Introduction
An aqueduct, in the direct meaning of this term, is a part of the conduit in the form of a bridge over a ravine, river, or road. From ancient times, ships could also use aqueducts of sufficient width. This construction is similar in structure to a viaduct, with the difference that it is used to carry water instead of organizing a road or railway track. Although most associated with the Romans, aqueducts were invented centuries earlier in the Middle East, where the Babylonians and Egyptians built elaborate irrigation systems. Roman-style aqueducts were in use as early as the 7th century BC. The Assyrians built a limestone aqueduct 10 meters high and 300 meters long to carry water across the valley to their capital, Nineveh; the total length of the aqueduct was 80 kilometers. This work focuses on the principles of building aqueducts, the materials utilized in the process, the key uses, and the specifics of the repair.
Purpose and Design Features of Aqueducts
The Romans built numerous aqueducts to carry water to cities and industrial sites. The need for clean drinking water led the ancient Romans to build aqueducts as early as the 4th century BC. The first built aqueduct – Akvia Apia – reached a length of 16 kilometers. In ancient times, almost a third of the entire empire was supplied with clean water. Aqueducts were stretched almost throughout the country and conquered lands. Water was supplied to Rome through 11 aqueducts, which were built over 500 years and had a total length of almost 350 kilometers. However, only 47 kilometers of these were above ground; most were underground (the Eifel aqueduct in Germany is a very well-preserved example of this). The longest Roman aqueduct was built in the 2nd century AD to supply water to Carthage. Today, this place is located on the territory of modern Tunisia, and its length is 141 kilometers. Roman aqueducts were extremely complex structures, and technologically, they were not obsolete even one thousand years after the fall of the Roman Empire. Moreover, they were built with high accuracy, as evidenced by the minimum vertical slopes.
Transporting water using gravity alone has proven to be effective. Sometimes, when crossing surface depressions with a drop of more than 50 meters, pressure water pipelines were created – siphons, although the insides of bridges almost always were utilized for this purpose. Modern hydraulic engineering uses similar techniques to allow sewers and water pipes to cross various depressions. However, the water that came through the Roman aqueducts, unlike today, was a luxury item for a long time. The bulk of the water delivered by aqueducts was intended primarily for public needs. Citizens could only collect water that overflowed over the edges of outdoor pools. At the same time, not everyone obeyed the rules of water use. Cases of unauthorized connection to aqueducts were not uncommon, and such secret diversion of water was considered a state crime and punished severely.
The aqueduct was devoid of any decorative details since its main task was to be useful. However, the construction process was carried out in strict accordance with accurate calculations. The details of the aqueduct were located based on the general laws of symmetry without any deviations. The standard structure of this type consisted of three tiers located one above the other. The lower tier included six arches, and the height of each of them reached 20 meters. There were 11 arches on the middle tier, and 24 more were built above them. It is important to note that these structures were not built by slaves or soldiers. The construction required special theoretical training and knowledge of the laws of physics and architecture, which indicates that qualified employees with engineering experience were involved. As a result, this traditional form of the aqueduct was characteristic of most structures in the Roman Empire.
Construction Materials and Repairs
During the construction, advanced building materials were used at that time, such as waterproof pozzolanic cement-based concrete. Later structures erected after the fall of the Roman Empire included stronger materials in their designs, such as cast iron, and engaged streamlining technologies of steam engine power. This made it possible to build more reliable structures in a faster time. Nonetheless, ancient Roman aqueducts were also noted for their high strength. These structures were built from a concrete base on which stone or brick supports were installed, which served as the basis for pipes. Such structures, as a rule, required only local repairs, for example, fixing pipe breaks. The aqueducts that have survived to this day confirm the reliability of these constructions and their resistance to external influences.
Conclusion
Ancient Roman aqueducts can be considered great constructions, many of which have survived to this day due to the reliability of their erection and the uniqueness of the engineering of that time. The involvement of qualified employees and the use of reliable materials made it possible to build sustainable structures that were in demand for public purposes. The construction process itself was characterized by accurate calculations, and serious repairs, as a rule, were not required in the future, which also speaks of the reliability of aqueducts.