Argazali-Puntamena Bridge

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La Ponta d'Argazali-Puntamena
Argazali-Puntamena Bridge
ArgazaliPuntamenaBridge4.jpg

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Location within Pacitalia

Location Stratto d'Argazali, between the cities of Argazali and Puntamena, Palatinia/Sephalusia provinces, Pacitalia
Completed/opened Fall of 2003
Total cost Đ131.1 million
Architects PontaSpan SpA
Construction Specio Marinofizio SpA
Operating authorities Provinces of Palatinia and Sephalusia
Bridge type Cable-stayed
Traffic level 83,217.6 vehicles per hour (9/2005)
Maximum load 479,400 metric tonnes
Span length 2,478m
Bridge zone * 8,316m
Tolled No
* Ministry of Transportation terminology

La Ponta d'Argazali-Puntamena (English: Argazali-Puntamena Bridge) is a cable-stayed bridge connecting the two Pacitalian island cities of Argazali, in Sephalusia, and Puntamena in Palatinia. Although only 560,000 people live within 20km of the bridge's transpogrid radius, the bridge serves as an important road link for the three island provinces of Pacitalia, as well as helping connect the residents of Pacitalia's islands with the mainland.

Planning, construction and bridge opening

The Federal Central Government of the Democratic Capitalist Republic of Pacitalia contacted high-tech and world-renowned bridge architect group PontaSpan SpA in late 1992 with the opportunity of drafting preliminary designs for a bridge between downtown Argazali and Grassofanto, a suburb to the east of Puntamena. After many serious public consultations, the inclusion of natural forces into any possible bridge and government directives as to the location, size and traffic volume of the artery, PontaSpan released their preliminary designs in early 1995. After several tweaks to the size and materials used, the designs were made final in July 1999, and construction began on 1 April 2000.

The bridge, officially opened on 21 November 2003, the day of Pacitalia's five-hundredth birthday celebrations, took three years, five months and twenty days to construct, at a total operating and raw materials cost of 131.1 million douros (real). Prime Minister Timothy Ell and the Premeratimu of Palatinia and Sephalusia were the officials on hand to open the bridge, which was, after minor controversies before construction, remarkably completed on schedule and opened on the intended date.

Pre-construction controversy

The only controversy that occurred during the planning and construction of the bridge was the selection of a contractor to build the structure. Originally, Puntafora's PazaloCerma SpA had been selected to fulfil the duty, but they pulled out on 19 January 2000, citing 'fixable legal issues and financial troubles'. That left the government and PontaSpan only two months to find a replacement, and luckily for them, they did, as PazaloCerma's main rival in Amalfia province, Specio Marinofizio SpA, stepped up to the plate and took advantage of the negative publicity directed at PazaloCerma by signing the lucrative construction contract.

Composition and technical design

The bridge is made of a high-density concrete and wrought-iron/titanium composite material called Ferrotex. Ferrotex is able to withstand major structural damage caused by natural phenomena like hurricanes and earthquakes.

Due to the peculiar conditions of the Stratto d'Argazali, several unique engineering solutions had to be found. The water depth reaches 65 m, the seabed is mostly of loose sediment, the seismic activity is significant, and the stratto is expanding at a rate of about 27.3 mm a year, thus the possibility of tectonic movements had to be taken into account. Special construction techniques were applied. The piers are not buried into the seabed, but rather rest on a bed of gravel, which was meticulously levelled to an even surface (a difficult endeavour at this depth). During an earthquake, the piers should be allowed to move laterally on the seabed; the gravel bed absorbing the energy. The bridge parts are connected to the pylons using jacks and dampers to absorb movement; too rigid a connection would fail in the event of an earthquake, but the bridge should not have too much lateral leeway either, so as not to damage the piers. There is provision for the gradual expansion of the strait over the bridge's lifetime.

Transport specifications

Under Pacitalian Ministry of Transportation guidelines, the bridge has a minimum of six lanes (three northbound and three southbound) open at all times of the calendar year. However, the bridge has all ten lanes (five and five) open during most of the year. The bridge carries the merged traffic of the A60 and B919 freeways across the stratto. From south to north (the principal direction of traffic), the bridge traffic follows this pattern of general movement (weather and road conditions permitting):

  • Bridge Zone begins 1.5km south of the bridge's southern ramp/terminus.
  • B919 traffic merges onto the A60 about 1.2km south of the bridge span
  • Merge adds one lane southbound and one lane northbound (total of ten lanes, five each way)
  • Bridge's southern ramp begins 605m south of the south shore of the strait
  • Bridge reaches two-thirds full traffic height above water 210m out from south shore
  • Bridge reaches full traffic height above water at centre of span
  • Bridge lowers to one-third full traffic height above water 160m out from north shore
  • Bridge's northern ramp ends 558m north of the north shore of the strait
  • Route curves northwest from Grassofanto into downtown Puntamena; B919 traffic merges off northeast (Y-fork)
  • Bridge Zone ends at A5 interchange, 4.6km from bridge's northern terminus.

Speeds, traffic volume and other technical specifications

The posted speed in the fast lanes of the bridge (the three inside lanes NB/SB) is 100 km/h. The posted speed in the slow/exit lanes of the bridge (the two outside lanes NB/SB) is 90 km/h. All exits have posted speeds of 70 km/h, and the Y-fork should be driven at a speed of 80 in the fast lanes and 70 in the slow lanes, according to a Ministry of Transportation release. Vehicles not able to exceed 60 km/h should not use the bridge, and bicyclists and rollerbladers should use the provided sidewalks (shared with pedestrians).

The bridge handles an average of 83,220 vehicles per hour, with a peak of 152,245 at around 4.30pm local time and a statistical valley of 11,559 at 3.15am local time. The busiest months on the bridge are February through November.

The bridge's maximum load is 479,400 metric tonnes simultaneously. Thanks to the arched shape of the bridge and thus an increased tensile strength, a bridge length that would normally only be able to hold around 275,000-300,000 MT can carry more simultaneous weight. The bridge's length is 2,478m, making it one of the world's longest cable-stayed bridges.