Civil Engineering Reference
In-Depth Information
glutinous yielding mud. And it may be said in advance Egyptian conservatism
meant that development in artii cial foundations did not keep pace with this dete-
rioration of natural foundations.
Before attempting to outline the use of stone for foundations in antiquity, it
is worth remarking that modern foundation science is, in fact a recondite study
which can not be broached here. A classic presentation of the subject is contained
in the works of K. Terzaghi (cf K. Terzaghi
et al
., “Soil Mechanics in Engineering
Practice”).
As a preliminary it is possible to roll up somewhat the question of ancient stone
foundations. h e extreme worthlessness of natural foundations is ground which is
intrinsically instable—i.e. subject to l ow, creep or slump etc. irrespective of load.
Measures taken to remedy this are in the nature of soil stabilisation. h ese do not
involve stone, but are either chemically based soil science (e.g. intermixing ashes
and lime to bind plastic soil together and make it rigid) or involve timber piling
which mechanically compresses the soil and promotes immobility by increased
friction. h e former was practiced on tells in the ancient Middle East, and the
latter was common in Roman building and engineering.
h e earliest use of stone in monumental construction occurs in the megalithic
monuments of Western Europe during the 5th Millenium BC. h e massive slabs
and baulks used as uprights in these monuments do not rest on artii cial founda-
tions. It is interesting to note that they are treated exactly as heavy wooden baulks
or posts—i.e. they are sunk to a considerable depth in i rm unyielding soil to
guarantee their stability. And here it is apposite to recall that megalithic building
proceeded from a background in wooden structures, e.g. there were wood henges
as the immediate predecessors of Stonehenge.
In fact the i rst appearance of stone foundations was in the predominantly mud
brick building of the Ancient Middle East, but it was not an original component of
this construction. h e earliest pre-pottery Neolithic habitation (ca 8th Millenium
BC) was an emplacement of round plan sunk ca 50 cms or more below ground level
surrounded by a mud brick barrier wall to a certain height (= h e Round House).
Here, it may be appreciated, the concept of foundations was extraneous. However
there followed an ecumenical evolution away from the original “round house” style
of building, whereby the round plan gave place to a rectangular plan; l ooring at
surface level was substituted for sunken emplacements and the original barrier
walling became a load bearing structure supporting the roof. h e sum of these
developments imported that the mud brick walls were provided with one or more
courses of rubble stone as footings at ground or below ground level (Aurenche,
La Maison Orientale I
, pp. 95-101). h is transformation was fully established by
later Neolithic and Chalcolithic times, i.e. by ca 5th Millenium BC. h ereat er it
was the norm for mud brick walling to be based on rubble footings.
Stone
founda-
tions
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