Engineering Geology

E n g i n e e r i n g G e o l o g y
Figure 3.5
Geodurability classification chart for intact rock. Note: (i) e D is determined from oven-dried (105∞C) to 24-h-saturation condition.
(ii) e D is plotted as the range and mean of the test results. (iii) strength ratings are according to Bieniawski (1974)
(after Olivier, 1979). With kind permission of Elsevier.
Olivier (1979) proposed the geodurability classification, which is based on the free-swelling
coefficient and uniaxial compressive strength (Fig. 3.5). This classification was developed to
assess the durability of mudrocks.
Engineering Classification of Weathering
The early stages of weathering are usually represented by discoloration of the rock material,
which changes from slightly to highly discoloured as the degree of weathering increases.
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