Cho W Solomon To
University of Nebraska, USA
Title: Finite nonlinear responses of uncertain shell structures under non-stationary random excitations
Biography
Biography: Cho W Solomon To
Abstract
Presently, various common approaches in dealing with engineering systems that contain uncertain parameters are essentially
based on probabilistic models, partially or entirely employing the Monte Carlo Simulation (MCS) and hierarchical uncertainty
quantification applying Bayesian inference. Another common category of approaches involves application of perturbation
approximation techniques, such as the so-called Stochastic Finite Element Method (SFEM) and Probabilistic Finite Element Method
(PFEM). Many of these approaches can only deal with systems with small uncertainties or variations of system parameters and
properties. The investigation reported here is concerned with two main objectives. The first main objective is the development of an
approach that is capable of providing finite responses of shell structures with large uncertainties and under non-stationary random
excitations. The latter are encountered during, for example, the re-entry of space shuttles, and the launching of high power rockets
with heavy and expensive payloads. The present approach consists of the FEM and the Stochastic Central Difference (SCD) method
that was previously developed by the author and his associates. The second main objective is the study of the difference between
finite random responses of shell structures with small and large uncertain properties. For tractability and readily available results
for comparison, the nonlinear shell structure studied by the author (2009) is employed in the present investigation. It should be
emphasized that in the present investigation the nonlinear spherical cap is hinged circumferentially. Large uncertainties in modulus
of elasticity and thickness of the shell structure are included in the present investigation.