Wyniki wyszukiwania - Biblioteka Nauki

1

Metodyka oceny odporności dynamicznej wybranych obiektów mostowych na terenie LGOM

100%

Ciurej H. , Rusek J.

Czasopismo Techniczne. Budownictwo

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2006

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tom R. 103, z. 13-B

31-57

PL

W niniejszym artykule przedstawiono metodykę oceny odporności dynamicznej obiektów mostowych poddanych oddziaływaniom drgań pochodzenia górniczego. Sformułowano warunki opisujące tę odporność oraz podano wyniki obliczeń dynamicznych dla 21 obiektów mostowych położonych na terenie LGOM, które w trakcie wstępnej analizy zakwalifikowano, ze względu na ich cechy dynamiczne, do pięciu różnych klas.

EN

The paper presents methodology of estimation of dynamic resistance of bridges loaded by ground motion caused by mining impacts. Consequently there have been formed several conditions describing dynamic resistance of bridges and shown results of dynamics analysis for 21 bridges placed on yield of LGOM. Group of bridges, depend on dynamics characteristics, classified into 5 different categories.

2

The reasons for hybrid light pole failures – an analytical study

63%

Jastrzębski D. , Niesterowicz B.

Technical Transactions

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2019

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tom Vol. 116, iss. 4

133--146

EN

This paper presents the results of a durability analysis of a hybrid light pole. The developed model includes a supporting structure of a pole with photovoltaic panels, a wind turbine and a boom with a light case. Due to various operating conditions, these poles may be characterised by a different configuration of the mutual spatial distribution of individual components. This results in a large diversity in the analysis results, hence the fact that the research was performed for the selected configuration variant for which the most unfavourable operating conditions were forecasted. In order to reveal potential stress concentration areas, a series of structural analyses was applied using the finite element method. As part of the work, changes to the supporting structure of the pole were proposed and to confirm the possibility of improving the resistance of the structure, additional analyses were conducted.

PL

W pracy przedstawiono wyniki modelowych badań wytrzymałościowych hybrydowego słupa oświetleniowego. W opracowanym modelu uwzględniono konstrukcję nośną słupa wraz z panelami fotowoltaicznymi, turbiną wiatrową oraz oprawą oświetleniową. Ze względu na zróżnicowane warunki eksploatacyjne słupy te mogą charakteryzować się odmienną konfiguracją wzajemnego przestrzennego rozmieszczenia poszczególnych komponentów. Powoduje to duże zróżnicowanie wyników analiz, stąd badania przeprowadzono dla wytypowanego wariantu konfiguracji, dla którego prognozowano najbardziej niekorzystne warunki eksploatacji. W celu ujawnienia potencjalnych miejsc koncentracji naprężeń zastosowano szereg analiz konstrukcji metodą elementów skończonych. W ramach pracy zaproponowano zmiany w konstrukcji nośnej słupa oraz przeprowadzono analizę potwierdzającą możliwość poprawy odporności konstrukcji.

3

Introduction and seismic performance investigation of the proposed lateral bracing system called "OGrid"

63%

Boostani M. , Rezaifar O. , Gholhaki M.

Archives of Civil and Mechanical Engineering

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2018

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tom Vol. 18, no. 4

1024--1041

EN

In this paper proposed bracing systems for earthquake resistant steel structures are introduced and studied through an experimental program and FEM (finite element method) numerical analysis. These proposed bracing systems called OGrid, by two types as the OGrid-I and the OGrid-H, are braced frames with circular braces connected to MRF (moment resisting frame) with joint connections. Linear and nonlinear behavior of the new OGrid bracing systems are studied and compared with X-bracing system, and MRF in one story base models. To achieve the linear and nonlinear behavior of models, response spectrum analysis and nonlinear static (pushover) analysis are used by FEM. Results showed that new OGrid bracing systems have appropriate vibration period, elastic stiffness and displacement. Absorbed energy of the proposed OGrid-I and OGrid-H bracing systems in comparison with MRF is 1.74 times and in comparison with X-bracing system is 34.8 times. The OGrid-I and OGrid-H bracing systems have more ductility and have great distance between relative deformation of the structure in yield strength level and the maximum relative deformation of structure after entering the plastic region, which cause to dissipate much lateral loads, and there is a great distance between first hinge formation and the moment that structure collapses.

4

Reliability-based dynamical design of a singular structure for high energy physics experiments

63%

Palma R. , Torrent J. , Pérez-Aparicio J. L. , Ripoll L.

Archives of Civil and Mechanical Engineering

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2018

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tom Vol. 18, no. 1

256--266

EN

The present work presents a comprehensive design and dynamic calculation of singular metallic structures, part of the Neutrino Experiment NEXT. The experiment uses an electroluminescent TPC chamber, a high-pressure 136Xe gas vessel enclosing the detector. A lead-block “castle” or containing box shields this vessel against external γ-rays from all directions; in spite of its heavy weight, the castle must be regularly open for the detector maintenance. Since the structures will be constructed at a middle-level seismic localization (Laboratorio Subterráneo Canfranc, Spain), the earthquake hazard must be taken into account. Vessel and castle are supported by a rigid frame, which must satisfy two requirements: (i) the Spanish seismic standard, (ii) for equipment protection, the detector maximum horizontal acceleration must be <1 [m/s2]. This frame rests on special base isolators to decrease horizontal accelerations in case of an earthquake. Three dynamical calculations are conducted: (i) a response spectrum analysis to comply with the standard, (ii) five time-history analyses to calculate tolerances and, (iii) a reliability-based approach using 1000 time-history responses to ensure satisfaction of the operating requirements. The final outcome is the design of a singular structure optimized for the NEXT experiment with a probability of failure against any standard earthquake of only 0.125%.