The Analysis of Geometrically Nonlinear Elastic-Plastic Space Frames / Tampriai Plastinių Geometriškai Netiesinių Erdvinių Rėmų Analizė

Abstract

The establishment of the real stress-strain state of the structure is one of the most important problems for designing and undertaking the reconstruction of building constructions as well as making calculations for the purpose of optimizing cross-sections of various structural elements. This task can be achieved by analysing the structure as a geometrically nonlinear system (refusing an assumption of small displacements) and taking into consideration plastic deformations. Modern computer technologies and mathematical tools enable us to perform strength analysis of space structures and to increase the accuracy of stress-strain state analysis. The present paper develops a technique for constructing a finite element tangent matrix for the nonlinear analysis of the space frame structure aimed at determining plastic deformations. The mathematical models of the problems based on static and kinematic formulations using the dual theory of mathematical programming were created for analysis. Strength conditions presented in construction codes and specifications AISC-LRFD and suggested by other researchers (e.g. Orbison's strength conditions) are used in the formulations of the analysed problems. The mathematical models of the considered problems are tested by calculating a two-storied space frame. The results of the performed analysis are compared with data obtained within the studies conducted by other researchers.

Research on Probability for Failures in Vw Cars During Warranty and Post-Warranty Periods / „vw“ Markės Automobilių Gedimų Tikimybės Garantiniu Ir Pogarantiniu Laikotarpiu Tyrimas

“…Šiame etape numatomos transporto priemonės savybės: saugumas, patogumas, pravažumas, degalų sąnaudos, unifikavimo laipsnis, remontavimo galimybės, patikimumas ir kitos (Karkauskas, Popov 2011;Dyakov, Prentkovskis 2008). Transporto priemonės patikimumo garantijos, už-fiksuotos jos projekte, būna efektyvios tik tuomet, kai transporto priemonė pagaminama tiksliai pagal brėžinį ir numatytą technologiją (Mickūnaitis 2006).…”

The problems of optimal design in the automotive industry

“…Different requirements are specified to a wheeled machine depending on its purpose; they are formed in the terms of reference. The most important ones are process-ability, unification, and qualitative operational indicators such as: fuel efficiency, off-road capability, control, reliability, safety, easy maintenance and repair, and low cost of manufacturing and operation (Duggirala et al 1994;Lin, Lin 2001;Xu et al 2007;Sekulski 2009Sekulski , 2010Khoei et al 2010;Karkauskas, Popov 2011;Collignan et al 2012;Gottvald, Kala 2012;Kou et al 2012, etc. ).…”

Influence of the Column Web Panel Behaviour on the Characteristics of a Beam-to-Column Joint

“…The real behaviour of the framework allows designing better fitting and safer structures, herewith reaching the economic benefit (Misiū naitė et al 2012;Kala 2012;Karkauskas, Popov 2011;Turkalj et al 2012). Recently, the topic of semi-rigid joints has been increasingly investigated.…”