by P J Whyley, Manstock Geotechnical Consultancy Services and R W Sarsby, Bolton Institute
This paper was first published in GE’s May 1992 issue.
Vibration from piling operations will always be of a temporary nature but the disturbance caused may result in substantial nuisance to the surrounding population and permanent damage to property. Either factor might lead to restraints on the working method that result in additional costs or even, in extreme circumstances, curtailment of activity. The Control of Pollution Act (1974) gives local authorities very wide ranging powers with regard to construction vibrations. Part 4 of the revised standard BS5228 (1991)was formulated specifically to cover ground vibrations from construction operations and should provide particular benefit regarding piling induced vibrations. It is vital for the feasibility of piling works to be assessed at all stages in the development of a site (ie concept, design, tender, construction). There is a lack of definitive guidance from which vibrations can be predicted, probably because of the complexity of the inter-relationships between ground and pile. A suggested method of predicting the probable level of vibrations from piling operations at any site is given below. Information on a number of vibration measurements made in the vicinity of driven piling are provided from case histories. A range of energy inputs, ground conditions and penetration configurations are covered by the spectrum of results.