an engineering geological characterisation of tropical clays - GBV
an engineering geological characterisation of tropical clays - GBV
an engineering geological characterisation of tropical clays - GBV
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8.4 Linear shrinkage<br />
The spatial variation <strong>an</strong>d distribution <strong>of</strong> values <strong>of</strong> linear shrinkage determined in this study are<br />
presented in Table (8.1) <strong>an</strong>d Figures (8.7a & b).<br />
Linear shrinkage variation; < 0,5m depth<br />
30<br />
Linear shrinkage (%)<br />
25<br />
20<br />
15<br />
10<br />
5<br />
Pr<strong>of</strong>ile A<br />
Pr<strong>of</strong>ile B<br />
Pr<strong>of</strong>ile C<br />
Pr<strong>of</strong>ile D<br />
Pr<strong>of</strong>ile E<br />
0<br />
0 2000 4000 6000 8000 10000 12000<br />
Dist<strong>an</strong>ce along pr<strong>of</strong>ile (m)<br />
Fig. 8.7a. Linear shrinkage variation across the study area for the depth <strong>of</strong> less th<strong>an</strong> 0,50m (north-south dist<strong>an</strong>ce: 4000 m).<br />
Black <strong>clays</strong> <strong>of</strong> less th<strong>an</strong> 0,50m depth generally exhibit little variation in linear shrinkage<br />
values along each <strong>of</strong> the five field pr<strong>of</strong>iles across the study area (Fig. 8.7a); with percentage<br />
values <strong>of</strong> 24-27, 23-26, 23-29, 24-27 <strong>an</strong>d 23-25 determined for pr<strong>of</strong>iles A, B, C, D <strong>an</strong>d E,<br />
respectively. On the whole, soil thicknesses in this depth interval across the study area exhibit<br />
linear shrinkage values <strong>of</strong> between 23-29%, with a r<strong>an</strong>ge <strong>of</strong> 6% as well as mode, medi<strong>an</strong> <strong>an</strong>d<br />
me<strong>an</strong> values <strong>of</strong> 25%. The distribution is also characterised by a st<strong>an</strong>dard deviation <strong>of</strong> 1,38<br />
<strong>an</strong>d vari<strong>an</strong>ce <strong>of</strong> 1,89.<br />
Linear shrinkage variation; 0,50m <strong>an</strong>d more<br />
30<br />
25<br />
Linear shrinkage (%)<br />
20<br />
15<br />
10<br />
5<br />
Pr<strong>of</strong>ile A<br />
Pr<strong>of</strong>ile B<br />
Pr<strong>of</strong>ile C<br />
Pr<strong>of</strong>ile D<br />
Pr<strong>of</strong>ile E<br />
0<br />
0 2000 4000 6000 8000 10000 12000<br />
Dist<strong>an</strong>ce along pr<strong>of</strong>ile (m)<br />
Figure 8.7b. Linear shrinkage variation across the study area at depths <strong>of</strong> 0,5m <strong>an</strong>d greater (north-south dist<strong>an</strong>ce: 4000 m).