A new method of estimating the ratio between in situ rock stresses and tectonicsudbased on empirical and probabilistic analyses

摘要

This paper describes a new procedure for assessing the ratio between in situ stresses in rock masses byudmeans of K (K=σH/σv, being σH and σv principal stress) and tectonics for purposes of engineering geologyudand rock mechanics. The method combines the use of the logic decision tree and the empirical relationshipudbetween the Tectonic Stress Index, TSI, and a series of K in situ values obtained from an extensive database.udThe decision tree considers geological and geophysical factors affecting stress magnitudes both on theudregional and local scale. The TSI index is defined by geological and geomechanical parameters. The methodudproposed provides an assessment of the magnitude of horizontal stresses of tectonic origin. Results forudseveral regions of Europe are presented and the possible applications of the procedure are discussed.