Bridge near Limyra

36.3488730.2065119.66Koordinaten: 36 ° 20 ' 55.9 "N, 30 ° 12' 23.4 " E

Road Limyra Attaleia

Alakir Çayı

The Roman bridge Limyra ( Turkish Kirk Goz Kemeri ) in today's Southwest Turkey is one of the oldest segmental arch bridges in the world. The 360 m long bridge leads near the ancient city of Lycia in Limyra over the river Alakir Çayı. Your 26 segmental arches are now buried for the most part. You have an arrow ratio from 5.3 to 6.4 to 1, which gives the building a very low profile and only in the late Middle Ages ( for example, when Ponte Vecchio) with 6.5 was reached to 1 again. Despite their outstanding techno-historical importance, the bridge Limyra little is known; the increasing destruction of the building prompted the German Archaeological Institute (DAI ) in the 1970s to date only field investigation.

• 4.1 brick arches
• 4.2 wall shell
• 4.3 patch

Research

News from antiquity are not delivered over the bridge. First descriptions of the structure appear in European travel accounts of the 19th century: Charles Fellows described during a visit in May 1840, the bridge with 25 arches, the same did Spratt and Forbes two years later. An Austrian expedition with the participation of Otto Benndorf 1882 interpreted the structure as part of an ancient road from Limyra the eastern Antalya. Plans or sketches, however, were not then made ​​.

The first and only scientific survey of the bridge was made ​​by Wolfgang Wurster and Joachim Ganzert on two consecutive days in September 1973 and completed in the three years that followed by further site visits. The results were published in 1978 in the Archaeological indicators of DAI, expressly to refer to the increasing threat of the hitherto almost remained intact bridge:

" Recently, citrus plantations were established in this fertile alluvial plain; in the east of the bridge now arise greenhouses for early vegetables. Through the introduction of intensive agriculture in the area, the bridge is very vulnerable. From the still intact bridge covering the Umwohner refer stone material; Bulldozers to tear system of irrigation canals on the bridge body and crush with their own crawler tracks the pavement. "

The engineer O'Connor summarized the 1993 DAI report in its English-language monograph on the Roman bridge together briefly and also emphasized the exceptional nature of the bridge. Further scientific arguments with the bridge Limyra are not known.

Topographic and traffic situation

The Roman bridge crosses the Alakir Çayı 3.2 km east of the ruins of Limyra ( Measuring point: theater) and 3.8 km north of the present coast near the modern road from Turunçova Kumluca; the ancient name of the river is not known. The local topography is determined by the foothills of the mountain range Tocak Dagi, the go over here in the flat alluvial plain of the Gulf of Finike. In this transition region, the bridge was built just above the point where the narrow river valley opens to the wide mouth level and high water prevents the crossing during the rainy season. While the bridge to the east ends in the gravel plain, the western end is probably to protect against floods directly at the rising rock on. The resulting dictated sharp road bends to the south provided a golden opportunity for blocking the road. Nowadays the Alakir Çayı flows only under three arches of the Roman bridge (as of 1978). Upstream of the dam Alakir Baraji was built for irrigation and flood control in modern times.

Unlike other Roman provinces, the ancient road system in Lycia was hardly developed. While the north -south traffic was mainly about the few river valleys, the west-east routes led unlike today mostly on the mountain heights. Here, the way of Limyra over the Alakir Çayı to neighboring Pamphylia after Attaleia likely a special role to be approached as both regions combined to 4th century AD, the province of Lycia et Pamphylia formed. Compared to the main arteries of the empire, the road links in Lycia had with 3-4 m wide, of course considerably more modest dimensions and were probably limited to the pedestrian and animal traffic load. This also fits that the road surface of the bridge Limyra has no ruts; even traces of a balustrade or a parapet could not be detected on the building.

Construction

With a length of 360 m, the bridge is the largest surviving Engineering structures from antiquity in Lycia Limyra. The bridge has 26 uniform segmental arches, which consist of two superimposed radially positioned walled brick layers. At the eastern end of the bridge are located instead of the former 27 segmental arch of two small, semi-circular arches repair later date that were built only with a simple brick layer. The original, shallow approach of the collapsed arch is in the pillars still visible.

In the archaeological exploratory Wurster and Ganzert found the entire structure before until about the fighters spilled points with river deposits; Exposure tests were not undertaken. Only two of the 28 arches were so wide open, that the clear width and the pillar thickness could be measured directly. However, it was possible to determine the axial distances of all piers constructed from the non -buried bow sections.

Segmental arches and pillars

The spans of segmental arches, that is, the distances between the centers of piers, ranging from 11.60 m to 14.97 m ( sheet 2 and 26 - Counting in the West ( orographic right) starting ). There can be four groups of similar size form, with the following average distances:

Why the distances between the axes of the bridge piers differ from each other in groups, is unclear; as an adaptation to the nature of the river bed, they can not explain. The variations could be indicative of a multiple use different falsework during construction of the vaults.

The pillar width was inspired by Wurster and Ganzert identify only one case with 2.10 m ( between sheets 26 and 27). Subtracting this value from 12.75 m wide arc from normal, a clear width of 10.65 m results. Since all segmental arches have a random height of approximately 2 m, is at the bridge of Limyra the ratio of internal diameter to height unusual 5.3 to 1 Such flat taut arcs were unique in the former stone bridge and remained until the re-emergence of segmental arch bridges in Italy in the 14. century unsurpassed. The largest arc of Limyra Bridge spans even a length corresponding to the 6.4 times its height. The boost of the two arcs repair moves, however, with 2.7 to 1 still within the normal range of semi-circular arches.

Bridge height and level

The total height of the bridge was due to their Verschüttungszustandes not be determined, but rather the distance from the fighters to the road surface; it is only 3.25 m.

The bridge level forms a nearly horizontal plane: While the roadway sheets 1 to 20 at a level of 20.05 to 20.55 m above sea level lies, it falls in an easterly direction in the remaining six segmental arches on 19,94 m to 19,66 m slightly. Given the length of the building, the fluctuations of the authors are considered to be minimal. Since there is no evidence of subsequent lowering of the structure, suggesting the construction of the uniform height on a careful leveling and a solid foundation of the piers. In contrast, the longitudinal axis of the bridge from bow to bow differs sometimes significantly from the main direction.

Statics

Remarkably, the thrust line of the net weight is almost identical with the curve of the arch axis. The static study of the segmental arch bridge proves the great strength of the construction:

" According to current classification, the bridge could take the loads of the bridge class 30 according to DIN 1072; that would mean that they could on an arc a 30 -ton truck and carry, in addition to the remaining surface of the sheet 500 kp / m². The bridge was so rated for the ancient traffic with great security. "

Building

The bridge Limyra was constructed in a composite construction of brick, stone blocks and rubble.

Brick arches

The bricks of the segmental arches made ​​of yellow- red clay, the fine crushed brick was added. The rectangular panels have a size of 40 × 50 cm, about 5 cm thick and consistent with the shorter side upright in the bow Association, so that the matched double walled sheets have a total thickness of 80 cm. The binder material in the 4 cm thick joints is hard lime mortar with the addition of coarse crushed brick and fine gravel. The two semi-circular arches were built of bricks slightly smaller, sometimes even the original bricks of the destroyed segment arc were reused. The fighters are smooth stones hewn limestone ashlar with inclined support surface for the arc attachment.

The two-ply arches allow an efficient use of falsework, which could be moved after the completion of the lower layer to the next brick arch opening:

" The separate into two phases brick construction of the two layers of the double brick arch had two advantages. In the first phase, the falsework had to wear only the load of the lower sheet position, could thus be measured weaker. In the second phase, the weight of the upper layer could be already supported by the lower vault location, so the falsework was back for another bridge opening available. "

Wall shell

As far seen the bridge from opening 2 to 21 has a four-layer brick cladding on the followed by a mortared rubble masonry. The wall shell other hand consists of stone blocks between 22 and 26 arc as well as the two bridge ramps. The repaired areas 27a and 27b differ by the smallness of the built in rubble and the disordered incorporated brick recognizable from the bricks and quarry stone cladding in the west and the cuboid shell in the east. The underside of the sheet of port 26 still leaves the projection-like support for the falsework recognize.

The bridge above the interior arches and pillars made ​​up of a composite of rubble and large river pebbles together with lime mortar.

Pavement

Is only 30-40 cm above the apex of the arches, which consists of large and irregular limestone slabs bridge patch that protrudes on both sides 10 cm above the edge of the bridge. The use of small river pebbles as paving can also repair features on the two semicircular arcs seen. The bridges is 3.55 to 3.70 m wide and increases at the bridge ends at 4.30 m.

Dating

The chronology of the bridge Limyra is considerably more difficult by their exceptional character within the Roman building tradition and the lack of comparative studies of Roman bridges. As a starting point Wurster and Ganzert perform the following characteristic design features of the bridge:

• Multi-span system with the same field width and horizontal bridge rail with low inroad to the bridgeheads
• Very flat segmental arches of double, radially layered brick vaults
• Mortar masonry
• Outer shell predominantly rubble stone with brick leading, partly isodomes ashlar masonry
• Especially large-sized stone slab pavement.

In contrast, most of the Roman stone bridges had rectangular panels and rested on wedge stone vaults that have dominated for a long time also the vault in Lycia. In contrast to the massive and towering semicircular arch bridges that were typical of the Roman civil engineering, provides the bridge Limyra with their flat tensioned segmental arches a much lower and more stretched appearance, so that Wurster and Ganzert " tentatively " a late dating of the building about the time Suggest Justinian I ( 6th century ), for which the use of brick - stone dressings is is in the Lycian regional architecture.

On the other hand, this mixing technology already arrived at the nearby Aqueduct of Aspendos in the 3rd century AD to the application and the Romans certainly knew segmental arch bridges such as explain the two building researchers themselves with three examples, would also be an earlier time of origin at the end of the second or possible in the 3rd century. This early date seems more likely from today's perspective, having in the meantime, seven other segmental arch bridges were documented from the Roman period.

The remains of the Roman bridge at Kemer, which also dates from the 3rd century and its construction has some similarities with the bridge of Limyra, and are located in the valley of the Xanthos.