Influence of Concrete Strength Fractile Estimation on the Safety Level of Existing Structures Assessed Using the Adjusted Partial Factor Method

This paper is aimed at the reliability analysis of an existing reinforced concrete bridge from 1908. The load bearing capacity is assessed in accordance with valid standards using the partial factor method and probabilistic approach. Load bearing capacities obtained by these methods are critically compared. The application of probabilistic method leads to 40 % higher load bearing capacity then the partial factor method used for structural design.

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Fully probabilistic design: the way for optimizing of concrete structures

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952011000200002 ◽

2011 ◽

Vol 4 (2) ◽

pp. 173-177

Author(s):

I. Laníková ◽

P. Štěpánek ◽

P. Šimunek ◽

D. Horák ◽

M. Zlámal

Keyword(s):

Probabilistic Approach ◽

Concrete Structures ◽

Latin Hypercube Sampling ◽

Probabilistic Design ◽

Efficient Design ◽

Limit States ◽

Reliability Factor ◽

Factor Method ◽

Partial Factor Method ◽

Partial Factor

Some standards for the design of concrete structures (e.g. EC2 and the original ČSN 73 1201-86) allow a structure to be designed by several methods. This contribution documents the fact that even if a structure does not comply with the partial reliability factor method, according to EC2, it can satisfy the conditions during the application of the fully probabilistic approach when using the same standard. From an example of the reliability of a prestressed spun concrete pole designed by the partial factor method and fully probabilistic approach according to the Eurocode it is evident that an expert should apply a more precise (though unfortunately more complicated) method in the limiting cases. The Monte Carlo method, modified by the Latin Hypercube Sampling (LHS) method, has been used for the calculation of reliability. Ultimate and serviceability limit states were checked for the partial factor method and fully probabilistic design. As a result of fully probabilistic design it is possible to obtain a more efficient design for a structure.

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Adaptive Estimation of the In Situ Characteristic Concrete Strength

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.292.257 ◽

2019 ◽

Vol 292 ◽

pp. 257-263

Author(s):

Stanislav S. Derechennik ◽

Viktar V. Tur

Keyword(s):

Confidence Level ◽

Adaptive Estimation ◽

Concrete Strength ◽

Test Results ◽

Limited Sample ◽

Limited Sample Size ◽

Existing Structures ◽

Main Representative ◽

Partial Factor

For calculation of existing concrete structures on the basis of the partial factor format, the main representative value is the actual in-situ characteristic value of the concrete strength. When samples are tested, the concrete in-situ strength of the structure shall be determined, statistically if possible, from the test results. In accordance with EN 1990 the 5% percentile value is calculated on the basis of a unilaterally limited constant confidence level. It was found the in some case, estimation of the in-situ characteristic concrete strength taking a constant confidence level does not allow to adequately assess the reliability of the existing structures. A new estimator based on non-parametric statistical method was proposed for estimating of the in-situ characteristic concrete strength with a given arbitrary confidence level. The procedure that was proposed allows one to re-establish of the estimator pdf even with a very limited sample size. It is established, that the choice of the confidence level of the estimator should be based on the average reliability of the structure.

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On the applicability of the Eurocode 7 partial factor method for rock mechanics

Rock Engineering and Rock Mechanics: Structures in and on Rock Masses ◽

10.1201/b16955-264 ◽

2014 ◽

pp. 1517-1523 ◽

Cited By ~ 2

Author(s):

A Bedi ◽

T Orr

Keyword(s):

Rock Mechanics ◽

Factor Method ◽

Eurocode 7 ◽

Partial Factor Method ◽

Partial Factor

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An adjusted partial factor method for temporary structures compatible with the Eurocode framework

Civil Engineering and Environmental Systems ◽

10.1080/10286608.2012.733375 ◽

2013 ◽

Vol 30 (2) ◽

pp. 97-114 ◽

Cited By ~ 5

Author(s):

Robby C.E. Caspeele ◽

Raphaël D.J.M. Steenbergen ◽

Luc R. Taerwe

Keyword(s):

Factor Method ◽

Partial Factor Method ◽

Partial Factor

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Chapter 6 Verification by the partial factor method

Designers' Guide to EN 1990 Eurocode: Basis of Structural Design ◽

10.1680/dgte.30114.0007 ◽

2002 ◽

pp. 71-87

Keyword(s):

Factor Method ◽

Partial Factor Method ◽

Partial Factor

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Comparison of reliability evaluation methods between China and Canada standards for wood structures featuring duration of load

Journal of Wood Science ◽

10.1186/s10086-020-01920-0 ◽

2020 ◽

Vol 66 (1) ◽

Author(s):

Qiongyao Wu ◽

Shuang Niu ◽

Enchun Zhu

Keyword(s):

Reliability Analysis ◽

Analysis Method ◽

Safety Level ◽

Wood Structures ◽

Load Effect ◽

Key Factor ◽

Live Loads ◽

High Level ◽

Partial Factor ◽

Duration Of Load

Abstract Duration of load (DOL) is a key factor in design of wood structures, which makes the reliability analysis of wood structures more complicated. The importance of DOL is widely recognized, yet the methods and models through which it is incorporated into design codes vary substantially by country/region. Few investigations of the effect of different model assumptions of DOL and other random variables on the results of reliability analysis of wood structures can be found. In this paper, comparisons are made on the reliability analysis methods that underlie the China and the Canada standards for design of wood structures. Main characteristics of these two methods, especially the way how DOL is treated are investigated. Reliability analysis was carried out with the two methods employing the same set of material properties and load parameters. The resulted relationships between reliability index β and resistance partial factor γR* (the β–γR* curves) for four load combinations are compared to study the safety level indicated by the two methods. The comparison shows that the damage accumulation model (Foschi–Yao model) in the Canada analysis method is highly dependent on the type and duration of load, resulting in more conservative design than the China analysis method in loading cases dominated by dead load, but less conservative design in cases of high level of live loads. The characteristics of the load effect term of the performance function are also found to make considerable difference in reliability levels between the two methods. This study aims to provide references for researchers and standard developers in the field of wood structures.

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