Soil improvement and construction methods in peat - Geotechnics of Organic Soils and Peat - page 146

Figure 6.22 Imperfections due to geological behaviour ( after Poulos, 2005).
In many problems, there may exist 'imperfections' that arise for natural geological
or construction-related reasons, and which are generally unanticipated deviations from
the expected circumstances. While it may be possible to handle these imperfections
by appropriate analysis, the main difficulties are that the designer/analyst may not
recognize the existence of the imperfections during the design process, or else they
may only become manifest beyond the design process. Subsequent analysis may then
become either a remedial or a forensic exercise Poulos (2005).
The imperfections may include (among many others) layers which are not hori-
zontal or continuous, boulders within a soil layer, sloping bedrock, intrusions of rock
over limited areas of the site, cavities in limestone rock, or the presence of softer layers
below what might be regarded as suitable founding strata for the piles. Figure 6.22
illustrates some of these situations.
6.5.2.2 Inadequate ground investigation
These imperfections are generally related to those that arise from natural sources,
but are exacerbated because the site is not properly characterized. Inadequacies are
usually related to an insufficient number or depth of boreholes or probes to iden-
tify stratigraphic variations across the site, or inadequate testing to quantify the