German Proposals for the Revision of Eurocode 7 “Geotechnical design”

After implementing the Eurocodes, concerns were raised that the set of rules and regulations is not suitable for the designer’s day-to-day use. The first generation of Eurocodes consists of 58 codes with more than 5,200 pages. Moreover, practitioners have to cope with national supplementary codes. As a result, an “Initiative on Improving the Practicability of Technical Rules for Building Constructions” (PRB) was established by the German construction industry and associations of structural engineers in 2011. As part of the initiative, a Project Group for Geotechnical Design was established alongside groups for the other Eurocodes, with the aim of streamlining Eurocode 7 and reducing the number of design approaches and partial safety factors. The paper will analyse the shortcomings of the two parts of Eurocode 7 and present a concept for a more concise and user-friendly code. Furthermore, comparative calculations have been performed for standard geotechnical design applications to investigate the potential for European harmonization in geotechnical design. The results are described and it is shown how they can be incorporated in the revision of EC 7. Moreover, a new formula for verifying geotechnical ultimate limit states is presented which formally covers all design approaches and also enables other parameters such as consequence classes, human error etc. to be incorporated by applying different multiplicative partial safety factors.

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Safety factors and limit states analysis in geotechnical engineering

Canadian Geotechnical Journal ◽

10.1139/t84-001 ◽

1984 ◽

Vol 21 (1) ◽

pp. 1-7 ◽

Cited By ~ 15

Author(s):

G. G. Meyerhof

Keyword(s):

Geotechnical Engineering ◽

Stability Conditions ◽

Safety Factors ◽

Limit States ◽

Resistance Factors ◽

Performance Factors ◽

Load Factors ◽

Partial Safety Factors ◽

And Performance ◽

Earth Retaining Structures

This paper outlines the ultimate and serviceability limit states in geotechnical engineering analyses. The magnitude of customary total and suggested partial safety factors in earthworks, earth retaining structures, excavations, and foundations is discussed. On the basis of comparisons between these safety factors and using recommended load factors on various types of loading, including water pressures, common resistance factors on cohesion and friction of soils and performance factors can be established together with some additional modification factors for particular stability conditions. The serviceability limit states of foundations and structures are briefly discussed.

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Verification of ultimate limit states in geotechnical design by Eurocode 7 in France and Germany

Revue européenne de génie civil ◽

10.1080/17747120.2007.9692948 ◽

2007 ◽

Vol 11 (5) ◽

pp. 621-641 ◽

Cited By ~ 3

Author(s):

Roger Frank ◽

Bernd Schuppener ◽

Norbert Vogt ◽

Anton Weissenbach

Keyword(s):

Limit States ◽

Eurocode 7 ◽

Geotechnical Design ◽

Ultimate Limit

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Modified, Reliability-Based Robust Geotechnical Design Method, in Accordance with Eurocode 7

Applied Sciences ◽

10.3390/app11188423 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8423

Author(s):

Filip Dodigović ◽

Krešo Ivandić ◽

Meho-Saša Kovačević ◽

Božo Soldo

Keyword(s):

Reliability Index ◽

Design Method ◽

System Response ◽

Reliability Based Design ◽

Eurocode 7 ◽

Robustness Measure ◽

Response Variance ◽

Feasibility Robustness ◽

Geotechnical Design ◽

User Friendly

In this paper a modification of the reliability-based robust geotechnical design (RGD) method is proposed. The intention of the proposed modifications is to simplify the method, make it less computationally expensive, and harmonise of the results with Eurocode 7. The complexity of the RGD method mainly stems from the calculation of the design’s robustness measure, which is the feasibility robustness index (ββ). Due to this fact, the replacing of the existing robustness measure with a generalised reliability index (β) is considered. It was demonstrated that β fits into the robustness concept, and is traditionally used as a construction reliability measure, making it intuitive and “user friendly”. It is proposed to conduct a sensitivity analysis using Soboli indices, with the aim of freezing the variables whose contribution to the system response variance is negligible, which will further simplify the method. By changing the robustness measure, the number of the required reliability analyses is significantly decreased. Further reduction is achieved by conducting analyses only for the designs chosen in the scope of the genetic algorithm. The original RGD method is used as an extension of traditional reliability-based design. By applying the proposed modifications, the RGD method can be used as an alternative to the classic and reliability-based design method.

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Overturning Reliability Analysis of Jack-Up Platforms Using Spreadsheet

Volume 2A: Structures, Safety and Reliability ◽

10.1115/omae2013-10039 ◽

2013 ◽

Author(s):

Sirous F. Yasseri ◽

R. B. Mahani

Keyword(s):

Reliability Analysis ◽

Conditional Probabilities ◽

Safety Factors ◽

Limit States ◽

Environmental Loading ◽

Environmental Loads ◽

Structural Engineers ◽

Jack Up

In designing jack-ups to resist environmental loading, decisions are made under a great deal of uncertainty that may lead to a finite risk of exceeding limit states of the structures. In order to minimize the risks, conventional safety factors based on deterministic analyses, are commonly used. This paper present a simple spreadsheet based reliability analysis for assessing the safety of independent leg jack up platforms subjected to the overturning effect of environmental loads. The intention is to develop and illustrate procedures that can be used by structural engineers to assign conditional probabilities of failure to jack ups as a function of environmental loads.

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Verification of ultimate limit states in geotechnical design by Eurocode 7 in France and Germany

Revue européenne de génie civil ◽

10.3166/regc.11.621-642 ◽

2007 ◽

Vol 11 (5) ◽

pp. 621-642

Author(s):

Roger Franck ◽

Bernd Schuppener ◽

Norbert Vogt ◽

Anton Weissenbach

Keyword(s):

Limit States ◽

Eurocode 7 ◽

Geotechnical Design ◽

Ultimate Limit

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Limit states and reliability-based design for a non-codified problem of aqueduct buoyancy

Canadian Geotechnical Journal ◽

10.1139/t06-046 ◽

2006 ◽

Vol 43 (8) ◽

pp. 869-883

Author(s):

Gil Robinson ◽

James Graham ◽

Ken Skaftfeld ◽

Ron Sorokowski

Keyword(s):

Design Methods ◽

Model Parameters ◽

Safety Factors ◽

Design Code ◽

Limit States ◽

Reliability Based Design ◽

Simulation Techniques ◽

Working Stress ◽

Engineering Problems ◽

Partial Safety Factors

Limit states design methods and engineering judgement have been used to assess buoyancy issues for remediation of the 85 year old Shoal Lake Aqueduct in Manitoba. The study demonstrates how these methods can be applied to non-codified engineering problems. Four separate buoyancy analyses were completed using (i) partial safety factors from the Ontario Highway Bridge Design Code, (ii) project-specific partial safety factors, (iii) Monte Carlo simulation techniques, and (iv) working stress design (WSD) methods. Engineering judgement was required to develop a buoyancy model, interpret data for modeling parameters, and provide meaningful values for parameters that could not be measured. Results from the analyses show that more uniform reliability is provided when measured variability of the model parameters is accounted for. The reliability is not quantifiable when working stress design methods are used. Key words: limit states, probability, non-codified problem, aqueduct, buoyancy.

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A Reliability-Based Approach for the Design of Nuclear Piping for Internal Pressure

Journal of Pressure Vessel Technology ◽

10.1115/1.3122017 ◽

2009 ◽

Vol 131 (4) ◽

Cited By ~ 11

Author(s):

Kleio Avrithi ◽

Bilal M. Ayyub

Keyword(s):

Internal Pressure ◽

Allowable Stress ◽

Safety Factors ◽

Limit States ◽

Present Design ◽

Partial Safety Factors ◽

Factor Design ◽

American Society ◽

Load And Resistance Factor ◽

Allowable Stress Design

Nuclear pipes are designed to withstand primary membrane stresses generated by internal pressure according to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code, Section III, Parts NB-3641, NC-3641, and ND-3641, which uses the allowable stress design (ASD) method. This paper presents limit states and equations for the design of nuclear pipes for internal pressure based on the load and resistance factor design (LRFD) method. The LRFD method is shown and explained to be more consistent than the ASD method. The paper presents the procedure for the derivation of the partial safety factors. Moreover, these factors are evaluated, example calculations are provided, and comparisons with the present design are made.

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