Systematic derivation of safety factors for the fatigue design of steel bridges

This paper presents a probabilistic framework to derive the safety factors for fatigue of steel and composite steel concrete road bridges. Engineering models are used for the design and the safety factor is derived in such a way that the design meets the target reliability set by international Eurocode and ISO standards, estimated using measured...

Standardisation in Monitoring, Safety Assessment and Maintenance of the Transport Infrastructure: Current Status and Future Perspectives

This contribution is outlining the vision and approach developed in the IM-SAFE project towards the standardisation of monitoring, data-informed safety assessment and predictive maintenance policies of bridges and tunnels considering the integration of digital innovations and reports on the initial activity in the IM-SAFE project [1] that is...

Fatigue resistance of steel ropes: failure criterion. Background to the verification in prEN 1993-1-11:2020

Many steel rope systems are subjected to fluctuating tensile loads and therefore can fail due to fatigue. Available fatigue test data indicate that rope diameter, mean stress, socket type, lay angle and rope length influence the fatigue resistance. Most of the tests were terminated before full failure of the ropes. This paper shows that the test...

Calibrating partial factors - methodology, input data and case study of steel structures

Partial factors are commonly based on expert judgements and on calibration to previous design formats. This inevitably results in unbalanced structural reliability for different types of construction materials, loads and limit states. Probabilistic calibration makes it possible to account for plentiful requirements on structural performance,...

Fatigue design of tension components. Revision and further development of EN 1993-1-11

During the ongoing revision of EN 1993-1-11 “Design of structures with tension components” the

Revision of EN 1993-1-11 - fatigue design rules for tension components

As part of the ongoing revision of EN 1993-1-11 “Design of structures with tension components”, the current fatigue design rules have been subjected to a critical review. This has resulted in modifications and amendments, including the adjustment of several parameters. This paper provides an introduction to as well as background information on...

Reliability levels obtained by Eurocode partial factor design - A discussion on current and future reliability levels

To assess the reliability of a structure, reliability based codes such as EN1990:2002 allow for the application of full-probabilistic methods and semi-probabilistic methods (i.e. the partial factor method). In principle, both methods should be equivalent and lead to (approximately) the same reliability level. In this study, this equivalence is...

The design value method and adjusted partial factor approach for existing structures

In contrast to the design of new structures, the assessment of existing structures often relies on the subjective judgement of the investigating engineer. An objective verification format for existing structures based on alternative partial factors is however feasible, enabling a rather simple and straightforward, but objective and coherent...

The use of Eurocode EN 1991-1-4 procedures 1 and 2 for building dynamics, a comparative study

The design of tall buildings has to ensure adequate reliability but it also has to ensure that people in the building feel comfortable particularly when subject to wind-induced vibrations. Fulfilling vibration criteria for human comfort is often decisive in the structural design of flexible tall buildings. The new Eurocode EN 1991-1-4 provides...

Safety assessment of existing concrete slab bridges for shear capacity

Evaluating and upgrading concrete slab bridges is an important issue. A large part of the existing infrastructure has been built about 50 years ago and the design life has been reached or will be reached in the near future. Also traffic loads have increased significantly over the last 50 years. These structures need to be reassessed in order to...

Safety philosophy for existing structures and partial factors for traffic loads on bridges

Evaluating and upgrading existing structures becomes more and more important. For a large part of the existing infrastructure and buildings the design life has been reached or will be reached in the near future. These structures need to be reassessed in order to find out whether the safety requirements are met. Not only for new structures but...

Fatigue experiments on very high strength steel base material and transverse butt welds

Very High Strength Steels (VHSS) with nominal strengths up to 1100 MPa have been available on the market for many years. However, the use of these steels in the civil engineering industry is still uncommon, due to lack of design and fabrication knowledge and therefore limited inclusion in codes. Moreover, in a fatigue loaded VHSS structure...

Fatigue experiments on hybrid welded connections made of very high strength steels

In a fatigue loaded structure made of Very High Strength Steels (VHSS) absolute and relative stress variations will be higher compared to those in structures made of lower grade steels. Stress concentrations in joints reduce the advantage of VHSS under cyclic loading. A hybrid connection, consisting of cast steel welded to a VHSS member, could...

Dynamics of tall buildings under stochastic wind load: Applicability of Eurocode EN 1991-1-4 procedures 1 and 2

The new generation of tall buildings is higher and more slender than the buildings built before. Additionally, increased use is made of high-strength materials which have a higher strength yet the same stiffness properties as conventional materials. Both aspects increase the sensitivity of tall buildings to dynamic behaviour. The design has to...

Eurocodes and the structural safety of existing buildings - Considering the publication of the Dutch NEN 8700

Since 1992 there have been a number of proposals to renew calculation methods available to assess the structural safety of existing buildings. But without operational results. Upon publication of the Eurocodes NL decided to renew and to include them in the Dutch building regulations. The question was how. One decided to develop a new Dutch...

Storage tanks under earthquake loading, a case study. Evaluation of Eurocode 8 predictions

The behaviour under earthquake loading of an LNG (liquefied natura) gas)-tank with a diameter of 75 meters and a height of 32 meters has been studied analytically and numerically. Design rules for achieving a safe design, provided by Eurocode 8 'Design of structures for earthquake resistance - Part 4 : silos, tanks and pipelines' (ENV 1998-4)...