Principles of verification and validation

This paper discusses the concepts of verification and validation in computational mechanics with special attention to structural fire engineering, by referring to recently published papers and guides on V&V that define some best practices and show directions for future development. The perspective of an analyst, who develops computational models, makes runs, and analyses numerical results mostly using software based on the finite element method, is presented. The considerations emphasize practical problems encountered in the V&V process, potential sources of errors and uncertainties, the importance of sensitivity study, new ideas regarding the relationship between validation and verification, differences between calibration and validation, new aspects of the validation metrics, and guides for designing validation experiments. The discussion is illustrated by computational problem examples

Benchmark example problems for beams at elevated temperatures

The paper presents development of a series of solutions for beams at elevated temperatures which are supposed to serve as benchmark problems for applications of computational models in fire structural engineering. Three cases of loading i.e. pure bending, central force, and uniformly distributed loading, are considered for a simply supported, and fixed on both ends beams at uniformly distributed elevated temperature varying in time. The results are provided in terms of the midspan deflection for specified loading levels and temperatures. The results mainly obtained using finite element (FE) models and two commercial codes, are verified through comparison with analytical solutions for simplified cases and through parametric study aimed to examine the effect of modelling parameters. The numerical results are subjected to mesh density study using the grid convergence index (GCI) concept