Fuzzy Neural Network Forecast for the Liquefaction of the Saturated Sand under the Action of the Vibration Force

Based on the fact that the saturated sand may become liquefaction under the vibration force and the liquefaction potential has the fuzzy characteristics,the fuzzy mathematics and neural network algorithm were combined to construct a fuzzy neural network system for forecasting the liquefaction of the saturated sand.The system is a forwards-multilayer network,integrating the basic element and function of the traditional fuzzy logistic controller with the neural network that has the ability of distributed-study.It can obtain some basic parameters of the saturated sand liquefaction in the fuzzy inference through training with the practical engineering data.Thus,the inference system can be optimized.The fuzzy rules for the lique-faction of the saturated sand were set up with the fuzzy neural network system.The factors having little effect on the liquefaction of the saturated sand were eliminated and some factors having more effect on the liquefaction of saturated sand were given prominence to.Some parameters of the saturated sand,such as the relative density,the blow count of SPT,the overlaying effectiveness stress,the vibration force value,were used as the indicators to judge the liquefaction of the saturated sand and to forecast the possibility of the liquefaction of the saturated sand under the action of vibration force.The system was used in 35saturated sand samples of the practical engineering to forecast the liquefaction,and the results were of high consistency with the practical engineering.