Calculation of Concrete Minarets Frequency by Neural Network

摘要

Determination of natural angular frequency of concrete minarets by artificial neural network with various supporting conditions is general goal of this research. For the subject of neural network , training or learning algorithms are applied .The most famous of network structure which is back propagation algorithm is applied in this study. This algorithm is a systematic method for training multi layer artificial neural network . Back propagation algorithm is based on gradient descant which means that it moves downward on the error declination and regulates the weights for the minimum error. In this research, the real frequency of concrete minarets is calculated first using SAP2000 program and is defined as a goal function for neural network , so that all outputs of the network can be compared to this function and the corresponding error can be calculated and so the best function will selected. Then, a set of inputs including dimensions or specifications of arches are made using MATLAB program. After the determination of algorithm and quantification of the network, the phases of training and testing of the results are carried out and the output of the network is created. It is concluded that the performance of the neural network is optimum and the errors are less than 8%, so, the network trains in different manner. Furthermore the time of frequency calculations in neural network is less than real analysis time that calculated by SAP2000 software and its precision is acceptable (less than 12%).