Download or read book Variational Approach to Probabilistic Finite Elements written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-23 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Probabilistic finite element methods (PFEM), synthesizing the power of finite element methods with second-moment techniques, are formulated for various classes of problems in structural and solid mechanics. Time-invariant random materials, geometric properties and loads are incorporated in terms of their fundamental statistics viz. second-moments. Analogous to the discretization of the displacement field in finite element methods, the random fields are also discretized. Preserving the conceptual simplicity, the response moments are calculated with minimal computations. By incorporating certain computational techniques, these methods are shown to be capable of handling large systems with many sources of uncertainties. By construction, these methods are applicable when the scale of randomness is not very large and when the probabilistic density functions have decaying tails. The accuracy and efficiency of these methods, along with their limitations, are demonstrated by various applications. Results obtained are compared with those of Monte Carlo simulation and it is shown that good accuracy can be obtained for both linear and nonlinear problems. The methods are amenable to implementation in deterministic FEM based computer codes. Belytschko, T. and Liu, W. K. and Mani, A. and Besterfield, G. Unspecified Center DYNAMIC STRUCTURAL ANALYSIS; ELASTOPLASTICITY; FINITE ELEMENT METHOD; SOLID MECHANICS; VARIATIONAL PRINCIPLES; DISPLACEMENT; LOADS (FORCES); MONTE CARLO METHOD; NONLINEARITY; PROBABILITY THEORY...