Discussion: Papers 5–7

DR W.G.K. FLEMING (General Reporter)

The problem of making satisfactory foundations with cast in situ piles in limestone where cavities are present must be familiar to engineers who have to deal with pile foundations in mining areas where the risk may be even greater because of negative friction due to general ground subsidence.

In Britain this particular difficulty has been avoided by using light metal liners through the soils above the cavity level to produce a friction free pile length.

Paper 6 deals with the use of continuous flight augers for the purpose of constructing piles through stable or unstable soils. The method has no connection with the old system of screw piling antl I think the term screw piling is perhaps unfortunate, because it has other connotations here.