Over one-seventh of the land area of Ireland is covered by bog. In addition, soft deposits occur near lakes, rivers and estuaries. Because many Irish cities and towns are situated near rivers, the problems, both technical and economic, presented by alluvial deposits are of considerable importance. This report describes the nature and mode of occurrence of these compressible soils, together with some of the morphological and environmental factors which determine their structural behaviour. Methods of identifying these soils are discussed and typical results given for the more common laboratory and in-situ tests. Special attention is given to the classical terzaghi oedometer test which is the most widely used basis for the preparation of forecasts of the behaviour under load of a deposit. The test is shown to be deficient, and a description is given of some of the better known attempts at improvement of its usefulness in the preparation of forecasts.
Samenvatting