Search results for " Shakedown"
showing 3 items of 23 documents
Dynamic shakedown design of structures under repeated seismic loads
2013
The paper is devoted to the formulation of an optimal design (minimum volume) problem of elastic perfectly plastic structures subjected to suitable combinations of static (fixed) and dynamic (seismic) loads. The structure is constrained to simultaneously respect two different safety criteria; actually, it must exhibit an elastic shakedown behaviour for the combination of loads characterizing the serviceability conditions and it must prevent the instantaneous collapse for the highest expected load condition (combination of loads characterized by the presence of fixed loads and maximum expected intensity of seismic action). The shakedown limit behaviour for the optimal structure will be impos…
Comparison between unrestricted dynamic shakedown design and a new probabilistic approach for structures under seismic loadings
2014
The paper concerns a study related to the comparison between two different approaches utilized for the formulation of an optimal shakedown design problem for elastic plastic frame structures subjected to a combination of fixed and seismic loading. The first formulation utilizes the unrestricted dynamic shakedown theory, while the second one is based on a new probabilistic approach. The comparison is effected in terms of mathematical formulations, in terms of adopted loading models and in terms of numerical results. The performed applications are related to plane steel frames.
Probabilistic Evaluation of the Adaptation Time for Structures under Seismic Loads
2016
Abstract In this paper, a probabilistic approach for the evaluation of the adaptation time for elastic perfectly plastic frames is proposed. The considered load history acting on the structure is defined as a suitable combination of quasi-statical loads and seismic actions. The proposed approach utilizes the Monte Carlo method in order to generate a suitable large number of seismic acceleration histories and for each one the related load combination is defined. Furthermore, for each load combination the related adaptation time is determined, if any, as the optimal one for which the structure is able to shakedown under the unamplified applied actions. A known generalized Ceradini's theorem i…