating hysteretic foundation damping

Development of nonlinear foundation springs for dynamic analysis of platforms

Planning of soil investigation for GBS foundation design

Characterization of in-situ effective stress profiles in clays based on piezo-cone penetration test (CPTU) results

New standards and practice of Arctic offshore soil investigation (by Russian experience)

Piezocone evaluation of undrained strength in soft to firm offshore clays

Idealized load composition for determination of cyclic undrained degradation of soils

A new piston sampler for a remotely operated drilling system

Some characteristics of carbonate sediments from North West Shelf, Western Australia

Predictive equations of shear wave velocity for Bay of Campeche sand

Strain ε50 and stiffness ratio (E50/Su) for Gulf of Mexico clays

Suitability of Masing rules for seismic analysis of offshore carbonate sediments

Simulation and experimental study of soil behaviors under principal stress rotations

Strength parameters for suction anchors in a high plasticity Ghana clay

The Maximum-Entropy Meshless method for dynamic and coupled analysis of offshore geotechnical problems

Shear wave velocity and shear modulus in offshore clays

*In situ and laboratory testing

Method dependency for determining maximum and minimum dry unit weights of sands

Shear strength of dense to very dense Dogger Bank sand

Assessment of dissipation tests in silty soils with standard and non-standard decay

Stiffness degradation and damping of carbonate and silica sands

Cyclic laboratory testing of chalk to improve the reliability of piled foundation design

Measurement and interpretation of downhole seismic probe data for estimating shear wave velocity in deep-water environments

The variation of the T-bar bearing capacity factor at shallow depths

Weak fractured rock coring via a seafloor based drilling system – a case study

Measurement uncertainty of offshore Cone Penetration Tests

An instrumented sampler and its application for suction caisson design

Comparison of shear modulus from SCPT, PS logging & laboratory tests of offshore Myanmar

Visualizing the failure surface of a laboratory vane shear in soft clay using transparent surrogate soil

A specialized triaxial testing technique for deep-sea pressure core sediments

Numerical investigation of ball penetrometer performance in dense sand overlying uniform clay

Rock-steel interface testing and considerations for gravity foundations for tidal energy generators

*Jack-up units

The effects of jack-up installation procedures on spudcan capacity in offshore carbonate sediments

A finite element study of boulder interaction with spudcans

Findings of the ISSMGE jack-up leg penetration prediction event

Finite element analyses of spudcan – subsea template interaction during jack-up rig installation

Estimation of spudcan penetration using a probabilistic Eulerian finite element analysis

Calculations of leg penetrations of heavy lift jack-up vessels in multi-layered soils

Effects of consolidation during spudcan installation in carbonate silty clay: A dual approach

Squeezing bearing capacity and effects of increasing strength with depth

Stability assessment of A-shaped mudmats of mobile production units

Linear and nonlinear foundation response in dynamic analyses of jack-up structures

Comparison of coupled and decoupled approaches to spudcan-pile interaction

Sinkage analysis of A-shaped jack-up mudmats using the Coupled Eulerian Lagrangian approach

Mariner and Gina Krog jack-up foundation challenges

A novel spudcan design for improving foundation performance

Jack-up spudcan penetration analysis: Review of semi-analytical and numerical methods

*Design, risk and reliability

A perspective on selecting design strength: Gulf of Mexico deepwater clay

Reliability-based design optimization of laterally loaded monopile foundations for offshore wind turbines

A reliability approach to cable risk assessment

Approach for the calibration of the load and resistance factors for axial pile capacity calculations

Accounting for the spatial variability of soil properties in the reliability-based design of offshore piles

Uncertainty-based characterization of piezocone and T-bar data for the Laminaria offshore site

Comparison of DNV and API design codes for design of suction anchors

به نظر من این مقاله عالی چون مقایسه دو آیین نامه می باشد جالبی این کار هر دو آنها در این موسسه کار می کنند

A safety concept for penetration analyses of suction caissons in sand