Buckling Analysis and Stability of Compressed Low-Carbon Steel Rods in the Elastoplastic Region of Materials

[EN] This paper presents new approaches for solving a problem of the stability of compressed rods in the elastoplastic working region of materials. It is known that the columns of buildings, supports of engineering devices, drill rods of oil, and gas extraction industry may be subjected to significant risk of stability loss. Nowadays, there are design methods based on test results defining the relations (e.g., critical stresses-slenderness) to avoid this risk due to stability loss, but the precision and limits of definition are not always known. The main objectives of the study were to develop new approaches that would allow specifying the values of critical stresses of compressed elements beyond the proportional limit. The problem of stability of the compressed elements in the elastoplastic region was studied according to the stability theory. The authors suggested an original approach to the issue; in particular, the determination of values of the critical stresses and the finding of the points of the bifurcation were carried out by the tangent established by experimental results and by the approximation of the so-called double modulus. Comparative analysis showed the advantage of the proposed approach, particularly that the new critical curves were located below the curves of Engesser-Karman and Shanley and above the critical curves established by building codes. A new approach for the determination of critical stresses in the elastoplastic region was developed through which the structural reliability and economic efficiency was increased by almost 12% compared to the existing approaches.This research was financially supported by the Erasmus Mundus Action 2 Project Electra: Enhancing Learning in ENPI Countries through Clean Technologies and Research related Activities (project: ELEC1400294) and the Spanish Ministry of Economy and Competitiveness, along with FEDER funding (project: BIA2017-85098-R).Partskhaladze, G.; Mshvenieradze, I.; Medzmariashvili, E.; Chavleshvili, G.; Yepes, V.; Alcalá-González, J. (2019). Buckling Analysis and Stability of Compressed Low-Carbon Steel Rods in the Elastoplastic Region of Materials. Advances in Civil Engineering. 2019:1-9. https://doi.org/10.1155/2019/7601260S192019Braun, D. J. (2008). On the optimal shape of compressed rotating rod with shear and extensibility. 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Heuristic Optimization of a New Type of Prestressed Arched Truss

[EN] This paper represents new approaches for calculating, designing, and optimizing prestressed arched trusses with a tie member. Structural systems with long spans, such as trusses, beams, frames, etc., are subjected to a considerable/substantial risk of losing load-carrying capacity because of the different types of loads used. Some traditional design methods define the values of prestressing force in the tie member and internal forces in the truss elements to avoid this load capacity loss. However, the accuracy and limits of the determination of the forces are not necessarily known. The authors offer a new type of prestressed arched truss and some new approaches in the design and calculation process to solve these disadvantages. The study¿s main objectives were to design an innovative and new geometric form of prestressed arched truss, which allows the development of high-value prestressing force, to optimize a new truss for reducing self-weight, increasing load-carrying capacity compared to its analogs. The force, stiffness matrix, and simulated annealing methods were used during the study. A new advance to the optimization of prestressed arched truss suggested by the authors reduces the self-weight and improves the load capacity of the truss by 8¿17%, depending on the span.This research was funded by the Erasmus Mundus Action 2 Project Electra: Enhancing Learning in ENPI Countries through Clean Technologies and Research related Activities (project: ELEC1400294), Erasmus+ program InnoCENS-Enhancing innovation competences and entrepreneurial skills in engineering education (project: 573965-EPP-1-2016-1-SE-EPPKA2-CBHE-JP). Grant PID2020-117056RB-I00 funded by MCIN/AEI/ 10.13039/501100011033 and by ERDF A way of making Europe.Partskhaladze, G.; Alcalá-González, J.; Medzmariashvili, E.; Chavleshvili, G.; Surguladze, B.; Yepes, V. (2022). Heuristic Optimization of a New Type of Prestressed Arched Truss. Materials. 15(22):1-20. https://doi.org/10.3390/ma15228144120152

Trademarks, Certification Marks and Technical Standards

The names of many technical standards such as Wi-Fi, Bluetooth and DVD have become household terms known throughout the developed world. This chapter describes different approaches that have been taken with respect to the naming and legal protection of technical standards, ranging from those that are wholly unregulated to those that are administered under strict certification and compliance regimes. It concludes by questioning the need for aggressive protection of marks that exist largely to inform consumers about technical product features rather than the source of standards themselves

Regulating European Standardisation through Law : The Interplay between Harmonised European Standards and EU Law

Standardisation is one of the oldest human activities. Industrial revolution and electro-technical advancements have further increased the importance of standardisation. Nowadays standards regulate our daily life not only through the products and services we use, but also directly as laws. In the EU, Harmonised European Standards (HESs) are used in legislation—occupying the law’s domain—but at the same time, the HESs are not produced through the same manner as laws—i.e. by democratically elected individuals. This thesis investigates the legal status of these technical rules under EU law and whether and how EU law can regulate and hold European standardisation accountable by means of judicial review. In answering these questions, I admit that there are different visions of how the HESs used in EU legislation can be seen, which influences how we regulate and hold accountable European standardisation. Notwithstanding these differences, one thing is clear: if we accept that the HESs play an important role in regulating health, safety, and the environment, and at the same time are not produced by democratically elected individuals, then the least the law can do is to regulate and ensure the legal accountability to perfect the standardisation process, to make it more accountable and ‘public-regarding.’ In exploring these issues, I propose conceiving of the EU law as a ‘gentle civiliser’ for the standardisation process. In particular, I argue that the EU economic law could be a backdoor through which constitutional principles of good governance reach and regulate the European standardisation system. To do so, the judicial review of the European standardisation system at the EU level should be a process oriented as to trigger a more inclusive, open, and transparent standardisation process; in other words, judicial review should be a catalyst for a ‘public-regarding’ standardisation

Novel approach to indirect actions of military theory

The major object of the study of the military theory is a mili-tary action. There are many variants of its definition, ranging from simple rather complex interpretation. According to general consensus military action is a result of human civilization, of armed confrontation between the formal and informal groups of society, their mutual apparition and offering of resistance to one another.Introduction; Fighting capasity of the combatants; Dynamic and geometrical parametrs of the fighting systems; Systematization of dynamic processes of indirect actions; Interdependency of strategy, operational art and Tactics; Matematical modeling of military planning space; References