Soil classification by fuzzy generating rules and Iran standard no. 2800

Classification of soil is a function of the geological conditions of the region, which according to the 2800 earthquake standard, is itself a function of average shear wave velocity, average standard penetration number and average undrained shear strength in cohesive soils in different layers to a depth of 30 meters from the surface. Due to the uncertainties in the mentioned parameters and also considering that the values of these parameters in the real material are not the same as the values obtained from the experimental tests, so for this and determination of these parameters requires the use of statistical and probabilistic methods. Due to the computational complexity of statistical and probabilistic methods, in this research, a fuzzy inference system has been used to the decision of the choice of soil type, which can consider uncertainties without the need for complex mathematical calculations. For this purpose, after determining the effective parameters in determining the soil type, triangular membership functions were selected for them and finally, a fuzzy inference system was designed. A comparison of the results of this study with the results of field research shows the efficiency of the proposed fuzzy inference system.