Suction Pile Spec

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SUCTION PILE DESIGN SPECIFICATION

EMDC-BRE-C-JS-0332.1001

This cover page is a record of all revisions of the standard/specification identified above by number and title. All previouscover pages are hereby superseded and are to be destroyed.

0 9/12/00 GL !ssued for "eference #ro$ect

REV DATE BY CHKD ENGAPPV

EMDCAPPV

DESCRIPTION

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EXXONMOBILDEVELOPMENTCOMPANY HOUSTON TX

Development Company


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EXXONMOBIL DEVELOPMENTCOMPANY

Suction Pile Design

Specifications

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T!"#$ %& C%'($'()

1. S*%+$...............................................................................................................................1

1.1. !ntroduction............................................................................................................1

1.2. -esign Assumptions..............................................................................................1

2. R$&$,$'*$)......................................................................................................................3

2.1. #ro$ect %pecifications............................................................................................

2.2. !ndustry odes and %tandards.............................................................................

2.. -esign "eports......................................................................................................

3. D$&'(%').......................................................................................................................

.1. General..................................................................................................................

.2. Terms.....................................................................................................................

.. Acronyms...............................................................................................................3

/. P,$-D$)' D$#$,!"#$)................................................................................................

. P#$ L%!).......................................................................................................................4

.1. 'loating %ystems...................................................................................................95.1.1. Mooring.........................................................................................................................................9

.2. %ubsea %ystems..................................................................................................11

.. %uction #ile !nstallation Analysis.........................................................................11

.. Transportation......................................................................................................11

.. Lifting...................................................................................................................11

5. G$%($*6'*!# S7*(%' P#$ D$)'..............................................................................12

4.1. %uction #ile -esign 5asis...................................................................................126.1.1. Floating Systems......................................................................................................................... 126.1.2. Subsea Manifold..........................................................................................................................14

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4.2. -esign.................................................................................................................16.2.1. General........................................................................................................................................ 14

6.2.2. Suction-Installed nc!or "ile Si#ing $Geotec!nical %esign&.................................................... ....15

4.. %uction #ile !nstallation.......................................................................................196.'.1. (mbedment..................................................................................................................................196.'.2. )emo*al................................................................................................................................ ......196.'.'. "ile )etrie*al and )einstallation..................................................................................................2+

4.. Geotechnical -esign -eliverables......................................................................20

8. S(,7*(7,!# S7*(%' P#$ D$)'....................................................................................22

3.1. General -esign "e6uirements............................................................................22,.1.1. Floating Systems......................................................................................................................... 22,.1.2. Subsea Systems........................................................................................................................... 22

3.2. -esign and Analysis............................................................................................22,.2.1. In-"lace Finite (lement nalysis..................................................................................................22,.2.2. lloable Stresses and sage Factors.........................................................................................2',.2.'. /uc0ling !ec0s..........................................................................................................................2',.2.4. Fatigue nalysis.......................................................................................................................... 25,.2.5. Mooring !ain "adeye onnection..............................................................................................26,.2.6. rans3ortation and ift................................................................................................................26,.2.,. Materials elding and Fabrication............................................................................................. 2,,.2.7. lassification of Structural Steel................................................................................................. 2,,.2.9. olerances....................................................................................................................................29

,.2.1+. Metocean riteria........................................................................................................................ 29

3.. orrosion.............................................................................................................29

3.. #aint....................................................................................................................0

3.. Appurtenances....................................................................................................0

. C%9+!': I'($,$'(%'..................................................................................................31

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Suction Pile Design

Specifications

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1. S*%+$

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!is document describes t!e general geotec!nical and structural design re8uirements for t!esuction installed mooring 3iles $!ereafter referred to as suction 3iles& for floating systems$Surface ell!ead "latform $S"& Floating "roduction Storage :ffloading *essel$F"S:& oil offloading system and riser su33orts& and subsea systems $subsea manifolds&.!is s3ecification assumes t!e suction 3iles ill be designed and installed in normally toslig!tly o*er-consolidated clayey soils.

!e 3rimary ob;ecti*e of t!is document is to 3ro*ide a basis and met!odology for t!edesign of t!e suction 3iles. !is document summari#es t!e design re8uirements ands3ecifies t!e *arious analyses t!at s!all be 3erformed in t!e design and *erification of t!esuction 3iles. !is document ill also ser*e as a reference guide for t!ird 3arty *erificationefforts and classification society re*ie.

!e :


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Suction Pile Design

Specifications

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'ENEAL SPECI(ICATIONSPage $ of #"

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!e design 3rocess s!all com3rise t!e folloing engineering acti*ities?

1. Global si#ing of t!e suction 3ile based on soil strengt! 3ro3erties@

2. Global si#ing of t!e suction 3ile to ensure t!at t!e 3um3-in suction 3ressure isacce3table for t!e a*ailable soil strengt! $i.e. soil 3lug stability c!ec0&@

'. Global si#ing of t!e suction 3ile to ensure t!at t!e 3um3-out 3ressure is acce3table fort!e a*ailable soil strengt! in case t!at anc!or remo*al is necessary@

4. Structural design for ma=imum installed loads and soil reactions including detaileddesign of t!e 3adeye area for t!e local stresses due to t!e mooring line loads and t!e3adeye castings@

5. Structural design for 3um3-in o3eration and if a33licable for 3um3-outA3ull-outo3eration@

6. %esign of a33urtenances and 3ile to3 configuration for installation and for reco*ery.

!e folloing design assum3tions !a*e been ado3ted in de*elo3ing t!ese s3ecifications.!ese assum3tions s!all be !onored by t!e structural designer suction 3ile fabricator andt!e foundation installation contractors in de*elo3ing t!eir res3ecti*e designs.

Flo c!annels ill not occur near t!e 3ile-soil interface

Full frictional resistance can be de*elo3ed along t!e 3ile all re8uiringminimal soil dis3lacement during installation

)e*erse end-bearing can 3otentially be de*elo3ed re8uiring t!at t!e 3ile entert!e soil it! lo dis3lacement of soils $e.g. minimal !ea*e of soil 3lug at t!e mudline&

!e 3ile be!a*es it! res3ect to foundation be!a*ior mec!anics as a rigidbody.

!ese assum3tions collecti*ely result in t!e folloing restrictions in design?

"iles s!all include no internal or e=ternal ring stiffeners

Soil 3lug !ea*e and internal 3ressures ill be monitored to ensure t!at rate ofinstallation for self-eig!t and suction 3enetration occurs at a rate t!at ill not cause3lug !ea*e. )efer to installation s3ecifications.

"iles s!all be!a*e elastically for all design loading conditions.

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2. R$&$,$'*$)

!e %%B $!ull and mooring system& is considered to be a site-s3ecific fi=ed offs!ore installation t!atill be unflagged. %et


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merican elding Society $S&

S %1.1 Structural elding ode Steel

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3. D$&'(%')

3.1. G$'$,!#

nless noted belo terms and acronyms used in t!is s3ecification s!all be inter3reted asdefined in General Glossary S3ecification (M%-/)(-G-S-+121-1++2 or by a standard(nglis! dictionary if not listed in t!e General Glossary S3ecification.

3.2. T$,9)

!e folloing terms s!all be inter3reted in t!is S3ecification as meaning?

a*e Fre8uency )ange - !e range of fre8uencies containing a*e energy. a*efre8uencies are s3ecified as cycles 3er second or radians3er second. It is also used as a s3ecific descri3tion. Fore=am3le a*e fre8uency motions are res3onses it!fre8uencies it!in t!e a*e fre8uency range.

o Fre8uency )ange - !e range of fre8uencies loer t!an t!e a*e fre8uencyrange. It is also used as a s3ecific descri3tion. For e=am3lelo fre8uency motions are res3onses it! fre8uenciesit!in t!e lo fre8uency range.

ut-off Fre8uency - s3ecified fre8uency defining t!e di*ision beteen a*efre8uency and lo fre8uency ranges. ty3ical cut-offfre8uency for t!e %%B global 3erformance analysis is+.+' # $''.' seconds&.

Sea-state - !e en*ironmental conditions $ind a*es and current&e=isting at a gi*en site o*er a finite 3eriod of time.

a*e S3ectrum - statistical descri3tion of regular a*e com3onents gi*ingt!e distribution of energy used to analytically model anocean a*e en*ironment.

ind S3ectrum - statistical descri3tion of ind com3onents gi*ing t!edistribution of energy used to analytically model an oceanind en*ironment.

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%ata S!eet? - data s!eet is a ty3e of re3ort used to facilitate datatransfer beteen disci3lines. %ata s!eets ty3ically contain3articular res3onse summaries to be used as design in3utfor riser structural etc. designs. %etailed tec!nicaldescri3tions of t!e assum3tion models etc. ill bereser*ed for t!e main analysis re3ort.

nc!or "oints - ocations on t!e seabed !ere anc!ors are set.

atenary - !e s!a3e assumed by a mooring line sus3ended beteent!e mooring fairlead and seafloor. If buoys or clum3eig!ts are included t!en a com3ound catenary s!a3eresults.

%i3 one - !is is t!e segment of mooring line beteen touc!don 3oints

at t!e seabed !en t!e line is most loaded and most slac0. Itis t!e segment t!at incurs t!e most abrasion because of cycliccontact it! t!e seabed. Generally a lengt! of c!ain is3ro*ided in t!e di3 #one.

%ynamic Mooringine nalysis - time domain finite element analysis 3rocedure !ere t!e line

tensions due to fairlead a*e fre8uency motions are e=3licitlycom3uted. !is may also be done in fre8uency domain!ic! is fast but in*ol*es sim3lifying assum3tions t!at mayim3act accuracy. It may be done in time domain !ic! islonger more e=3ensi*e but most accurate. "I and lassSocieties recogni#e bot! met!ods.

Mean :ffset - !e amount of !ori#ontal mo*ement of t!e *essel from t!einitial 3osition to its e8uilibrium 3osition !en t!e systemrestoring forces and moments balance mean en*ironmentalforces and moments.

Huasi-Static nalysis - fre8uency domain analysis 3rocedure !ere t!e ma=imummooring line tension is obtained by sim3le !ori#ontaltranslation of t!e fairlead 3oint by t!e 3redicted ma=imumoffset 3osition. ine tensions due to lo fre8uency motions

ill in general be accurately estimated but may besignificantly underestimated for a*e fre8uency motions.

)estoring Force - !e longitudinal and trans*erse forces and moments createdby t!e resultant of all of t!e mooring linesC tensions as t!e

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*essel mo*es in res3onse to en*ironmental loads. restoring force cur*e 3lots restoring force *ersus *esseloffset.

/rea0 Strengt!Safety Factor - !is is t!e ratio of t!e ne catalog brea0 strengt! of t!e

mooring line com3onent to its 3redicted ma=imum tension.!e catalog brea0 strengt! used ill be for t!e nominal linediameter after deducting corrosion and abrasion alloances.

Seabed Slo3e - %efined from t!e bat!ymetry of t!e seafloor and lineari#edit!in t!e touc!don range for eac! anc!or.

l3!a Factor - a measure of 3ile-soil setu3 *ersus time e=3ressed as a3ercentage of t!e fully consolidated 3ile soil frictional

resistance

3.3. A*,%':9)

):B - )emotely :3erated Be!icle

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!e folloing deli*erables s!all be issued by :


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. P#$ L%!)

.1. F#%!(' S:)($9)

.1.1. M%%,'

.1.1.1. E',%'9$'(!##: D$,$ L%!)


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Specifications

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In offs!ore locations !ere e=treme en*ironmental conditions occur on a non-seasonal basis oad onditions 1 and 2 s!all be consolidated and t!e designs!all consider t!e most se*ere en*ironmental loading a33lied at t!e time t!eanc!or lines are attac!ed to t!e !ull.

If it is necessary to commence suction 3ile design or0 3rior to t!e com3letionof dynamic mooring analyses t!en suitably factored 8uasi-static loads may beused for 3reliminary suction 3ile design.

.1.1.2. L%' T$,9 S7)(!'$ L%!)

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.2. S7")$! S:)($9)

!e 3i3eline manifold ill a33ly mainly steady-state loads to t!e anc!or 3iles. !ese loadsinclude com3ression lateral moment and torsion. S!ort-term loads t!at may be a33liedinclude t!ose due to t!ermal e=3ansion and contraction. For t!e subsea manifoldfoundation t!e :


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Suction Pile Design

Specifications

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'ENEAL SPECI(ICATIONSPage &$ of #"

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5. G$%($*6'*!# S7*(%' P#$ D$)'

5.1. S7*(%' P#$ D$)' B!))

5.1.1. F#%!(' S:)($9)

5.1.1.1. D:'!9* M%%,' A'!#:)$)

Final suction 3ile design s!all be based on t!e 3ile loads obtained fromdynamic mooring analysis and t!e folloing load factors and soil resistancefactors?

For Intact Mooring System?

oad Factor K 1.'+

Soil )esistance Factor K+.7+

For :ne-line %amaged Mooring?

oad Factor K 1.2+

Soil )esistance Factor K+.9+

In t!e calculation of suction 3ile a=ial ca3acity $!en sub;ect to ma=imumdynamic loading& 3ile suction may be considered for en*ironmentally deri*edloads suc! as 3ea0 storm loads 3ro*ided t!e 3ile is fitted it! a closed to3and means of closure for *ent o3enings and t!e 3um3 suction fitting are3ro*ided and it can be demonstrated t!at t!e suction ill not degrade o*er t!elife of t!e structure $minimum 25 years&. "ile suction s!all not be consideredfor long duration loads suc! as t!e 3retension load t!e ma=imum anc!or loadat t!e mean offset due to 1++-year metocean e*ents or for loo3 currentloads$if a33licable& unless suitable data are a*ailable for demonstrating t!atsuction can be safely relied u3on.

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5.1.1.2. P,$($')%' L%! A'!#:))

!e 3retension load analysis s!all e*aluate t!e suction 3ile design to minimi#et!e 3otential for long term 3ile dis3lacements due to cree3. !e analysis s!alle*aluate t!e suction 3ile design for t!e condition of t!e *ertical com3onent oft!e 3retension anc!or load resisted by 3ile a=ial s0in friction.

For ma=imum alloable 3retension in t!e anc!or t!e folloing load andresistance factors s!all be used?

=ial oad Factor K 1.'+

=ial Soil Friction )esistance Factor K +.'+

5.1.1.3. S7)(!'$ T$')%' L%! A'!#:)$)


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5.1.2. S7")$! M!'&%#

!e com3ressi*e load analysis s!all e*aluate t!e anc!or 3ile design forade8uate bearing ca3acity. !e analysis s!all consider dead loads - % li*eloads - $e.g. fluid flo and t!ermal e=3ansionAcontraction& and momentsassociated it! bot! loading conditions.

!e folloing load and resistance factors s!all be used?

oad Factors K 1.'%L1.5

=ial Soil )esistance Factor K +.,

5.2. D$)'

5.2.1. G$'$,!#

Suction 3iles are ty3ically used in con;unction it! taut-leg ty3e mooringlines due to t!is 3ile designs ca3ability of it!standing !ori#ontal and*ertical loads. !e suction 3iles s!all be designed to it!stand ma=imumintact and one line damaged mooring loads.

!e design 3rocess s!all com3rise t!e folloing engineering acti*ities?

1. Global si#ing of t!e suction 3ile based on soil strengt! 3ro3erties@

2. Global si#ing of t!e suction 3ile to ensure t!at t!e 3um3-in suction3ressure is acce3table for t!e a*ailable soil strengt! $i.e. soil 3lugstability c!ec0&@

'. Global si#ing of t!e suction 3ile to ensure t!at t!e 3um3-out 3ressure isacce3table for t!e a*ailable soil strengt! in case t!at anc!or remo*al isnecessary.

5.2.2. S7*(%'-I')(!##$ A'*6%, P#$ S>'


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3ro*ide ade8uate ca3acity for t!e mooring line loads $combined lateral anda=ial loading& and soil 3ro3erties in con;unction it! t!e load and soilresistance factors defined in section 6.1.1 and 6.1.2 abo*e. !e:


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5.2.2./. P#$-S%# S$(-7+

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)ooring line

)inimumpenetration

!nstallation tolerancegoverning for lateral

resistance

%eabed

Targetpenetration

) o o r i n g l i n e

) i n i m u mp e n e t r a t i o n

! n s t a l l a t i o n t o l e r a n c eg o v e r n i n g f o r v e r t i c a l

r e s i s t a n c e

% e a b e d

T a r g e tp e n e t r a t i o n

.

( r i e n t a t i o n t o l e r a n c e

) o o r i n g l i n e ..

'. In*estigate t!e influence on 3ile ca3acity of relocating one or more 3iles adistance of 6+m from t!e original design location in directions bot!inboard and outboard relati*e to t!e %%B. alculate re8uired c!angesin 3ile lengt! to satisfy design load c!anges andAor estimated soil*ariability for t!is mo*ement $if soil *ariability is not e=3licit in t!egeotec!nical re3ort modified load and resistance factors s!ould bede*elo3ed in consultation it! :M"&.

4. (stablis! t!e minimum relati*e =-y s3acing of t!e 3iles it!in 3ileclusters s!ould t!e original 3ile configuration need to be modified duringinstallation.

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5.3.1. E9"$9$'(

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t!e ty3e of inc!es used on large anc!or !andling *essels and on t!e strengt!of t!e ire ro3e and s3reader bar used for installation of t!e suction anc!or.

it! regard to reinstallation of t!e 3ile analyses ill be 3erformed todetermine t!e minimum =-y distances t!at t!e 3ile can be reinstalled relati*e tot!e original 3ile location. In t!e calculations t!e folloing 3lug conditionsill be assumed? $1& t!e soil 3lug is e=truded and remains intact !en t!e 3ileis retrie*ed@ and $2& t!e soil 3lug is remo*ed it! t!e 3ile.

5./. G$%($*6'*!# D$)' D$#$,!"#$)

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6. 33endices - ontains details of eac! of t!e sections in t!e main body of t!e re3ort.

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8. S(,7*(7,!# S7*(%' P#$ D$)'

8.1. G$'$,!# D$)' R$?7,$9$'()

8.1.1. F#%!(' S:)($9)

!e suction 3ile structure s!all be designed to it!stand t!e ma=imum loads$and corres3onding soil reactions& a33lied by t!e mooring line t!e ma=imum*acuum re8uired for 3ile embedment and t!e ma=imum internal 3ressurere8uired for 3ile 3um3-out $Sections 5.1 5.' 5.4 and 5.5&.

8.1.2. S7")$! S:)($9)

!e suction 3ile structure s!all be designed to it!stand loads a33lied by t!efolloing? ma=imum o3erational loads trans3ortation lifting loering t!ema=imum *acuum re8uired for 3ile embedment and t!e internal 3ressurere8uired for 3ile 3um3-out $Section 5.1 5.' 5.4 and 5.5& and reco*ery.

8.2. D$)' !' A'!#:))

8.2.1. I'-P#!*$ F'($ E#$9$'( A'!#:))

Stresses in suction 3iles used for the mooring of floating systemss!all bedetermined by detailed s!ell element finite element analysis. Finite elementstresses s!ould be obtained for t!e main body $cylinder& 3ile to3 internalstiffening and 3adeye. Gra*ity and mooring loads $Section 5.+& s!ould beconsidered. !e effect of t!e surrounding soil s!all be accounted for eit!er bya33lying t!e soil reactions to t!e model or as 3art of t!e stiffness model.

%etailed s!ell element finite element analysis is generally not re8uired forsubsea system foundations.

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8.2.2. A##%@!"#$ S(,$))$) !' U)!$ F!*(%,)

!e nominal Bon-Mises $e8ui*alent& stress s!all not e=ceed t!e ma=imum3ermissible stress as calculated belo?

p' (F#

Where)

(' basic usage factorF# ' material #ield strength

!e basic usage factor s!all be +.7 for t!e ma=imum in-3lace loadingcondition and +.6 for normal o3erating trans3ortation lifting loering and

reco*ery

It s!ould be noted t!at t!e 3ermissible stresses are based on t!e fiber stressesfor sim3le beam analyses and t!e membrane or mid-t!ic0ness stresses forfinite element analyses using 3late elements.

For laterally loaded 3lates also e=3osed to in3lane $e.g. membrane& stressest!e surface Bon Mises stress com3uted at t!e middle of t!e 3late field $e.g.miday beteen stiffeners andAor girders& s!all not e=ceed t!e folloing?

p ' *(+ (,-. F#

oe*er t!e nominal elastic stress calculated in t!e middle of t!e 3late field

due to lateral 3ressure acting alone s!all not e=ceed +Fy.

8.2.3. B7*#' C6$*)

!e buc0ling strengt! of t!e 3iles s!all be c!ec0ed in accordance it! t!e%


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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $+ of #"

e)% " Sept% &$* $"""

Ta1le .%& 2 CoefficientT3pe of St4uctu4e

"%$ "%$ 5 5 &%"

&%"

nstiffened flat 3late 3anels 1.1+ 1.1+ 1.1+

Girders beams stiffenerson 3lates and s!ells

1.++ 1.++ 1.++

olumns beam-columns 1.++ 1.+25 +.125 +.9+

S!ells of single cur*ature 1.++ 1.+5+ +.25+ +.7+

S!ells of double cur*ature +.7+ +.74+ +.2++ +.64

/uc0ling c!ec0s for 3iles used to moor floating systems s!all be based on t!eresults of t!e finite element analysis.

8.2./. F!(7$ A'!#:))

Fatigue damage is to be considered for t!e in-3lace condition. !e totalfatigue damage times a safety factor of 1+ s!all be less t!an unity for t!edesign life of t!e 3latform.

Fatigue analysis of suction 3iles used to su33ort subsea systems is re8uiredonly for 3iles sub;ected to significant dynamic loading. nalysis met!odologys!ould follo %


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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $, of #"

e)% " Sept% &$* $"""

reatment of elds to Im3ro*e Fatigue ife

8.2.. M%%,' C6!' P!$:$ C%''$*(%'Mooring c!ain 3adeye connections s!all be designed to satisfy bot! strengt!and fatigue re8uirements.

!e 3adeye s!all be designed for a ma=imum load e8ual to t!e brea0 strengt!of t!e c!ain multi3lied by a load factor of 1.2. !e orientation of t!e designload s!all be t!e calculated orientation 3lus a LA- 5 degree alloance for*ertical misalignment and a LA- 1+ degree alloance for torsionalmisalignment. usage factor of +.7 s!all be a33lied in con;unction it! t!isload.

%esign calculations for 3adeyes s!all include bearing 3ull out s!ear a=ial

bending and combined stress c!ec0s for t!e critical sections of t!e main 3latec!ee0 3late and all eldments.

"late t!ic0ness 3late si#e and 3in !ole diameter s!all be 3ro3ortioned toaccommodate t!e selected s!ac0le it!out e=cessi*e strain to t!e s!ac0le and3in.

!e mooring c!ain 3adeye connection s!all also be analy#ed using a localfinite element model t!at includes t!e 3rimary structural elements framing intot!e 3adeye. !e finite element model s!all be used to *erify strengt! for t!ema=imum design load and to determine !ot s3ot stresses for fatigue analysis.!e finite element analysis s!all be 3erfomed in accordance it! t!e generalguidelines gi*en in Section 5.9 of (M%-(%(-G-


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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $ of #"

e)% " Sept% &$* $"""

8.2.. C#!))&*!(%' %& S(,7*(7,!# S($$#

ll steel in t!e suction 3iles s!all be classified as s!on in t!e table belo.!e design re8uirements for a gi*en structure are a function of t!isclassification.

"rimary structure is defined as t!ose structural elements essential to t!eo*erall integrity of t!e suction 3ile. !e folloing table summari#es t!eclassification suction 3ile com3onents?

T!%!&'(")AT!(&'("A*T("!+,-()#A&*%,(&L



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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $. of #"

e)% " Sept% &$* $"""

Ta1le .%$ 2 Classification of Suction Pile St4uctu4al Steel

Structural

ategory

Item %escri3tion >ieldy3e

Min. >ieldStrengt!

$M3a&

oug!ness )e8uirements

J +.,5N$19mm&

+.,5N$19mm&

2.+N$5+ mm&

2.+N$5+mm&

")IM)> M(M/()S A!roug! t!ic0ness loading

I

II

III

247

'44

412

(


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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $/ of #"

e)% " Sept% &$* $"""

>ield y3e

S3ecified Minimum>ield Strengt!

M3a

$0si&

NT8&9

$


32/33


Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage $0 of #"

e)% " Sept% &$* $"""

1. !e section of t!e 3ile t!at ill be designed to be abo*e t!e mudline including t!e3ile to3 ill be 3ainted a !ig! *isibility yello.

2. !e 3ile ill be mar0ed in +.25 meter increments on t!e side of t!e 3ile in order togauge 3enetration during self embedment and embedment. !e distance from t!e3ile bottom ill be mar0ed numerically e*ery meter in 1A'-meter !ig! numbers.

'. !e 3ile to3 ill be mar0ed it! a 3ile number and lift eig!t.

8.. A++7,($'!'*$)

!e structural design :


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Suction Pile Design

Specifications

EMDC-BE-C-!S-"##$%&""&

'ENEAL SPECI(ICATIONSPage #" of #"

e)% " Sept% &$* $"""

SECTION INTERVENTION

must clear with ()#A&are : (1) Analysis

methdlgy (s!tware and analysis tls)" (#$ata sheet identi!ying lad cases" (%) Piledesign data sheet listing assum&tins !rverticality' &lacement tlerance' rtatin

.0 #ile Loads.1 'loating %ystems

.1.1 )ooring .1.1.1 ,nvironmentally -erived Loads

ean and *set strm lads derived !rmmring analyses shall be a&&rved by()#A&

4.0 Geotechnical %uction #ile -esign 4.2 -esign 4.2.2 %uction !nstalled Anchor #ile %i7ing 4.2.2.1 General

()#A&will &rvide the CONTRACTOR sil

&r&erties !r design &ur&ses

4.0 Geotechnical %uction #ile -esign 4.2 -esign 4.2.2 %uction !nstalled Anchor #ile %i7ing 4.2.2.2 'loating %ystems

+uctin &ile ca&acity analysis methds shallbe a&&rved in advance by ()#A&

4.0 Geotechnical %uction #ile -esign 4.2 -esign 4.2.2 %uction !nstalled Anchor #ile %i7ing 4.2.2. #ile %oil %et8*p

CONTRACTOR shall cn!er with ()#A&

during the devel&ment ! the &ile sil set-u&curves &rir t their a&&licatin t design

4.0 Geotechnical %uction #ile -esign 4.2 -esign 4.2.2 %uction !nstalled Anchor #ile %i7ing 4.2.2. #ile %ensitivity %tudies

,hen checing the e*ect ! shi!ting ./m !rmthe target lcatin' i! sil variability is nte0&licit in the getechnical re&rt' mdiedlad and resistance !actrs shuld be

devel&ed in cnsultatin with ()#A&4.0 Geotechnical %uction #ile -esign 4. Geotechnical -esign -eliverables

CONTRACTOR shall submit dra!t written naldesign re&rt !r review by ()#A&&rir tsubmitting the nal re&rt

3.0 %tructural %uction #ile -esign 3.2 -esign and Analysis 3.2.10 )etocean riteria

$esign cnditins !r the trans&rtatin

analysis will be determined by ()#A&asre2uired n the &r3ect n a case by casebasis

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Suction Pile Spec

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