DYNAMIC RELIABILITY ASSESSMENT OF DOUBLE RANDOM VIBRATION SYSTEMS

A new dynamic reliability assessment method for double random vibration systems is proposed, in which the randomness involved in the structural parameters and excitation is taken into account. Through the probability density evolution method, the instantaneous probability density function of response of double random vibration systems is numerically obtained. Based on this method, an absorbing boundary condition, according to the first passage criterion, is imposed on the governing probability density evolution equation. The integration of the probability density function, which is obtained from the initial-boundary-value partial differential equation over the safe domain, will then give the dynamic reliability. A numerical algorithm is studied by combining the precise time integration and the finite difference method with TVD schemes. An 8-story frame with random parameters under random earthquake excitation is investigated to assess the dynamic reliability. The results are compared with those obtained by the Monte Carlo simulation. It is shown that the proposed method is of high accuracy and efficiency.