摘要
The behavior of rock masses is influenced by a variety of forces,with measurement of stress and strain playing the most critical roles in assessing deformation.The laboratory test for determining strain at each location within rock samples is expensive and difficult but rock strain data are important for predicting failure of rock material.Many researchers employ AI technology in order to solve these difficulties.AI algorithms such as gradient boosting machine(GBM),support vector regression(SVR),random forest(RF),and group method of data handling(GMDH)are used to efficiently estimate the strain at every point within a rock sample.Additionally,the ensemble unit(EnU)may be utilized to evaluate rock strain.In this study,3000 experimental data are used for the purpose of prediction.The obtained strain values are then evaluated using various statistical parameters and compared to each other using EnU.Ranking analysis,stress-strain curve,Young’s modulus,Poisson’s ratio,actual vs.predicted curve,error matrix and the Akaike’s information criterion(AIC)values are used for comparing models.The GBM model achieved 98.16%and 99.98%prediction accuracy(in terms of values of R2)in the longitudinal and lateral dimensions,respectively,during the testing phase.The GBM model,based on the experimental data,has the potential to be a new option for engineers to use when assessing rock strain.
