5.1 common items for piled piers (1) the performance ... · design water depth steel pipe pile...

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PART III FACILITIES, CHAPTER 5 MOORING FACILITIES – 817 – [Technical Note] 5.1 Common Items for Piled Piers (1) The performance verification of piled piers in common may be in accordance with 2.1 Common Items for Quaywalls. (2) The structural types of piled piers include open-type wharves on vertical piles, open-type wharves on coupled raking piles, jacket type piers and strutted frame type pier. (3) An example of the procedure of the performance verification of piled piers is shown in Fig. 5.1.1. (4) Access Bridges In setting the structure and cross-sectional dimensions of access bridges in the performance verification of piled piers, it is necessary to appropriately consider the conditions of use of the concerned piers, in order that the piled pier can be safely and efficiently used. Also, in setting the structure and cross-sectional dimensions of access bridges in the performance verification of piled piers, it is necessary to appropriately consider the amount of relative deformation between the main structure of the piled pier and the earth-retaining section, and also the allowable horizontal displacement of the access bridge. Setting of design conditions Verification of stability of earth-retaining section Verification of pile stresses Verification of bearing capacity of piles Determination of cross-sectional dimensions Verification of structural members (verification of superstructure, etc.) -Setting of size of 1 block -Setting cross-section and layout of piles -Assumption of dimensions of superstructure -Layout of mooring posts, fenders -Assumptions regarding seabed soils Permanent states Permanent states,variable states of Level 1 earthquake ground motion Variable states of the action of ships,surcharges, and Level 1 earthquake ground motion Accidental states of Level 2 earthquake ground motion Verification of amount of deformation from dynamic analysis and damage to piled pier Assumption of cross-sectional dimensions Evaluation of actions including setting seismic coefficient for verification *1 *2 Performance verification Performance verification Verification of slope stability *1: Evaluation of the effect of liquefaction and settlement is not shown on the diagram, so it is necessary to separately into consider. *2: Verification shall be carried out for high earthquake-resistance facilities against the Level 2 earthquake ground motion. Fig. 5.1.1 Example of the Sequence of Performance Verification of a Piled Pier

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  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –817–

    [Technical Note]

    5.1 Common Items for Piled Piers

    (1)Theperformanceverificationofpiledpiersincommonmaybeinaccordancewith2.1 Common Items for Quaywalls.

    (2)Thestructuraltypesofpiledpiersincludeopen-typewharvesonverticalpiles,open-typewharvesoncoupledrakingpiles,jackettypepiersandstruttedframetypepier.

    (3)AnexampleoftheprocedureoftheperformanceverificationofpiledpiersisshowninFig. 5.1.1.

    (4) AccessBridgesInsettingthestructureandcross-sectionaldimensionsofaccessbridgesintheperformanceverificationofpiledpiers,itisnecessarytoappropriatelyconsidertheconditionsofuseoftheconcernedpiers,inorderthatthepiledpiercanbesafelyandefficientlyused.Also,insettingthestructureandcross-sectionaldimensionsofaccessbridgesintheperformanceverificationofpiledpiers,itisnecessarytoappropriatelyconsidertheamountofrelativedeformationbetweenthemainstructureof thepiledpier and theearth-retaining section, andalso theallowablehorizontaldisplacementof theaccessbridge.

    Setting of design conditions

    Verification of stability of earth-retaining section

    Verification of pile stresses

    Verification of bearing capacity of piles

    Determination of cross-sectional dimensions

    Verification of structural members (verification of superstructure, etc.)

    -Setting of size of 1 block-Setting cross-section and layout of piles-Assumption of dimensions of superstructure-Layout of mooring posts, fenders-Assumptions regarding seabed soils

    Permanent states

    Permanent states,variable states ofLevel 1 earthquake ground motion

    Variable states of the action of ships,surcharges, and Level 1 earthquake ground motion

    Accidental states of Level 2 earthquake ground motion

    Verification of amount of deformation fromdynamic analysis and damage to piled pier

    Assumption of cross-sectional dimensions

    Evaluation of actions including settingseismic coefficient for verification

    *1

    *2

    Performance verificationPerformance verification

    Verification of slope stability

    *1: Evaluationoftheeffectofliquefactionandsettlementisnotshownonthediagram,soitisnecessarytoseparatelyintoconsider.*2: Verificationshallbecarriedoutforhighearthquake-resistancefacilitiesagainsttheLevel2earthquakegroundmotion.

    Fig. 5.1.1 Example of the Sequence of Performance Verification of a Piled Pier

  • – 818–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    5.2 Open-type Wharves on Vertical Piles5.2.1 Fundamentals of Performance Verification

    (1)Thefollowingreferstoopen-typewharvesonverticalpilesusingsteelpipepilesorsteelsections,butitmayalsobeappliedtosimilarfacilitiesprovidedthattheirdynamiccharacteristicsaretakenintoaccount.

    (2)Fortheprocedureofperformanceverificationofopen-typewharvesonverticalpiles,itispossibletorefertoFig. 5.1.1of5.1 Common Items for Piled Piers.However,evaluationoftheeffectofliquefactionisnotshowninFig. 5.1.1,soitisnecessarytoappropriatelyinvestigatethepotentialforliquefactionandmeasuresagainstit,(refertoPart II, Chapter 6 Ground Liquefaction).

    (3)In theperformanceverificationofopen-typewharvesonverticalpiles,normally thecross-section is setwithrespecttoactionsotherthanthatofLevel2earthquakegroundmotion,whiletheseismicperformanceisverifiedwithrespecttoLevel2earthquakegroundmotion.ThisisbecauseforverificationofvariablesituationinrespectoftheactionofshipsandLevel1earthquakegroundmotion,theperformanceverificationiscarriedoutbasedontheyieldstressforthesteelpipepiles,butforseismicperformanceverificationofseismic-resistantwithrespecttoLevel2earthquakegroundmotion,averificationmethodthattakestheextentofdamagetothepiledpierintoaccountisused.

    (4)ForthevariablesituationinrespectofLevel1earthquakegroundmotion,itispossibletocarryoutverificationbyobtaining thenaturalperiodsof thepiledpierbasedona frameanalysis, and thencalculating the seismiccoefficientforverificationusingtheobtainednaturalperiodsandtheaccelerationresponsespectrum.However,forhighearthquake-resistancefacilities,verificationmaybecarriedoutusinganappropriatedynamicanalysismethod,suchasnonlinearseismicresponseanalysistakingintoaccountthe3-dimensionaldynamicinteractioneffectbetweenpilesandtheground.Foropen-typewharvesonverticalpilesotherthanhighearthquake-resistancefacilities,itispossibletoomittheverificationoftheaccidentalsituationforLevel2earthquakegroundmotion.

    (5)Anexampleofcross-sectionofanopentypepiledpieronverticalpilesisshowninFig. 5.2.1.

    (6)Whencargohandlingequipment,suchascontainercranes,istobeinstalledonanopen-typewharfonverticalpiles,itispreferabletoinstallitinsuchawaythatallofitsfeetarepositionedoneitherthepile-supportedsectionor earth-retaining section. If, for example,one footof a cargohandlingequipment ispositionedon thepile-supportedsectionandanotherontheearth-retainingsection,theequipmentbecomessusceptibletoadverseeffectsbyunevensettlementandgroundmotions,duetothedifferenceintheresponsecharacteristicsofthetwosections.When it is unavoidable to position one foot on the pile-supported section and another on the earth-retainingsection,sufficientfoundationworksuchasfoundationpilesshouldbeprovidedtopreventunevensettlementduetothesettlementontheearth-retainingsection.Inthiscase,ingeneral,thefixedfootofcargohandlingequipmentsuchasportalcraneshouldnotbeinstalled.Wheninstallingcargohandlingequipment,suchascontainercranes,seismic responseanalysis shouldbeperformed, taking into consideration the coupledoscillationof the cargohandlingequipmentandtheopen-typewharf.

    H.W.L.

    L.W.L.

    Mortar lining

    Steel pipe pile

    Designwater depth Steel pipe pile

    Steel pipe pile

    SuperstructureBollard

    Fender Access bridge

    Backfilling stones

    Rubble forfoundation

    Earth-retaining section

    Fig. 5.2.1 Example of Cross-section of an Open Type wharf on Vertical Piles

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –819–

    5.2.2 Setting of Basic Cross-section

    (1)Thesizeofadeckblock,thedistancesbetweenpiles,andthenumberofpilerowsshallbedeterminedappropriatelyinconsiderationofthefollowing:

    ① apronwidth② locationofsheds③ seabed,especiallyslopestability④ existingrevetments⑤ mattersrelatedtoconstructionworksuchastheconcretecastingcapacity⑥ surcharges,especiallycranespecifications

    (2)Insuchacasethatlargequaycranesforshipsof10,000tonclassaretobeinstalled,pilesareusuallydesignedtobeplacedby5mwith3-4pilerowsinthecross-section.

    (3)The dimensions of the superstructure of open-type wharf shall be determined appropriately considering thefollowing

    ① distancesbetweenpiles,numberofpilerows,andtheshapeanddimensionsofpiles② constructionproblemofshatteringformsandscaffold③ groundconditions④ arrangementofmooringposts⑤ arrangement,shapeanddimensionsoffenders

    (4)AssumptionsregardingtheSeabedCondition

    ① Determinationofgradientofslope

    (a)Whenanearth-retainingstructureisprovidedbehindtheslope,thepositionoftheearth-retainingstructureshouldbeappropriatelydeterminedconsideringthestabilityoftheslope.

    (b)Itisnecessarytoexaminethestabilityofslopewithrespecttocircularslipfailure.Whenanearth-retainingstructureisinstalledbehindtheslope,itispreferablethatthestructureisnotconstructedinfrontoftheslopesurfacefromthetoeoftheslopeattheslantangleindicatedbyequation(5.2.1)(seeFig. 5.2.2).

    (5.2.1)where,

    α :anglebetweentheslopeandthehorizontalsurface(°) φ :angleofshearresistanceofthemainmaterialformingtheslope(°)

    ε =tan-1kh' kh' :apparenthorizontalseismiccoefficient

    For the seismic coefficient for verification for calculating the apparent horizontal seismic coefficient,thevaluecalculated in theanalysisof theearth-retainingsectionmaybeused. Refer to(10)⑥belowforcalculationoftheseismiccoefficientforverificationfortheearth-retainingsection.Inaddition,whentheslopeiscomposedofahardmudstoneorrock,equation(5.2.1)maynotbeapplied.

    Design water depth

    Design gradient of slope

    α=φ−ε

    Fig. 5.2.2 Position of Earth Retaining Structure on the Slope

    ② VirtualGroundSurface

    (a) Incalculationoflateralresistanceandbearingcapacityofpiles,avirtualgroundsurfaceshallbeassumedatanappropriateelevationforeachpile.

    (b)Whentheinclinationoftheslopeisconsiderablysteep,thevirtualgroundsurfaceforeachpiletobeusedinthecalculationoflateralresistanceorbearingcapacitymaybesetatanelevationthatcorrespondsto1/2oftheverticaldistancebetweenthesurfaceoftheslopeatthepileaxisandtheseabedasshownin(Fig. 5.2.3).

  • – 820–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    Virtual ground surface

    Fig. 5.2.3 Virtual Ground Surface

    (5)CoefficientofLateralSubgradeReaction

    ① Inthecalculationofthelateralresistanceofpiles,itispreferabletoobtainthecoefficientoflateralsubgradereactionofthesubsoilthroughlateralloadingtestsofpilesin-situ.Incasethatnotestsareconducted,itmaybeestimatedbymeansofappropriateanalyticalmethodsderivedfromlateralresistancetests.

    ② Therearesomemeasureddataavailableonthecoefficientoflateralsubgradereactionobtainedbythetestsinwhichthelateralloadswereappliedtopilesuptotheyieldpointsasobservedinthecaseofpilesofopen-typewharves. Althoughsomeof thesedatahavebeen related to theN-value, thecoefficientof lateral subgradereactioncannotbeestimatedaccuratelyfromtheN-value.Thus,itispreferabletoestimatethecoefficientbylateralloadingtestsin-situ.

    ③ Whenlateralloadingtestsofpilesarenotcarriedoutduetosmallscaleconstructionworksortimeconstraints,thecoefficientoflateralsubgradereactionofthesubsoilmayunwillinglyusethemeanvalueoftheminimumvalueandcentralvalueobtainedfromlateralresistancetests.WhenusingChang’smethod,equation(5.2.2)maybeutilized andChapter 2, 2.4.5 [4] Estimation of Pile Behavior using Analytical Methods canbereferenced. However, some in-situmeasurementdata indicate that the coefficientvalueof lateral subgradereactionofrubblestonesissmallerthantheestimatebyequation(5.2.2)withChang’smethod.Inthiscaseitisrecommendedtosetthecoefficientoflateralsubgradereactionequalto3.0-4.0N/cm2inChang’smethod.

    (5.5.2)where

    kCH :coefficientofhorizontalsubgradereaction(N/cm3) N :averageN-valueofthegrounddowntoadepthofabout1/β β :referto(6) Virtual Fixed Point

    Thecoefficientoflateralsubgradereactionshowninequation(5.2.2)isastaticcoefficientofsubgradereaction,andmaybeusedwhencalculating thenaturalperiodsofpiledpiersby frameanalysis. There isnotmuchknowledgeregardingthecoefficientofsubgradereactiontobeconsideredwhencarryingouttheverificationofseismicresponseanalysis,hencethereisaprobleminapplyingequation(5.2.2)todynamicanalysis.Thereforeitispreferabletosetthecoefficientequaltoaboutdoublethevalueobtainedfromequation(5.2.2).

    (6)VirtualFixedPointWithrespecttoanopen-typewharfonverticalpiles,thevirtualfixedpointsofthepilesmaybeconsideredtobelocatedatadepthof1/β belowthevirtualgroundsurface.Thevalueofβiscalculatedbyequation(5.2.3).

    (5.2.3)where

    kCH :lateralsubgradereactioncoefficient(N/cm3)calculatedbyequation(5.2.2) D :diameterorwidthofthepile(cm) EI :flexuralrigidityofthepile(N·cm2)

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –821–

    5.2.3 Actions

    (1)For the calculation of the self weight of reinforced concrete superstructures, each part of the dimensions isassumedbasedonthedimensionsofthesuperstructure,andthevolumeiscalculatedonthem.TheselfweightcanbeobtainedbymultiplyingunitweightobtainedfromPart II, Chapter 10, 2 Self weightbythevolume.Inaddition,forthecalculationoftheselfweightofreinforcedconcretesuperstructures,21kNper1.0m2ofdeckareaofthesuperstructureofthepiledpiermaybeassumed.

    (2)Atthesiteexpectedtobesubjecttowaves,thefollowingitemsshouldbeexaminedregardingwaveupliftonthesuperstructureofpiledpierandtheaccessbridge.

    ① Stabilityoftheaccessbridgesandpullingresistanceofpilesagainstuplift.

    ②Memberstrengthofthesuperstructuresandaccessbridgesagainstuplift. Foruplift,refertoPart II, Chapter 2, 4.7.4(1) Uplift Acting on Horizontal Plates near the Water Surface.

    (3)ThestaticloadsmaybedeterminedinaccordancewithPart II, Chapter 10, 3.1 Static Load.Theearthquakeinertiaforcesduetostaticloadsmaynormallybeconsideredtoactontheuppersurfaceofthedeckslab.However,whenthecenterofgravityofthestaticloadsislocatedatanespeciallyhighelevation,itisimportanttotaketheheightofthecenterofgravityasthepointofapplicationofthehorizontalforce.

    (4)LiveloadsshouldbedeterminedinaccordancewithPart II, Chapter 10, 3.2 Live Load.Theseismicforceduetoarailmountedcraneshouldbecalculatedbymultiplyingitsselfweightbytheseismiccoefficientforverification,andtheforcecanbeconsideredtobetransmittedfromthewheelsofthecranetothepile-supportedsection.Itisalsonecessarytocarryoutseismicresponseanalysisconsideringthecoupledoscillationsofthecargohandlingequipmentandtheopen-typewharf(refertoPart III, Chapter 7 Cargo Handling Facilities, 2.2 Fundamentals of Performance Verification).Inthiscase,groundmotionshallbeappliedintheformofatime-seriesseismicwaveprofile.ThewindloadactingoncranemaybedeterminedinaccordancewithPart II, Chapter 2, 2.3 Wind Pressure.

    (5)ThefenderreactionforcecanbecalculatedinaccordancewithPart II, Chapter 8, 2.2 Actions Caused by Ship Berthing andPart II, Chapter 8, 2.3 Actions Caused by Ship Motions and 9.2 Fender Equipment.

    (6)The tractive force of vessels can be determined in accordancewithPart II, Chapter 8, 2.4 Actions due to Traction by Ships.Inmanycasesonebollardisinstalledtoonedeckblock.

    (7)Whenrubberfendersareinstalledasadamperonanordinarylargewharfwithaunitdeckblockof20to30minlength,acommonpracticeistoprovidetworubberfendersononeblock.Inmanycases,fenderintervalsof8to13mareused.Theberthingbehaviorofvarioussizesofshipshasbeenexaminedbyinstalling1.5-meter-longrubberfendersonanordinarylargewharf.Theresultsofexaminationhasrevealedthatitisappropriateto calculate the berthing force on the assumption that the ship’s berthing energy is absorbed by one fender.Therefore,thereactionforcemaybasicallybecalculatedontheassumptionthattheberthingenergyisabsorbedbyonefenderwhenusingrubberfendersasadamper.However,thisdoesnotapplywhenfendersareinstalledcontinuouslyalongthefacelineofawharf.

    (8) Theberthingenergy is alsoabsorbedby thedisplacementof themain structureof thepier. However, it is acommonpracticenot to take this into considerationbecause inmanycases the energyabsorbedby themainstructureofthepieraccountsforlessthan10%ofthetotalberthingenergy.

    (9)Fig. 5.2.4 showsanexampleof thedisplacement-energycurveandthedisplacement-reactionforcecurveofarubberfender. IfasinglefenderabsorbsaberthingenergyofE1,thecorrespondingfenderdeformationδ1isobtained.Then,usingtheothercurve,thecorrespondingreactionforceactingonthepierisobtainedasH1(δ1→C→H1).However,iffendersareinstalledtooclosetoeachotherandtheberthingenergyisabsorbedbytwofenders,theberthingenergyactingononefenderbecomesE2=E1/2andthecorrespondingfenderdeformationbecomesδ2. Ascanbeobtainedfromthefigure(δ2→D→H2), thereactionforceactingonthepierinthetwofendercaseisalmostthesameasthatgeneratedinthesinglefendercasebecauseofthecharacteristicsofrubberfender.Thusthehorizontalreactionforceactingonthepierbecomes2H2≒2H1,whichmeansthatthehorizontalforcetobeusedintheperformanceverificationbecomestwofold.Whenusingfendersthathavesuchcharacteristics, therefore, it ispreferable togivecarefulconsideration to thisbehaviorof reactionforce in theperformanceverificationandthedeterminationofthelocatingoffenders.

  • – 822–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    H1 H2

    E1

    E2

    D C

    A

    B

    δ2 δ1

    Displacement-reaction force curve

    Displacement-absorbedenergy curve

    Energy orreaction force

    Displacement

    Fig. 5.2.4 Rubber Fender Characteristics Curve

    (10)GroundMotionusedinPerformanceVerificationofSeismic-resistant① Groundmotionusedinperformanceverificationofseismic-resistantissetconsideringtheeffectofthesurface

    stratausingagroundseismicresponseanalysis.Itisnecessarytouseaseismicresponseanalysiscodecapableofappropriatelyevaluatingtheamplificationofgroundmotionsinsoftground(refertoANNEX 4, 1 Seismic Response Analysis of Local Soil Deposit).

    ② Usingaone-dimensionalseismicresponseanalysisasdescribedinANNEX 4, 1 Seismic Response Analysis of Local Soil Deposit,theaccelerationtimehistoryataposition1/β belowthevirtualgroundsurfaceiscalculatedwiththeaccelerationtimehistoryofthegroundmotionsetattheseismicbedrockastheinputgroundmotion.Whencalculatingtheaccelerationtimehistory,theaveragedepthofthe1/β groundpointforeachpilemaybetaken,asshowninFig. 5.2.5.Fromtheaccelerationresponsespectrumobtainedinthisway,theresponseaccelerations corresponding to the natural periods of the piled pier are calculated, and the value obtainedbydividing this by thegravitational acceleration canbe regarded as the characteristic valueof the seismiccoefficientforverification.Adampingfactorof0.2maybeusedwhencalculatingtheaccelerationresponsespectrum.AnexampleofatypicalprocedureforsettingtheseismiccoefficientforverificationisshowninFig. 5.2.6.Whenverifyingtheseismicperformanceofearth-retainingpartsusingtheseismiccoefficientmethod,thestructuralcharacteristicsaredifferentfromthoseofthepiledpier,sotheseismiccoefficientindicatedheremaynotbeused.Forthecalculationoftheseismiccoefficientforverificationforearth-retainingparts,referto⑥below.

    Virtual ground surface

    Position for calculation of acceleration time history

    1/β

    Fig. 5.2.5 Positions for Calculation of Earthquake Ground Motions

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –823–

    Setting of cross-section for performance verificatio

    Setting of soil conditions

    Setting of input seismic motion at engineering bedrock

    One-dimensional seismic response analysis

    Calculation of response acceleration timehistory at 1/β below virtual ground surface

    Calculation of acceleration response spectrum

    Setting of characteristic value of seismic coefficient for verification

    Calculation of natural periods of piled pierFrame analysisCalculation of spring constants of piled pierCalculate natural period

    Fig. 5.2.6 Typical Procedure for Setting of Seismic Coefficient for Verification

    ③ DesignvalueofseismiccoefficientforverificationForvariablesituationsunderLevel1earthquakegroundmotion,theminimumofthedesignvalueofseismiccoefficientforverificationis0.05,andthemaximumis0.25. However,whenthecharacteristicvalueof theseismiccoefficientforverificationexceeds0.25,thisvaluedoesnotapply,andthecharacteristicvaluecanbeadoptedas thedesignvalueofseismiccoefficientforverification. Insummary, thedesignvalueofseismiccoefficientforverificationisasfollows.

    (5.2.4)where,

    khd :designvalueofseismiccoefficientforverification khk :characteristicvalueoftheseismiccoefficientforverification

    ④ Thenaturalperiodsofthepiledpiermaybecalculatedusingaframeanalysis.Iftherelationshipbetweenthedisplacementandloadisobtainedfromtheframeanalysis,asshowninFig. 5.2.7,whenminuteloadsareactingonthepiledpier,thespringconstantsofthepiledpiercanbesetandthenaturalperiodscanbeobtainedfromequation(5.2.5). Thegroundspringconstantsusedin theframeanalysismaybecalculatedusingequation(5.2.2).

    (5.2.5)

    where, Ts :naturalperiodofpiledpier(s) W :selfweightandstaticloadduringanearthquakebornebyonerowofpilegroup(kN) g :gravitationalacceleration(m/s2) K :springconstantofthepiledpier(kN/m)

  • – 824–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    tan-1K

    Displacementδtan-1K

    LoadP

    Coefficient of lateral subgrade reactioncan be obtained from equation (5.2.2)

    Fig. 5.2.7 Relationship between Load and Displacement from Frame Analysis

    ⑤ Thenaturalperiodofthepiledpierobtainedfromthespringconstantsofthepiledpierbyframeanalysisusuallyinvolvessomeamountoferrors.Therefore,ifthevalueintheaccelerationresponsespectrumcorrespondingtothenaturalperiodisalocalminimum,theseismiccoefficientforverificationcouldbeunderestimated,andthisshouldnotbeappliedasitis.Inaddition,asindicatedin5.2.5 Performance Verification of Structural Members,repeatedverificationforthevariablesituationunderLevel1earthquakegroundmotionisneeded.Therefore,itispreferablethatthespectralvaluebedeterminedtocalculatetheseismiccoefficientforverificationwithacertainrangeofnaturalperiods.Thus,thenumberofrepetitionsoftheperformanceverificationmaybereduced.However,thisdoesnotdenytheimportanceofavoidingalocalmaximumintheaccelerationresponsespectrumcausedbythesiteeffects.Inthecasethatthenaturalperiodofthepiledpiercorrespondstoalocalmaximumintheaccelerationresponsespectrum,itisverylikelythatthecross-sectionwillnotbeoptimumfromtheviewpointofseismicresistanceperformanceandcost.Itisnecessarytopayattentiontothispointforsettingthecross-sectionforverification.

    Ts T [s]

    αmax

    Width of the natural frequencies to be considered

    αmax: Maximum value of acceleration used to determine the seismic coefficient for verificationTs: Natural period of the piled pier calculated by frame analysis

    Fig. 5.2.8 Consideration of Natural Period in Acceleration Response Spectrum

    ⑥ Seismic coefficient for verification used in performance verification of seismic-resistant of earth-retainingsections

    (a) Generalperformance verification of seismic-resistant of earth-retaining sections can be carried out by directlyevaluatingthedeformationoftheearth-retainingsectionusingadetailedmethodsuchasnon-lineareffectivestressanalysis.Butsimplemethodssuchastheseismiccoefficientmethodcanbealsoused.Inthiscase,itisnecessarytoappropriatelysettheseismiccoefficientforverificationusedintheperformanceverificationcorrespondingtotheamountofdeformationofthefacility,consideringtheeffectofthefrequencycharacteristicsof the groundmotion and the duration. The normal procedure of calculating the seismic coefficient forverificationisasshowninFig. 5.2.9.Forthecalculationoftheseismiccoefficientforverificationofearth-retaining sections of gravity-type, basically refer to 2.2.2 Actions, prepared for gravity-type quaywalls.However,settingthefiltertakingintoconsiderationthefrequencycharacteristicsasshownbythethicklinesisdifferentfromgravity-typequaywalls,andthispointshouldbecarefullyreflectedintheanalysis.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –825–

    Acceleration time history at engineering bedrock Setting of ground conditions

    Setting of filter taking into considerationfrequency characteristics

    Evaluation of cohesive soil ground

    Setting of reduction ratio

    Calculation of square root of sumof squares of time history

    Calculation of reduction ratio p

    One-dimensional seismic response analysis

    Maximum value of ground surface accelerationtime history taking into consideration

    frequency dependenceαf

    Calculation of maximum value ofcorrected acceleration αc

    Calculation of characteristic value ofseismic coefficient for verification

    Setting of allowable amount of deformation Da

    Acceleration time history at ground surface

    Consideration of frequency dependence using filter processing

    Consideration of the effect of duration of seismic motion with the reduction ratio (αf × p)

    Calculation of initial natural periods of background andfoundations underneath wall structure (see (c)2))

    Setting of filter (see (c)1))

    Fig. 5.2.9 Example of Procedure for Calculating Seismic Coefficient for Verification

    (b) For thebasicflowandpoints tobenoticed incalculating the seismiccoefficient forverificationofearth-retainingsectionsofgravity-typestructures,2.2.2, Actionsforgravity-typequaywallsmaybereferredto.However,itisnecessarytoconsidertheeffectonthedeformationoftheearth-retainingsectioninfluencedbytheslopesatthefrontoftheearth-retainingsectionanddeeprubblemound.Andthussettingofthefilterconsideringthefrequencycharacteristicsshallbedonebythecalculationmethoddescribedbelow.

    (c) Settingofthefilterconsideringthefrequencycharacteristics

    1) SettingofthefilterThefilterobtainedfromequation(2.2.1)of2.2.2 Actionsforgravity-typequaywallsmaybeusedasthefilter inconsiderationof the frequencycharacteristicsof thegroundmotionused inverificationof theearth-retainingsectionofgravitystructures.However,asshowninFig. 5.2.10,theheightfromthevirtualgroundsurfacetothetopoftheearth-retainingsectionmaybesubstitutedforthewallheightH.Thevalueofbmaybesetastherangeofvaluesindicatedbyequation(5.2.6)usingtheheightHfromthevirtualgroundsurfacetothetopoftheearth-retainingsection.

    (5.2.6)

    where, H :Heightfromthevirtualgroundsurfacetothetopoftheearth-retainingsection(m)

  • – 826–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    2) CalculationofthenaturalperiodofthebackgroundsoilsandsoilsunderneaththewallstructureThemethod of calculation of the initial natural periodTb of the background soils used in setting thefrequencyfilterthattakesintoconsiderationthegroundmotionoftheearth-retainingsectionofgravity-type structuresmay be the same as themethod for gravity-type quaywalls. Also, the initial naturalperiodTuofthesoilsunderneaththewallstructuremaybecalculatedbyevaluatingthesectionfromthevirtualgroundsurfaceincludingrubblemounddowntotheseismicbedrockasaground,andignoringthegroundfromthevirtualgroundsurfaceuptothebottomofthewallstructure.Inthecaseofgravity-typequaywalls,theTuusedinsettingthefilterisevaluatedreplacingthematerialpropertiesoftheoriginalgroundwith thematerialpropertiesof the rubblemound. However,whencalculating theTuofearth-retainingsectionofgravity-typestructures,thismaynotbeapplied,soitisnecessarytobecarefulaboutthis.Inotherwords,TbandTushouldbecalculatedatthepositionsshowninFig. 5.2.10.

    Ground for calculating TbGround for calculating Tu

    H

    Ground surface

    H

    Crown of earth-retaining section

    BackfillingstonesBackfillingstones

    Ground above virtual groundsurface not considered

    Bottom surface of wallBottom surface of wall

    Engineering bedrock

    Rubble stones

    In-situ soils Evaluate as in-situ soilsVirtual groundsurface

    Evaluate as rubble moundwithout changing materialproperties

    Fig. 5.2.10 Ground Calculation of Natural Periods

    5.2.4 Performance Verification

    (1) Itemstobeconsideredintheperformanceverificationofopen-typewharvesonverticalpilesIntheperformanceverificationofopen-typewharvesonverticalpiles,thenecessaryitemsamongthefollowingitemsshallbeappropriatelyinvestigatedandsetasnecessary.

    ① Thecross-sectionalforcesinthesuperstructure(Variablesituations:actionofships,Level1earthquakegroundmotion,surchargeandactionofwaves,accidentalsituations:Level2earthquakegroundmotion)

    ② Fatiguefailureofthesuperstructure(Variablesituations:repeatedactionsofsurcharge)

    ③ Stresses in piles (Variable situations: action of ships, Level 1 earthquake ground motion and surcharge,Accidentalsituation:Level2earthquakegroundmotion)

    ④ Bearingcapacityofpiles(Variablesituations:actionofships,Level1earthquakegroundmotion,surchargeandactionofwaves,accidentalsituations:Level2earthquakegroundmotion)

    ⑤ Deformation(accidentalsituations:Level2earthquakegroundmotion)PerformanceverificationunderLevel2earthquakegroundmotionshallbeinaccordancewith(11) Verification of Level 2 Earthquake Ground Motions with a Dynamic Analysis Method.Forthecross-sectionalforcesinthesuperstructureandfatiguefailure,referto5.2.5 Performance Verification of Structural Members.

    (2)Intheperformanceverificationofthepiledpiersectionofopen-typewharvesonverticalpilesasdescribedbelow,noloadtransmissionisconsideredfromtheearth-retainingsectiontothewharves.Apiledpierisaveryflexiblestructureifaffectedbydeformationoftheground,hence,piledpiersectionshallbestructurallyindependentofearth-retainingsection.However,inthecasewherethecross-sectionaldimensionsaresuchthatitisnotpossibletoeliminatetheeffectfromtheearth-retainingsection,becauseofphysicalrestrictionsduetogroundcondition,itisnecessarytocarryouttheverificationusingamethodconsideringtheinteractionbetweentheearth-retainingsectionandthepiledpiersection.7)

    (3)IntheperformanceverificationforLevel1earthquakegroundmotion,theseismiccoefficientforverificationiscalculatedfromtheaccelerationresponsespectrumvaluescorrespondingtothenaturalperiodsofthepiledpier,thus,whenthedimensionsofthepilesarenotdetermined,itisnotpossibletodeterminethenaturalperiodsofthe

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –827–

    piledpiereither.Therefore,thedimensionsofthepilesareassumed,andtheseismiccoefficientforverificationiscalculatedfromtheaccelerationresponsespectrumcorrespondingtothenaturalperiods,thentheverificationiscarriedout.Iftheperformancerequirementsarenotsatisfied,thepiledimensionsarechanged,andthesamecalculationneedstoberepeated.

    (4)Performanceverificationofthedeformationmaybecarriedoutbysettinganappropriatelimitingvaluetakingintoconsiderationthedynamicdeformationofthepiledpier.Forexample,theamountofdeformationtoensurethattheaccessbridgedoesnotfalldownmaybetakenasthelimitingvalue.Inthatcase,itisappropriatetousetheresponsedisplacementconsideringthedynamicaction,suchasthedisplacementresponsespectrum,andnotthedisplacementconsideringthestaticaction.

    (5)Performanceverification for stresses in thepilesunderdesignsituation forother thanaccidental situations inrespectofLevel2earthquakegroundmotion

    ① Verificationofthestressesoccurringinthepilesofapiledpiermaybecarriedoutusingequation(5.2.7).Inthefollowingequations,thesymbolγisthepartialfactorcorrespondingtothesuffix,wherethesuffixesdandkindicatethedesignvalueandcharacteristicvaluerespectively.

    (a) When the axial forces are tensile

    (b) When the axial forces are compressive (5.2.7)

    where, σt,σc :tensilestressduetoaxialtensileforcesactingonthecross-section,andcompressivestressdue

    toaxialcompressiveforces,respectively(N/mm2) σbt,σbc :maximumtensilestressandmaximumcompressivestressduetotheflexuralmomentactingon

    thecross-section,respectively(N/mm2) σty,σcy :tensileyieldstressandaxialcompressiveyieldstressfortheweakaxis,respectively(N/mm2)σby :bendingcompressiveyieldstress(N/mm2)

    Thedesignvaluesintheequationsmaybecalculatedfromequation(5.2.8).ThevaluesshowninTable 5.2.2maybeusedasthepartialfactorsintheequations.

    (5.2.8)where,

    A :cross-sectionalareaofpiles(mm2) P :axialforceonpile(N) Z :sectionmodulusofpiles(mm3) M :flexuralmomentofpiles(N·mm)

    ② Fortheyieldstressofpiles,refertoPart II, Chapter 11, 2 Steel.TheaxialcompressiveyieldstressmaybecalculatedfromtheequationinTable 5.2.1.

  • – 828–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    Table 5.2.1 Axial Compressive Yield Stresses (N/mm2)

    SKK400SHK400SHK400MSKY400

    SKK490SHK490MSKY490

    a)When 235

    b)When

    c)When

    a)When 315

    b)When

    c)When

    :Effectivebucklinglengthofmember(cm),r:Radiusofgyrationofmembergrosscross-section(cm)

    ③ Thedesignvaluesofcross-sectional forceson thepilescanbecalculated bymultiplying thecharacteristicvaluesofparameterssuchasthecoefficientofsubgradereaction,theactioninthehorizontaldirection,andotherprobabilisticvariablesbythepartialfactors.

    ④ Itispreferabletocalculatetheflexuralmomentsonthepilesforthedirectionbothnormalandparalleltothefacelineofthewharf.AsintheexampleshowninFig. 5.2.1,ifthegroundsurfaceunderthefloorslabofthepiledpierhasaslopingsurface,itisoftenthecasethattheflexuralmomentsinthefrontmostrowofpilesaremaximizedwhenthegroundmotionactsinthedirectionparalleltothefaceline.

    ⑤When it is considerednecessary toexamine the rotationof thepiledpierunitwhenevaluating theactions,theverificationshouldtakethisintoconsideration.Inthiscasethedistributionofforcesoneachpilemaybeevaluatedasdescribedbelow.

    (a)WhenthesymmetryaxisofthepiledpierunitisperpendiculartothefacelineofthewharfandthedirectionofactionofthehorizontalforceisparalleltothesymmetryaxisasshowninFig. 5.2.11,thehorizontalforcemaybecalculatedbyequation(5.2.9).

    (5.2.9)where

    Hi :horizontalforceonpile(kN) KHi :horizontalspringconstantofpile(kN/m)

    hi :verticaldistancebetweenthepileheadandthevirtualgroundsurface(m) βi :inverseofthedistancebetweenthevirtualgroundsurfaceandthevirtualfixedpointofpile

    (m-1) EIi :flexuralrigidityofpile(kN·m2) H :horizontalforceactingontheunit(kN) e :distancebetweentheblock’ssymmetryaxisandthehorizontalforce(m) xi :distancebetweentheunit’ssymmetryaxisandeachpile(m)

    Thesubscriptireferstothei-thpile.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –829–

    hi

    H xixi

    hihi

    βi11

    hi

    e

    Center of gravityof the pile groupFa

    ce li

    neSymmetry ax

    i-th pile

    Fig. 5.2.11 Distance between the Center of Gravity of the Pile Group and Individual Piles

    (b)Therowofpilesbearingthemaximumtotalhorizontallydistributedforcesissubjecttotheverification.

    (c)WhenobtainingKHi, it isnecessary toappropriatelyset thecoefficientofsubgrade reaction in the lateraldirectionoftheground,andcalculateβ.

    ⑥ ApartfromaccidentalsituationsinrespectofLevel2earthquakegroundmotion,basicallytheperformanceisprescribedbyyieldingoftheedgeofthepilehead.However,thepiledpierischaracterizedwithstructuralrobustness,whichmeansthecapacityofstructuremaynotbefatallydamagedbylocalfailurecausedbygroundmotions,totheextentthattheoriginalfunctionofthestructureislost.Thereliabilityindexforyieldingoftheedgeofthepilewithinthegroundisreportedabout2.0–2.7largerthanthatofthepilehead.8)

    (6)PerformanceverificationofthebearingcapacityinpilesunderdesignsituationsotherthanaccidentalsituationsinrespectofLevel2earthquakegroundmotion

    ① VerificationofthebearingcapacityofpilesinpiledpierscanbecarriedoutappropriatelyinaccordancewithChapter 2, 2.4.3 Static Maximum Axial Pushing Resistance of Piles Foundations,andChapter 2, 2.4.4 Static Maximum Pulling Resistance of Piles Foundations,correspondingtothegroundcharacteristicsandananalysismethodforpilelateralresistance.Inthiscase,forcalculatingthebearingcapacityofpilesonaslopingsurface,thesoilstratabelowthevirtualgroundsurfacecanbeconsideredastheeffectivebearingstrata.

    ② Regardingthevirtualgroundsurface,referto5.2.2 Setting the Basic Cross-section.

    (7)PartialfactorsunderthedesignsituationsotherthanaccidentalsituationsinrespectofLevel2earthquakegroundmotion

    ① Regardingpartialfactorsforstressesoccurringinthepilesofopen-typewharvesonverticalpilesandpartialfactorsforthebearingcapacityofpiles,refertoTable 5.2.2.Thetargetreliabilityindicesandtargetfailureprobabilitiesforstressesinpilesshownin1)and4)ofTable 5.2.2meanthevaluesforedgeyieldingofthepileheadofeachsinglepileinthepiledpier.Inthetable,forthevariablesituationsinrespectoftheactionofships,thereliabilityindexis4.1(failureprobabilityof2.3×10-5),beingbasedontheaveragelevelofsafetyintheconventionaldesignmethods.Whentheexpectedtotalcostrepresentedbythesumoftheinitialcostandtheexpectedvalueof therestorationcostduetofailure is takenintoconsideration, thereliability indexthatminimizes theexpected totalcost is3.2 (failureprobabilityof9.1×10-4) forhighearthquake-resistancefacilities,and2.9(failureprobabilityof1.9×10-3)forotherpiledpiers.9)Ifherethelevelofsafetyisevaluatedfromreliability theorybasedonminimizationof theexpected totalcost, thepartial factorsareasshowninTable 5.2.2 1).9) Concerningthevariablesituations inrespectofLevel1earthquakegroundmotionshownintheTable 5.5.2 (4), theaveragelevelofsafetyofapiledpier inaccordancewiththeconventionaldesignmethodsisevaluatedandshown.Besidestheabove,thepartialfactorsofTable 5.2.2aredefinedtakingintoconsiderationthesettingsbasedontheconventionaldesignmethods.

  • – 830–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    Table 5.2.2 Standard Partial Factors(1) Variable situations in respect of the action of ships

    (ship berthing, traction by ships), Variable situations in respect of surcharge (during operation)(a) When SKK400 is used

    Highearthquake-resistancefacility

    TargetreliabilityindexβT 3.2

    TargetfailureprobabilityPfT 9.1×10-4

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.719 1.260 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.60 0.257 1.333 0.76 Lognormal

    γPH Horizontalforces 1.35 -0.645 0.870 0.25 Normal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Otherthanhighearthquake-resistancefacilities

    TargetreliabilityindexβT 2.9

    TargetfailureprobabilityPfT 1.9×10-3

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.719 1.260 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.60 0.257 1.333 0.76 Lognormal

    γPH Horizontalforces 1.30 -0.645 0.870 0.25 Normal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Allopen-typewharvesonverticalpiles

    γ α µ/Xk V

    Bearingcapacity

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpiles 0.33 - - -

    Pushingpiles 0.40 - - -

    ※1:α:Sensitivityfactor,µ/Xk:Deviationofaveragevalue(averagevalue/characteristicvalue),V:coefficientofvariation.※2: Horizontal forces include fender reaction forces (during ship berthing), tractive forces (during traction), and crane horizontal forces

    (duringoperationofthecrane).※3:Thedesignvalueofaxialforcesinpilesusedintheverificationofbearingcapacitycanbeobtainedfromtheverificationofstressesin

    piles.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –831–

    Table 5.2.2 Standard Partial Factors(1) Variable situations in respect of the action of ships

    (ship berthing, traction by ships), Variable situations in respect of surcharge (during operation)(b) When SKK490 is used

    Highearthquake-resistancefacility

    TargetreliabilityindexβT 3.2

    TargetfailureprobabilityPfT 9.1×10-4

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 0.95 0.719 1.196 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.60 0.257 1.333 0.76 Lognormal

    γPH Horizontalforces 1.35 -0.645 0.870 0.25 Normal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Otherthanhighearthquake-resistancefacilities

    TargetreliabilityindexβT 2.9

    TargetfailureprobabilityPfT 1.9×10-3

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 0.95 0.719 1.196 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.60 0.257 1.333 0.76 Lognormal

    γPH Horizontalforces 1.30 -0.645 0.870 0.25 Normal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Allopen-typewharvesonverticalpiles

    γ α µ/Xk V

    Bearingcapacity

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpiles 0.33 - - -

    Pushingpiles 0.40 - - -

    ※1:α:Sensitivityfactor,µ/Xk:Deviationofaveragevalue(averagevalue/characteristicvalue),V:.Coefficientofvariation.※2: Horizontalforcesincludefenderreactionforces(duringtheshipberthing),tractiveforces(duringtraction),andcranehorizontalforces

    (duringoperationofthecrane).※3:Thedesignvalueofaxialforcesinpilesusedinverificationofbearingcapacitycanbeobtainedfromtheverificationofstressesinpiles.

  • – 832–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    (2) Variable situations in respect of surcharges (during strong winds)

    Allfacilities

    γ α µ/Xk V

    Pilestress

    γσy Steelyieldstrength 1.00 - - -

    γkCH Coefficientofsubgradereaction 1.00 - - -

    γPHHorizontalforces 1.00 - - -

    γq Surcharges 1.00 - - -

    γa Structuralanalysiscoefficient 1.12 - - -

    Bearingcapacity

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpiles 0.40 - - -Pushing:endbearingpiles 0.66 - - -

    Pushing:frictionpiles 0.50 - - -

    ※1:α:Sensitivityfactor,µ/Xk:Deviationofaveragevalue(averagevalue/characteristicvalue),V:coefficientofvariation.※2:Thedesignvalueofaxialforcesinpilesusedintheverificationofbearingcapacitycanbeobtainedfromtheverificationofstressesin

    piles.

    Table 5.2.2 Standard Partial Factors(3) Variable situations in respect of the action of waves

    Allfacilities

    γ α µ/Xk V

    Bearingcapacity

    γP Axialforcesinpiles 1.00 - - -

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpiles 0.40 - - -Pushing:endbearingpiles 0.66 - - -

    Pushing:frictionpiles 0.50 - - -

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –833–

    (4) Variable situations in respect of Level 1 earthquake ground motion

    (a) When SKK400 is usedHighearthquake-resistancefacility(specially

    designated)

    TargetreliabilityindexβT 3.65

    TargetfailureprobabilityPfT 1.3×10-4

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.423 1.260 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.66 0.194 1.333 0.76 Lognormal

    γkh Horizontalforces 1.68 -0.885 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Highearthquake-resistancefacility(standard)

    TargetreliabilityindexβT 2.67

    TargetfailureprobabilityPfT 3.8×10-3

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.443 1.260 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.72 0.215 1.333 0.76 Lognormal

    γkh Horizontalforces 1.36 -0.870 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Otherthanhighearthquake-resistancefacilities

    TargetreliabilityindexβT 2.19

    TargetfailureprobabilityPfT 1.4×10-2

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.455 1.260 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.80 0.195 1.333 0.76 Lognormal

    γkh Horizontalforces 1.23 -0.869 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Allopen-typewharvesonverticalpiles

    γ α µ/Xk V

    Bearingcapacity

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpile 0.40 - - -Pushing:endbearingpile 0.66 - - -

    Pushing:frictionpile 0.50 - - -

    ※1:α:Sensitivityfactor,µ/Xk:Deviationofaveragevalue(averagevalue/characteristicvalue),V:coefficientofvariation.※2:Thedesignvalueofaxialforcesinpilesusedintheverificationofbearingcapacitycanbeobtainedfromtheverificationofstressesin

    piles.

  • – 834–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    Table 5.2.2 Standard Partial Factors

    (4) Variable situations in respect of Level 1 earthquake ground motion (b) When SKK490 is used

    Highearthquake-resistancefacility(speciallydesignated)

    TargetreliabilityindexβT 3.65

    TargetfailureprobabilityPfT 1.3×10-4

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.423 1.196 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.66 0.194 1.333 0.76 Lognormal

    γkh Horizontalforces 1.77 -0.885 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Highearthquake-resistancefacility(standard)

    TargetreliabilityindexβT 2.67

    TargetfailureprobabilityPfT 3.8×10-3

    γ α µ/Xk VProbabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.443 1.196 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.72 0.215 1.333 0.76 Lognormal

    γkh Horizontalforces 1.43 -0.870 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Otherthanhighearthquake-resistancefacilities

    TargetreliabilityindexβT 2.19

    TargetfailureprobabilityPfT 1.4×10-2

    γ α µ/Xk V Probabilitydistribution

    Pilestress

    γσy Steelyieldstrength 1.00 0.455 1.196 0.08 Normal

    γkCH Coefficientofsubgradereaction 0.80 0.195 1.333 0.76 Lognormal

    γkh Horizontalforces 1.30 -0.869 1.000 0.20 Lognormal

    γq Surcharges 1.00 - - - -

    γa Structuralanalysiscoefficient 1.00 - - - -

    Allopen-typewharvesonverticalpiles

    γ α µ/Xk V

    Bearingcapacity

    γc’ Cohesion 1.00 - - -

    γN N-value 1.00 - - -

    γaStructuralanalysiscoefficient

    Pullingpile 0.40 - - -Pushing:endbearingpile 0.66 - - -

    Pushing:frictionpile 0.50 - - -

    ※1:α:Sensitivityfactor,µ/Xk:Deviationofaveragevalue(averagevalue/characteristicvalue),V:coefficientofvariation.※2:Thedesignvalueofaxialforcesinpilesusedintheverificationofbearingcapacitycanbeobtainedfromtheverificationofstressesin

    piles.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –835–

    (8)ExaminationofEmbedmentLengthforLateralResistance

    ① Theembedmentlengthofeachverticalpilemaybedeterminedappropriatelyinaccordancewiththemethodofanalysisofthepilelateralresistance.

    ② Theembedmentlengthsofverticalpilesaregenerallysetat3/βbelowthevirtualgroundsurfacebasedontheresultsofpilelateralresistanceanalyses.Thevalueofβcanbesetinaccordancewith5.2.2 Setting of Basic Cross Section.

    (9)ExaminationofPileJoints

    ①Whenapilejointisneededinapile,itispreferabletoensurethatthepilecankeepitsstabilityagainsttheimpactstressgeneratedinthejointduringdriving.

    ② Thelocationofpilejointshallbedeterminedcarefullyinsuchamannerastoavoidtheportionwithexcessivestress.

    ③ Forthemethodforjoiningpiles,refertoChapter 2, 2.4.6 [4] Joints of Piles.

    (10)ChangeofPlateThicknessorMaterialofSteelPipePile

    ① AnychangeontheplatethicknessormaterialalongthesamesteelpipepileshallbemadeinaccordancewithChapter 2,2.4.6 [5] Change of Plate Thickness or Material Type of Steel Pipe Piles.

    ② Thestrengthsofjointsandportionwithsteelthicknesschangeshouldbeexaminedcarefullybecausetherearesomeexamplesinwhichpilesofopen-typewharvesbuckledattheseportionsduetogrounddeformationinadeepgroundwherenobendingstressesaregeneratedundernormalloadconditions.

    (11)VerificationofLevel2EarthquakeGroundMotionwithaDynamicAnalysisMethod

    ① For setting thecross-section for theverification,anonlineardynamicanalysisofa spring-massmodelwithsinglemassordoublemassesifthereisacontainercraneinstalledmaybeused.Thesystemconsistsofaspringequivalenttothemodeledload-displacementrelationshipofthepiledpierstructureobtainedfromanelastic-plasticanalysis.

    ② If container cranes or other cargo handling equipment are installed on a piled pier, the seismic responsecharacteristicsofthepiledpiermaybegreatlyaltereddependingontheratioofthemassofthecargohandlingequipment to thatof thepiledpierandtheratioof theirnaturalperiods. Therefore, it isnecessarytocarryout a seismic response analysis that takes into consideration the coupled oscillations of the cargo handlingequipmentandthepiledpier.Fordetails,refertoChapter 7 Cargo Handling Facilities,2.2 Fundamentals of Performance Verifi cation.

    ③ Besides the inertia forces actingon the superstructure of thepiledpier, factors that have an adverse effecton thepiles include transmissionof thedeformationof thegroundaround theearth-retainingsection to thesuperstructurethroughtheaccessbridge,andtransmissionofforcestothepileswhenthesoilaroundthepilesmovestowardstheseaduetothedeformationofthesoilsthere. Therefore,astructureoftheaccessbridgeshouldbesuchthatdeformationofthesoilsaroundthegroundearth-retainingsectiondoesnotadverselyaffectthesuperstructureofthepiledpier.

    (12)PerformanceVerificationfortheStabilityoftheEarth-retainingSection

    ① Theexaminationofthestructuralstabilityoftheearth-retainingsectionofopen-typewharfonverticalpilescanbemadeinaccordancewiththeperformancecriteriaprescribedin2.2 Gravity-type Quaywalls, 2.3 Sheet Pile Quaywalls dependingonitsstructuraltype.

    ② The superstructure and the earth-retaining sectionof anopen-typewharf shouldbeconnectedbya simplysupported slab having clearances on its both ends or buffermaterial provided on the both ends of slab, inordertopreventtheforcesactingontheearth-retainingsectionfrombeingtransmittedtothesuperstructure.It isalsopreferable topreparemeasuresagainst therelativelyunevensettlementbetween thewharfand theearth-retainingsection.Furthermore,theclearancebetweenthesuperstructureandtheearth-retainingsectionshould be determined appropriately by considering the dynamic deformation of the superstructure and theearth-retainingsection.

    ③ The stabilityof the earth-retaining sectionofopen-typewharfonvertical piles against circular slip failureshouldbeexaminedbyapplyingChapter 2, 3.2.1 Stability Analysis by Circular Slip Failure Surface.

  • – 836–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    5.2.5 Performance Verification of Structural Members

    (1) Itshallbewellconfirmedthattherewillbenolossoftherequiredfunctioncausedbydeteriorationoftheconcretesuperstructureandthesteelpipepilesubstructureduetomaterialdegradationduringthedesignworkinglife.Inparticulartherehavebeenmanycaseswheretheperformancerequirementsofconcretesuperstructureshavenotbeenachievedasaresultofsaltinjury,soadetailedmaintenancemanagementplanshouldbepreparedandcarriedout.

    (2)Itshallbeverifiedthattheflexuralmoment,axialforce,andshearforceactingontheconnectionsbetweenthesteelpipepilesandthesuperstructuredonotreachtheultimatelimitstate.

    (3)In the performance verification of piled piers, the analysis is carried out by assuming that rigid connectionsbetweenthepileheadsandtheconcretebeamsareformed.Then,itisnecessarythatthepileheadflexuralmomentcanbesmoothlydistributedtothepileheadandtheconcretebeam.TheflexuralmomentthatcanbedistributedtothebeamMudmaybecalculatedusingthefollowingequation,ignoringthereinforcementconnectionplatesorverticalribswhichareprovided,asnecessary.

    (5.2.10)where,

    Mud :flexuralmomentthatcanbedistributedtothepartofthepileembeddedinthebeam(N.mm) D :diameterofsteelpipepile(mm) L :embeddedlengthofsteelpipepile(mm) f 'cd :designvalueofcompressivestrengthofbeamconcrete(N/mm2) γb :memberfactor

    (4)Itisassumedthataxialforcesaredistributedbyonlythebondbetweentheouterperipheralsurfaceofthepilesandtheverticalribs,whichareprovided,asnecessary,andtheconcrete.Inthiscase,theaxialforcethatcanbedistributed,Pud,canbecalculatedfromthefollowingequation.

    (5.2.11)where,

    Pud :axialforcethatcanbedistributedtothepartofthepileembedded(N) L :embeddedlengthofsteelpipepile(mm) φ :outerperimeterofsteelpipepile(mm) fbod :designvalueofthebondstrengthbetweenthepileandtheconcrete(N/mm2) fbod=0.11f 'ck2/3/γc f 'ck :characteristicvalueofthecompressivestrengthoftheconcrete(N/mm2) γc :materialcoefficientofconcrete(=1.3) Ap :areaofverticalribsbondingwithconcrete(mm2) γb :memberfactor(maybetakentobe1.0)

    (5)It shallbeverified that failuredue topunching shear forces in thehorizontaldirection shallnotoccur in thebeamattheendofwhichthesteelpipepileisembedded.Inthiscasethepunchingshearresistance,Vpcd,maybecalculatedfromthefollowingequation.

    (5.2.12)where,

    Vpcd :designvalueofpunchingshearresistanceinthehorizontaldirection(N) f 'cd :designcompressivestrengthofconcrete(N/mm2)

    ifβd>1.5,βdshallbetakentobe1.5

    ifβp>1.5,βpshallbetakentobe1.5

    d :effectiveheight(m) pw :ratioofreinforcementtoconcretesections βγ=1.0 Aτ :shearresistancearea(mm2) γb :memberfactor(maybetakentobe1.3)

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –837–

    5.3 Open-type Wharves on Coupled Raking Piles5.3.1 Fundamentals of Performance Verification

    (1)Thefollowingmaybeappliedtotheopen-typewharveswithastructureinwhichthehorizontalforcesactingonthepiledpieraredistributedtocoupledrakingpiles.

    (2)Theperformanceverificationofopen-typewharvesoncoupledrakingpilesmaybecarriedoutinaccordancewith5.2.4 Performance Verificationforopen-typewharvesonverticalpiles,aswellasthefollowing.

    (3)Theopen-typewharfoncoupledrakingpilesisastructurethatresiststhehorizontalforceactingonthewharfsuchastheseismicactions,fenderreactionforce,andtractiveforceofshipswithcoupledrakingpiles.Therefore,thistypeofwharfmustbeconstructedonthegroundthatyieldssufficientbearingcapacityforcoupledrakingpiles.Becausethecoupledrakingpilesaresolaidouttoresistthehorizontalforcesinthedirectionnormaltothefacelineofthewharf,thehorizontaldisplacementinthatdirectionissmallerthanthatofopen-typewharvesonverticalpiles.Coupledrakingpilesareseldomlaidouttoresistthehorizontalforcesinthedirectionofwharffaceline.Therefore,itispreferabletoexaminethestrengthofthewharfagainstthehorizontalforceparalleltothefacelineinthesamemannerastheexaminationforopen-typewharvesonverticalpiles.

    (4)Inthecaseofcoupledrakingpiles,thepilescomeclosetoadjacentverticalpilesandtheearth-retainingsection,soitispreferablethatthelayoutofthepilesbecarefullydeterminedconsideringtheconstructionconditionsandtheconditionsofuse.

    (5)Fortheprocedureforperformanceverificationofopen-typewharvesoncoupledrakingpiles,referto Fig. 5.3.1 of5.2.4 Performance Verificationforopen-typewharvesonverticalpiles.

    (6)Verification for thevariablesituations in respectofLevel1earthquakegroundmotionmaybecarriedoutbyobtaining the natural periods of the piled pierwith frame analysis and calculating the seismic coefficient forverificationwiththeaccelerationresponsespectrumcorrespondingtothenaturalperiods.

    (7)Anexampleofthecross-sectionoftheopentypewharfoncoupledrakingpilesisshowninFig. 5.3.1.

    L.W.L

    Concrete paving Access bridge

    Water supply pipeSuperstructureSuperstructure

    Backfillingstones

    Earth-retaining sectionRubble mound

    Fenders

    Steel pipe pile Steel pipe pile

    Steel pipe pile Steel pipe pile

    Fig. 5.3.1 Example of Cross-section of Open Type Wharf on Coupled Raking Piles

    5.3.2 Setting of Basic Cross-section

    (1)Forsettingthebasiccross-sectionofopen-typewharvesoncoupledrakingpiles,referto5.2.2 Setting of Basic Cross-section.

    (2)Alargewharffordesignshipsizeof10,000DTWclasshasoneortwosetsofcoupledrakingpilesbehindoneverticalpile in thedirectionnormal to thewharfface line. Thedistancebetweenpilesorbetweencentersof

  • – 838–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    coupledrakingpilesisusuallysettobe4to6minconsiderationofloadingconditionsandconstructionwork.Itispreferabletouseasmallrakingangleofcoupledpilesfromtheviewpointofsecuringresistanceagainsthorizontalforce,butinmanycasesaninclinationof1:0.33to1:0.2isusedbecauseofconstraintsrelatedtotherequireddistancesfromotherpilesandconstructionwork-relatedconstraintssuchasthecapacityofpiledrivingequipmentavailable.

    5.3.3 Actions

    The characteristic value of the seismic coefficient for verification used in performance verification of open-typewharveson coupled rakingpiles for thevariable situations in respectofLevel1 earthquakegroundmotion shallbe appropriately calculated considering the structural characteristics of thewharf. For calculationof the seismiccoefficientforverificationofopen-typewharvesoncoupledrakingpiles,referto5.2.3(10) Ground Motion used in Performance Verification of Seismic-resistant.

    5.3.4 Performance Verification

    (1) ItemsforthePerformanceVerificationofOpen-typeWharvesonCoupledRakingPilesThe performance verification of open-type wharves on coupled raking piles shall apply 5.2.4 Performance Verificationandbebasedonthefollowing.

    (2)PerformanceVerificationofBearingForcesonPiles

    ①Thepushing-inandpulling-outforcesofeachpairofcoupledrakingpilesshallbecalculatedappropriatelybasedontheverticalandhorizontalforcesdefinedinconsiderationofthewharfoperationconditions.

    ② Thepushing-inandpulling-outforcesoneachrakingpileareobtainedwithaframeanalysismethod,takingintoconsiderationtheeffectoftherakingangleofthepileasindicatedinChapter 2, 2.4.5 Static Maximum Lateral Resistance of Piles,calculatingtheratioofthecoefficientoflateralsubgradereaction,andappropriatelycorrectingthecoefficientoflateralsubgradereaction.

    ③ For verification of pushing-in and pulling-out forces in each raking pile, refer toChapter 2 2.4.3 Static Maximum Axial Pushing Resistance of Pile Foundations,and2.4.4 Static Maximum Pulling Resistance of Pile Foundations.

    (3)VerificationofStressesinPilesThecross-sectionalstressineachpilemaybecalculatedbyapplying5.2.4 Performance Verificationforpilessubjecttoaxialforcesorpilessubjecttoaxialforcesandflexuralmoments.

    (4)Horizontal Forces Distributed to the Pile Head of each Group when Rotation of the Piled Pier Block isConsidered

    ①Whenitisnecessarytoconsiderrotationofthepiledpierblock,thehorizontalforcesdistributedtothepileheadofeachgroupofpilesinanopentypewharfoncoupledrakingpilesmaybeappropriatelycalculatedinaccordancewiththecross-sectionofeachpileandtherakingangleandlengthoftherakingpiles.Inthiscase,itmaybeassumedthatallhorizontalforcesaredistributedtothecoupledrakingpiles.Normallytherowofpileshavingthemaximumdistributedhorizontalforceamongalltherowsofpilesisadoptedastherowofpilesusedintheverification.

    ② Inthecasewherethecross-sectionofeachpilegroupandrakingangleoftherakingpilesaredifferent, thehorizontalforcedistributedtothepileheadofeachgroupmaybecalculatedusingequation(5.3.1)(seeFig. 5.3.2).

    (a)Whenthepilescanberegardedasfullyendbearingpiles

    (5.3.1)

    where,

    H :horizontalforceactingontheblock(N/m) Hi :horizontalforcedistributedtoeachpile(N/m)

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –839–

    e :distancebetweencenterlineofpilegroupandtheactinghorizontalforce(m) xi :distancefromeachpilegrouptothecenterlineofapilegroup(m) i :totalpilelength(m),beingsubstitutedthepilelengthofthefrictionpilewhenpulling-outforces

    areacting. Ai :cross-sectionalareaofeachpile(m2) Ei :Young’smodulusofeachpile(N/m2) θi1,θi2:angleofeachpilewiththeverticaldirection(°)

    Thesubscriptireferstotheithpile. Thesubscripts1,2refertoeachpileinonepilegroup. ThecenterlineofapilegroupmaybeobtainedfromΣCiξi/ΣCi. ξiarethecoordinatesfromanarbitrarycoordinateoriginofeachpilegroupinfacelinedirection.

    (b)Whenthepilescanberegardedfullyasfrictionpiles

    1) Sandysoil

    Equation(5.3.1)isused,substituting, fori.

    2) Cohesivesoil

    Equation(5.3.1)isused,substituting, fori.

    where, λi: Pile length of the part overwhich the peripheral surface resistance force is not effectivelyworking(m),i:Totalpilelength(m).

    Pile group center lineH

    e

    x1 x2

    x3 x4

    Coupled piles

    Vertical pilesHorizontal force H

    Fig. 5.3.2 Pile group Center Line and Distance from each Pile Group

    ③Whenthecross-section,rakingangleandlengthoftherakingpilesofeachpilegroupareallequal,thehorizontalforcedistributedtoeachpilegroupmaybecalculatedfromequation(5.3.2).

    (5.3.2)

    (5)PartialFactorsVerificationmaybeappropriatelycarriedoutusingpartialfactorsforverificationofbearingcapacityofpilesandstressesinthepilesofopen-typewharvesoncoupledrakingpilessubstitutedwiththoseforopen-typewharvesonverticalpiles,consideringthesimilarityofperformanceverificationmethodamongthesetwotypesofstructures.

    (6)AnalysisintheFaceLineDirectionIftherearecoupledrakingpilesinthefacelinedirection,theanalysisshouldbecarriedoutusingthemethoddefinedin(2)to(5),inthesamewayasthedirectionperpendiculartothefaceline.

    (7)VerificationofPileEmbedmentForbearingcapacityonrakingpiles,referto5.2.4 Performance Verification.

  • – 840–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    (8)PerformanceVerificationofEarth-retainingSections

    ① Fortheperformanceverificationofearth-retainingsections,referto5.2.4 Performance Verification.

    ② Itshallbeensuredthattheactionduetodeformationoftheearth-retainingsectionbyearthquakesshallnotbetransmittedtothesuperstructureofthepiledpierviatheaccessbridge,andthatthepilesarenotadverselyaffectedbysignificantdeformationofthesoilaroundthepilestowardsthesea.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –841–

    5.4 Strutted Frame Type Pier

    (1)Performanceverificationofstruttedframetypepiersshallapply5.2 Open-type Wharves on Vertical Piles,and5.3 Open-type Wharves on Coupled Raking Piles,andalsorefertotheStrutted Frame Method Technical Manual.22)

    (2)The characteristic value of the seismic coefficient for verification used in the performance verification ofstrutted frame typepiersagainst thevariablesituations in respectofLevel1earthquakegroundmotionshallbeappropriatelycalculatedconsideringthestructuralcharacteristics.Forcalculationoftheseismiccoefficientforverificationofstruttedtypepiers,referto5.2.3(10) Ground Motions used in Performance Verification of Seismic-resistant.

  • – 842–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    5.5 Jacket Type Piled PiersPublic NoticePerformance Criteria of Piled Piers

    Article 55 1TheprovisionsofArticle48shallbeappliedtotheperformancecriteriaofpiledpierswithmodificationasnecessary.

    2Inadditiontotherequirementsoftheprecedingparagraph,theperformancecriteriaofpiledpiersshallbeasspecifiedinthesubsequentitems:(1)Theaccessbridgeofapiledpiershallsatisfythefollowingcriteria:(a)Itshallhavethedimensionsrequiredforenablingthesafeandsmoothloading,unloading,embarkation

    anddisembarkation,andothersinconsiderationoftheusageconditions.(b)Itshallnottransmitthehorizontalloadstothesuperstructureofthepiledpier,anditshallnotfall

    downevenwhenthepiledpierandtheearth-retainingpartaredisplacedowingtotheactionsofearthquakesorsimilarone.

    (2)The following criteria shall be satisfied under the variable action situation inwhich the dominantactionsareLevel1earthquakegroundmotions,shipberthingandtractionbyships,andimposedload:(a)Theriskofimpairingtheintegrityofthemembersofthesuperstructureshallbeequaltoorlessthan

    thethresholdlevel.(b)Theriskthattheaxialforcesactinginthepilesmayexceedtheresistancecapacityowingtofailure

    ofthegroundshallbeequaltoorlessthanthethresholdlevel.(c)Therisk that thestress in thepilesmayexceedtheyieldstressshallbeequal toor less thanthe

    thresholdlevel.(3)Thefollowingcriteriashallbesatisfiedunderthevariableactionsituationinwhichthedominantaction

    isvariablewaves:(a)Theriskoflosingthestabilityoftheaccessbridgeduetoupliftactingontheaccessbridgeshallbe

    equaltoorlessthanthethresholdlevel.(b)Theriskofimpairingtheintegrityofthemembersofthesuperstructureshallbeequaltoorlessthan

    thethresholdlevel.(c)Theriskthattheaxialforcesactinginpilesmayexceedtheresistancecapacityowingtofailureof

    thegroundshallbeequaltoorlessthanthethresholdlevel.(4)Inthecaseofstructureshavingstiffeningmembers,theriskofimpairingtheintegrityofthestiffening

    membersandtheirconnectionpointsunderthevariableactionsituationinwhichthedominantactionsare variable waves, Level 1 earthquake groundmotions, ship berthing and traction by ships, andimposedloadshallbeequaltoorlessthanthethresholdlevel.

    3TheprovisionsofArticle49 throughArticle52shallbeappliedwithmodificationasnecessary to theperformancecriteriaoftheearth-retainingpartsofpiledpiersinconsiderationofthestructuraltype.

    [Technical Note]

    (1)Theperformanceverificationof jacket typepiledpiersorpiledpierswhose structurehas stiffeningmembers shall apply5.2 Open-type Wharves on Vertical Piles, and5.3 Open-type Wharves on Coupled Raking Piles,andfordetailsrefertotheJacket Method Technical Manual.23)

    (2)ThecharacteristicvalueoftheseismiccoefficientforverificationusedintheperformanceverificationofjackettypepiledpiersinthevariablesituationsinrespectofLevel1earthquakegroundmotionshallbe appropriately calculated considering the structural characteristics. For calculationof the seismiccoefficient for theverificationof jacket typepiledpiers, refer to5.2.3(10) Ground Motions used in Performance Verification of Seismic-resistant.

    (3)VerificationofLevel2EarthquakeGroundMotionwiththeDynamicAnalysisMethodTheperformanceverificationofjackettypepiledpiersinaccidentalsituationsinrespectoflevel2earthquakegroundmotionshallbeappropriatelycarriedoutconsideringtheconcernedcircumstancesaroundthefacilities,

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –843–

    importanceof thefacility,andtheaccuracyof themethod. Theperformanceverificationof jacket typepiledpiersmaycomplywiththatofopen-typewharvesonverticalpiles,buttheactionsoccurringinthemembersshallbeappropriatelysetconsideringthestructureofthetrusses.Thedifferentpointsinthedynamiccharacteristicsbetweenjackettypepiledpiersandopen-typewharvesonverticalpilesareasfollows.

    (a) Thenaturalperiodsareshortduetothenatureoftrussstructure(b)Becausethestructurehaspanelpoints,thefailuremechanismsarecomplex(c)Separateverificationofthepanelpointsisnecessary

  • – 844–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    5.6 Dolphins5.6.1 Fundamentals of Performance Verification

    (1)Thefollowingmaybeappliedtotheperformanceverificationofsuchmooringfacilitiesaspiletype,steelcelltype,caissontype,andothertypedolphinstructures.Dependingontheirfunction,thetypesofdolphinincludebreastingdolphins,mooringdolphinsandloadingdolphins.

    (2)Theguidelinesoutlinedin5.6.2 Actions,and5.6.3 Performance Verificationmaybeusedinsimpleverificationmethods,thus,thispointshouldbenotedwhentheyareadopted.

    (3)Itispreferablethatperformanceverificationofdolphinsbecarriedoutconsideringthefollowingitems.Forotheritems,itispreferabletoappropriatelycarryouttheperformanceverificationinaccordancewitheachstructuralform.

    ① Thedirectionofactionsondolphinsisnotnecessarilyaconstantdirection,hence,theverificationshouldbecarriedoutforseveraldirections,asnecessary.

    ② Conventionallytorsioninthecaseofpiletypestructuresandrotationinthecaseofcaissontypestructureshavenotbeenexaminedverymuch.However,thesefactorsmayaffectthestabilityofstructuresincertaincases,thus,itisnecessarytobecarefulabouttheseaspects.

    ③ It ispreferable toappropriatelyset thecrownheightof thedolphin inaccordancewith its function. In thisconnectionthepositionofinstallationofthefendersforbreastingdolphins,thelevelofthedeckoftheshipformooringdolphins, and theworking rangeof the loading arm for loadingdolphins shouldbe taken intoconsideration. Forconnectingbridges, it ispreferable that theheightbesufficientnot tobeaffectedby theactionofwaves.

    (4)Anexampleofthecross-sectionofapiletypedolphinisshowninFig. 5.6.1.

    Mooring dolphin

    Bitt

    Loading piled pierLoading piled pier Loading piled pierLoading piled pier

    Mooring post

    Mooring dolphinMooring postBitt

    H.W.O.S.T.

    Seabed surface

    Mooring post

    L.W.O.S.T.

    Bearing ground

    Breasting dolphin

    Fig. 5.6.1 Example of Cross-section of Pile Type Dolphin

    (5)Layout

    ① Thelayoutofadolphin-berthshallbedeterminedappropriatelytoavoidadverseeffectsonthenavigationandanchorageofothershipsinconsiderationofthedimensionsofthedesignships,waterdepth,winddirection,wavedirection,andtidalcurrents.

    ② Inthedeterminationofthelayoutofbreastingdolphins,thefollowingitemsneedtobeexamined:

    (a) Dimensionsofthedesignship

    1) Thesideofdesignshipsisusuallycomposedofcurvelinesformingtheoutlinesof thebowandsternparts,eachofwhichaccountsforabout1/8ofthelengthoverall(L)ofship,respectivelyandastraightlineformingtheoutlineofthecentralpartwhichaccountsforabout3/4ofthelengthoverall(L)ofship..Itispreferablethatthebreastingdolphinsareinstalledinsuchawaythattheshipscanbeberthedtothemwiththestraightlinepart.Normallythenumberofbreastingdolphinsisoneeachtowardthebowandstern,butfordolphinsservingforbothlargeandsmallships,twoeachtowardbowandsternaresometimesprovided.

    2) Whenspecialcargohandlingequipmentisrequiredfordolphinsinsuchacaseasdolphinsforoilhandling,

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –845–

    acargohandlingplatformisinstalledmidwaybetweenthebreastingdolphins.Inthiscase,itispreferabletolocatethecargohandlingplatformwithitsseasidefrontslightlybackwardfromthatofthebreastingdolphins,inorderthattheshipberthingforcedoesnotactdirectlyonthecargohandlingplatform.

    (b)It is preferable to layout dolphins in away that the longitudinal axis of dolphins becomesparallel to theprevailingdirectionsofwinds,waves,andtidalcurrents.Thishelpstoeaseshipmaneuveringduringberthingandunberthingandtoreduceexternalforcesactingonthedolphinswhentheshipismoored.

    ③ Mooringdolphinsarenormallysetatthepositionswiththeangleof45ºfromtheropebittsonship’sbowandstern,havingacertainsetbackfromthefrontfaceofthebreastingdolphins.

    ④ Thedistancebetweenbreastingdolphinsiscloselyrelatedtothelengthoverall(L)ofthedesignships.Fig. 5.6.2 givestherelationshipbetweenthebreastingdolphinintervalandthewaterdepthderivedfromthepastconstructiondataforreference.

    Pile typeSteel sheet pile cell typeCaisson type

    Bre

    astin

    g do

    lphi

    n in

    terv

    al( m

    )

    Water depth (m)

    Fig. 5.6.2 Distance between Breasting Dolphins

    5.6.2 Actions

    (1)Forcalculationofthereactionforcefromthefendersontothedolphins,refertoPart II, Chapter 8, 2.2 Action Caused by Ship Berthing,andChapter 5, 9.2 Fender Equipment.

    (2)Forcalculationofthetractiveforceofships,refertoPart II, Chapter 8, 2.4 Action due to Traction by Ships.

    (3)Forcalculationofverticalloadsduetoselfweightandliveload,refertoPart II, Chapter 10, Self Weight and Surcharge, 5.2.3 Actions,asappliedforopen-typewharvesonverticalpiles.

    (4)Fortheactionduetoearthquakes,refertoPart II, Chapter 4, Earthquakes and 5.2.3 Actions,asappliedforopen-typewharvesonverticalpiles.

    (5)Forcalculationofthedynamicwaterpressureduringanearthquake,refertoPart II, Chapter 5, 2.2 Dynamic Water Pressure.

    (6)Forcalculationofwindpressureforcesactingoncargohandlingequipment,refertoPart II, Chapter 2, 2.3 Wind Pressure.

  • – 846–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    5.6.3 Performance Verification

    [1] Pile Type Dolphins

    (1)Fortheperformanceverificationofpiletypedolphins,referto5.2 Open-type Wharves on Vertical Piles,and5.3 Open-type Wharves on Coupled Raking Piles.

    (2)The characteristic valueof the seismic coefficient for theverification used in theperformanceverification ofpiletypedolphinsinvariablesituationsinrespectofLevel1earthquakegroundmotionshallbeappropriatelycalculatedconsideringthestructuralcharacteristics.Forcalculationoftheseismiccoefficientfortheverificationofpiletypedolphins,referto5.2.3(10) Ground Motions used in Performance Verification of Seismic-resistant.

    (3)Inthecaseofpile typedolphins, theberthingenergymaynormallybecalculatedontheassumptionthat it isabsorbedbythedeformationsofthefendersandthepiles.

    (4)Large tankers are usually berthed at a slant anglewith the dolphin alignment line. As the characteristics offendersvarydependingontheberthingangle,itisrecommendedinsuchacasetousethecharacteristicscurveappropriatetotheberthingangle.Inaddition,aslantingberthingentailstheriskthatsomeofthefendersattachedto abreastingdolphinmaynot absorb theberthingenergyeffectively. Therefore, it ispreferable to examinecarefullywhichfenderswillcomeincontactwiththehullofshipinconsiderationoftheberthingangle.

    [2] Steel Cell Type Dolphins

    (1)For theperformanceverificationof steel cell typedolphins, refer to2.9 Cellular-bulkhead Quaywalls with Embedded Sections.

    (2)Thecharacteristicvalueof theseismiccoefficient for theverification for theperformanceverificationofsteelcelltypedolphinsinvariablesituationsinrespectofLevel1earthquakegroundmotionshallbeappropriatelycalculated considering the structural characteristics. The characteristic value of the seismic coefficient forverificationofsteelcelltypedolphinsmaybecalculatedinaccordancewithgravity-typequaywallbyapplying2.2.2(1) Seismic coefficient for verification used for verification of sliding and overturning of wall body and insufficient bearing capacity of foundation grounds in variable situations in respect of level 1 earthquake ground motionwhensoilpressureisacting,orcompositebreakwatersbyapplyingChapter 4, 3.1.4(12) Seismic Coefficient for Verification of Sliding, Overturning, and Bearing Capacity of Upright Sections for Level 1 Earthquake Ground Motion,whensoilpressureisnotacting.

    (3)Forthefoundationsofcargohandlingequipmentandmooringposts,refertoChapter 2, 2.4 Pile Foundations, and 9.15 Foundations for Cargo Handling Equipment.

    (4)Inthecaseofacylindricalcelltypedolphin,theequivalentwallwidthcanbecalculatedusingequation(5.6.1).

    (5.6.1)where

    B :equivalentwallwidth(m) R :radiusofcylindricalcell(m)

    [3] Caisson Type Dolphins

    (1)Fortheperformanceverificationofcaissontypedolphins,referto2.2 Gravity-type Quaywalls.

    (2)Thecharacteristicvalueoftheseismiccoefficientforverificationofcaissontypedolphinsmayapplysteelcelltypedolphins.

    (3)Rotationofacaissonoccurswhenaneccentricexternalforceactsonadolphin.Examinationofstabilityagainstrotationmustbemadeevenwhenthestabilityagainstslidingandoverturningaswellasagainstfailureofthefoundationgroundduetoinsufficientbearingcapacityarefoundtobesatisfactory,becausetheconfirmationofthestabilitywithrespecttotheseitemsdoesnotguaranteethatthecaissonissafeagainstrotation.Inthiscase,incalculatingtheresistanceforce,attentionshouldbegiventothefrictionforceofthecaissonbottomwhichisproportionaltothebottomreactionforceasdescribedinChapter 2, 1.2 Caissons.

    (3)For theperformanceverificationof structuralmembers, refer to [1] Pile Type Dolphins. Inaddition, for theverificationofcaissonmembers,refertoChapter 2, 1.2 Caissons.

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –847–

    5.7 Detached Piers5.7.1 Fundamentals of Performance Verification

    (1)The performance verification of the detached piersmaybe carried out by appropriately selecting items from5.2 Open-type Wharves on Vertical Piles,5.3 Open-type Wharves on Coupled Raking Piles,2.2 Gravity-type Quaywalls, and 2.9 Cellular-bulkhead Quaywalls with Embedded Sections, in accordancewith thestructuretype.Also,theperformanceverificationoftheearth-retainingpartmaybecarriedoutbyappropriatelyselectingitemsfromperformancecriteriaof2.2 Gravity-type Quaywalls, 2.3 Sheet Pile Quaywalls, and 2.4 Cantilevered Sheet Pile Quaywalls,andinadditionrefertothefollowing.

    (2)Thefollowingmaybeappliedtotheperformanceverificationofthedetachedpierscomprisingthedetachedpierandtheearth-retainingsection.

    (3)AnexampleoftheprocedureofperformanceverificationofthedetachedpiersisshowninFig. 5.7.1.Setting of design conditions

    Verification in accordance with structural type of pile

    Verification of earth-retaining section

    Determination of cross-sectional dimensions

    Performance verification of members of superstructure, access bridge, etc.

    Performance verification of beams, etc.

    Permanent state, variable states in respectof action of ships, Level 1 earthquake ground motion, action of waves, and surcharges

    Permanent state

    Variable states in respect of action of ships,Level 1 earthquake ground motion, and action of waves

    Performance verificationPerformance verificationEvaluation of actions

    Setting of basic cross-section*1

    *1:Theevaluationoftheeffectofliquefactionisnotindicated,thereforeitisnecessarytoconsiderthisseparately.

    Fig. 5.7.1 Example of Procedure of Performance Verification of Detached Piers

    (4)Anexampleofacross-sectionofadetachedpierisshowninFig. 5.7.2.

  • – 848–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    H.W.L

    Rail center line on sea side Yard bridge (PC slab bridge)

    Yard bridge (PC slab bridge)

    Rail center line on land side

    Caisson

    L.W.L

    Fig. 5.7.2 Example of Cross-section of Detached Pier

    (5)It isnecessary topayadequateattention to thedeformationof theearth-retainingsectiondue to theactionofearthquakes.

    (6)Theperformanceverificationofthedetachedpiershallbeconductedsothatitisstableagainstalltheactionsonthepilesandgirders.Inaddition,itispreferableforthedetachedpiertohaveastructurewithdueconsiderationforthetypeanddimensionsofportalbridgecrane,thetravelingcharacteristics,andthesettlementofrailsafterinstallation.

    (7)Railmountedcranesareinstalledondetachedpiers,thereforeitispreferablethatthestructureshallhaveasmalldeformation.

    5.7.2 Actions

    (1)Forthewheelloadsofcargohandlingequipment,refertoPart II, Chapter 10, 3.2 Live Load.

    (2)Fortractiveforcesofship,refertoPart II, Chapter 8, 2.4 Action due to Traction by Ships.

    (3)Fortheselfweightofsuperstructures,andselfweightofpiles,refertoPart II, Chapter 10, 2 Self Weight,andChapter 10, 3 Surcharge.

    (4)Forfenderreactions,refertoPart II, Chapter 8, 2.2 Action Caused by Ship Berthing, Part II, Chapter 8, 2.3 Action Caused by Ship Motions.

    (5)Forwindloadsactingoncargohandlingequipmentandsuperstructures,refertoPart II, Chapter 2, 2.3 Wind Pressure.

    (6)Forthegroundmotionsactingoncargohandlingequipment,superstructures,andpiles,refertoPart II, Chapter 4, 2 Seismic Action.

    (7)Thecharacteristicvalueoftheseismiccoefficientforverificationfortheperformanceverificationofthedetachedpiers against the variable situations in respect of Level 1 earthquake ground motion shall be appropriatelycalculatedconsideringthestructuralcharacteristics.Forcalculationoftheseismiccoefficientforverificationofthedetachedpiers,referto5.2.3(10) Ground Motion used in Performance Verification of Seismic-resistant.

    (8)Fortheperformanceverificationofthedetachedpiers,itispreferabletoconsiderwaveforces,upliftpressure,andwindloadsactingonsuperstructures,whennecessary.

    (9)Fortheperformanceverificationofthebeams,brakingforcesoncargohandlingequipmentshallbeconsideredasahorizontalforce,butforpilesshallbeconsidered,asnecessary.

    (10)Fortheperformanceverificationoftheaccessbridgesandthefloorslabs,aliveloadof5.0kN/m2maybeassumed.

    5.7.3 Performance Verification

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –849–

    PerformanceVerificationofGirder

    ① Theperformanceverificationofgirdersshallbeconductedsothattheyaresafeagainsttheverticalaswellashorizontalforcesandloads.

    ② Structuralelementswithsufficientstrengthagainstthedesignatedverticalandhorizontalforcesshallbeusedforthegirdersofthedetachedpier,becausethecranerailsforacranearedirectlyinstalledonthegirders.Intheexaminationofverticalloads,theincreaseinthewheelloadsduetothewindloadorseismicforceactingonthebridgecraneshallbetakenintoaccount.

    ③Whenboth legsof thebridgecranearefixedones, thehorizontal loadactingoneach leg isdeterminedbydistributingthetotalhorizontalloadtoeachlegbasedontheproportionofthewheelload.Whenthebridgecranehasafixedlegandasuspendedleg,thewholehorizontalloadshallbebornebythefixedlegformakingthedesignonthesaferside.Atthesametime,however,thehorizontalforcebeingone-halfoftheforceactingononefixedleginthecaseofthebothlegsbeingfixedshallbebornebythesuspendedleg.

    References

    1) SUZUKI,A.,KoichiKUBOandYoshioTANAKA:Lateralresistanceofverticalpilesembeddedinsandylayerwithslopingsurface,Rept.ofPHRIVoL5,No.2,1966

    2) Kikuchi,Y.,T.Ogura,M.IshimaruandT.Kondo:Coefficientoflateralsubgradereactionofrubbleground,Proceedingsof53rdAnnualConferenceofJSCE,1998

    3) YAMASHITA,I.:EquivalentRigidFrametoVerticalPileStructureontheBasisofthePHRIMethod,TechnicalNoteofPHRINo.105,pp.1-12,1970

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    C-TypeSoil,TechnicalNoteofPHRINo.650pp」3-25,19696) YAMASHITA,I.,T.INATOMI,K.OGURAandY.OKUYAMA:NewStandardCurvesinthePHRIMethod,Rept.ofPHRI

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    17) Yoshikawa,S.,D.Kyoku,Y.Tame,Y.Tame,S. Iai andY.Umeki:Two-dimensionalFiniteElementMethodanalysisofhorizontalloadingtestofasinglepileutilizinginteractionspringonformationlawofsoil,-Clayeyground-.Proceedingsof58thAnnualConferenceofJSCE,2003

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    of58thAnnualConferenceofJSCE,200322) CoastalDevelopmentInstituteofTechnology(CDIT):TechnicalManualforGridStrutMethod,200023) CoastalDevelopmentInstituteofTechnology(CDIT):TechnicalManualforJacketstructures,200024) JapanRoadAssociation:SpecificationsandCommentaryforHighwayBridges,MaruzenPublications,200425) JapanRoadAssociation:TechnicalStandardsandcommentaryofelevatedpedestriancrossingfacilities,1979

  • PART III FACILITIES, CHAPTER 5 MOORING FACILITIES

    –851–

    6 Floating PiersMinisterial OrdinancePerformance Requirements for Floating Piers

    Article 30 1Theperformancerequirementsforfloatingpiersshallbeasspecifiedinthesubsequentitemsinconsiderationofitsstructuretype.(1)TherequirementsspecifiedbytheMinisterofLand,Infrastructure,TransportandTourismshallbe

    satisfiedsoas toenable thesafeandsmoothmooringofships,embarkationanddisembarkationofpeople,andhandlingofcargo.

    (2)Thedamageduetoselfweight,variablewaves,Level1earthquakegroundmotions,shipberthingandtractionbyships,and/orotheractionsshallnotimpairthefunctionofthefloatingpiernoraffectitscontinueduse.

    2Inadditiontotheprovisionsoftheprecedingparagraph,theperformancerequirementofthefloatingpiersintheplacewherethereisariskofhavingseriousimpactonhumanlives,property,and/orsocioeconomicactivitybythedamagetothemooringbuoysconcernedshallbesuchthatthestructuralstabilityofthefloatingpierisnotseriouslyaffectedevenincaseswhenthefunctionofthemooringbuoysconcernedisimpairedbytsunamis,accidentalwaves,and/orotheractions.

    Public NoticePerformance Criteria of Floating Piers

    Article 56 1Theprovisionsofparagraph1ofArticle48(excludingitemii))shallbeappliedtotheperformancecriteriaoffloatingpiers.

    2Inadditiontotheprovisionsintheprecedingparagraph,theperformancecriteriaoffloatingpiersshallbeasspecifiedinthesubsequentitemsinconsiderationofthestructuraltype:(1)Thefloatingpiershallhavethedimensionsrequiredforcontainmentoftheirmovementsandtilting

    withintheallowablerangeinconsiderationoftheusageconditions.(2)Theriskofcapsizingofthefloatingbodyunderthevariableactionsituationinwhichthedominant

    actionisvariablewavesshallbeequaltoorlessthanthethresholdlevel.(3)Thefloatingpiershallhavethefreeboardrequiredforthedimensionsofthedesignshipsandtheusage

    conditions.(4)The following criteria shall be satisfied under the variable action situation inwhich the dominant

    actionsareLevel1earthquakegroundmotions,shipberthingandtractionbyships,andimposedload:(a)Theriskofimpairingtheintegrityofthemembersofthesuperstructureshallbeequaltoorlessthan

    thethresholdlevel.(b)Theriskofimpairingtheintegrityofthemembersofthefloatingmooringfacilitiesandlosingthe

    structuralstabilityshallbeequaltoorlessthanthethresholdlevel.3Inadditiontotheprovisionsoftheprecedingtwoparagraphs,theperformancecriteriaoffloatingpiersforwhichthereisariskofseriousimpactonhumanlives,property,orsocioeconomicactivitybythedamagetothefacilitiesconcernedshallbesuchthatthedegreeofdamageundertheaccidentalactionsituation,inwhichthedominantactionsaretsunamisoraccidentalwaves,isequaltoorlessthanthethresholdlevel.

    4 The provisions of Article 64 and Article 91 shall be applied with modification as necessary to theperformance criteria of the access facilities of the floating body by taking account of the utilizationconditions.

    [Commentary]

    (1)PerformanceCriteriaofFloatingPiers①Commonforfloatingpiers(a)Insettingthecross-sectionaldimensionsfortheperformanceverificationoffloatingpiers,itshallbe

  • – 852–

    TECHNICAL STANDARDS AND COMMENTARIES FOR PORT AND HARBOUR FACILITIES IN JAPAN

    appropriatelyverifiedthattheamountofmotionsofthefloatingbodyandtheamountoftiltingofthefloatingbodyarewithintheallowablerange,inaccordancewiththeenvisagedconditionsofuse,asnecessary.

    (b)Freeboard(usability)Fortheperformancecriteriaoffloatingpiers,thefreeboardofthefloatingpiershallbeappropriatelysetconsideringthedimensionsofthedesignshipsandtheenvisagedconditionsofusetoallowsafeandefficientembarkationanddisembarkationofpassengersandsafeandefficienthandlingofcargo.(c)Structuralstabilityandsoundnessofmembers(serviceability)

    1) Thesettingof theperformancecriteria for the structural stabilityandsoundnessofmembersoffloatingpiersandthedesignsituationsexcludingaccidentalsituationsshallbeinaccordancewithAttached Table 50. In the performance verification of floating piers, the performancecriteriaforvariablesituationinrespectofvariablewaves,Level1earthquakegroundmotion,berthingandtractionbyships,surcharges,forwhichperformanceverificationisnecessary,shallbe appropriately set, in accordancewith the structure type of the facility. The itemswithinparenthesesinthecolumnof“Designsituation”inAttached Table 50maybeappliesindividually.

    Attached Table 50 Setting of Performance Criteria for Structural Stability and Soundness of Structural Members of Floating Piers and Des