Upload
hermann-pankow
View
213
Download
0
Embed Size (px)
Citation preview
7/30/2019 Opciones en Puentes
1/4
4HEREARESEVERALGOODREASONSWHYPRECASTPRESTRESSEDCONCRETEBRIDGES
HAVEGAINEDSUCHWIDEACCEPTANCE3OMEBRIDGEDESIGNERSARESURPRISEDTOLEARNTHATPRECASTPRESTRESSEDCONCRETEBRIDGESAREUSUALLYLOWERINlRSTCOSTTHANOTHERTYPESOFBRIDGES#OUPLEDWITHSAVINGSINMAINTENANCEPRECASTBRIDGESOFFERMAXIMUMECONOMY#ASEAFTERCASECANBECITEDATLOCATIONSTHROUGHOUTTHE5NITED3TATESANDTHESEBRIDGESAREATTRACTIVEASWELLASECONOMICAL
4HEOVERALLECONOMYOFASTRUCTUREISMEASUREDINTERMSOFITSLIFECYCLECOSTS4HISINCLUDESTHEINITIALCOSTOFTHESTRUCTUREPLUSTHETOTALOPERATINGCOSTS&ORSTATIONARYBRIDGESTHEOPERATINGCOSTISTHEMAINTENANCE
COST0RECASTPRESTRESSEDCONCRETEBRIDGESDESIGNEDANDBUILTINACCORDANCEWITH!!3(4/OR!2%-!SPECIlCATIONSSHOULDREQUIRELITTLEIFANYMAINTENANCE"ECAUSEOFTHEHIGHQUALITYOFMATERIALSUSEDPRESTRESSEDMEMBERSAREPARTICULARLYDURABLE&ATIGUEPROBLEMSARENONEXISTENTBECAUSETRAFlCLOADSINDUCEONLYMINORNETSTRESSES
!DVANTAGESOF0RESTRESSED#ONCRETE"RIDGES
,OW)NITIAL#OST
4HESTATEOF-INNESOTASAVEDMORETHANnHALFAMILLIONDOLLARSnBYPLANNINGFORAPRESTRESSEDALTERNATETOASTEELBRIDGE4HEFOOTLONGBRIDGEISJOINTLESSUPTOTHEABUTMENTSANDISTHELONGESTCONTINUOUSBRIDGEINTHESTATE)TALSOCONTAINEDTHESTATESLONGESTSINGLECONCRETESPAN!-INNESOTATRANSPORTATIONOFlCIALSTATEDh/RIGINALLYWEDIDNTTHINKCONCRETEWASSUITEDTOTHISxBRIDGE(OWEVERTHEFABRICATORSHOWED
USITWASAVIABLEALTERNATIVE%VERYTHINGWENTSMOOTHLYxWEREWELLSATISlEDxv
-INIMAL-AINTENANCE
/NTHE)LLINOIS4OLL(IGHWAY3YSTEMDURINGANDTHESUPERSTRUCTURESOFMORETHANBRIDGESWEREBUILTWITHPRECAST
PRESTRESSEDCONCRETE)BEAMS4HEYSPANUPTOFEETANDSOMEOFTHEMHAVEPRECASTSTAYINPLACEDECKPANELSPRECASTDIAPHRAGMSANDUSESPUNCASTHOLLOWCYLINDERPILECOLUMNBENTS4HEYHAVEWITHSTOODHEAVYTRAFlCSEVEREWEATHERINGANDVERYHIGHSALTAPPLICATIONS9ETTHESEBRIDGESHAVEREQUIREDVERYLITTLEMAINTENANCE/THERPROJECTSINALLPARTSOF.ORTH!MERICAHAVEEXHIBITEDSIMILAREXPERIENCEnLITTLEORNOMAINTENANCEHASBEENREQUIREDONPRECASTPRESTRESSEDCONCRETEBRIDGES
7/30/2019 Opciones en Puentes
2/4
U ,i`Vv`i>]V>>`>VV`iVV`}>iLi/i>/>>i]VVi`L`i>}}>i]>}i}ii}V]V>Lif]f]i`>L>>i>]>vi`i>i>i>iVviV>i>Vfx]i`>
>/>vwV
->>]*i,V]iv]>iV>VVii>``i>iiL`}iiiLiV`i}i]>>Vi>`iVV> >VvvL }i]>}}i}vvii]>iiVi`i>q>vii>vwV>
ii``>}>vwVii`iiiL`}i->`>-`>t/V`i`ii]iiVi]ii>>`}}>iiiVV>>ViviL`}i>V`i>Li`i`iviV}>ii`V` >` ii ]iL`}i>iiVL`}i>ii`/ivL
Li>L`}iiiVVi`vfi>iiiL`v>i>i>>``]iL`}ii`>Li>`>i>Vivii]>``}>iii
" ! !#
! !!
!
!
! #
!!
7/30/2019 Opciones en Puentes
3/4
4HE&UTURE
>L`}iVV>Lii]>`ViLii}}vViiV>VVii`/i`iiiv>Vi`iV>VViiL`}iiVi>ivi>
i`iii>iiviV>`iV>i1i`>>>Viv]i>ii>viiLi]i`Viwi`>ViivivV}ii>`VViivL`}i`iV]i}V`i>Li>}/i>iLiViVivi>`iwi`>Vi`VVii>`>iV>>i
7/30/2019 Opciones en Puentes
4/4
*,-1 #(!04%2
1{
/PENTOPPED TRAPEZOIDALBEAMS OR5BEAMS ARE INCREASINGLYPOPULAR BECAUSE OFTHEIRAESTHETICAPPEAL4HEYARENOTSUITABLEFORPIERSEGMENTSWHERETHENONCOMPOSITEBEAMISREQUIREDTORESISTSIGNIFICANTNEGATIVEMOMENTS
&IGURED DEPICTS AUNIQUE SOLUTIONWHICH USES AHYBRID COMBINATIONOFPRECASTANDCASTINPLACECONCRETE0RECAST)BEAMSACHIEVEASLENDERLIGHTLOOKINGMIDSPANELEMENTANDARECOMBINEDWITHCASTINPLACECONCRETEBOXBEAMSATTHEPIERSWHERECOMPRESSIVEFORCESCAUSEDBYNEGATIVEMOMENTSREQUIREA LARGEBOTTOMFLANGE7HILETHISSOLUTIONHASTHEBENEFITOFIMPROVEDSECTIONPROPERTIESTORESISTNEGATIVEMOMENTSATTHEINTERIORPIERSCONSTRUCTIONISMORECOMPLEXANDLENGTHYTHANFORMORECONVENTIONALPRECASTCONSTRUCTION(OWEVERWHERESTRUCTUREDEPTHISSEVERLYRESTRICTEDASECTIONLIKETHISHASPROVENTOBEANECONOMICALSOLUTIONFORSEVERALBRIDGES
"Y CONSIDERINGSPLICEDBEAMS THE DESIGNERHASMORE FLEXIBILITYTO SELECTTHEMOSTADVANTAGEOUS SPANLENGTHSBEAMDEPTHSNUMBER AND LOCATIONSOFPIERS SEGMENTLENGTHS FORHANDLINGHAULINGANDCONSTRUCTION ANDSPLICE LOCATIONS!SDISCUSSEDIN3ECTIONACOMMONLYUSEDSPLICINGTECHNIQUEISTOPOSTTENSIONASERIESOFBEAMSTHATARESIMPLYSUPPORTEDONPIERSORABUTMENTS4HISACHIEVESCONTINUITYFORDECKWEIGHT ANDSUPERIMPOSED LOADS)N ADDITION TO THEENHANCED STRUCTURAL EFFICIENCYOFTHISSYSTEMPOSTTENSIONINGCANBEUSEDTOASSURETHATTHEDECKISSTRESSEDBELOWITSCRACKINGLIMITWHICHIMPROVESDURABILITYCONSIDERABLY
!NOTHERFEATUREOFSPLICEDBEAMSISTHEABILITYTOADAPTTOHORIZONTALLYCURVEDALIGNMENTS"YCASTINGTHEBEAMSEGMENTSINAPPROPRIATELYSHORTLENGTHSANDPROVIDINGTHENECESSARYTRANSVERSEDIAPHRAGMSSPLICEDBEAMSMAYBECHORDEDALONGACURVEDALIGNMENT4HISISSHOWNCLEARLYIN&IGURETHATSHOWSTHE2OSEBANK0ATIKI)NTERCHANGEIN.EW:EALANDWITHAFTRADIUS
{->>}ii>`
-ViV>
8/-*-{/ivi>{->>}ii>`-ViV>
&IGURE4HE2OSEBANK0ATIKI
)NTERCHANGE.EW:EALAND
0IERSEGMENTSWITHSTRONGBACKS
3PLICEAT0IER
3PLICED"EAM5NITE