TN10. Example of a submarine slope failure during installation of piles

One interesting example of a submarine slope failure during the installation of piles for a number of jetties may be mentioned.

The strata at this locality in the Middle East consisted of very recent deltaic and estuarine deposits, some 30 to 35m deep and overlying decomposed bed rock. The alluvial deposits consisted of alternating bands, lenses or layers of silty clays, silts and sands, laminated and with much horizontal interbedding.

Prior to construction, ground level was about 2.5m. This was raised to +3.8m along the line of the relief piles, which were installed first, whilst the sea-bed was dredged to an angle of