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Abstract

The objective of these analyzes is to evaluate the behaviour of bearing cage in operation and to determinate the safety factor towards to yield and ultimate strength of structure, when cage is under load. Safety factor can be defined as force needed to achieve yield or ultimate strength divided by operation force given from dynamic simulation. Second analyze was based on pressing of whole cage in radial direction to determinate radial pressing force needed to achieve yield and ultimate strength.

student attitudes toward medical errors and adverse events. Jt Comm J Qual Patient Saf. 2007; 33:493-501. 44. Organization WH. Taxonomy. The Conceptual Framework for the International Classification for Patient Safety. Geneva; 2009. Available from: http://www.who.int/patientsafety/implementation/taxonomy/icps_technical_report_en.pdf; Access December 20, 2012. 45. Monroe K, Wang D, Vincent C, Woloshynowych M, Neale G, Inwald DP. Patient safety factors in children dying in a paediatric intensive care unit (PICU): a case notes review study. BMJ Qual Saf. 2011; 20: 863

Abstract

Currently, ferry services are widespread in Europe, the Baltic States, the CIS and they continue to progress rapidly despite the unstable global economy. An activity of modern cargo-and-passenger fleet is based on nevertheless the perspective of stable profit generation. In conditions of ferry market instability, the important task is to ensure the break-even analysis in operation of vessels and justification of relevant quantitative indicators. At the same time, when managing the production activity of the ferry operators and, in particular, when analysing the ferry operation the indicator of its financial safety factor is of great importance. This paper refines static indicators and determines dynamic indicators of critical quantity of cargoes and passengers in ferry loading; gives analytical method of its justification; develops analytical method and presents graphical method of financial safety factor estimation when loading of cargo only or boarding of passengers only, as well as performing composite actions - loading of cargoes and picking up passengers.

Abstract

The objective of the paper was to determine the level of circumferential stress in a wall of an open milk tank and to assess the tank wall degree of utilization according to the FKM Guideline calculation algorithm − Analytical Strength Assessment of Components, Made of Steel Cast Iron and Aluminium Materials in Mechanical Engineering. (German: FKM – Forschungskuratorium für Maschinenbau). The stress level in the tank wall was determined based on analytical calculations and numerical method using the FEA – Finite Elements Analysis. Numerical calculations were made in FEMAP with NX NASTRAN Solver (NASTRAN – NASA Structure Analysis). Similar stress values were found using two independent calculation methods. The difference between obtained stress values does not exceed 2%. Based on the FKM algorithm, the safety factor jges = 1.4 and static capacity of the tank wall ask = 19.7% were calculated.

Abstract

Anchored retaining walls are structures designed to support different loading applied in static and dynamic cases. The purpose of this work is to design and study the stability of an anchored retaining wall loaded with different seismic actions to obtain minimal anchor lengths. Mononobe-Okabe theory has been applied for the evaluation of seismic earth pressures developed behind the anchored wall. Checking the dynamic stability of anchored retaining walls is usually done using the classic Kranz model. To take into consideration the effects of the internal forces developed during failure, we have proposed a new model, based on the Kranz model, which will be used as the Kranz model to find the critical angle failure performed iteratively until the required horizontal anchor length is reached for a minimum safety factor. The results of this study confirm that the effect of the seismic load on the design of an anchored retaining wall, and its stability, has a considerable influence on the estimation of anchor lengths. To validate the modifications made to the new model, a numerical analysis was carried out using the Plaxis 2D software. The interpretation of the obtained results may provide more detailed explanation on the effect of seismic intensities for the design of anchored retaining walls.

Abstract

Cold-formed thin-walled sections are prone to local buckling caused by residual stresses, geometrical imperfections and inconsistency of material properties. We present a real case of buckling failure and conduct a numerical and experimental study aimed to identify methods capable of predicting such failures. It is important because designers of structures are getting more FEA-oriented and tend to avoid lengthy procedures of cold-formed structures design. Currently adopted methods are complicated and require patience and caution from a designer which is reasonable in case of the most important structural members but not necessarily so in ordinary design. Since it is important, we offer an insight into several FEA and manual methods which were sufficient to predict the failure while remaining fairly simple. Using a non-uniform partial safety factor was still necessary. We hope that this paper will be of interest for people performing a lot of routine analyses and worrying about reliability of their computations.

Abstract

The article compared the results of high cycle fatigue tests in samples of aluminum alloy 2024-T4, which is used in aircraft construction, especially for highly loaded structural elements, including for plating and fuselage frames and girders rotor blades of helicopters - with results available in the literature. The tests were performed on cylindrical samples, of a parallel and perpendicular orientation relative to the "direction of embodiment" or the rolling direction of the blank sheet metal with a coefficient of asymmetry cycle R = −1. Material for the study was collected from the production line design elements PZL-130 Orlik TC-II. There have been a description of the analytical results in the form of Morrow equations. The results were referred to the respective curves contained in a database of material U.S. Department of Transportation Federal Aviation Administration. There have been a presentation the transformation method of S-N curves for different stress ratio R, stress concentration factors Kt and safety factors βN and βσ.

Abstract

The European standard for the design of concrete structures that are likely to lose stability requires taking into account the effects of second order theory. This effect increases the impact of a bending moment due to member deformation and additional eccentricity. Slender members can be calculated by the use of a non-linear method. This approach shows a deficit in global reliability for cases where the concrete columns fail due to the loss of stability before reaching the design resistance in the critical cross-sections. Buckling is a brittle failure which occurs without any warning, and the probability of its formation is markedly influenced by the slenderness of the column. Here, the calculation results are presented and compared with the results from an experiment which was carried out in cooperation with STRABAG Bratislava LTD at the Central Laboratory of the Faculty of Civil Engineering SUT in Bratislava. The columns were designed according to the methods stated in STN EN 1992-1-1, namely, a general non-linear method. The focus of this study is to compare multiple approaches based on codes used in Germany (DIN 1045-1, 2001) and Austria (ÖNORM B 4700, 2001) with the present European code mentioned above. The paper aims to compare the global reliability of slender concrete columns with variable slendernesses of 90 and 160.

Abstract

An impoundment is an engineering construction used for the safe deposition of unexploitable waste from industrial and mining facilities. In terms of the legislative requirements of the Slovak Republic, a “Measurements Project” must be developed for each impoundment. In this document the prerequisites for the safe operation of an impoundment, the limit and critical values of the monitored phenomena and the facts influencing the safety of the impoundment and the area endangered by such a site are also defined. The safety and stability of an impoundment are verified according to a ”Measurements Project” by considering stability at regular time intervals. This contribution presents, in the form of a parametric study, a stability analysis of an ash impoundment. The stability analysis provides an example of the utilization of an information database of the results of the regular monitoring of the geotechnical properties of the materials forming the impoundment´s body and the surrounding rock mass. The stability of the impoundment is expressed for a recent state - without a continuous water level in its body and, at the same time, for a hypothetical limit and critical water level according to the valid “Handling Regulations“.

days. All the combinations of reshores for 10 levels of shore are undesirable with respect to safety. Similarly, 11S–1R also violates safety condition making the total cost very high. All other combinations of shore and reshore levels are having moderate cost with the desired safety factor. Fig. 3 Cost for different combinations of shore/reshore levels for a 20-storey building. The case of 1S–11R gives the optimum cost of 71,567.4 USD with a cycle time of 3 days for M40 concrete. All the combinations of shore and reshore levels maintain the FoS of 1.5 with the cycle