Ajibola I. Quadri
Abstract
Nowadays assessment of fatigue and reliability of structures have increased dramatically. This is confirmed by the recommendations of the standards and constitutive model of concrete in which the rules and requirements to ensure safety, serviceability and durability of the structure are stated. This ...
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Nowadays assessment of fatigue and reliability of structures have increased dramatically. This is confirmed by the recommendations of the standards and constitutive model of concrete in which the rules and requirements to ensure safety, serviceability and durability of the structure are stated. This study is directed to the reliability assessment of reinforced concrete column and fatigue comparison of (BS: 8110, 1997) and Eurocode 2 (EN: 2, 2004) ultimate limit state requirements on nominal eccentricity of short column resisting moments and forces. The column was modelled as one end fixed to resist moment reaction and free at the other end. It was then examined on fatigue and probabilistically assessed with the variables relating to the uncertainty loading conditions. The First-Order Reliability Method (FORM 5) encoded in CalREL was employed to estimate the implied probability of failure by varying load ratio and reinforcement ratio. And was verified with numerical simulation on CONCRETE MODEL OF 3 Dimension (COM 3). The results obtained have shown that the column assessed lost its flexural and shear carrying capacity gradually as the percentage load increased especially at the joint. Reinforced concrete column’s performance may be dependent on the applied load and could fail if it carries a lot more than the designed loads. It is therefore necessary to perform fatigue investigation to double check the resistant capacity of the column.
Structural Simulation
Sobhan Mosayebidorcheh; M. Mahmoodi; Taha Mosayebidorcheh; D. D. Ganji
Abstract
This article is aimed to introduce a new hybrid analytical-digital technique for solving a wide range of problems in fluid mechanics. This method is according to the Different Transform Method (DTM) and Newton’s Iterative Method (NIM). In the Boundary Value Problems (BVP), the system and the boundary ...
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This article is aimed to introduce a new hybrid analytical-digital technique for solving a wide range of problems in fluid mechanics. This method is according to the Different Transform Method (DTM) and Newton’s Iterative Method (NIM). In the Boundary Value Problems (BVP), the system and the boundary conditions converted to an algebraic equation set, and the Taylor series of the solution are subsequently calculated. By finding Jacobian matrix, the unknown parameters of the solution may be calculated using the multi-variable iterative Newton's method. The techniques are employed to determine a proximate solution for the problem. To expound upon the application of the new hybrid method illustratively, two nonlinear problems in fluid mechanics are considered: condensation film on the inclined rotating disk and the rotating MHD flow on a porous shrinking sheet. Using comparing the present results obtained with the numerical solutions and results presented in the literature, an excellent accuracy is observed. Quick convergence of the solution is another important merit of the proposed method.
Stochastic and Statistical Analysis of Structural Resistance and Material
Kolawole Abejide; Jubril Kaurra Mohammed; A. Lawan; Olugbenga Samuel Abejide
Abstract
This study presents the structural reliability of rolled steel beams on offshore platforms exposed to corrosion during their design period and beyond. The rate of corrosion of the rolled steel beam was determined using a standard expression for extreme marine environment. Limit equations were used to ...
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This study presents the structural reliability of rolled steel beams on offshore platforms exposed to corrosion during their design period and beyond. The rate of corrosion of the rolled steel beam was determined using a standard expression for extreme marine environment. Limit equations were used to evaluate the shear performance, deflection, and resistance moment of the rolled steel beams during their design period. The exposure to corrosion was evaluated using the First Order Reliability Method (FORM) in MATLAB with FERUM Version 4.0 (Finite Element Reliability Using Matlab). An increasing decline in the shear, resistance moment, and deflection was observed as the cross sectional area decreased due to corrosion, which is consistent with experimental data. However, it was also noted that the design formulation is robust enough to exceed the design life prediction in the code.
Failure Probability
Saran Srikanth Bodda; Abhinav Gupta; BuSeog Ju; Minho Kwon
Abstract
Safety of critical industrial facilities such as Nuclear power plants has gained significant attention against external events in the last decade. Fukushima Daiichi nuclear power station disaster occurred due to flooding of the plant which was caused by the Great East Japan earthquake and the subsequent ...
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Safety of critical industrial facilities such as Nuclear power plants has gained significant attention against external events in the last decade. Fukushima Daiichi nuclear power station disaster occurred due to flooding of the plant which was caused by the Great East Japan earthquake and the subsequent tsunami. In the US, failure of floodwall system during hurricane Katrina caused widespread damage. Floodwalls are essential to mitigate the effects of rising sea-levels due to climate change. Critical industrial facilities are being increasingly protected from the effects of floods through the use of flood protection systems such as floodwalls, dams, and weirs. This paper evaluates the fragilities for failure of a concrete floodwall due to various failure modes under a multi-hazard scenario (flooding and seismic events). Structural failure of the concrete floodwall is characterized by excessive deformation failure mode for seismic loads. The failure modes considered for flooding loads are rigid body failure and foundation failure.
Uncertainties Evaluation of Loads and Loading Conditions
Franziska Schmidt; Marcel Nowak; Mariia Nesterova; Oliver Fischer
Abstract
When dealing with the construction of a bridge or the assessment of an existing bridge to traffic loads, one important point is the prediction of reliability levels for critical details to the expected traffic loads in its remaining lifetime: this is done here for details of a steel-orthotropic bridge ...
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When dealing with the construction of a bridge or the assessment of an existing bridge to traffic loads, one important point is the prediction of reliability levels for critical details to the expected traffic loads in its remaining lifetime: this is done here for details of a steel-orthotropic bridge deck based on limited traffic monitoring data. A comparison of results from different statistical approaches is made by analyzing the recorded data for the traffic actions: to do that, the work begins with the writing of limit state functions for the ultimate limit state using various probability distributions, to evaluate the corresponding reliability indexes. Indeed, three methods to assess extreme values, Generalized Extreme Value, Peaks-over-Threshold and Level Crossing Counting, are applied. Therefore, one of the extrapolation methods that have been used in the background works for the European Norms (Eurocode 1) is treated here. Moreover, the comparison with the European design load model and the corresponding ultimate limit state is made.