The “Ponte di Muro” bridge on a disused railway line at

93

Friulian Journal of Science 14. 2010, 93-109

1 The Pontebbana railway line1.1. Historical outline. The line. Thehistorians of the railway networkwhich has been crossing the Alpe-Adria region for the last hundred andfifty years have produced over thedecades a large and well-detailedbody of research, also serving as aprecious and comprehensive techni-cal bibliography.

A contemporary of the famousAustrian lines “Transalpina” (Trieste-

Jesenice-Ceské Budejovice) (AA.VV.1996, Petronio 1997) and “Südbahn”(Trieste-Semmering-Vienna) (Ram-pati 2002, AA.VV. 2007), the Ponteb-bana railway line between Udine andPontebba (Bortotto 1979, Roselli1979, AA.VV. 2006) deserves an im-portant place in 19th-century railwayengineering, also by virtue of its spec-tacular and audaciously-accom-plished crossing, by its 5th section, ofthe orographically complex “Canal

The “Ponte di Muro” bridge on a disused railway line at Dogna, Udine, and its recent conversion to cycle use

A L E S S A N D R O C O C C O L O *

* CP Ingegneria, via Roma, 274, 33013 Gemona del Friuli (UD), Italy.E-mail: [email protected]

Abstract. This article illustrates the rail-to-trail conversion of a truss bridge known as“Ponte di Muro”, located near the village of Dogna in the Julian Alps. The bridge waspart of the disused Pontebbana railway line which has now been converted to accom-modate the new “Alpe Adria” cycle trail. The paper includes a short history of the rail-way line, with particular reference to the bridge, the main technical details of the pro-ject and a description of the different phases of its execution.

Key-words. disused railway line, cycle route, metal bridge.

•Rivista GFS n. 14-2010 24-10-2011 12:37 Pagina 93

A . C o c c o l o

94

the life of the population of the valley,who contributed to the greater partof the 3000-strong workforce.

The first train pulled in at Ponteb-ba railway station, by the Austria-Italy border, at 3 pm on 12 July 1879,while the line was officially openedon the following 25 July, when regularUdine to Pontebba services started.On the other side of the border, theconstruction of the “Rudolphsbahn”line, linking Pontebba/Pontafel toTarvisio and to the Austria-Hungarynetwork (24.9 km), started off only inApril 1877. However, due to themore favourable orographic situationof the Fella valley between Pontebbaand Camporosso, work was complet-ed by October 1879. The internation-al line Udine-Pontebba-Tarvisio wasofficially dedicated on 30 October1879, and the event was largely re-ported by the press (Roselli 1979).

A crucial turning point in the de-velopment of the line was the re-placement of steam with electric trac-tion, as part of the electrification plan

Figure 1. Workers engaged inthe construction of a tunnel(archive Sorgato A. & Brusa-dini S.).

del Ferro”, the narrow and ruggedvalley of the River Fella between thevillages of Chiusaforte and Pontebba.

The construction of the line wasapproved by Law no. 896 of 30 June1872, following am agreement signedby the Italian Government and RomeBanca Generale on the previous 6May. It was designed by engineersCesare Bermani and LodovicoRichard on the basis of a feasibilitystudy written in 1857 by AlessandroCavedalis. The construction phase,supervised by engineer Giuseppe Oli-va, took place between 1873 and1879 (Marinelli 1894) and was divid-ed in 5 sections: Udine-Gemona,Gemona-Stazione per la Carnia,Stazione per la Carnia-Resiutta (7900m), Resiutta-Chiusaforte (8102 m),Chiusaforte-Pontebba (12058 m ofwhich 4311 m curvilinear, with twocrossings of the River Fella by daring-ly-designed metallic bridges)1. Theconstruction of the 4th and 5th sec-tions, conducted roughly between1877 and 1879, completely changed


The “Ponte di Muro” bridge on a disused railway line at Dogna

95

of the Italian railway networklaunched by the Fascist regime in1932-1933. The first electrically-pow-ered train ran on the line on 16 Sep-tember 1935, while the official inaugu-ration ceremony took place on the fol-lowing 28 October. The estimated costof electrification was of around 1 mil-lion lire per kilometre. During electri-fication work the line was substantial-ly refurbished: the tracks, the metallicbeams of bridges, the blockage andsignalling apparatuses were radicallymodernized (Bortotto 1979).

In its original version (Udine-Pon-tebba) the Pontebbana rail line had alength of around 68.3 km with a max-imum gradient of 1.6%, and was clas-sified as a 2nd-grade, single-trackline, with a capacity of 60 axes.

The length of the line became of93.2 km at the end of World War I

when it merged with the Pontafel-Tarvis line, and the gradient rose inparts of the line to 2.2%.

Construction costs were of440,000 lire/km for the Italian por-tion, and of 430,000 lire/km for theAustrian portion. However, if webreak down the costs between thefirst three sections of the line (Udine-Resiutta) and the last two (Resiutta-Pontebba), it appears that the 4thand 5th sections had a much highercost per kilometre, equal to around850,000 lire/km.

Main features. If on one hand thePontebbana line was, on the whole,characterized by a relatively modesttransport capacity, as is to be expect-ed by a mountain railway, on the oth-er its individual structures (bridges,viaducts, tunnels, retaining walls,

Figure 2. The longitudinal profile of the Udine-Tarvisio line (Roselli 1979). The gradient isindicated in the bottom row, the top row shows the progressive distance measured fromUdine station.


A . C o c c o l o

96

bank protection structures, all ofwhich were abundantly representedin the mountainous portion of theline) were, and still are, a remarkableengineering feat.

Table 1 summarizes the many dif-ferent structures comprised in theoriginal Udine-Pontebba line andwhich were mostly concentrated in its3rd, 4th and 5th sections.

Stations and crossing keeper’s cot-tages display very different architec-tural features depending on whetherthey originally belonged to the

Udine-Pontebba or Pontafel-Tarvisiolines. In the former case, they arebuilt in a typically northern-Italianstyle with a small eaves overhang andhave an altogether more anonymousappearance; in the latter case, theyare very Alpine-looking and charac-terized by a large use of exposedstone (Bortotto 1979). Metallicbridge designs, on the other hand,following the extensive moderniza-tion work carried out on the line inthe first half of the twentieth century,precisely correspond to the rigorous

Figure 3. Examples of some ofthe original structures of theline (AA.VV. 2010). Top right,the bridge on the River Fella atChiusaforte, top left the bridgeover the Rio Potocco. Bottom,the spectacular viaduct over theRiver Dogna, which tragicallycollapsed in 1968. As shown bythe photographs, the same trussdesign was used with all struc-tures. In the 1930s when theline was electrified and struc-turally reinforced, existingbeams were replaced and stan-dard Italian Railway designswere adopted depending onspan lengths.

Table 1. Types of structures in the original Udine-Pontebba line (Roselli 1979).

Type of structure number total length [m]

Bored tunnels 28 5,673Artificial tunnels 5 565Masonry bridges and viaducts 16 1,551Steel bridges and viaducts 11 820Retaining walls over the structure 12,592Retaining walls under the structure 3,180



97

standardization which had been im-posed at the time by the Italian na-tional railway company, Ferrovie delloStato. Accordingly, four bridge de-signs were used on the line, depend-ing on the length of the span:– girder bridges with twinned gird-

ers, for modest spans;– plate girder bridges, for longer

spans;– truss bridges with the deck sitting

on top or at the bottom of thetruss, and unconnected sides(pony trusses), for very long span;

– truss bridges with the deck sittingon top (deck truss) or at the bot-tom (through truss) of a box truss,also for very long span.It is not easy to single out an indi-

vidual structure as the symbol of theUdine-Pontebba line. In my opinion,there are two bridges that could as-pire to such title: the iron viaduct onthe River Dogna (progressive dis-tance 60 km + 986 m from Udine)and the “Ponte di Muro” (Masonry

bridge) situated a few miles more tothe north (prog. dist. 63 km + 868 mfrom Udine).

The Dogna bridge collapsed a fewyears before its one hundredth an-niversary on 16 September 1968, whenthe river overflowed with disastrousresults. It was replaced by a muchmore anonymous structure in pre-stressed concrete with five spans in-stead of the original four (Bortotto1979). A description of that tragicevent lies beyond the scope of this ar-ticle; in fact, an adequate discussion ofthe history of the Dogna bridge wouldcall for a separate treatise, also in con-sideration of the structural damagethat it suffered from allied bombingraids in 1944-1945 (D’Aronco 2008)and from an act of sabotage by the re-treating German army in May 1945,when one of its two metallic centralspans was destroyed (AA.VV. 2006).

The “Ponte di Muro”, on the oth-er hand, has survived unscathed.Towering 40 metres high above the

Figure 4. Examples of metallicbridges on the Pontebbana railline (years 2007-2008). Topleft, the small bridge over RioConfine with twinned girders(on the municipal border be-tween the villages of Dognaand Pontebba). Top right, thebridge on Rio Pontuz withplate girders (Dogna). Bottomleft, the pony truss bridge“Ponte Peraria”. Bottom right,the through truss bridge“Ponte della Chiusa” (Chiusa-forte).


A . C o c c o l o

98

river bed, it has lived through ruinousfloods, two world wars and an earth-quake, finally having to bear the hu-miliation of being abandoned on 12July 1995, when the 5th section of thePontebbana line was closed to traffic.On account of this, and also on thebasis of the information detailed inthe following chapters, it could wellbe awarded the title of “Symbol ofthe Pontebbana line”.

1.2. The Ponte di Muro bridge. Tech-nical characteristics. The bridgestands between the northern portal of

the first “Ponte di Muro” tunnel(330+16=346 m) and the southernportal of the second “Ponte di Muro”tunnel (365 m). It constitutes thethird and final crossing of the RiverFella within the “Italian” section ofthe Pontebbana line, after the bridgeat locality “Peraria” between Resiuttaand Chiusaforte and the bridge at lo-cality “Sclusa”, just outside the villageof Chiusaforte.

Technically, “Ponte di Muro” canbe classified as a five-span viaductbridge. The central, metallic span isrectilinear with a net opening of 69.2

Figure 5. Profile of therail line by the bridge“Ponte di Muro” (docu-mentation dated 1940,Ferrovie dello Statoarchive). The drawingshows a 1,65%, gradientfor this segment of theline, a tunnel at eitherside of the bridge and acontinuous successionof bends.



99

m and a distance of 71.4 m2.betweenthe abutments. The side spans, twofor each side, are planimetricallycurvilinear and made of brick, witharched spans of 18 m each3.

The central span features an un-der-deck truss. In its final configura-tion, it was constructed by coupling,using cross-girders lying at a dis-tance of 297 cm, two truss panelswith a lower curvilinear profile, at adistance between them of 4.5 m.Under the rails and parallel to them,there are rail bearers lying at a dis-tance of 1.75 m between them andinterrupted at the intersection withevery cross-girder.

The structure was built in approx-

imately 1878-1879. However whenthe first train ran on the line on 12 Ju-ly 1879, the bridge was far from beingcomplete! An agreement between theItalian and Austrian governments hadin fact anticipated the date of theopening of the line, but as the centralmetal structure was not yet available,a complex wooden structure washastily erected, to be later removed(with an obligation not to disrupttrain services) once the final structurewas finally in place.

The wooden structure was testedonly at the beginning of July 1879,immediately before the official inau-guration. This is how the news wasreported by Marinelli (1894).

Figure 6. Top, the structure prior to conversion in 2007. Bottom, an original drawing of theelevation of the metal span, constructed in 1933 when the line was electrified and structurallyreinforced (Ferrovie dello Stato archive). The drawing shows an increase in the total sectionof the span, with a subsequent improvement in its structural resistance capacity, at the mid-point of the bridge. The change was necessary because of the increased train load and wasobtained by designing a truss box with arched lower longitudinal beams.


A . C o c c o l o

100

“... Behind the construction of this bridgelies a story that is truly a credit to Italianengineering. Owing to a special arrange-ment between the Austrian and Italiangovernments, it was resolved that the lineshould be open for traffic before the datepreviously assigned to the General Con-tractor and consequently to the sub-con-tractors. With a little good will, workalong the line was completed accordingto the new more stringent timelines, butthe afore-mentioned bridge, whose con-struction had always been considered oneof the most difficult problems ever en-countered in railway history, was still un-finished, on account of the ruggedness ofthe terrain, of the height over the riverbed, of the length of the central span, ofthe very inconvenient access (the bridgeis adjoined by a tunnel at either side) andalso on account of the gradient which is,at that particular point, not lower than 16per 1000. In order to meet the new dead-line, in the impossibility to have the metalspan ready by that date, the Contractoradopted the expedient of building a tem-

porary wooden bridge, which was erectedin two months at an expense of 61,000 lireand which proved to be stable enough forthe line to be opened for traffic on 25 Ju-ly 1879. Meanwhile work continued onthe permanent metal structure, which wasassembled in the maze of wooden beamsthat supported and formed the temporarybridge, and all the while at a height of 40metres above the river bed, almost sus-pended over the heads of the workers, thetrains were providing a regular service, al-beit at a justifiably low speed. Moreover,work had to be carried out in such a waythat service should not be interruptedeven while the metallic span was finallyput in place. And in actual fact the resultwas achieved, without damages or suspen-sion of service… The total cost of thisbeautiful structure (not including the ex-pense of the temporary bridge) rose to545,755 Italian lire, of which 125,755 forthe metallic part.”

More than fifty years later in 1934-34, when the line was modernized

Figure 7. The construction of a temporary wooden structure in June 1879 (AA.VV. 2010).



101

and reinforced and the originalmetallic structure was replaced by anew and stronger span which couldwithstand increased train loads, an-other temporary wooden structuretook centre stage at “Ponte di Muro”.Once again the operation was daring-ly carried out. A large scaffoldingtower was built around the bridge;the metallic span that had to be re-placed was positioned on rollers,moved to the side of the track, laid ontop of the scaffolding and dismount-ed. With the same procedure, thenew metallic span was put in place.

The 1920 accident. On 26 March1920 a tragic railway accident tookplace at the “Ponte di Muro” bridgecausing the death of twelve people,all of them Egyptian students whowere travelling to the universities ofVienna and Berlin. The dynamic ofthe accident was impressive to say the

least. Eight goods carriages standingunmanned at Pontebba rail station, afew miles to the north, suddenly be-gan to move and proceeded along themain track of the line at a speed of al-most 90 km per hour in the directionof Udine.

By a tragic coincidence, at thesame time the express train to Viennawas travelling northwards at a an esti-mated speed of 50/60 km per hour,crashing head-on into the runawaytrain as it was crossing the bridge. Atthe time it was considered fortunatethat the collision had taken place onthe last pier of the northern semi-viaduct rather than on the centralspan, which would probably not havewithstood the impact. Another im-portant factor in limiting the numberof casualties was the reduced speed ofthe passenger train, which by a prov-idential decision by the Chiusafortestation master, was drawn by a single

Figure 8. Top, phases of con-struction of the temporarywooden structure (June 1879)(AA.VV. 2010). Bottom, themetallic structure in operation(AA.VV. 2006).


A . C o c c o l o

102

locomotive. A greater traction pro-vided by a second engine would haveprobably caused the train to derail,pushing it off the bridge.

Present situation. Having withstoodthe damages brought upon by badweather, natural disasters and histori-cal mishaps, miraculously ignored by

Figure 9. Cross section ofthe temporary woodenscaffolding erected to re-place the original metallicspan in 1934-35 (Ferroviedello Stato archive). Onthe left the new, pre-as-sembled structure, in themiddle the structure to bereplaced. It was carried tothe side with ropes andhoists until it was safelypositioned on top of thescaffolding on the right,where it was dismounted.

Figure 10. The railway accident in March 1920 (AA.VV. 2006).



103

WWII Allied bombers (who attackedinstead “Ponte Peraria” at Chiusa-forte and nearby Dogna bridge), thebridge has survived until today in aremarkably good state of repair, par-ticularly considering the total lack ofmaintenance since 1995 when the linewas abandoned.

Before conversion work officiallycommenced, numerous preliminaryinspections were carried out. Theevaluation of the state of preservationof the protective paint on the bridge’smetallic structure, carried out inMarch 2010, was particularly impor-tant (Dorigo 2007).

On that occasion, it was assessedthat the orange-coloured mono-com-ponent primer was in a good state ofrepair, with a thickness of around 200micron across the entire structure.Paintwork, including the top coat inthe classic RAL 8028 brown colour,presented an average thickness of 400micron, and was rusted for around 5-10% of the surface. Below the planeof the rails, on the other hand, the topcoat had peeled off for at least 10-15% of the painted surface, exposingthe underlying primer paint.

In general the state of conserva-tion of the structure, as evaluated bythe 2007 survey, was regarded as ac-ceptable, also in consideration of thefact that the bridge had been aban-doned for twelve years, and the areasat risk of oxidation did not appear tobe in need of immediate repair.

It was not considered necessary toassess the mechanical properties ofthe material by a Vickers hardnesstest, because the evaluation of the sta-tic characteristics of the existing

structure could be banally conducted“by comparison” between railway-re-lated and bicycle-related stresses,without having to establish the pre-cise resistance level of the existingmetallic structure.

2. The conversion to cycle use2.1. General outline. After a numberof years when preliminary designswere presented and evaluated and thetransferral of ownership of the linewas finalized, the project of conver-sion of the Pontebbana line into thenew “Alpe-Adria” bicycle trail finallygot underway in 2007 when the finaldesigns and working plans were pro-duced. The project concerned the

Figure 11. Inside of the truss (the deck is ontop). Paintwork on the lower parts of thetruss has extensively peeled off, exposingthe underlying orange-coloured primer(March 2007).


A . C o c c o l o

104

conversion of the entire 4th sectionand of part of the 5th section (fromResiutta to Dogna) of the line, proba-bly the most complex and fascinatingsegment of the railway.

Right at the start of the planningstage, one of the most important de-sign issues that were considered re-garded the characteristics of the newdecking that would replace the exist-ing rail tracks on the metallic bridges,which were a precious historical fea-ture that it was necessary to preserve.

The approach that was adoptedaimed at finding solutions that wereboth respectful of the existing struc-tures and as unobtrusive as possible,using features that were remindful ofthe original architecture (woodensleepers, simple guardrails with threehorizontal rails) and also very easy toremove, in order to facilitate futuremaintenance. For this reason weavoided solutions that required inva-

sive techniques such as soldiering orbolting onto the original metal struc-tures, preferring to use completelydismountable girder clamps.

The new decking for pedestrianand bicycle use was constructed byremoving the existing wooden sleep-ers and the inspection walkwaysmade of chequered sheets, thus ex-posing the underlying metallic struc-ture (cross-girders and rail bearers).Three HEA180 longitudinal steelgirders were then laid at a distance of132.5 cm from each other, fixed tothe original metallic structure bygirder clamps. For ease of transportand mounting, the girders had alength of only two spans (i.e. con-necting three cross-girders). Theselongitudinal members provided con-tinuous support to glulam larch-wood beams lying on top of them,having a standard 20x24 cm sectionand being laid at a distance of 50 cm,which support the new deck. This hasbeen constructed with panels ofstructural metal grating (with 33x11mm openings), which is less slipperythan the traditional wooden boards,particularly when it rains. The deckwas lined at both sides with metallicrailings, higher than the usual pedes-trian guardrails, made of metal postsand guards and furnished with wood-en hand rails.

2.2. Structural analysis. Structuralanalysis was performed by limit stateverification using a partial safety fac-tor design method. It is not impor-tant, however, to illustrate the analy-sis in detail as it makes reference tothe application of the usual Building

Figure 12. Girder clamps used to fix thenew decking onto the existing load-bearingstructure.



105

codes and is of little scientific inter-est. Only some general information isgiven here, remembering that renova-tion was not aimed at the improve-ment or seismic reinforcement of theexisting structure, which has notbeen modified in its static character-istics or subjected to an increase inloads following its conversion.

With regard to the probabilisticloads which have been estimated onthe new decking, they consisted in auniformly distributed pressure acrossthe width of the structure having a val-ue higher than 5 kPa. However weconsidered the possibility that the newdecking should support the transit of a3-axle service/emergency vehicle (am-bulance, van) with a maximum weightat full load not higher than 250 kN(180 kN in total by the two rear axles).

The structural analysis of the newstructure has been performed usingsimple static schemes, assuming thatit was connected to the underlyingsteel girders through hinge con-straints, created by the girder clampslinking cross-girders and longitudinalbeams. The constraining reactionswere later used in a simplified analy-sis of the underlying load-bearingstructure, formed by the under-railframe made of cross-girders and railbearers.

In particular, the stress derivedfrom the weight of cycle traffic hasbeen compared with that obtained byloading a structurally significant por-tion of the under-rail frame by therailway loads prescribed by theguidelines no. 2711 of 1925 (Ferroviedello Stato 1925), which are lower

Figure 13. Typical cross section of the new decking, showing the wooden cross-beams beingsupported on three points.

Mai

n gi

rder

Mai

n gi

rder

Cross-girder

Rail bearer Rail bearer

Exi

stin

g ra

iling

Longit. beam

New

rai

ling

New

rai

ling

Exi

stin

g ra

iling

Cross-beam


A . C o c c o l o

106

Figure 14. Envelope of the diagram of the bending moments generated in the central beamof the new decking (longitudinal view, two-span beam). The fragmented aspect of the polyg-onal chain is due to the discrete loads applied by the glulam wood cross-beams. The con-straints represented in the figure are materially caused by the cross-girders of the bridgetruss.

Figure 15. Loading diagrams contained in historical documentation published by Ferroviedello Stato, with indication of the load applied by each axle. Top, the two locomotives whichwere presumed by guidelines no. 2711 of 1925. Bottom, the higher loads presumed by guide-lines no. 2715 of 1945.



107

than those of the successive guide-lines no. 2715 of 1945 (Ferrovie delloStato 1945) and therefore implicitlydefining the minimum resistance ca-pacity of the structure, to be com-pared with the new loads caused bycycle traffic.

Despite having a predictable result,this verification was necessary for bu-reaucratic reasons, since the rail-to-trail conversion formally involved achange in the use of the structure.

2.3. The construction stage. The re-de-sign of the bridge truss with the re-moval of rails and sleepers and the con-struction of a new decking took placein Winter 2007-2008, while the conver-sion of the rest of the line was com-pleted in 2010. In this case, the railtracks were removed and the groundwas covered in asphalt concrete, whichwas also laid on the four side spans ofthe “Ponte di Muro” bridge.

The decision of using simple andindependent structural elements andeasily assembling them with bolts andclamps has proved to be a very con-

venient one, cutting constructiontime and limiting safety hazards (par-ticularly considering that the buildingsite was 40 metres above the ground).Regarding this, the choice of main-taining the original railings has per-mitted the instalment of two lifelineropes to which workers were contin-uously harnessed. This was particu-larly important in the delicate phasewhen sleepers and inspection walk-ways were removed and the newdecking was put in place.

Finally, a curious discovery wasmade during the renovation of thebridge’s southern-most span: an oldmine shaft covered by ballast and hid-den inside the central pier. It has notbeen possible to date the cavity,which may have been dug at the sametime as the rest of the structure, or ex-cavated during WWI or at the sametime as the fortifications emergingfrom the rock at the southern end ofthe bridge. Incidentally, these fortifi-cations are not included in the mili-tary description of the defensive lineknown as Vallo Littorio (Bernasconi

Figure 16. Construction ofthe new decking. Top, re-moval of railway sleepers andinspection walkways. Bottomleft, the new cross-beamsmade of glulam larch-wood.Bottom right, the finisheddecking. As shown by thephotographs, employees woresafety harnesses attached viaa shock absorber to the lifelines at the sides.


A . C o c c o l o

108

& Muran 2009), built by the Italianarmy before its entry into WWII. De-spite these uncertainties, it was decid-ed to preserve a visible sign of thepresence of the shaft by bringing it tothe level of the tarmac and closing itsopening with a simple plate.

3. Conclusions. The article has de-scribed of the process of rail-to-trailconversion of “Ponte di Muro”, aviaduct bridge with a masonry-and-steel structure located near the villageof Dogna (Udine), part of the disused“Pontebbana” railway line. Followingthe conversion of the railway line intothe new “Alpe-Adria” bicycle trail,the old bridge has recovered its for-mer function as a crossing of the Riv-er Fella: a function it had lost in 1995when the old line was replaced by anew two-track, in-trench railway, ef-

fectively blotting out the rugged ter-rain that the bridge had masterfullyconquered at the end of the 19th century.

In the place of the old rails andsleepers, the bridge’s steel truss struc-ture now accommodates a newpedestrian and cycle deck: light, easi-ly maintained, and above all respect-ful of the environment and of the ex-isting architecture. We hope that thenew lease of life that has been gainedby the bridge and more generally bythe rail line through their conversioninto a bicycle facility could effectivelycontribute to an ecologically-sustain-able re-launch of these border lands,so harshly affected by historicalevents and by complex and some-times not very sensible choices of in-frastructural development andtourism planning.

Figure 17. Left, the twosouthern spans as theywere constructed (AA.VV.2010). Right, the mineshaft discovered inside thecentral pier.

1 Some authors divide the line in four sections,considering the segment between Resiutta andPontebba as a single section. 2 Data obtained from the original Ferrovie delloStato drawings regarding the replacement of the

bridges’ metalwork carried out in 1933. 3 Span lengths were correctly reported byMarinelli (1894). AA.VV. (2006) erroneouslygives a net span of 14 m.



109

Bibliografie

AA.VV. (1996). Transalpina, un binario tra i popoli. Monfalcone: Edizioni della Laguna S.r.l.,371 pp.

AA.VV. (2006): La strada ferrata della Pontebba. Udine: Ed. Senaus, 197 pp.AA.VV. (2007): Dalle Alpi all’Adriatico in ferrovia con la Meridionale (1857) e con la

Transalpina (1906). Monfalcone: Edizioni della Laguna, 275 pp.AA.VV. (2010): Strade ferrate 1858-1879. Le campagne fotografiche dello Studio Lotze.

Venezia: Marsilio Editori, 200 pp.Bernasconi A., Muran G. (2009): Il Testimone di Cemento. Le Fortificazioni del “Vallo Alpino

Littorio” in Cadore, Carnia e Tarvisiano. La Nuova Base Editrice, Udine 493 pp.Bortotto C. (1979): Un secolo di storia della ferrovia Pontebbana. In Rassegna Tecnica del

Friuli-Venezia Giulia, 1-2: 21-28.D’Aronco M. (2008): Ali sull’Alto Friuli. Bombardamenti aerei Alleati. Udine: Aviani &

Aviani Editore, 256 pp.Dorigo P. (2007): Rilievi relativi allo stato di conservazione delle vernici protettive sui manu-

fatti metallici della dismessa ferrovia nel tratto tra Resiutta e Pontebba – Fantini Eco S.r.l..Unpublished Report, proprietà della Comunità Montana del Gemonese, Canal del Fer-ro e Valcanale, marzo 2007, 17 pp.

Ferrovie dello Stato (1925): Circolare L.C.6/60107/2711 del 30.6.1925. Nuovi SovraccarichiPer Il Calcolo Dei Ponti In Ferro.

Ferrovie dello Stato (1945): Circolare L.C.6/2715 del 15.7.1945. Nuovi Sovraccarichi Per IlCalcolo Dei Ponti Metallici.

Marinelli G. (1894): Guida del Canal del Ferro. Udine: Società Alpina Friulana, 326 pp.Petronio P. (1997): Transalpina – La linea di Wochein. Trieste: Edizioni Italo Svevo, 394 pp.Rampati A. (2002): Carlo Ghega il cavaliere delle Alpi. Trieste: Edizioni Italo Svevo, 124 pp.Roselli G. (1979): Il centenario della ferrovia Pontebbana 1879-1979. Udine: Dopolavoro Fer-

roviario, 43 pp.


Documents

The “Ponte di Muro” bridge on a disused railway line at