About the confidence limits of the joint set parameters

Abstract

A joint set is characterised by several geometrical parameters - attitude, intensity, area, and aperture -, which have to be determined from measurements performed on natural or man­made observation surfaces of the rock mass. However, many engineering problems cannot be adequately solved if only the most probable values of the involved paran1eters are known, as the search for safe solutions asks for the analysis of all unfavourable, but still possible scenarios. The knowledge of the confidence limits of the estimates of the different joint set parameters allows the engineer to detemtine which unfavourable combinations of those parameters have still a reasonable probability of occurrence, and, thus, must be taken into consideration in the design of the work. The paper gives information about the confidence limits for some estimates of the different joint set parameters.