ABSTRACT
Abstract................................................................................................................... 125 Introduction............................................................................................................ 126 Lenticular.Truss.Bridges........................................................................................ 126 The.Patents.of.William.O..Douglas........................................................................ 128 Bridge.Production.by.the.Berlin.Iron.Bridge.Company......................................... 131 Summary.of.Surviving.Bridges.............................................................................. 133 Analysis.of.Surviving.Bridges................................................................................ 136
Aspect.Ratio.(L/H)...................................................................................... 136 Number.of.Panels........................................................................................ 137 Vertical.Web.Posts...................................................................................... 138 End.Post-Lower.Chord.Connections........................................................ 139 Lower.Eye.Bar.Chords................................................................................ 139
Summary................................................................................................................ 141 References............................................................................................................... 143
Of.the.estimated.five.to.six.hundred.lenticular.iron.truss.bridges.built.by.the.Berlin. Iron. Bridge. Company. over. a. twenty. year. period. from. about. 1880. to. 1900. only. about.50.bridges.remain..Extant.bridges.are. located. in.Hew.Hampshire,.Vermont,. .Massachusetts,.Connecticut,.Rhode.Island,.New.York,.New.Jersey,.Pennsylvania.and. Texas..Over.the.past.5.years,.the.author.has.visited.all.but.two.of.the.extant.bridges.and. documented.their.geometry.and.condition..Some.of.the.bridges.are.still.in.service,. some.are. closed. to. traffic,. some.have.been.adapted. for.use. as.pedestrian.bridges. and.some.are.in.storage.awaiting.a.final.decision.on.their.fate..These.bridges.are.an. example.of.a.special.type.of.catalog.bridge.available.in.the.mid.to.late.19th.Century.. The.bridges.represent.a.unique.design.during.a.time.when.many.bridge.companies. were.competing.for.contracts. in.a.highly.competitive.market..These.bridges.were.
