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Section 3: Slope stability hazards |
Transport Research Laboratory, Crowthorne, Berkshire RG45 6AU, UK
Minor slope failures receive much less publicity than major failures such as the Scarborough landslide, but can cause considerable damage and inconvenience. The engineering geologist is often required to carry out investigations into the failure and decide on appropriate remedial works in a very short timescale and with a limited budget. Difficulties of access to the slipped area limit the use of conventional ground investigation methods, but specialized lightweight methods such as hand-operated shell and auger boring can be very useful. It is important to define the geological situation as soon as possible, in order to understand the nature of the failure and the processes driving it. Remedial works which are appropriate can then be designed. Two case studies are presented to illustrate the process of investigation, design and construction; the collapse of a sewer on the bank of the River Tay in Perth, and the subsidence of a minor road on a steep hillside near Lanark. A gabion wall and mattress was adopted in the first case; a bored pile retaining wall in the second.
