Civil Engineering Reference
In-Depth Information
(1) Most gates and major entrance doorways have arched lintels. Generally these
features comprise two or more successive archivolts; and are of burnt brick
even though the general fabric is of mud brick (cf Vol 1, ill 17)
(2) Nothing relating to other arched construction occurs in connection with
temples.
(3) h ere are references to vaults in connection with secular buildings (palaces),
but it would seem relating to subsidiary rooms or passageways, not to principal
apartments (e.g. throne rooms).
(4) h e most prominent representations/references concerning vaulted rooi ng
relate to underground structures—notably tombs (i.e. funerary vaults).
(5) Little direct information is provided concerning details of construction.
Arcuated
brickwork
355
In fact arcuated construction in Ancient Mesopotamian brickwork is a subject
which can not be set out clearly and dei nitively in the limited compass available
here. For an itemised survey of the evidence reference should be made in the i rst
instance to Heinrich's lengthy article
Gewölbe
in the Lexikon der Assyriologie 3,
pp. 323-340. Here individual instances are ordered under the categories of struc-
tural form (arches, barrel vaults, domical vaults); process of construction (corbelled,
“pitched”, radially set); materials of construction (mud brick, burnt brick, gypsum
mortar, lime mortar, bitumen mortar); and, above all, architectural disposition
(utilitarian constructions, underground constructions, free standing buildings).
Heinrich seeks to arrive at an outline statement of arcuated construction form
this itemisation, but in the upshot his statement is very generalising—and may
well rel ect the facts of survival—obviously the rooi ng of underground features
is more likely to survive than the rooi ng of free standing buildings. However his
comments are worth attention.
He states that Mesopotamian brick-layers were able to fashion arches and vaults
by corbelling and by 'pitched brick' construction, and that construction in these
techniques required no temporary support during construction. On the other hand
they could also fashion arches and vaults from bricks set on bed radially (“true”
arches and vaults) but such construction necessitated some form of temporary
support (centering) during construction. Such brick work was ef ected in both
mud brick and burnt brick, but whereas normal construction in mud brick used
mud mortar, arcuated construction (particularly pitched brick construction) was
generally fashioned with lime, gypsum or bitumen mortar to increase the adhe-
sion and speed of setting.
In principle these techniques were available from Uruk times onwards, but
the earliest instances very largely concern utilitarian constructions like ovens,
wells, silos etc. Otherwise the earliest instances in the nature of buildings are under-
ground constructions, e.g. graves. With respect to vaulted rooi ng of free standing
buildings Heinrich's observations are signii cant. He states that the demonstrable
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