The architects of Ukhaidir first introduced a new elaborate technique based on the construction of elliptical (pointed) barrel vaults with bricks in similar technique to building a wall and therefore considerably eased the way vaults were built.
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Muslim Architecture under The Abbassid Patronage (750-892AD) by Rabah Saoud
Among the palaces built by Abbassid Caliphs and Emirs that attracted wide interest is the Ukhaidir Palace - Iraq, a fortified living complex containing halls, courtyards, living apartments and a mosque.
The palace, built between 774-775 by Isa ibn Musa(endnote 10) some 75 miles Southwest of Baghdad, was a masterpiece of architectural innovation, which had long lasting impact on the development of architecture. The architects and masons of Ukhaidir first introduced a new elaborate technique based on the construction of elliptical (pointed) barrel vaults with bricks in similar technique to building a wall and therefore considerably eased the way vaults were built. The old tradition consisted of the use of a mixture of mortar and small stones and debris laid out on wooden base. Such method required a lot of wood not available in this arid region and building took considerable time to finish as masons had to wait for the vault to dry to move the scaffolding to another part of the building. This new technique, likely to have been introduced through Persian and Mesopotamian Muslims, provided adequate solutions to these issues.
Further elaboration of the vault construction technique was made in the palace's mosque, through the use of flattened arches to support the brick vault, a technique which became later known as ribbed vaulting (Jairazbhoy, 1972). According to Marcais (1954) this method was also employed in Medinat Al-Zahra (10th century) in Andalusia. This achievement provided the foundations for the rise of Gothic architecture in Europe.
The other innovation was the first use of pointed arches seen later in Al-Aqsa and other Abbassid buildings as indicated above. The other original element introduced in Ukhaidir was decorative consisting of the use of blind arcading which appeared in the Northern façade of the Court of Honour. Again, this feature became an essential element in Muslim architectural decoration and later transmitted to Europe. Here, one has to point to the attitude of Western scholars which connect the use of blind arcading, as well as the origin of ribbed vaulting and a number of other features, to Lambard architects who are considered (by them) to be the main builders of Dark ages Europe, especially in the 10th and 11th centuries (see for example Porter, 1909).
The appearance of this feature in Ukhaidir some 300 years earlier clearly denies such claims. Furthermore, for the majority of these scholars Lombardic architecture seems to provide the answer to the origin of medieval revival of Western architecture. I found a strong similarity between Lombardic buildings, especially around Italy, and Muslim buildings in both structural and decorative terms. A proper investigation, by Muslim scholars, in this subject is therefore urgently needed.
Another innovation in Ukhaidir was the introduction of the first fluted dome which appeared at the crossing beyond the main entrance and which later was adopted in Quairawan mosque.
Finally, Ukhaidir elaborated the defensive technique found in Raqqa by introducing what's known as chemin de ronde along the ramparts. The introduction of arrow slits in its walls enabled defence against attackers. Meanwhile, the four gates, consisting each of a chamber with an inner wall and an outer portcullis which could be lowered in case of assault trapping the attackers inside, provided another defensive architectural technique, again transmitted to Europe through the crusaders.
|Ukhaidir Palace (720-800) showing the pointed
arch and barrel vault of the Great Hall.
Source: Hattstein and Delius (2000), p. 100.