Soft computing method for assessment of compressional

The physico-mechanical properties of rocks and rockmass are decisive for the planning ofmining and civil engineering projects. the schmidt hammer rebound number (rn), slake durability index(sdi), uniaxial compressive strength (ucs), impact strength index (isi) and compressive wave velocity(p-wave velocity) are important and pertinent properties to characterize rock mass, and are widely usedin geological, geotechnical, geophysical and petroleum engineering. the schmidt hammer rebound can beeasily obtained on site and is a non-destructive test. the p-wave velocity and isotropic properties of rockscharacterize rock responses under varying stress conditions. many statistics based empirical equationshave been proposed for the correlation between rn, sdi, ucs, isi and p-wave velocity. the artificial neuralnetwork (ann), fuzzy inference system (fis) and neuro-fuzzy system are emerging techniques that havebeen employed in recent years. so, in the present study, soft computing is applied to predict the p-wavevelocity. 85 data sets were used for training the network and 17 data sets for the testing and validation ofnetwork rules. the network performance indices correlation coefficient, mean absolute percentage error(mape), root mean square error (rmse), and variance account for (vaf) are 0.9996, 0.744, 25.06 and99.97, respectively, which demonstrates the high performance of the predictive capability of the neuro-fuzzy system.