Trezzo_sull'Adda_Bridge
Trezzo sull'Adda Bridge
Medieval bridge in Lombardy, Italy
The Trezzo sull'Adda Bridge or Trezzo Bridge was a medieval bridge at Trezzo sull'Adda in Lombardy, Italy, spanning the Adda river. Completed in 1377, the single-arch bridge held the record for the largest span for over four hundred years, until the beginnings of the Industrial Age,[2][3][4][5] while it was not until the early 20th century that masonry bridges with larger openings were constructed.[6]
Trezzo Bridge | |
|---|---|
Reconstructive drawing (surviving parts in dark grey)[1] | |
| Coordinates | 45°36′42″N 9°31′20″E |
| Carries | Two overlapped lanes for pedestrian, horses, carts, and wagons |
| Crosses | Adda River |
| Locale | Trezzo sull'Adda, Capriate San Gervasio |
| Characteristics | |
| Design | Arch bridge |
| Material | Sandstone |
| Total length | 72.25 metres (237.0 ft) |
| Width | 9 metres (30 ft) |
| Height | 20.7 metres (68 ft) intrados |
| Longest span | 72.25 metres (237.0 ft) |
| History | |
| Designer | unknown |
| Constructed by | Bernabò Visconti |
| Opened | 1377 |
| Closed | 1416 |
| Location | |
The Trezzo Bridge was built between 1370 and 1377 by order of the lord of Milan Bernabò Visconti.[2] Fortified with towers, it provided access to the Visconti Castle high above the Adda.[2] During a siege in 1416, the condottiero Carmagnola deliberately caused the structure to collapse by weakening one of its abutments.[2] Its single arch featured a span of 72 metres (236 ft),[2][3][4][7] according to other sources even as much as 76 m (249 ft).[8] By comparison, the second largest pre-industrial bridge vault, the French Pont de Vieille-Brioude, spans 45 m (148 ft).[2] The rise of the segmental arch was ca. 21 m (69 ft), with a span-to-rise ratio of 3.3:1.[2] The arch rip, measured at the springing, was 2.25 m (7.4 ft) thick,[2] corresponding to a favourable ratio of rib thickness to clear span of only 1/32. The sandstone bridge was almost 9 m (30 ft) wide.[2] Today, the two abutments with overhanging remnants of the arch vault are all that remain.[2]
The Trezzo Bridge was not matched until the metal Wearmouth Bridge of the same span was built at Sunderland, England, in 1796.[9] Longer masonry arch spans were not achieved until the 1903 Adolphe Bridge in Luxembourg.[6]
- Pont de Vieille-Brioude (54 m span)
- Pont Grand (Tournon-sur-Rhône) (49.2 m span)
- Castelvecchio Bridge (48.7 m span)
- Pont du Diable (Céret) (45.45 m span)
- Nyons Bridge (40.53 m span)
- Puente de San Martín (Toledo) (40 m span)
- Ponte della Maddalena (37.8 m span)
- Pont del Diable (37.3 m span)
- Dyavolski most (13 m span)
- Crivelli (1886), table 1.
- Straub (1992), pp. 79f.
- Hill (1984), p. 72.
- Garrison (1999), p. 123.
- Fernández Troyano (2003), p. 93.
- Lay (1992), p. 268.
- Fernández Troyano (2003), p. 116.
- O'Connor (1993), p. 188.
- Fernández Troyano (2003), p. 49.
- Crivelli, Ariberto (1886). Gli avanzi del castello di Trezzo – L'antico ed il nuovo ponte sull'Adda (in Italian). Milan: Prem. Tipo-Litografia degli Ingegneri.
- Fernández Troyano, Leonardo (2003). Bridge Engineering. A Global Perspective. London: Thomas Telford Publishing.
- Garrison, Ervan G. (1999). A History of Engineering and Technology. CRC Press. ISBN 978-0-8493-9810-0.
- Hill, Donald (1984). A History of Engineering in Classical and Medieval Times. Routledge. ISBN 978-0-415-15291-4.
- Lay, Maxwell Gordon (1992). Ways of the World: A History of the World's Roads and of the Vehicles That Used Them. New Brunswick, New Jersey: Rutgers University Press. ISBN 978-0-8135-2691-1.
- O'Connor, Colin (1993). Roman Bridges. Cambridge University Press. ISBN 9780521393263.
- Straub, Hans (1992). Die Geschichte der Bauingenieurkunst. Ein Überblick von der Antike bis in die Neuzeit (in German). Birkhäuser Verlag. ISBN 978-3-7643-2441-4.