Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Did the Romans invent concrete?
Roman concrete, also called opus caementicium, was a material used in construction during the late Roman Republic until the fading of the Roman Empire. Roman concrete was based on a hydraulic-setting cement. Recently, it has been found that it materially differs in several ways from modern concrete which is based on Portland cement. Roman concrete is durable due to its incorporation of volcanic ash, which prevents cracks from spreading. By the middle of the 1st century, the material was used frequently, often brick-faced, although variations in aggregate allowed different arrangements of materials. Further innovative developments in the material, called the Concrete Revolution, contributed to structurally complicated forms, such as the Pantheon dome, the world's largest and oldest unreinforced concrete dome.[1]
Freyssinet invented the concrete hinges.
Leonhardt introduced guidelines in the 1960s which are still used till the 2010s.
Janßen introduced the application of concrete hinges in tunnel engineering.
Gladwell developed another guideline for narrowing cross sections, which predicts a stiffer behaviour than the Leonhardt/Janßen-model
Marx and Schacht translated Leonhardts guidelines for the first time in the nowadays used semipropablistic safteyconcept.
Schlappal, Kalliauer and coworkes introduced for the first time both limit caces (service-limit-states (SLS) and ultimate-limite-states (ULS)).
Kaufmann, Markić und Bimschas did further studies on concrete hinges.
Rawson pointed out that the piling up of atrocities in accounts of the Roman civil wars should not be discounted too quickly as literary invention: "Sceptical modern historians sometimes suffer from a happy failure of imagination in refusing to envisage the horrors which we all ought to know occur too often in civil war." Such gruesome catalogues are characteristic of Roman historians rather than their Greek models, she noted, and Sallust was the first to provide lists of concrete and "horrific "exempla"."
The Romans developed an intensive and sophisticated agriculture, expanded upon existing iron working technology, created laws providing for individual ownership, advanced stone masonry technology, advanced road-building (exceeded only in the 19th century), military engineering, civil engineering, spinning and weaving and several different machines like the Gallic reaper that helped to increase productivity in many sectors of the Roman economy. Roman engineers were the first to build monumental arches, amphitheatres, aqueducts, public baths, true arch bridges, harbours, reservoirs and dams, vaults and domes on a very large scale across their Empire. Notable Roman inventions include the book (Codex), glass blowing and concrete. Because Rome was located on a volcanic peninsula, with sand which contained suitable crystalline grains, the concrete which the Romans formulated was especially durable. Some of their buildings have lasted 2000 years, to the present day.
What the Romans Did for Us, is a 2000 BBC documentary series "looking at the innovations and inventions brought to Britain by the Romans". The title of the programme is derived from the cult movie "Monty Python's Life of Brian", referencing the famous scene where the People's Front of Judea discuss ""What have the Romans done for us?""
Although concrete had been used on a minor scale in Mesopotamia, Roman architects perfected Roman concrete and used it in buildings where it could stand on its own and support a great deal of weight. The first use of concrete by the Romans was in the town of Cosa sometime after 273 BC. Ancient Roman concrete was a mixture of lime mortar, aggregate, pozzolana, water, and stones, and was stronger than previously-used concretes. The ancient builders placed these ingredients in wooden frames where they hardened and bonded to a facing of stones or (more frequently) bricks. The aggregates used were often much larger than in modern concrete, amounting to rubble.
The pozzolanic reaction is the chemical reaction that occurs in portland cement containing pozzolans. It is the main reaction involved in the Roman concrete invented in Ancient Rome. At the basis of the pozzolanic reaction stands a simple acid-base reaction between calcium hydroxide (as Portlandite) and silicic acid.
A crucial factor in this development, which saw a trend toward monumental architecture, was the invention of Roman concrete ("opus caementicium"), which led to the liberation of shapes from the dictates of the traditional materials of stone and brick.
It was in the area of architecture that Roman art produced its greatest innovations. Because the Roman Empire extended over so great of an area and included so many urbanized areas, Roman engineers developed methods for city building on a grand scale, including the use of concrete. Massive buildings like the Pantheon and the Colosseum could never have been constructed with previous materials and methods. Though concrete had been invented a thousand years earlier in the Near East, the Romans extended its use from fortifications to their most impressive buildings and monuments, capitalizing on the material’s strength and low cost. The concrete core was covered with a plaster, brick, stone, or marble veneer, and decorative polychrome and gold-gilded sculpture was often added to produce a dazzling effect of power and wealth.
Modern structural concrete differs from Roman concrete in two important details. First, its mix consistency is fluid and homogeneous, allowing it to be poured into forms rather than requiring hand-layering together with the placement of aggregate, which, in Roman practice, often consisted of rubble. Second, integral reinforcing steel gives modern concrete assemblies great strength in tension, whereas Roman concrete could depend only upon the strength of the concrete bonding to resist tension.
Roman concrete was normally faced with stone or brick, and interiors might be further decorated by stucco, fresco paintings, or thin slabs of fancy colored marbles. Made up of aggregate and cement, like modern concrete, it differed in that the aggregate pieces were typically far larger than in modern concrete, often amounting to rubble, and as a result it was laid rather than poured.[2] Some Roman concretes were able to be set underwater, which was useful for bridges and other waterside construction.
Varro's book on agriculture describes an aviary with a wooden dome decorated with the eight winds that is compared by analogy to the eight winds depicted on the Tower of the Winds, which was built in Athens at about the same time. This aviary with its wooden dome may represent a fully developed type. Wooden domes in general would have allowed for very wide spans. Their earlier use may have inspired the development and introduction of large stone domes of previously unprecedented size. Complex wooden forms were necessary for dome centering and support during construction, and they seem to have eventually become more efficient and standardized over time.
The mortar and aggregate of Roman concrete was built up in horizontal layers laid by hand against wooden form-work with the thickness of the layers determined by the length of the workday, rather than being poured into a mold as concrete is today. Roman concrete domes were thus built similarly to the earlier corbel domes of the Mediterranean region, although they have different structural characteristics. The aggregate used by the Romans was often rubble, but lightweight aggregate in the upper levels served to reduce stresses. Empty "vases and jugs" could be hidden inside to reduce weight. The dry concrete mixtures used by the Romans were compacted with rams to eliminate voids, and added animal blood acted as a water reducer. Because Roman concrete was weak in tension, it did not provide any structural advantage over the use of brick or stone. But, because it could be constructed with unskilled slave labor, it provided a constructional advantage and facilitated the building of large-scale domes.
Petre's early speciality was his work in mass concrete, at the time a novel building material in New Zealand. Widely used by the ancient Romans the formula for making it was lost and a new one only invented in the 18th century. Three of Petre's earliest projects were all constructed in this material: Judge Chapman's house (today known as "Castlamore"), the clifftop villa nicknamed Cargill's Castle in 1876, and St. Dominic's Priory in 1877. However, according to the whims of his patrons, he did also work with more conventional building materials.
In his article "The Intriguing Slave in Greek Comedy," Philip Harsh gives evidence to show that the clever slave is not an invention of Plautus. While previous critics such as A. W. Gomme believed that the slave was "[a] truly comic character, the devisor of ingenious schemes, the controller of events, the commanding officer of his young master and friends, is a creation of Latin comedy," and that Greek dramatists such as Menander did not use slaves in such a way that Plautus later did, Harsh refutes these beliefs by giving concrete examples of instances where a clever slave appeared in Greek comedy. For instance, in the works of Athenaeus, Alciphron, and Lucian there are deceptions that involve the aid of a slave, and in Menander's "Dis Exapaton" there was an elaborate deception executed by a clever slave that Plautus mirrors in his "Bacchides". Evidence of clever slaves also appears in Menander's "Thalis", "Hypobolimaios", and from the papyrus fragment of his "Perinthia". Harsh acknowledges that Gomme's statement was probably made before the discovery of many of the papyri that we now have. While it was not necessarily a Roman invention, Plautus did develop his own style of depicting the clever slave. With larger, more active roles, more verbal exaggeration and exuberance, the slave was moved by Plautus further into the front of the action. Because of the inversion of order created by a devious or witty slave, this stock character was perfect for achieving a humorous response and the traits of the character worked well for driving the plot forward.
The Romans used concrete extensively from 300 BC to 476 AD, a span of more than seven hundred years. During the Roman Empire, Roman concrete (or "opus caementicium") was made from quicklime, pozzolana and an aggregate of pumice. Its widespread use in many Roman structures, a key event in the history of architecture termed the Roman Architectural Revolution, freed Roman construction from the restrictions of stone and brick materials. It enabled revolutionary new designs in terms of both structural complexity and dimension.
Concrete has been used since ancient times. Regular Roman concrete for example was made from volcanic ash (pozzolana), and hydrated lime. Roman concrete was superior to other concrete recipes (for example, those consisting of only sand and lime) used by other cultures. Besides volcanic ash for making regular Roman concrete, brick dust can also be used. Besides regular Roman concrete, the Romans also invented hydraulic concrete, which they made from volcanic ash and clay.
Some of the earliest examples of concrete slabs were built by Roman engineers. Because concrete is quite strong in resisting compressive loads, but has relatively poor tensile or torsional strength, these early structures consisted of arches, vaults and domes. The most notable concrete structure from this period is the Pantheon in Rome. To mould this structure, temporary scaffolding and formwork or falsework was built in the future shape of the structure. These building techniques were not isolated to pouring concrete, but were and are widely used in masonry. Because of the complexity and the limited production capacity of the building material, concrete’s rise as a favored building material did not occur until the invention of Portland cement (and developments by the Edison Portland Cement Company) and reinforced concrete.
Roman art is sometimes viewed as derived from Greek precedents, but also has its own distinguishing features. Roman sculpture is often less idealized than the Greek precedents, being very realistic. Roman architecture often used concrete, and features such as the round arch and dome were invented.
The long-term durability of Roman concrete structures has been found to be due to its use of pyroclastic (volcanic) rock and ash, whereby crystallization of strätlingite and the coalescence of calcium–aluminum-silicate–hydrate cementing binder helped give the concrete a greater degree of fracture resistance even in seismically active environments. Roman concrete is significantly more resistant to erosion by seawater than modern concrete; it used pyroclastic materials which react with seawater to form Al-tobermorite crystals over time.
The widespread use of concrete in many Roman structures ensured that many survive to the present day. The Baths of Caracalla in Rome are just one example. Many Roman aqueducts and bridges, such as the magnificent Pont du Gard in southern France, have masonry cladding on a concrete core, as does the dome of the Pantheon.
Famous concrete structures include the Hoover Dam, the Panama Canal and the Roman Pantheon. The earliest large-scale users of concrete technology were the ancient Romans, and concrete was widely used in the Roman Empire. The Colosseum in Rome was built largely of concrete, and the concrete dome of the Pantheon is the world's largest unreinforced concrete dome. Today, large concrete structures (for example, dams and multi-story car parks) are usually made with reinforced concrete.
A crucial factor in this development that saw a trend to monumental architecture was the invention of Roman concrete (also called opus caementicium), which led to the liberation of the shape from the dictate of the traditional materials of stone and brick. 
Zucchabar belonged to the Roman province of Mauretania Caesariensis. (The film "Gladiator" invented a Roman province of Zucchabar, which did not in fact exist.)
Until the twentieth century, the materials used for building were limited to brick, stone, timber and steel to form structures, slate and tiles for roof coverings, lead and sometimes copper for waterproofing details and decorative roofing effects. The Romans used concrete, but it was virtually unknown as a building material until the invention of reinforced concrete in 1849. Modern construction is much more complex, with walls, floors and roofs all built up from many elements to include structure, insulation and waterproofing often as separate layers or elements.
Translucent concrete has been first mentioned in a 1935 Canadian patent. But since the development of optical glass fibers and polymer based optical fibers the rate of inventions and developments in this field has drastically increased. There have also been inventions that apply this concept to more technical applications like fissure detection. In the early 1990s forms like translucent concrete products popular today with fine & layered patterns were developed.
Roman engineers build monumental arches, amphitheatres, aqueducts, public baths, true arch bridges, harbours, dams, vaults and domes on a very large scale across their Empire. Notable Roman inventions include the book (Codex), glass blowing and concrete. Because Rome was located on a volcanic peninsula, with sand which contained suitable crystalline grains, the concrete which the Romans formulated was especially durable. Some of their buildings have lasted 2000 years, to the present day. Roman society had also carried over the design of a door lock with tumblers and springs from Greece. Like many other aspects of innovation and culture that were carried on from Greece to Rome, the lines between where each one originated from have become skewed over time. These mechanisms were highly sophisticated and intricate for the era.