tm 5-273 25 ton ponton bridge model 1940

7/30/2019 Tm 5-273 25 Ton Ponton Bridge Model 1940

1/209Publ

icDomain,Google-digitized

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48.

angedasfollows:

ead:25-TONPONTONBRIDGE,

NPONTONBRIDGE,MODEL1938.

nbridge,model1940.

bridge,model1936.

93-100

ding10,1-102

1

se* * * lightpontonbridge.

cityofthebridgeis 25tonsitmaybe rein-

ankloadsupto45tons.

C1,May26, 1943.)

nit.a.Theprincipalcomponentsof

rtrestleswithtrestlebracing,twelvepon-

maticfloats,andthenecessarybalkandchess

eumaticfloatsaresupplied forreinforcing

desfor210feetofunreinforcedbridge,

pneumaticfloats,iffour trestlesareused.

esanadded180feet offloatingspan.

sufficientfor157feetofbridger einforced

dfourtrestlesareincluded;eachadditional

etoffloatingspan.

C1,May26, 1943.)

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.

__

ddlesin carry-


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TONBRIDGES

g Medium(SB-ton)pontonbridge Truck

rut,bracing-.

gunwaletype-

t,22-hpmotor.

withhook

essories


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yofloading.a.Pontonload.One

es.(Seefig.1.1.)

May26,1943.)


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TONBRIDGES

abutmentspan,onehingespan,anextra

eassault boat.(Seefig.2.1.)

C1,May 26,1943.)


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lebayswithallaccessories.(Seefig.3.1.)

C1,May26, 1943.)


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TONB.RIDGES

ebracing.a.General.Trestle

the stabilityoftrestlespanssubjectedto

rlyinstalleditincreasesthecapacityofa

mprovingitsstability.Themannerin

edis governedmainlybythestabilityofthe

ebracingunstablefoundation.

C1,May26, 1943.)

nswherelargesettlementsofindividual

desirabletomakeanintegralunit ofeach

efig. 7.1.)Thisiscalledtripodbracing.

cingstrutsfrom thetopofeachtrestle

e sides.

onswherelittlesettlementisprobable,

ectadjacenttrestleswithsinglediagonal

tis desirabletoconnectadjacenttrestles

ng.(Seefig.7.3.)Where4or more

essarytobracealternatespansonlywiththis

gpiersofeachpair oftrestles.

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ebracingsemistablefoundation.

C1,May26, 1943.)

ebracingstablefoundation.

C1,May26, 1943.)

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TONBRIDGESC1

mis nearthetopofthe trestlecolumns,

eusedinorder toprovidelateralstability.

onsistofstrutsfromthetop ofthetrestle

sides;in hardgrounditmayconsistof

cing)orasingle diagonalstrutbetween

hetrestletransom.

heendtrestle.Theendtrestleonany

dfromthe shore.Eachanchorpostis

rth auger.Abracingstrutisfastened

bottom,andtothetrestlecolumnnear

edbymeansoftrestle-bracingclamps.(See

houldbe anchoredsecurelytootherposts

showninfigure7.4or tonaturalorpre-

heendtrestleis furtherbracedinatripod

ndbracingstrutfrom thetopofeachcolumn

ebridge.(See fig.7.1.)

restles.(a)Unstablefoundation.

nsareunstable,eachtrestleanditsbracing

aunit.(Seefig.7.1.)Whenthis typeof

gstruts formanangleofabout30 with

ge.Thefirststepis theassemblyofthe

e.The strutshoeshankisinsertedinto

utandthestrut shoepininsertedandfast-

eendofthebracingstrut isthenplaced

nterthesoil,and theupperendofthe

t thetrestlecolumntodeterminewhere

astenedtothecolumn.Atrestle-bracing

thecolumn,andthe strutportionofthe

boutthebracingstrut.This permitsthe

thestrutwhilethestrut isturnedby

ertedinto theholeattheend. Thestrut

ntothegrounduntil itreachesafirm

columnandstrutclampsare alternately

obtainafirm bearingbetweencolumnand

e-bracingclampsaretightenedaround

circumstancesisX-bracingusedbetween

ongitudinalstabilitywhenthereis apos-

ing morethanafoot.

.Thenecessarybracingisprovidedby

span.(See fig.7.2.)


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11/209

n use.

C1,May26, 1943.)

utshoeand strutintoground.

C1,May26, 1943.)

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TONBRIDGES

henusinglongitudinalX-bracingwith

k andchess,itisnecessarytoclampboth

strutontheoutsideof thecolumns(side

heoppositeendsofthe secondstruton

ingclampinuse.

C1,May26, 1943.)

hecolumnrespectively.Positionofthe

otheheight ofthecolumnsdetermines

rutwill beclampedtotheoutsideofthe

beclampedto theinside.(Seefig.7.3.)

sbothendsofonediagonalbracemaybeclamped

ndsoftheseconddiagonalbraceonthe insideofthe

es.Theshoesoftheendtrestleare pre-

steningeachshoeofeachshorewardtrestle


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heanchorpostsorto naturalorprefabri-

ditionswarrant,alltrestleshoesshould

ratherthan manilaropeshouldbeused,

aybetightenedmorereadilybymeansof

ablegrips.

eshoeanchorlines.

C1,May26, 1943.)

e,passoneendof thecablethroughthe

oeandfastenthefree endtothestanding

eecableclips,spacedabout3inchesapart.

sshouldbearagainst,thestandingpart

enedwith aspecialopen-endwrench.

nchorcablearoundtheholdfast,place

endandoneon thestandingpartofthe

ogripswiththe ratchetchainhoist.Fasten

their approximateposition.Tightencable

ghtencableclips.Removeratchetchain

figs.7.7 and7.8.)

C1,May26, 1943.)


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TONBRIDGESC1

onatnight.a.Limitationsofequip-

notwelladaptedforabridge tobethrown

ithoutknowledgeoftheenemy,andbeforea

blished.Becauseofthenatureofthetrans-

assemblyatthebridgesitecreatesconsider-

trestleshoeanchorlinewithratchetchainhoist.

C1,May26, 1943.)

(fer&n^ss.^-Constructionofthebridge

generallythesame asconstructioninday-

difficulttoincorporateindividualpon-

eduringdarkness,althoughtheprocess

hiefdifficultyarisesingettingthe equip-

ts,in placingandhandlingcablesandlines,

nddirectingitto thefarshore.Thesediffi-

dthofstream,forceof current,anddegree

ndrapidconstructionatnightdepends

organization,closecontrol,andadequate

earsal.

eanimportantrivercrossing,construc-

ethoroughlyrehearsed.Rehearsalshould

astreamassimilarto thestreamtobe

oopsparticipatinginthe rehearsalmust

onstructthebridgeforthe actualcrossing.

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thebridgemustbe constructedinaman-

edin theactualcrossing.Therehearsal

erealconstructionaspossible.

ailedreconnaissanceofthebridgesite

ours ofdaylightbytheofficersandkey

whoareto supervisetheconstructionat

fthebridgesite, eachpartssite,unload-

reamanddownstreamanchorsareselected.

ningtherouteofapproachandtrafficcir-

e.Ifsecrecypermitsthesepoints should

peorsignal cloth.Ifthebridgeor parts

aded,a smalladvancecrewshouldbesent

daylighthours.Ifthisis notpossibledue

ementsmustbemadeforpreparingthe

onstructionstarts.Membersoftherecon-

morizetheappearanceandcharacteristicsof

ndaylightand takeallpossiblemeasures

henightconstruction.

Duringconstructionatnighttelephone

henearshore,far shore,constructionendof

site isessential.Asingleflashlight,pro-

telight,canbe usedonthefar bankto

rectionandalinementof thebridge.Sim-

howthepositionsof upstreamanddown-

nshieldedflashlightstoaidin the

used.Ifavailable,luminousmarkersor

orpiecesofclothare usefulinoutlining

utesof approachtotheunloadingpoints,

ndtheheadsofpicketsandconnectingpins.

.Althoughactualconstructionwill

erthe needforsecrecyhaspassed,lights

teshouldbeheldto aminimum.

C1,May26, 1943.)

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TONBRIDGESC1

normallyplacedat themiddleof

C1,May26, 1943.)

erailsection.

mpsshouldbeplacedhandle sideup.

C1,May26, 1043.)

onofsite.Thepreparationofasite

dependsuponthelocation.Everyeffort

tes,aboveor belowthebridgesite,atwhich

withoutpriorpreparation.Fromtwoto

ed.Whereno suitablenaturalsitesexist,

Figure23 isconsideredtypicalofthe

uired.Itisnecessarytoprovidea cleared

and eachpartsbuildingsite,properap-

nd,androadconnectionstoeachclearedarea.

orkingpartyrequired.Theworking

fromtheabutmentshouldincludeall

peditiousconstructionbythemethodofsuc-

rkingpartyconstructingapartshouldbe

mall operationsnecessarytoconstructthe

uipmenttothedispatchof thecompleted

usualfour-boatthree-baypart,anengi-

dealwork group.

C1.May26, 1943.)

ncorporationintothebridge.

ructionofapart.Ingeneral,thecon-

mplishedinthesamemannerasthatofa

ewherethe methodofsuccessivepontons

k,chess,siderails,andsiderailclampswith

tiontothebridgeare loadedonthepart


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partssite.Materialcarriedonthepart

tingthenextpart. Thecompletedpartis

byananchorsection.Theworkingparty

ructionofanadditionalpart.

obridge.Aspartsare completed,

anchorsectionandmovedtothemaneuver

erpontons,orpowerboats.Upstream

art isplacedinextensionofthe bridgeby

.Necessarydownstreamanchorsarecast

ts.Thepartisthenconnectedtothe bridge

e bridge.Thelocationofpartssites

gefacilitatesthesafehandlingofparts.

thelong bridgemaybegreatlyincreased

rombothbanksandmakingthejunction

gbalkwith detachablestirrups.Infact,

erule inconstructinganybridgeappre-

.

ral.Thebridgereinforcedbyinsert-

hfloatingspan,fourextratrestlebalkin

xtrapontonbalkin eachfloatingspan,asin

dsin theneighborhoodof45tons.Inits

nerallybeaprobleminclosingthe gapleft

forcedfloatingspanhasbeenput in.The

topermitinsertionofa reinforcingponton

thattheunsupportedlengthofpontonbalk

tivelygreat.

bridge,theunsupportedlengthofbalkbetweenadja-

telyonefootmeasuredbetweenoutsideedgesof

tons.

crossthegap isappreciablygreaterthan

utilizedinclosingthegap.

pneumatic-floats. (a)General.

aybereinforcedis byinsertinga12-ton

hfloatingspan,andincreasingthenumber

atingspansto14 and12respectivelyasin&

dgewillcarrytankloadsof approxi-

fig.28.1).Thepneumaticfloatcanbe

by useoftheinflation-deflationmanifold


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TONBRIDGES

bridge),attachedtoan aircompressor.

uldnotbegreaterthan iy2poundsper

tthefloat firmlyresistspressureapplied

Additionalpressureaddsnothingtothe

mayblowoutbulkheadsor causeleaks.

emperatureshouldbeanticipated;floatsin-

rebecomeoverinflatedifthe temperature

urelyclosedwhenthedesiredpressureis

neumaticfloat.

C1,May26,1943.)

structure.Superstructureisplaced

reventwearingof thefloatfabricandto

nderload.Superstructureforeachfloat

soms(timberplanks3by 12inchesby7

ontonbalk)whichareplaceduponthein-

re 28.2.Floatsillsarestrappedinto

ps.

east16menarerequiredto pickupa

water.Itshouldbe carriedbytheD-rings

houldbe heldwellofftheground,as

berizedfabric.

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mbly.

C1,May26, 1943.)


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TONBRIDGES

dge.

floatshouldbeplacedundereach

ndsecuredtothebridgedeckwith

oat,asshownin figure28.3.

securedwith ropelashingsbe-

e floatandthehandrailsor

s.(Seefig.28.4.)Afloatshould

centerpontonofa hingespan

pedtobridgedeck.

C1,May26, 1943.)

sthegapistoo smalltopermit

oat,oneor twocentertubes

ybeusedunderthatspan. (See

einforced.Inconstructionofthe

s,fullyinflated,areinserted

beforethe balkarelowered

ers.

dges.Inthereinforcementofexist-

esarepreparedasdescribed

sareplacedon theirsides.Upon

oatsarepartlydeflatedsothat


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nforcedwithpneumaticfloats.

C1,May26, 1943.)

besfrompneumaticfloatsusedunderspanwhichclosesthegap.

C1,May26, 1043.)


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TONBRIDGESC1

hespan. Afterthefloatsare

illsare turnedupandthefloats

pressure withanaircompressor.

C1,May26, 1943.0

settlementofthe trestles,andperiod-

use,trestle-bracingclampsshouldbeloos-

easeanystressesintroducedin thebracing

etrestles.

reinforcedwithpneumaticfloats,the

ovedfromunder thespanswhennecessary

ass underthebridge.Pressureinfloats

rly.Ifnecessarytheaircompressorcanbe

addairto thefloatswithoutremovingthem.

C1,May26, 1943.)

Inanemergencysinglepneumatic

expedientforferryingpersonnel.Thecentral

ndchesslaid onthefloorofthe float.About

s)canbecarriedon onefloat,20menstrad-

e float.Machinegunsandmortarscan

C1,May26, 1943.)

al.

oatsmaybeusedtoreinforceponton

pedientrafts.

C1,May26, 1943.)

Includedintheorganizationalequip-

panyarefour22hp outboardmotors

page.Fourattachmentbrackets

pontonequipage.

C1,May26, 1943.)

(1)General.Pontons,trestles,tres-

ss,sills,andmetalfittings mustbekeptwell

on,rusting,orrotting.Thisis particularly


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ntisstoredintheopenor usedinsaltyor

)Paint,olive-drab,lusterless,marked:

epaintingmarineengineerequipment.

tantpaint,containingcriticalmaterials,

orrefinishingwater-immersibleequipment.)

marked:"PaintFI"Primingcoat

minummarineengineerequipment.(This

aterialsandshouldbeusedonly forrepaint-

ter-immersibleequipment.)

ed:"PaintF-II"Primingcoatfor

eengineerequipment.

"Paintcleanerandthinner''Mineral

epaintingengineerequipmentandthinner

hedin50-gallondrums.

t,marked"Paintetcher''H3PO4

galuminumalloyengineerequipment.

ainers.

r"asfurnishedis50percentphosphoricacidand50

rpartsofwateraremixedwith onepartof"paint

n.

removingoldpaint.

ndsteelpontonsandtrestles.Loose

erforeignsubstancesshouldberemoved

e brush.Cleaningbysandblastingisthe

ifsandblastingequipmentisavailable.

mentisused,sandremainingon thesurfaces

heapplicationofthepaint, Inadditionto

hor sandblasting,surfacesshouldbe

s(paintcleanerandthinnermentionedin

en receiveafinalrinsingin clean,unused,

aintedshouldnextbeetched.Thisetch-

hosphoricacidetchingsolvent(paint

ldremainincontactwiththe aluminum

dthesurfacesshould thenbewashedthor-

eelor aluminum)shouldbegiventwo

Afterpriming,the surfacesshould

aint(paint A).

,andotherwoodenitems.Allsurfaces

oroughlycleanedofalllooseorcracked


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TONBRIDGESC1

stanceswithawire brush.Woodensur-

coatsofprimer (paintF-II).Afterprim-

ceivexonefinishcoatofpaint (paintA).

ces.Brass,bronze,andothernonfer-

ptaluminum)neednotbepaintedbutshould

ucereflectionoflightto aminimum.

efirstcoatofpaintshouldbe applied

etionofcleaning.Allpaint whenapplied

oryfilmandsmoothevensurface,suitable

ndadhesionofsubsequentcoats.Paint

spray,butifappliedbyspray, eachgallon

byanadditionalquartofmineralspirits

.Nopaintshouldbe appliedtosurfaces

moisturecondensation,norduringrainy

ngpaintedis amplyprotectedagainstthe

ileanypaintingis beingdone,thetempera-

ontactwiththe paintsurfaceshouldbe

F.Also,allpaint,whenapplied,should

metemperatureasthesurfaceon whichit

asbeencommencedonanyportionof the

ngoperation,includingprimingcoatsand

f thework,shouldbecompletedassoonas

east24hoursshouldbeallowedto elapse

nishcoats.

pacity

ctriclantern

ning:

ilarope,7-inch,snatch.

5-ton

e


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ingContinued.

steel,250'

end,singlehead,10"(Crescent)

gunwaletype

t,22hp.motor,ponton25-ton

okandeye

n

essories

nutl

completewithemergencyrepairkit,and

5-ton

3-ton,2 hoistsinchestset..

t

est

ol

6-volt

on,fourhosecomplete

ed

5-ft

ction

55G.P.M.,completew/25'\%"discharge

and spannerwrench

9 plowsteeldo_.

odenbalk,25-ton

andinches

st)


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TONBRIDGESC1

Steelpontonsarebeingmanufactured

s.Thesesteel pontonshavethesamegen-

mensionsasthealuminumonesbutweigh

dsmorethanaluminumpontons.Theirnet

1,500poundsless;thisdoesnot materially

apacity.

float.a.Descriptionoffloat(see

eumaticfloatis25feetlong,T1/^feetwide,

adeofrubberizedfabricandconsistsof

aremovablecentraltube.Eachtubeis

eumaticfloat.

C1,May26, 1943.)

s dividedbybulkheadsintoseparately

achmentsconsistofstrapsforholding

pstoholdthe centraltubeinplace,D-rings

r attachingbridlelines,andalife line.

ately525pounds.Ithasa buoyancyof

undswitha9-inchfreeboard,orofapproxi-

enfloatingwithnofreeboard.Whenthe

terfills thespacebetweenthecentraland

educedtoapproximately21,000pounds.The

scarryingcasewithdimensionsapproximately

mergencyrepairkitisincludedin each

ation.Thefloatisinflatedby useofan

ldattachedtoanair compressor.Themani-

ceivethehose fromtheaircompressor,a

lethoses,eachabout6 feetlongandeach

alvalve.Toinflatethefloat, attachtheair

anifold,openaircompressorvalvetoallow


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,turnmanifoldregulatingvalveto"inflate,"

ompartmentsbyturningthemcounterclock-

eachmanifoldhosetooneofthesevalves.

pneumaticfloatcanbeinflatedsimulta-

undedout atapressureofabout 1pound

ngpressureshouldbe iy2poundsper

tthefloat ceasestobesoftbutcontinuesto

essure.Thefloatcan beinflatedinabout

old.Floatsmaybe deflatedbyremoving

andallowingtheairto escape.However,

uldbedrawnoutwiththe inflation-deflation

oatseasiertopackin asmallspace.The

hesameas forinflationexceptthatthe

nifoldisturned to"deflate."

C1.May26, 1943.)


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TONBRIDGES

tleM2.a.GeneralThe25-ton

estlesimilaringeneraldesign anddimen-

tleMl describedinparagraph75.The

estleis approximatelythesameastheweight

).Followingisadescriptionofthe parts

rasit differsfromthealumimimtrestle.

NG

TED

ONS

stleM2.

(C1,May26,1943.)

everticalrowofholesin thecolumn

olumn.Theswiveledhangersontopof

tofchainhoistsis eliminated.Initsplace

echain-hoistsupportingbracketwhichcan

holesofthetrestle columnaccordingto

etisdescribedin/ below.

histransomconsistsofatubularsteel

olumnwell ateachend;insteadeachend


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columncanbeinsertedfromthe side.Two

softhis openingtogether(theydonot

mn).Twopinsareattachedtoeachendof

herearethreesets ofpinholesat eachend

insertedintheoutermostsetof pinholes,

f theratchetchainhoist.Thesecondpin

otherofthe tworemainingsetsofholes

nthetrestlecolumn,thussecuringthe

elattertwosets ofholesare5%inches

n thetrestlecolumnarespaced3%inches

ntcanbemade aswiththetrestleMl.

Theseshoesaremadeofsteel andare

Two1%-to3-tonratchetchainhoistsare

foradjustingtheheight ofthetransom.

sthe l^-tondifferentialchainhoist,and

trestles.

commercialtypehoistwitha12-foot

chaincanbeattachedso thatonlya

sthe load(capacity1%tons)orsothat two

ad (capacity3tons).Thehoistcanbe

er.Forusewith25-tontrestles,thechain

thusgivinganeffectivechain-hoistlength

ainhoistis attachedtothechain-hoist

bedin/belowandtheother hooktothe

nsomMl(or tothepinat theendofthe

heightof thetransom,slingtwohoists

ovetransompins,adjustheightoftransom

bothhoistsat thesametime),reinsertthe

s.Thehoists werenotdesignedtotake

ge; itisessentialthereforethatthey be

aged(withthetransompins inplace)

e bridge.Eachratchetchainhoistweighs

racket.Achain-hoistsupporting

atchetchainhoistto supporttheupper

hoistisused toadjusttheheightof the

39.1and39.2.)This bracketmaybe

mnsatanyconvenientheightabovethe

ldinplaceon thetrestlecolumnbyan

edtothebracketwithachain,through


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TONBRIDGESC1

C1,May1>6.1943.)


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stlecolumn.Aboatsnapattachedtothe

erted inthecolumnpreventsthepin from

areusedwiththe trestleMl,chain-hoist

beusedsincetheeffectivelengthofthe

ncapacity)isonly 6feetwhichisnot

wiveledhangerat thetopofthe column.

cingequipment.Followingisa

entsofthetrestle-bracingset:

.3).Thestrutis a22-footsectionofa

tha^e-inchholeanda !5/16-inchhole

allerhole permitsfasteningofthestrut

stheuse ofanordinarypicketasa handle

andstrutshoe istobe screwedintoorout

er.

cingstrut.

C1,May26, 1943.)

entlystrongforuseasbracing.Abuse,excessively

e strutforpurposesotherthanthe oneforwhichitis

geit.Ifnot handledproperly,thestrutcanbebem

achbracingstrutweighsabout125pounds.

a steelcastingwhichisfastenedtothe

shoepinwhenitis necessarytoscrewthe

hoeissoshapedthat itmaybescrewedinto

weighsabout15 pounds.(Seefig.39.4.)

tshoepin isusedtofastenthe bracing

providedwitha latchandisfittedwith a

tch fromworkingoutofthepin.When the

the strut,thestrutshoepin shouldbere-

ththelatchandboatsnap insertedintheir

tlossof thestrutshoepin.

Theclampconsistsoftwocaststeel

iveljoint.Thelargerofthe twoclampsi?

mnoranchorpost, andthesmalleronet


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TONBRIDGES

pweighsabout18 pounds.(Seefigs.

6).Theanchorpostisa 5-footsection

hichhasaspiral flangefastenedtoone

%6-inchholetopermittheuse ofasteel

wingthe postintoahole madewiththepost

eandstrutshoepin.

C1,May26,1943.)

oftheanchorpost issuchthata bracing

withatrestle-bracingclamp.Theanchor

ermituseoftrestle-bracingclamps,and

elytootherpostsdriveninto thegroundas

rpostsareused toanchortheendtrestle,

ytoo hardtopermituseof strutshoes.A

esof stakesmaybesubstitutedforthe

postweighsabout100pounds.

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acingclamp.

C1,May26, 1943.)

a hand-operatedaugerprovidedfor

theanchorpostisset.The augerisabout

out15pounds.(Seefig.39.7.)

Thisis%-inchsteelcable,usedto pre-

slipping,particularlywhentheyrest on

t.

C1,May26, 1943.)

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TOXBRIDGES

ndwellauger.

C1,May26, 1943.)

ableisfastenedtotherings ofthetrestle

efabricatedholdfastonshore(orto the

ghtenedwitha ratchetchainhoistand

withcableclips.(See fig.39.8.)

oeanchorline.

C1,May26, 1943.)


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nordinarysnatchblockfor%-inch

heshoreendof thetrestleshoeanchorcable.

anchorcable.(Seefigs.7.7and 39.9.)

platewith holesdrilledintoit fordriv-

hpicketisl1/^ inchesindiameter,40inches

endtofacilitateremoval.Thisprefabri-

ch.

C1,May26, 1943.)

chorthe trestleshoeanchorlineonthe

romtrestlebracingsets,reliancebeing

visedholdfastsandon theanchorpoststo

eweighsabout25 poundsandeachpicket

heentireholdfastweighsabout160 pounds.

tedholdfast.

C1,May26, 1943.)

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TONBRIDGES

ig.39.11).Thisisthe hoistusedto

estletransom.Itisused totightenthe

Fortightening,itis fastenedtothecable

s,one gripattachedtothefreeend and

fthecable.(Seefig.7.8.)Beforetighten-

ainhoist.

C1,May26, 1943.)

oselyfastenedin place.Afterthecable

defastandtheratchetchainhoistsand cable

2).Thiscablegrip(or "comealong")

h grippingsurfaceandisusedto

sttobe attachedtothewirecablefor

psarerequiredforthis, unlessthefree

neye,whenonlyonegrip issufficient.

3).Cableclipsfori^-inchwireare

osectionsofwirecable together.Twoor

herspacedabout3 inchesapart.Thegrip

ainstthestandingpartofthe cable.(See

dbefastenedinto placelooselybeforethe

ecableis tautthey-aresecurelyfastened

wrench.

g.39.14).Thisisacommercialtype

ustablewrench,10incheslong.Itisused

eclips.

C1,May26, 1943.)

PublicDomain,

Google-d

igitized

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oogle


37/209

p.

C1,May26, 1943.)

p.

C1,May26, 1943.)

escent,10-inch.

C1,May26, 1943.)


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38/209

TONBRIDGESC1

MODEL1938

93-100

ing101-102

1

XIItoXXVIcoverthe10-tonponton

dgeis similarindesignto the25-ton

nstruction.Itisdiscussedhereonlyinso

-tonbridge.

useofthisequipageisto providea

ssingformostvehiclesof aninfantry

malcapacityofthebridgeis 10tons,it

mmodateloadsupto20tons.

sign.The10-tonpontonbridgedif-

nbridgeas follows:(Seefig.40andfig.47.)

he followingissubstitutedtherefor:

ighter.

rs areusedperfixedandper hingespan,

gersper floatingspan.

s9 feet10inches.

employed.

n,trestlespan,andhinge spanis15

gspanis 15%feet.

sbridgeequipmentmaybe issuedto

asubstitutefor thepontonbridge,pneu-

arenormallyequipped.Pontonsforthis

manufactured.Existingequipageiskept

quired.


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39/209

C1,May26, 1943.)

E

partsof10-tonpontonbridge equipage

gpartsof25-ton bridgeequipagedescribed

aturally,thesepartshavesmaller


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40/209

TONBRIDGES

redesignedforalighter load.10-tonbridge

from25-tonequipage,arebrieflydescribed

mponton.Thepontonis28feet long,

2feet8inchesdeep.There arenocapstans

hpontonis providedwith32ratchet-type

uckle-typesparebalkfasteners.Thepon-

onbridge,model1938.

C1,May26, 1943.)

y1,450poundsandhasatotal displacement

sedasa ferrywithanoutboardmotorit

mately50menwithfullequipmentbesides

ngtablegivestheponton displacements

eboards:


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41/209

Eachpontonisequippedwithtwo anchors,

athooks,sevenoarsandoarlocks,andone

calwith25-tonpontonaccessoriesexcept

undsandoarsare 13feetlong.

elve-tonpneumaticfloatsaresupplied

bridge.Thesefloatsareidenticaltothe

onpontonbridge.(See par.74.1.)

The10-tontrestleMl(aluminum)

(steel)aresimilartothe corresponding25-

nd 75.1.)Theassembledtrestleless

50pounds.Theheightof thetrestlesis15

hcentertocenteroftrestlecolumnsis

ttachmentsonthetrestle transomtubeare

thepositionofthe8 pairsoftrestlebalk

Two extrabalkcanfitin theinterval

hatitispossibleto fit15pairsof trestle

, eachtrestlespanmaybereinforcedto15

tchetchainhoistsareused withboth

stsupportingbracketswiththetrestleM2

nches.

13feet10incheslongby9 incheswide

chesby24inches.

nches.

bulartype)13feet10incheslong

2inches.)

chesby27inches.

oradjustingtheheightof10-tontrestle

beconnectedsothat asinglestrandofchain

acityseefig.39.2).Inthismannerthe

ain canbeutilized.

bracket.Thisbracketisnot necessary

sincetheratchetchainconnectedsinglyis

wiveledhungerat thetopofthe trestlecol-

edwiththe10-tontrestleM2.

tle-bracingpartsforthe 10-tontrestles

e-bracingpartsfurnishedwiththe 25-ton


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42/209

TONBRIDGESC1

clampsareslightlysmallersothatthey

rof the10-tontrestlecolumn.

esmallerin diametersothat10-ton

lfitthem.

alk,ponton.Dimensions4inchesby

es.

riedbytwomen).

ons4inchesby6inchesby15feet4%

nds(carriedbytwomen).

%inchesby11%inchesby12 feet.

edbyoneman).

ns2%inchesby5%inchesby 12feet.

nchesby7%inchesby13feet.Weight

omen).

lclamps.Dimensions14-inchjaw.

ght,16pounds.

unds.

a.Outboardmotors.Seeparagraph

graph70.

h88.

OADING

es.a.General.Theequipagefor

portedonsixsemitrailersdrawnby5- to

ndfourtwo-wheelponton-typetrailers

otrucks.(Seefigs.48and 49.)Eachunit

s,twotrestleloads, andtwoabutmentloads.

usedtoconvertthesemitrailersinto four-

ilerscanthenbemaneuveredoverun-

rmediumtractors.Formovementover

wo-wheeltrailersmaybedetachedfrom

thetractors.

al,thesemitrailerusedtotransportthe

thatusedtotransportthe25-ton bridge

ailer thereisnodepressionin thetrailer

mpartmentattherear, thereisaremovable

ailerwhichisused fortoolsandauxiliary


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43/209

nchorswithcables,oarlocks,pumps,and

onsplacedoneontopof theotherarethe

er.Thepontonsare heldsecurelyinplace

t byreel-type,ratchet-operatedcabletight-

der)hasa protectingsheathof%-inch

additiontherearefourshorterload binders

e balkandchessofthepontonload inplace.

dfromthe bottompontonbysixspacer

truckandtwo-wheeltrailerwithabutmentload(lU-tonponton

C1,May26, 1943.)

ocksocketsonthetopponton gunwales,three

atedpumpoperatestwohydraulicjacks,

thesemitrailer,whichelevateorlowera

ponwhichthepontongunwalesrest.The

erearendsofthe pontonstofacilitateload

onsby hand.

etwo-wheeltrailerhasa rectangular-

y,andanadjustable-lengthdrawbar,suj

Auxiliarylashingringsareweldedto th

tm 5-273 25 ton ponton bridge model 1940

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