ABSTRACT

Inevitably the actual load-penetration response will differ from the prediction. There are uncertainties attached to the parameters on which the prediction is based, on the calculation methods employed and on the measurements made in the field. The engineer on site is therefore faced with a dilemma: at what stage are the discrepancies between the measured behaviour and the prediction sufficiently large that “alarm bells ring”, and further action is necessary to assure (if possible) the safety of the rig.