an engineering geological characterisation of tropical clays - GBV

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from intended structures; and/ or design and construct suitable foundation structures capable of
withstanding destabilising effects that may be caused by expansive ground movements.
Plate 1.4 Slightly tilting structure (towards the background) in a zone of black clays.
The available geological and soils maps covering the study area, are at their best, medium scale. For
engineering geological purposes, they can be described as regional and therefore less useful and
inadequate. Apart from presenting information mostly on lithology, geological structure and
stratigraphy of rock formations found, the maps show and give little on surficial deposits and soils.
There is also an obvious and total omission of information on geotechnical characteristics of the
soils and rocks. Within the current study, small scale engineering geological maps that are site
specific have been developed to provide and present important ground information and data on soils
in a continouos spatial form interpolated and extrapolated over the project area. The small - scale
detailed engineering geological soil maps will contain information sorted out by geotechnical
criteria for easy interpretation and readily application by geo - engineers and planners. The use of
these maps and application of contained information could also be extended to surrounding areas
with similar lithology.
Plates 1.5 (a) & (b) Foundation structures of light and low rise buildings located in black clays with
impeded drainage (foreground of Plate(b) with stagnant water).