A New Method of Reliability Analysis on Strength and Stiffness for Frame Structure

2010 ◽  
Vol 163-167 ◽  
pp. 3411-3414
Author(s):  
Yi Li ◽  
Bo Sun ◽  
Wen Zhao
Keyword(s):  
Reliability Analysis ◽  
Failure Modes ◽  
Recurrence Formula ◽  
Frame Structure ◽  
State Function ◽  
Matrix Operation ◽  
Variational Structure ◽  
Strength And Stiffness ◽  
Global Stiffness Matrix ◽  
New Criterion

An accelerating calculation of reliability analysis on strength and stiffness for frame structure was derived. The method of numerical analysis was combined with recurrence formula, to generatelimit state function of continual variational structure. This methodcan simplify the algorithm for identifying systemic dominant failure modes, because the repeated assembly of global stiffness matrix and repeated inverse matrix operation in analysis are avoided. A new criterion of degenerating the structure into mechanism is introduced. Continual analysis of variational structure can be realized.

scholarly journals Probabilistic Approach to System Reliability of Mechanism with Correlated Failure Models

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Xianzhen Huang ◽  
Yimin Zhang
Keyword(s):  
Reliability Analysis ◽  
System Reliability ◽  
Failure Modes ◽  
Limit State ◽  
Probabilistic Approach ◽  
Upper And Lower Bounds ◽  
State Function ◽  
System Reliability Analysis ◽  
Kinematic Performance ◽  
Planar Linkages

In this paper, based on the kinematic accuracy theory and matrix-based system reliability analysis method, a practical method for system reliability analysis of the kinematic performance of planar linkages with correlated failure modes is proposed. The Taylor series expansion is utilized to derive a general expression of the kinematic performance errors caused by random variables. A proper limit state function (performance function) for reliability analysis of the kinematic performance of planar linkages is established. Through the reliability theory and the linear programming method the upper and lower bounds of the system reliability of planar linkages are provided. In the course of system reliability analysis, the correlation of different failure modes is considered. Finally, the practicality, efficiency, and accuracy of the proposed method are shown by a numerical example.

The Application of Artificial BP Neural Networks and Monte-Carlo Method for the Reliability Analysis on Frame Structure

2012 ◽  
Vol 204-208 ◽  
pp. 3256-3259 ◽  
Author(s):  
Zhi Cheng Xue ◽  
Hai Jun Wang
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Reliability Analysis ◽  
Limit State ◽  
Frame Structure ◽  
State Function ◽  
Range Data ◽  
Limit State Function ◽  
The Monte Carlo Method ◽  
Wide Range

In order to conduct the reliability analysis of frame structure, the limit state function was first fitted by artificial BP neural network. Then considering the orthogonal array method, sample data was arranged. After that an improved network modes was trained for the probabilistic analysis on a wide range data with the Monte-Carlo method. The mean and standard deviation for the limit state function was easily obtained and the reliability index on the structure can be also calculated. Finally, the example indicated that this method used in the reliability analysis for frame structure was feasible.

Dynamic Response and Fatigue Reliability Analysis of Marine Riser Under Random Loads

2007 ◽  
Author(s):  
Rizwan A. Khan ◽  
Suhail Ahmad
Keyword(s):  
Reliability Analysis ◽  
Failure Modes ◽  
Oil Field ◽  
Environmental Damage ◽  
State Function ◽  
Unstable Fracture ◽  
Random Waves ◽  
Fatigue Reliability ◽  
Marine Riser ◽  
Reliability Method

Marine riser is a major component of offshore drilling and productions systems that are either fixed or floating. Since, a marine riser is intended to remain in station for the productive life of an oil field; it will be exposed to wide variety of hazards, with the potential for environmental damage, structural failure or damage to the material. As part of the design process, there are requirements of structural strength based on criteria referring to failure modes, such as rupture by over loading, fatigue failures, buckling or unstable fracture. 3D Nonlinear dynamic analysis of riser is carried out in the time domain using finite element solver ABAQUS/Aqua. The response histories so obtained are employed for the study of fatigue and fracture reliability analysis of riser under random waves and random waves together-with vessel motion. In the present study application of structural concepts for the evaluation of the fatigue resistance of marine risers, including reliability techniques has been presented. The limit state function has been established for cumulative fatigue damage using S-N curve approach and fracture mechanics approaches considering number of parameters, random in nature. Reliability methods deal with the uncertain nature of loads, resistance etc. and lead to prediction of the failure and a rational measure of the safety coefficient. Response surface method (RSM) in conjunction with First Order Reliability Method (FORM) has been used for reliability estimation. The results are compared with Monte Carlo simulation method. The design point important for the probabilistic design is located on the failure surface. The effects of the uncertainties in various random variables on riser fatigue reliability are highlighted.

System Reliability Analysis for Planar Mechanisms Using the Matrix Method

2012 ◽  
Vol 452-453 ◽  
pp. 1190-1194
Author(s):  
Xian Zhen Huang ◽  
Yi Min Zhang
Keyword(s):  
Reliability Analysis ◽  
System Reliability ◽  
Failure Modes ◽  
Limit State ◽  
Taylor Series Expansion ◽  
Upper And Lower Bounds ◽  
State Function ◽  
Planar Mechanisms ◽  
Kinematic Performance ◽  
Planar Linkages

In this paper, a practical technique for system reliability evaluation of kinematic performance of planar linkages with correlated failure modes is proposed. Taylor series expansion is utilized to derive a general expression of the kinematic performance errors caused by random design variables. A practical limit state function for reliability analysis of the kinematic performance of planar linkages corresponding to different failure models is established. Through the reliability theory and the linear programming method the upper and lower bounds of the system reliability of planar mechanisms are provided.

scholarly journals Time-Dependent Reliability Analysis of Reinforced Concrete Beams Subjected to Uniform and Pitting Corrosion and Brittle Fracture

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1820
Author(s):  
Mohamed El Amine Ben Seghier ◽  
Behrooz Keshtegar ◽  
Hussam Mahmoud
Keyword(s):  
Reinforced Concrete ◽  
Brittle Fracture ◽  
Reliability Analysis ◽  
Pitting Corrosion ◽  
Structural Reliability ◽  
Time Dependent ◽  
State Function ◽  
Rc Beams ◽  
Highly Nonlinear ◽  
Reliability Method

Reinforced concrete (RC) beams are basic elements used in the construction of various structures and infrastructural systems. When exposed to harsh environmental conditions, the integrity of RC beams could be compromised as a result of various deterioration mechanisms. One of the most common deterioration mechanisms is the formation of different types of corrosion in the steel reinforcements of the beams, which could impact the overall reliability of the beam. Existing classical reliability analysis methods have shown unstable results when used for the assessment of highly nonlinear problems, such as corroded RC beams. To that end, the main purpose of this paper is to explore the use of a structural reliability method for the multi-state assessment of corroded RC beams. To do so, an improved reliability method, namely the three-term conjugate map (TCM) based on the first order reliability method (FORM), is used. The application of the TCM method to identify the multi-state failure of RC beams is validated against various well-known structural reliability-based FORM formulations. The limit state function (LSF) for corroded RC beams is formulated in accordance with two corrosion types, namely uniform and pitting corrosion, and with consideration of brittle fracture due to the pit-to-crack transition probability. The time-dependent reliability analyses conducted in this study are also used to assess the influence of various parameters on the resulting failure probability of the corroded beams. The results show that the nominal bar diameter, corrosion initiation rate, and the external loads have an important influence on the safety of these structures. In addition, the proposed method is shown to outperform other reliability-based FORM formulations in predicting the level of reliability in RC beams.

Dynamic reliability analysis of mechanical system with wear and vibration failure modes

2021 ◽  
Vol 163 ◽  
pp. 104385
Author(s):  
We Wang ◽  
Gang Shen ◽  
Yimin Zhang ◽  
Zhencai Zhu ◽  
Changyou Li ◽  
...  
Keyword(s):  
Mechanical System ◽  
Reliability Analysis ◽  
Failure Modes ◽  
Dynamic Reliability

Reliability Analysis of Embankment Slope in Yaan-Luku Expressway

2011 ◽  
Vol 71-78 ◽  
pp. 1360-1365
Author(s):  
Jian Quan Ma ◽  
Guang Jie Li ◽  
Shi Bo Li ◽  
Pei Hua Xu
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Reliability Analysis ◽  
Failure Probability ◽  
Latin Hypercube Sampling ◽  
Natural State ◽  
State Function ◽  
Embankment Slope ◽  
The Times ◽  
Distribution Type

Take a typical cross-section of rockfill embankment slope in Yaan-Luku highway as the research object, reliability analysis is studied under the condition of water table of 840.85m, 851.50m, and loading condition of natural state and horizontal seismic acceleration of 0.2g, respectively. Raw data use Kolmogorov-Smirnov test (K-S test) to determine the distribution type of parametric variation. And the parameters were sampling with Latin hypercube sampling (LHS) method and Monte Carlo (MC) method, respectively, to obtain state function and determine safety factors and reliability indexes. A conclusion is drawn that the times of simulation based on LHS method were less than Monte Carlo method. Also the convergence of failure probability is better than the Monte Carlo method. The safety factor is greater than one and the failure probability has reached to 35.45% in condition of earthquake, which indicating that the instability of rockfill embankment slope is still possible.

Effects of infill patterns on the strength and stiffness of 3D printed topologically optimized geometries

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nadim S. Hmeidat ◽  
Bailey Brown ◽  
Xiu Jia ◽  
Natasha Vermaak ◽  
Brett Compton
Keyword(s):  
Material Properties ◽  
Failure Modes ◽  
Mechanical Anisotropy ◽  
Failure Behavior ◽  
Fused Filament Fabrication ◽  
Content Type ◽  
Orthotropic Composite ◽  
Material Extrusion ◽  
Specific Material ◽  
Strength And Stiffness

Purpose Mechanical anisotropy associated with material extrusion additive manufacturing (AM) complicates the design of complex structures. This study aims to focus on investigating the effects of design choices offered by material extrusion AM – namely, the choice of infill pattern – on the structural performance and optimality of a given optimized topology. Elucidation of these effects provides evidence that using design tools that incorporate anisotropic behavior is necessary for designing truly optimal structures for manufacturing via AM. Design/methodology/approach A benchmark topology optimization (TO) problem was solved for compliance minimization of a thick beam in three-point bending and the resulting geometry was printed using fused filament fabrication. The optimized geometry was printed using a variety of infill patterns and the strength, stiffness and failure behavior were analyzed and compared. The bending tests were accompanied by corresponding elastic finite element analyzes (FEA) in ABAQUS. The FEA used the material properties obtained during tensile and shear testing to define orthotropic composite plies and simulate individual printed layers in the physical specimens. Findings Experiments showed that stiffness varied by as much as 22% and failure load varied by as much as 426% between structures printed with different infill patterns. The observed failure modes were also highly dependent on infill patterns with failure propagating along with printed interfaces for all infill patterns that were consistent between layers. Elastic FEA using orthotropic composite plies was found to accurately predict the stiffness of printed structures, but a simple maximum stress failure criterion was not sufficient to predict strength. Despite this, FE stress contours proved beneficial in identifying the locations of failure in printed structures. Originality/value This study quantifies the effects of infill patterns in printed structures using a classic TO geometry. The results presented to establish a benchmark that can be used to guide the development of emerging manufacturing-oriented TO protocols that incorporate directionally-dependent, process-specific material properties.

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