3 resultados para two-dimensional abstraction
em AMS Tesi di Dottorato - Alm@DL - Università di Bologna
Resumo:
This thesis reports a study on the seismic response of two-dimensional squat elements and their effect on the behavior of building structures. Part A is devoted to the study of unreinforced masonry infills, while part B is focused on reinforced concrete sandwich walls. Part A begins with a comprehensive review of modelling techniques and code provisions for infilled frame structures. Then state-of-the practice techniques are applied for a real case to test the ability of actual modeling techniques to reproduce observed behaviors. The first developments towards a seismic-resistant masonry infill system are presented. Preliminary design recommendations for the seismic design of the seismic-resistant masonry infill are finally provided. Part B is focused on the seismic behavior of a specific reinforced concrete sandwich panel system. First, the results of in-plane psuudostatic cyclic tests are described. Refinements to the conventional modified compression field theory are introduced in order to better simulate the monotonic envelope of the cyclic response. The refinements deal with the constitutive model for the shotcrete in tension and the embedded bars. Then the hysteretic response of the panels is studied according to a continuum damage model. Damage state limits are identified. Design recommendations for the seismic design of the studied reinforced concrete sandwich walls are finally provided.
Resumo:
This thesis, after presenting recent advances obtained for the two-dimensional bin packing problem, focuses on the case where guillotine restrictions are imposed. A mathematical characterization of non-guillotine patterns is provided and the relation between the solution value of the two-dimensional problem with guillotine restrictions and the two-dimensional problem unrestricted is being studied from a worst-case perspective. Finally it presents a new heuristic algorithm, for the two-dimensional problem with guillotine restrictions, based on partial enumeration, and computationally evaluates its performance on a large set of instances from the literature. Computational experiments show that the algorithm is able to produce proven optimal solutions for a large number of problems, and gives a tight approximation of the optimum in the remaining cases.
Resumo:
The present manuscript focuses on out of equilibrium physics in two dimensional models. It has the purpose of presenting some results obtained as part of out of equilibrium dynamics in its non perturbative aspects. This can be understood in two different ways: the former is related to integrability, which is non perturbative by nature; the latter is related to emergence of phenomena in the out of equilibirum dynamics of non integrable models that are not accessible by standard perturbative techniques. In the study of out of equilibirum dynamics, two different protocols are used througout this work: the bipartitioning protocol, within the Generalised Hydrodynamics (GHD) framework, and the quantum quench protocol. With GHD machinery we study the Staircase Model, highlighting how the hydrodynamic picture sheds new light into the physics of Integrable Quantum Field Theories; with quench protocols we analyse different setups where a non-perturbative description is needed and various dynamical phenomena emerge, such as the manifistation of a dynamical Gibbs effect, confinement and the emergence of Bloch oscillations preventing thermalisation.