A large number of soils are considered to be problematic (eg. Collapsible soils, Expansive soils, Peat, Silty soils, Liquefiable soils). The talk will briefly cover the factors that lead to soils being considered to be problematic (soil type, site investigation, testing, modelling, experience).
A case study of an unusual problematic residual soil, limonite from New Caledonia will be presented to illustrate some of the challenges. Limonite is a residual soil produced by the decomposition of magnesium silicate (olivine) rocks in tropical environments. During weathering most of the original rock is leached away leaving only its iron content, which is precipitated out in the form of iron sesqui-oxides to create a soft and highly porous soil up to 70 m deep. This material presents challenges in classification, compactability and in- situ has a high variability in strength and stiffness.
The talk will conclude with some thoughts on the need to recognise the challenges presented by the ground, and how we can remove the problem from problematic soils
-definition of problematic soil
Is the soil that causes additional problems from the engineering point of
view as a result of the circumstances of its composition or a change in
environmental conditions. There are many types of soil, but we will offer
detailed the most common kinds in Egypt, namely