Random seismic response analysis of truss structures with uncertain parameters

This paper presents an approach called random factor method (RFM) for the random vibration analysis of seismic response of random truss structures. An antenna and a truss bridge with random material parameters and geometric dimensions are considered to illustrate the application of the RFM in the seismic response analysis of random structures under stationary or non-stationary random earthquake excitation. Using the RFM, the structural stiffness and mass matrices can respectively be described by the product of two parts corresponding to the random factors of structural parameters and the deterministic matrix. From the expressions of structural seismic random response in the frequency domain, computational expressions for the mean value and standard deviation of the mean square value of the seismic random displacement and stress response are developed by means of the random variable’s functional moment method and the algebra synthesis method. The influences of the randomness of the structural parameters on the structural seismic responses are investigated.