Prediction on uniaxial compression strength of rocks with X-ray computed tomography

Uniaxial compression stress(UCS) is the important parameters of rock mass excavation and its stability analyzing in the underground engineering. UCS determination of rocks is really necessary to provide some scientific guidance for engineering excavation. This study focuses on how to get UCS of rocks with X-ray computed tomography. Five mudstone specimens for example are scanned with using of medical X-ray CT device. Then, volume data characteristics of different density materials have been identified and extracted from CT series images of rocks. UCS of rocks is quantitated with cumulative CT numbers of different density materials in X-ray series images. A new method which is called X-ray CT images prediction(X-CTIP) is proposed for determining UCS of rocks. The results show that cumulative CT numbers of mudstone composition range from 1 760 to 2 560 HU, which determining strength ratio is 0.94 to 0.96 and is also quadratic with UCS. Hence, the key task for predicting UCS of rocks extracted the CT cumulative value from X-ray sequence images and then re-calculated the corresponding UCS. The X-CTIP method can be used as determining relatively accurate UCS of rocks with a single composition, better homogeneity and integrity. © 2019, Science Press. All right reserved.