ABSTRACT
A good material for embankments consists of a well mixed blend of 20-30 per cent clay and 70-80 per cent well-graded sand and gravel. An embankment with less than 20 per cent clay is likely to leak, while one with more than 30 per cent is likely to shrink and crack. It is important to construct the embankment in dry weather, since puddles in the fill will be a source of future seepage and instability, and the fill must be compacted gently but firmly in layers not exceeding 150 mm. A typical profile of an impermeable soil embankment is shown in Figure 7.1, together with the water control mechanisms.
