Compliance with strength criteria for a model polymeric-composite grillage taking into account nonlinearity of the filler in different loading scenarios
This study compares different strength criteria in static loading simulation of a polymeric-composite grillage for different loading scenarios, boundary conditions and models of physical material behaviour. The paper discusses a detailed, structurally similar model of grillage made up by three-layered parts taking into account contact interaction (not the joint one) at the boundaries of bearing layers and the filler, with consideration of physically linear and nonlinear model of filler behaviour. The study applies volume-shell FE idealization. The loading (distributed and local)is simulated as per a step-wise procedure until the selected failure criteria are met, i.e. until limit loads (according to various hypotheses) are achieved. The paper gives examples of limit load calculations and their respective states of grillage for different variants of bearing circuit fastening and different loading types. The study yielded the fields of stress-strain parameters and the four principal complex failure criteria. The study discusses the effect of overall grillage compliance, as well as the effect of local (i.e. not affecting the compliant areas of the flooring) and distributed loading upon the limit state pattern of the structure and the level of its bearing capacity. It also estimates the effect of soft non-linearity of the filler upon limit stress-strain state pattern and limit load level, as well as upon the localization of «triggering» zones for non-dimensional criteria.