Regression analyses were carried out using SPSS 16 statistical software, which offers a stepwise regression method. It is established that the elastic modulus and MR in very strong carbonate samples are more correlated with p - UCS combination and ea max, respectively, than in weak-to-strong samples. An elastic modulus (also known as modulus of elasticity) is a quantity that measures an object or substance's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it. 1. The GEP model was developed using data sets of 317 rock specimens obtained from an experimental study. As can be clearly seen in these figures, there is no relationship between the predicted and observed variables, and the results obtained by these methods are very different from the experimental results (). As a result of the evaluation of these results, the GEP model was determined as the best applicable model for predicting in comparison with MRA and . This parameter is decisive in tunnel project, rock destruction and drilling, slope consistency, pillar configuration, embankments, and many other civil and mining applications [3]. For GEP formulation, the fitness of an individual program is measured bywhere is the range of selection, is the value returned by the individual chromosome for performance case (out of fitness cases), and is the target value for fitness case . It was shown that the GEP model considerably outperforms compared to other soft computing systems mentioned above. On the other hand, the values of the MRA, URA (a power model where is the independent variable), and models are 0.68, 0.72, and 0.43, respectively. In these multivariable and univariate models, the highest regression coefficient () value is 0.69 for model 4 (Table 2) and 0.72 for the power-type model (Table 3), where is an independent variable. Two strain gauge rosettes, consisting of two gauges each, were bonded to the surface of each specimen at two directly opposite points located half-way between the specimen ends for the measurement of axial and circumferential strains, which were recorded at 1-s gaps performing a static data logger. The velocities of compression () and shear () waves were recorded in cylindrical core samples applying the high-frequency ultrasonic pulse technique proposed by ASTM [7]. The reservoir rock for many geothermal projects in the Upper Rhine Graben, such as those at Soultz-sous-Forêts and Rittershoffen (both France), is porphyritic granite. To build the model, results of 317 specimens were used in training, testing, and validation. According to, the elastic modulus of granite varies from 2.59 GPa to 88.79 GPa, and in the case of sandstone from 3.4 GPa to 71.7 GPa. For these reasons, measurements are not common in rock engineering projects. It can be used with a Matest high stability frame with capacity of 2000, or 3000 kN coupled to the Automatic Servo-controlled system “Servo-Plus Evolution” (mod. Learning from experience and deriving the information is one of the essential properties of soft computing techniques. Modulus of elasticity or Young's modulus (E):The ratio of stress to corresponding strain below the proportionality limit of a material. 1, pp. Because of these results, there is no need to assess the validity of these models further. It must be appreciated that predicting from is ultimately an inverse problem. Since the system can find the optimal solution by itself, it can be considered as the advantage of this type of fitness function [24, 32, 33]. 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