Use of reliability methods for evaluating safety of historic structures

Fort Stanwix National Monument, located in Rome, NY, is a historic park with a complex use history dating back to the early Colonial period and through the urban expansion and recent economic revitalization of the City of Rome. The goal of this study was to conduct a GPR investigation over an area approximately 1 acre in size to identify buried historic features (particularly buildings) so park management can preserve these resources and develop appropriate educational programming and management plans. The GPR recorded reflection events consistent with our expectations of historic structures. Differences in size, shape, orientation, and depth suggest that these responses likely date to different time periods in the site’s history. The GPR recorded other reflection anomalies that are difficult to interpret without any additional information, which suggests that pairing high-density geophysical data with limited excavations is critical to elaborate a complex site’s intricate history.

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Analysis of Human Error Risk with Human Reliability Methods in Construction Projects

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1003/1/012079 ◽

2020 ◽

Vol 1003 ◽

pp. 012079

Author(s):

M A Priska Sinabariba ◽

M R Ghifari ◽

E Muslim ◽

B N Moch

Keyword(s):

Construction Projects ◽

Human Error ◽

Human Reliability ◽

Reliability Methods ◽

Error Risk

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Effective Improvements to Reliability Based Corrosion Management

2010 8th International Pipeline Conference, Volume 4 ◽

10.1115/ipc2010-31425 ◽

2010 ◽

Cited By ~ 8

Author(s):

Shahani Kariyawasam ◽

Warren Peterson

Keyword(s):

Decision Making ◽

Oil And Gas ◽

Data Gathering ◽

Effective Area ◽

The Face ◽

Integrity Management ◽

Reliability Methods ◽

Specific Growth Rates ◽

Safe Condition ◽

Effective Use

Reliability methods have being adopted by oil and gas operators for integrity management decisions. These methods explicitly account for all relevant uncertainties and are designed to provide consistent safety. Consequently, a risk or reliability based approach is a very appropriate basis for decision making in the face of uncertainties. However, as in the effective use of any powerful methodology the sensitivities of the method to assumptions and limitations of applicability need to be well understood. This paper presents how improvements were made to reliability based integrity program by understanding its limitations and sensitivities. First the inputs that have the highest impact on the results were identified. These inputs are the most appropriate areas for improvement and data gathering. It is also very important to understand how the results are to be used and for what purpose. The results of this particular inline inspection based reliability assessment are used to make better excavation and repair decisions. A defect-based and joint-based decision making process is essential for determining with sufficient confidence if each defect and joint is in a safe condition. Consequently, the improvements are focused on discriminating between the myriad of defects found during an inline inspection run. Distinct field characteristics of corrosion growth are also taken into account in these improvements. The paper presents the implementation of effective area methods for future integrity probabilistic evaluations. It also describes the benefit of applying defect-specific growth rates. Finally, case studies are presented to demonstrate the effectiveness of the changes.

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A New Methodology for the Reliability Based Particle Swarm Optimization with Simulated Annealing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.274.101 ◽

2011 ◽

Vol 274 ◽

pp. 101-111 ◽

Cited By ~ 1

Author(s):

Norelislam Elhami ◽

Rachid Ellaia ◽

Mhamed Itmi

Keyword(s):

Particle Swarm Optimization ◽

Simulated Annealing ◽

Numerical Models ◽

Limit State ◽

Particle Swarm ◽

Geometrical Parameters ◽

Rectangular Plates ◽

Swarm Optimization ◽

Reliability Methods ◽

State Functions

This paper presents a new methodology for the Reliability Based Particle Swarm Optimization with Simulated Annealing. The reliability analysis procedure couple traditional and modified first and second order reliability methods, in rectangular plates modelled by an Assumed Modes approach. Both reliability methods are applicable to the implicit limit state functions through numerical models, like those based on the Assumed Mode Method. For traditional reliability approaches, the algorithms FORM and SORM use a Newton-Raphson procedure for estimate design point. In modified approaches, the algorithms are based on heuristic optimization methods such as Particle Swarm Optimization and Simulated Annealing Optimization. Numerical applications in static, dynamic and stability problems are used to illustrate the applicability and effectiveness of proposed methodology. These examples consist in a rectangular plates subjected to in-plane external loads, material and geometrical parameters which are considered as random variables. The results show that the predicted reliability levels are accurate to evaluate simultaneously various implicit limit state functions with respect to static, dynamic and stability criterions.

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