Blast and Impact Loading and Response of Structures
Full Session with Abstracts
Simulation of structures under collapse requires accurate prediction of extreme limit states associated with material (tension necking) or global (buckling) instabilities. While spring or hinge models, fiber models, and continuum finite element models have been used to evaluate the behavior of a collapsing structure each of these methods have definitive drawbacks when attempting to simulate the post-peak behavior. A new method is developed which consists of a one-dimensional single line element that includes the effect of a localization. Cylindrical steel samples of different lengths were tested in tension and their response recorded with a DIC system to evaluate the development of the localization. The data was used to develop new simplified one dimensional line element that can capture the effect of the localization on the overall member post-peak response for members in tension. The model defines the pre- and post-peak stiffness of the line element through a quad-linear curve. Of particular importance is the definition of the bifurcation point which defines when unloading in the member initiates. This tension model is used in a simple truss structure to evaluate its effectiveness in evaluating post-peak response of a collapsing structure vs. other conventional methods. The data in this research lays the groundwork for developing simplified models for other types of loading such as flexure.