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3.8 Preparatory works to reconstruction

Preparatory works to be held at this stage are aimed at preparing the ancient masonry to bear the bridge loads. Main objectives of this category of works are the following:

• to have a cleaned and good masonry layout in the abutment inner portion;
• to have a stair shaped (with steps) contact surface between ancient and new masonry;
• to have any fracture or masonry incoherence repaired by injection;
• to have contact surface prepared for the best mortar grip (following construction materials specifications).

This work stage is extremely important to avoid any unforeseen settling of the bridge, and should be approved by the work Supervisor.

3.8.1 Contact surface between ancient and new masonry

As before specified, contact surface has to be optimised for a perfect connection between ancient and new masonry. All the issues concerning the quantification of the dismantling works of the abutments fill are related to the finding of a perfectly coherent and stable masonry layout and contact surface. It is required to refer to structural design specifications to have detailed notes and warnings about this issue. Anyhow bridge thrusts are supposed to be born by a perfect masonry layout, if this is not found, other structural devices and strengthening should be worked out. Stair shaped contact surface is required in order to have an efficient connection and to avoid any shift, for the same reason non rubble should be present and surface will have to be prepared for the best mortar grip following construction material specifications

3.8.2 Repair of the cracks in the vaults

Any voussoir of the ancient bridge, which is still on-site, should be removed unless its mechanical behaviour is proved by investigations to be identical, (or better), to new ones. Integrity limit, (line under which voussoirs are not cracked and in perfect conditions), should be respected and determined on the responsibility of the work Supervisor. In the case that some non-structural damages are found either in the intrados, either in the extrados of the vault, they should be repaired to avoid any water infiltration that may cause further damages.

3.9 Remounting of the remaining portions of the bridge

Remounting of the portions of the bridge which have been dismantled due to structural and safety requirements should be replaced in the original locations if their conservation condition is suitable to the reuse and if the stone elements are not cracked. Any surface damage and deterioration, due to the shootings, may be repaired unless this doesn’t require a stone re-cut or a completely new finishing work which would lead to the loss of the original stone historical value.

Selection of the stones suitable for the re-use is a duty of the work Supervisor depending on direct visual inspection of each stone with the eventual help of investigation devices. Bridge elements over the load bearing arch are not structurally so important, but their integrity is anyhow required to avoid any future deterioration of the ancient areas.

Remounting works depends mostly on the condition of the stones after the dismantling stage and on the rubble that may be still stitched. Stones should be carefully cleaned from any ancient mortar layer without ruining the worked surfaces with slight scraping and scratching. Careful cleaning should be performed also in the slots, purposely built for metal cramps connections, to avoid any reduction of the lead grip. Shape of the slots should be restored with their base slightly larger than the top.

Technological procedures, for remounting and assembling, will follow same specifications given for new stone elements. During disassembling stage, it is suggested to maintain the same numbering and classification system that has been proposed in the design, this way no difficulties and no misnaming will arise during the performing of the remounting stage.

Remounting should be performed by respecting the original locations, either for practical requirements, (otherwise stones will not match with the adjacent ones), either for conceptual and historical requirements which are aimed at maintaining unchanged the stone layout.

3.10 Bridge construction materials

Construction materials, for new bridge elements, haven't been yet completely defined and finalised due to unforeseen delays; this of course make things more difficult for the architectural design and, for sure, a revision will be necessary once this information come to our knowledge. Anyhow, on the architectural side, it is important to use same construction materials as the original ones, or at least the most similar ones still available in nature, unless there is any structural risk, (see §4.6 of this report). LGA Company, in charge for the laboratory tests, will define construction materials depending on the technical approvals and on requirements coming from structural design. General Engineering is not involved in the determination of the construction materials and therefore may be not considered responsible of anything concerning the matter. Nevertheless a brief updated summary is here next reported for completeness sake, (refer also to §2.3.6 of this report):

stones:

Type and origin of stones that will be used are equal to the ones of the former bridge:

• Tenelija stone, (oolithic limestone rock), will be used for the construction of the bridge, quarried from the same place from which it was presumably quarried the original one. Specifications about type, quality, requisites and warnings are given by stone experts, (refer also to chapter seven of this report).
• Krecnjak stone, (limestone hard and resistive marble-like), will be used for the bridge pavement and for the stone slabs covering the inner lightening voids. Specifications about type, quality, requisites and warnings are given by stone experts.

mortars:

It seems most likely that different types of mortars will be used for the load bearing arch, for bridge elements and for pavement. Moreover it seems that an historical mortar may not be used due to structural and safety requirements. Joint thickness have not been yet defined.

bridge fill and terra rossa:

Most likely, as much similar as possible to the ancient ones. Still to be approved.

stiffening rib masonry:

Will be built in a good, coherent and stronger layout than the one of the ancient bridge, following structural design requirements.

metal elements:

It seems most likely that metal elements, which are not visible due to their inner location, will be of stainless steel, while a little number of them and the fence, that are visible, will be in forged iron as the ancient ones. GE and LGA have noted that a full historical approach could be followed, but ICE has decided not to take any risk about the matter, using stainless steel. It is required by GE that, at least, these elements could be burnish coloured and not shining to avoid any shocking impact during the public visits to the yard.

lead:

Most likely a current available lead with similar characteristics to the ancient one, the chemical composition of which includes several elements in very small percentages.

3.11 Reconstruction of destroyed parts

When all the above design steps have been correctly performed, and any unforeseen issue has been faced, reconstruction works of destroyed portions may start. The proceeding of the works, and the different phases, have been described in chapter six of this report: phases should be followed in order to assemble all the stone elements at the proper time. If any unforeseen difficulty is found, design phases may need to be changed in agreement with General Engineering.

Stones, that will be used for the bridge, should match all the requirements given by the stone experts and the proper time for drying should have been elapsed from the moment of quarrying. Construction material specifications, given by LGA Company, will have to be followed.

During the reconstruction stage, the centering shouldn’t be loaded with any unforeseen types of dead or live load, and what is even more important, shouldn’t be loaded asymmetrically: for the above reason it is required that two teams of workers will proceed from both sides of the bridge, assembling voussoirs and, (subsequently), all the other bridge elements.

Reconstruction work of the bridge will be one of the most undertaking moment of the rehabilitation project, either because it is required to respect a very tight timetable, either because many different design specifications will have to be detailed followed: at the same time it is necessary to check and verify many parameters, data and design drawings as here next summarised:

In other words, reconstruction of the bridge requires, first of all, that the design work is absolutely clear and well known to work Supervisor, to the yard Director, and to the workers. Nowadays this peculiar construction technique is not anymore performed and no one will be confident with it, unless some tests and attempts are tried off-site: workers should be well aware of the methodology and, what is more important, of the technique of lead pouring with related healthy risks.

Here, in next paragraphs, main requirements about the whole process will be given, examining every single element to be mounted or assembled, and giving notes about the global structure; but for a better understanding of the assembling disposition of the different stone and metal elements, refer to chapter 9 of this report.

Bridge main structural and architectural elements have been described in chapter two of this report and represented in RE drawings; a good knowledge of the bridge characteristics and technology is required for an easy comprehension of following paragraphs.

3.11.1 Lead pouring main requirements

Before proceeding to assembling works, it has to be pointed out that stones, (following ancient technique), should be connected with mortar and with additional metal strengthening devices that are anchored to stones by melted lead poured in purposely built slots (gaps). For the above reason special expertise and devices for managing the lead are required and the following matters should be underlined:

• Lead is strongly toxic: for melting and pouring works, adequate safety precautions are necessary (LGA note).
• It will be necessary to pour lead either off-site, either on-site (over the vault): special care should be put therefore to avoid any danger for the workers and accidents on the yard. The risk of fire, that may be caused during lead melting, should be strongly limited by protecting the wooden deck.
• Lead should be perfectly melted before it is poured directly into stone channels with no waiting and no different route, this to avoid premature solidification.
• Exact composition of lead to be used will be given by LGA.
• No water (not even hot water) should be preliminary poured in stone channels or slots to avoid vapour explosion when lead is poured: stone should be perfectly dry (LGA note).
• No thermal shock is suffered by the Tenelija stone due to lead pouring (LGA note).
• Stone channels and slots should be accurately cleaned from stone powder before lead is poured (LGA note).
• Dowels should be heated to avoid premature solidification of lead (LGA note).
• Prior the pour any trace of dirty or slag should be removed from the surface of the liquid lead (LGA note).
• In the fine grained porous oolithic surface of Tenelija the lead flows on a film of air on the stone surface pores: polishing of the channels is not necessary to encourage flow but it can be of help in problematic areas like low gradient channels (LGA note).
• Mortar layer in the stone joints should not interfere with channels for lead pouring, and should not obstruct them.
• In BoQ lead is not quantified and it should be considered included in the supply of assembled stone blocks.
• Lead cover around metal elements should be at least mm 5 (to be confirmed by LGA).

Important note for stone slot carving: whenever stone blocks are foreseen to be carved with slots, either for placing dowels, either for placing cramps, it has to be carefully verified that these slots are not too close to the outer margins of the stone block, in order that the stone edge is not weakened and no fracture is caused. A practical rule to be followed may be to keep a minimum distance of three times the diameter of the slot (e.g.: if the slot has an average diameter of 6 centimetres, 18 centimetres, at least, should be the distance from its edge to the stone outer edge).

3.11.2 Mortar and stone joints

Joint thickness hasn’t been yet defined and will depend on co-ordination results between laboratory tests and structural design. Architectural design has been worked out considering it equal to zero, (as required by PCU TA), and this will allow additional stone cut tolerance: refer to chapter 7 of current report. Joint thickness dimension depends on the types of the mortars that will be used for the different bridge portions and on related strengths.

For what concern the BoQ mortar should be considered included in the assembling work and in the masonry work.

3.11.3 Vaults (arch voussoirs)

Arch voussoirs after final stone cut, (see chapter 7 of this report), should be prepared with all the foreseen slots and channels before they are assembled. Preparation of the voussoirs should be performed relating rows to the adjacent ones, to avoid any incoherence related to the location of the inner joints in arch rows. Foreseen steps may be performed for the preparation of the voussoirs (refer to chapter 9 of this report for more notes):

• carving of the slots for the dowels on side faces of joints;
• carving of the channels on one of the side faces (upper face);
• placement of the dowel with lead in one of the side face (lower face);
• carving of the slots and of the traces for the cramps on one of the side faces of joints (upper face);
• carving of slots and of the traces for the cramps on the extrados of the voussoir;
• row side joints should match, allowing an uniform thickness mortar layer, (of foreseen dimension);

Following requirements are given:

• slots for dowels should be:
• on lower face, wide enough to insert the dowel and pour the lead;
• on upper face, wider than the others in order to allow stone slight adjusting during assembling;
• slots positioning should be determined accurately in order that the dowels and the slots of adjacent rows match and suit perfectly, being stones in their final position;
• slots should widen slightly, (about 5° lateral faces gradient), towards the bottom of the slot;
• carved slots and channels should be accurately cleaned from stone powder before pouring lead;
• dowels should be inserted in the slots and anchored with lead in an orthogonal position, (related to the stone face); before lead solidification the dowel has to be maintained in correct position;

When all the above has been correctly performed, (presumably in advance and off-site), the arch stones may be assembled on-site as ordinary voussoirs with mortar, but following design positioning and making sure that dowels fit perfectly in the slots of the previous row, (larger slot). Following requirements are given:

• it is suggested to check matching before applying mortar layer over the joint surfaces;
• mortar shouldn’t obstruct channels for lead pouring;
• the position of the dowel in respect of the slot should be checked to avoid obstruction of the channel caused by the dowel itself; (position may be checked by the use of endoscopy devices or any other proposed); (LGA note);
• dowels should be heated before lead pouring;
• lead should be poured following previous paragraphs requirements into the top edge of the channel;
• gradient of channels varies depending on the voussoir position in the load bearing arch; for starting voussoirs there will be very low gradients, but this shouldn’t be a problem, (according to LGA tests), for the correct pouring, nevertheless in those cases a more accurate smoothness of the channel surface is advisable;

As subsequent step, extrados cramps and side cramps, (by the inner row joint), should be placed and anchored with lead. It is important to note what follows:

• pouring of lead inside the slots of the cramps will be sometime an undertaking task due to the progression level of the arch: more difficulties will arise at the springer level for the extrados cramps and at the top level for the side joints; for the above reason, practical devices, to pour lead, may be worked out like cups or funnels;
• load bearing arch extrados may be roughly cut in the central portion, but along outer margins, in a thickness equal to the stone cornices, cut will be more accurately performed to allow cornices superposing, and extrados cramps should have their carved traces in order to suit the curvature of the extrados profile;
• cramps thickness should not interfere with the joint thickness and cramps should be embanked in the stones; the edges should be widen;
• extrados cramps are the only ones in the bridge which share the same slots: where one ends, the other starts, leading to a sort of an interrupted metal ring: five rings are over the extrados; extrados cramps, for the above reason, will have to be cut at different sizes, (depending on rows to be connected), and bent until the U shape is reached;
• side cramps, (located in the inner row joints), may be of similar sizes because they do not depend on the stone length and they simply cross the joints;
• key stone voussoirs will not be linked to the adjacent ones with dowels, and will not have side cramps and channels because it wouldn't be possible to mount them.

Stone voussoirs located at the edges may be cut to take off any redundant portions of stone that comes out from the average elevation plan, while, the finishing work may be postponed and performed also with the aim of adjusting some discontinuities and too high imperfections or steps on the elevations and on the intrados side.

The assembling of the load bearing arch will require special accuracy and a full understanding of the ancient constructive technique; some additional notes are here next provided:

• stone front joints and their gradient should be checked, while works are ongoing, with reference alignments, making sure that no different direction (from design) is taken; this because also slight incoherent deviations of the joints may cause a very disarranged global appearance of the bridge arch;
• when centering will be dismantled, or at the end of the works, a finishing work of the intrados arch is required with the aim of smoothing some projecting stone edge or reducing some small steps among adjacent voussoirs;
• finishing work of the arch requires special care and a supervision by an artistic consultant to determine the right compromise between smoothness and roughness;
• it is strongly suggested that Company, in charge of the rehabilitation works, refers to the 1:1 test sample performed at the beginning of the work;
• it is moreover suggested that Company, in charge of the rehabilitation works, could refer also the ancient bridge recovered stones with accurate observations.

3.11.4 Stiffening rib and fill

Stiffening rib may be considered as the structural spine of the load bearing arch: it is quite an important element for the stability and resistance of the bridge. The rib should be built in a good masonry layout, much more coherent than the one previously built for the former bridge, (following structural design requirements). Construction materials specifications, (stone and mortar), will be given by laboratory tests in co-ordination with structural design.

The rib should be perfectly connected to the load bearing arch, and the grip should be guaranteed by the rough finishing of the extrados profile. The rib should be connected, as well, to the abutment inner masonry, and abutment masonry is supposed to be already resumed with a stair shaped profile, cleaned from any rubble and with a compact and stable layout. Even this connection should be performed with accuracy in order to guarantee structural continuity.

When the arch centering will be released, the connections of the rib will have to be carefully checked and if some cracks have developed due to a slight settling of the structure, they will have to be repaired. Bridge fill, underneath lightening voids, may be an incoherent masonry (stone and mortar): construction materials specifications, (stone and mortar), will be given by lab tests in co-ordination with structural design

3.11.5 Lower cornices

Lower cornices should be superposed to the load bearing arch and should jut out as defined in design drawings. Stone cornices are stone elements of a short straight profile and they should match the slight curvature of the bridge arch extrados: some adjusting will be necessary and are foreseen to be performed on-site to make them fit over the structure.

A careful control of the global layout of the cornices is required because cornices, (both lower and upper cornices), will determine much of the esthetical appearance of the bridge, and their peculiar connection over the key stone with their gradual and mutual jutting out is, architecturally speaking, a very important detail, as well as their ending edge with a gradient cut.

Lower cornices should be connected with the arch with a mortar layer, while on the top they should be tied with one row of cramps of similar size crossing the joints, (see design drawings). Refer to previous paragraphs for what concern notes about slots, cramps and lead pouring.

First lower cornices next to abutment walls are smoothed with an additional cut following a 45° plan.

Refer to chapter 9 of this report for details about the assembling of these stone elements that should be mounted as they were in the former bridge.

3.11.6 Spandrels

Spandrel walls are made of Tenelija blocks connected with a mortar layer and with cramps on top sides. Cramps are of the type of similar sizes being placed over connection joints. About spandrels the following should be underlined:

• for specifications about stone cut of the spandrel walls refer to chapter seven of this report;
• spandrel walls, as all the other elements, should be assembled proceeding symmetrically from both sides of the abutments;
• spandrel stone blocks have been designed in order that the ones that are next to the abutments should be linked and anchored to the abutments inner masonry;
• connection among spandrel wall blocks and lower cornices is one of the most delicate, since spandrel blocks will have to be cut with a very thin and angled profile that may break easily; therefore block layout may have a slight gradient following design drawings, (and ancient configuration), that can reduce this connection angle;
• not all of the stone blocks will be anchored to the adjacent ones with metal cramps, depending on the stone block size; refer to design drawings;
• by the west side, on the top, the spandrel layout is not anymore horizontally oriented by it follows the bridge slope and it is made of smaller size blocks: this will have to be performed according to design drawings (and to ancient configuration), being a peculiarity of the historical development of the structure;
• spandrel walls, on the back side, (inner side), have a masonry layer which make the profile regular despite the stone blocks are of different thickness dimensions; the above device is supposed to have also a sealing function of the inner voids;
• spandrel walls and stiffening rib will be interposed by the bridge lightening voids which will bring a precious structural advantage to the bridge; during the bridge construction it is important to manage the progression of those different elements to avoid low workability in narrow places;
• refer to previous paragraphs for what concern notes about slots, cramps and lead pouring.

Refer to chapter 9 of this report for details about the assembling of these stone elements that should be mounted as they were in the former bridge.

3.11.7 Lightening voids and krecnjak cover slabs 

As already underlined, the lightening voids bring structural advantage to the structure which is not uselessly loaded. Inside those voids no rain water is supposed to get trough, but in case of any unforeseen infiltration or condense phenomena, on the bottom there should be a compact and waterproofing mortar layer, (construction material specification will be given by laboratory tests), with the function of protection of the load bearing arch. At the lower level of the void a drainage system is foreseen (refer to following paragraphs about drainage and waterproofing: §3.13).

Lightening voids are two per side, divided by the rib and covered by stone slabs of the type of krecnjak stone; these krecnjak stones should be assembled one next to the other very tightly with their joints sealed with mortar in order to avoid infiltration. Krecnjak stones should be placed over the rib on one side, and over the spandrel masonry on the other, (refer to design drawings transversal sections).

3.11.8 Upper cornices

For upper cornices, specifications may be similar to the ones given for lower cornices, with the difference that in this case no problem will arise due to the curvature profile: upper cornice should be anchored to the inclined, (but straight), profile of the spandrels with a mortar layer. Only on the top of the bridge, even the upper cornice, should follow a slightly curve profile directly over the lower cornice: this is a very important architectural detail because spandrel walls should have a slope tangent to the curvature of the lower cornice that joins the curvature itself; this way the upper cornice, at the top, will not have any discontinuities following a sort of a delicate straight profile that slightly bends when meets the lower cornice. At the same time the upper cornice juts out from the spandrel profile, and consequently from the lower cornice, (which is almost on the same level of the spandrel walls: refer to transversal section drawings).

The upper cornice stones will have, on their extrados side, two rows of cramps, of the type of similar sizes, crossing the connection joints, plus one or two slots, (depending on the cases: refer to design drawings). Position of the slots, of course, should be verified with the parapets, and will have to respect either the connection joints among parapets, either the connection joints among cornices. Slots on the upper cornice will be of the larger type, (to be poured on-site), should be widen at the bottom, and should be fed by a short channel with a planar gradient of 45°: channel has to be short because it is supposed to be almost totally covered by the parapets, but at the same time a slight slope towards the slot has to be guaranteed to allow correct pouring of the lead. Refer to previous paragraphs for what concern notes about slots, cramps and lead pouring.

Refer to chapter 9 of this report for details about the assembling of these stone elements that should be mounted as they were in the former bridge.

3.11.9 Parapets

Parapets are more sculptures than worked stones, and it is obviously quite difficult to give specifications for something which should be the result of an artistic work. Parapets are huge monoliths of quite thin profile, their lower edge should be carved with one or more slots (following design drawings), and these slots should be wide enough to host the dowels and should be anchored with melted lead as well as all the dowels of the voussoirs. Refer to previous paragraphs for what concern notes about slots, cramps and lead pouring. For the assembling it should be noted the following:

• slots positioning should be determined accurately in order that the dowels of the parapet and the slots of the cornices match and suit perfectly, being stones in their final position;
• slots should widen slightly (about 5° lateral faces gradient), towards the bottom of the slot;
• carved slots and channels should be accurately cleaned from stone powder before pouring lead;

• dowels should be inserted in the parapet slots and anchored with lead in an orthogonal position, (related to the stone face): before lead solidification the dowel has to be maintained in correct position;
• it is suggested to check matching before applying mortar layer over the joint surfaces;

• parapets will be assembled over the upper cornices of the bridge with a mortar layer that shouldn’t obstruct the channels and the slots for lead pouring;

• the position of the dowel, in respect of the slot, should be checked to avoid obstruction of the channel caused by the dowel itself; (position may be checked by the use of endoscopy devices or any other proposed); (LGA note);
• dowels should be heated before lead pouring;

• lead should be poured following previous paragraphs requirements into the top edge of the channel;

• gradient of channels varies depending on the parapet position in the bridge; there might be very low gradients, but this shouldn’t be a problem, (according to LGA tests), for the correct pouring, nevertheless in those cases a more accurate smoothness of the channel surface is advisable;

parapets should be cut not only as single stones but evaluating also the adjacent ones and have to be considered as a whole: the result have to be a continuos an harmonic shape and lateral joints have to be checked and well connected. On top of the parapets, cramps have to be placed crossing the side joints and following all the above notes given for cramps, slots and lead pouring. These cramps should be embanked in the stone and should be of forged iron as the ancient original ones (being well visible). Iron should be forged accurately by hand work, since it has been found that a good forging prevents from rusting.

Parapets, while proceeding up to the key stone, slightly slant outwards. No quantification of this peculiarity has been possible due to documentation lack. An evaluation of the matter should be performed on site depending on optical effects. Quantification and variation along the parapets length will be decided by the work Supervisor.

Structural design and an on-site test on 1:1 model will define if parapets will have to be additionally strengthened to match currently safety requirements to avoid collapse due to the crowd’s thrust.

Refer to chapter 9 of this report for details about the assembling of these stone elements that should be mounted as they were in the former bridge.

3.11.10 Bridge pavement

Starting from the krecnjak stone slabs, different layers have to fixed before the bridge pavement, as here next listed:

• bridge fill (incoherent masonry layout);
• terra rossa;
• mortar (special waterproofing mortar);
• stone pavement.

Dimensions are given in design drawings and construction materials will be defined by laboratory tests. It is important to stress that, either mortar layer, either "terra rossa", should work as a durable waterproofing layer, and if the above is not guaranteed by the tests, it has absolutely to worked out another waterproofing device that may be also gathered from recent technologies construction materials. Terra rossa surface should be treated with special process that will be defined by laboratory tests.

Pavement is composed by stone rows and stone tiles; layout of them may be worked out from design drawings and not randomly performed, since, as it has been conceived, should help rain water to flow away. Tiles and rows should be assembled carefully on a flat and homogeneous preparation layer making connections as much close as possible and sealing them to avoid rain water infiltration. Pavement will have to be accurately limited by stone parapets and even those joints should be sealed.

Pavement row stones should be bevelled and shaped as the ancient ones in order to make the walk easier to the users.

3.11.11 Fence

Iron fences were most probably added in a subsequent time, but should be considered anyhow as an historical element of the moment and have to be performed as described in design drawings.

Fences layout is very peculiar and has got many vertical bars oriented nor straight nor orthogonal to the pavement and are a typological characteristic of the monument to be repeated. Fences should be made of forged iron, (construction material specification will be gathered by laboratory tests); forging should be accurately performed and hand made to guarantee a protection from rusting and quick deterioration. Fences should be connected to the parapets following the ancient construction technique which foresees the use of lead that may be either poured either used in small hardened pieces to be hammered inside the slots to fix firmly and permanently the fences to the stones. Additional horizontal bars (in three rows) should be assembled trough purposely built rings in the vertical ones. Bracing bars, instead, have a stabilisation function and they make a curvature outwards that ends in a joint in the stone parapets. Fencing sometimes prosecutes over the sills of the abutment’s parapets and ends differently on every side.

Vertical bars were shaped, on top, as an arrow; this has been repeated in design drawings, but it should be evaluated, following the local safety requirements, if this may be repeated to avoid any danger to the end users; anyhow arrows are at an height which is approximately of cm180 from the walking path level, therefore a smoothing of the arrow may be enough to avoid dangers.

Refer to chapter 9 of this report for details about the assembling of these elements that should be mounted as they were in the former bridge.

CREDITS:

Intellectual property of this report and of the design drawings is owned by General Engineering s.r.l.

© - General Engineering Workgroup -

SOURCE:

Final Design Report