Indicative timetable of activities

Keynote lectures

Technical improvments mase in second generation of Eurocodes for steel and concrete bridges design Chris Hendy, AtkinsRéalis

The first generation Eurocodes became mandatory within EU and EFTA countries in March 2010, although voluntary take up started in many countries from around 2008. Work began almost immediately afterwards to pave the way for second generation Eurocodes. We now have availability of many of these second generation Eurocode parts, together with some completely new parts. Essentially, all Eurocodes will be available to National Standards Bodies by March 2026, who must then publish their National Annexes by March 2027 and the first generation Eurocodes will be withdrawn in March 2028.

The principal focus for the update has been to improve their ease of use, but inevitably many technical changes and additions have been made along the way. Essentially, these have been made where the existing rules are:

• not sufficiently safe (provisions which may have inadequate reliability)
• too safe (provisions which may have excessive reliability)
• inadequate to cover more recently available materials (such as fibre reinforced concrete or non-metallic reinforcements), construction types or modelling techniques
• unclear in their application.

This paper explores some of the key technical changes and additions made across steel and concrete bridge design and will highlight the reasons behind these changes and the benefits. 

Chris is Head of Bridge Engineering in AtkinsRéalis where he has led some of their most complex bridge projects.  In 2012 he was awarded the UK Royal Academy of Engineering Silver Medal and was elected a Fellow of the Royal Academy in 2013.  He was awarded the Institution of Civil Engineer’s Gold Medal in 2016.  He is Chairman of the BSI bridge committee, the UK’s Steel Bridge Group and fibUK.  He was a Project Team member for the second generation Eurocodes EN 1993-1-5, EN 1993-2 and EN 1993-1-11 which deal with plate buckling, steel bridge design and cable-supported structures respectively.

Actual trends in design, construction and monitoring of large-span bridges Marjan Pipenbaher, Ponting – Pipenbaher Consulting Engineers

Since the dawn of civilisation, bridges have played an important role in economic growth and the development of societies. Advances in the design and construction of bridges provide an insight into the progress of technology over time. In less than 2,000 years, we have evolved from ancient stone arches spanning just a few metres to modern bridges with cable-stayed cables spanning over 1,000 metres and suspension bridges over 2,000 metres long.
Advances in structural systems, high-strength and ultra-high-strength materials and high-performance computers are enabling the design of the most challenging structures of all time. Current trends in this field are focussed on the following main areas: the development of innovative structural systems, the development of high-strength materials, the aerodynamic stability of lightweight steel bridge structures and seismic safety.
In earthquake-prone areas, the design of bridges requires a comprehensive understanding of the interaction between the subsoil and the bridge structure. The use of seismic isolation systems to protect structural integrity, non-linear dynamic analyses, often in combination with time history simulations of earthquakes, provide information on the actual behaviour of structures during an earthquake.
Instabilities caused by fast gusts of wind are a major challenge in the construction of large span bridges today. Aerodynamic forces, air turbulence-induced vibrations, torsional flutter and sway can cause dangerous vibrations in road structures that affect safety, stability and durability. To overcome these challenges, modern bridge engineering focuses heavily on optimising the geometry of the cross-sections of road structures and other load-bearing elements. To this end, extensive CFD (computational fluid dynamics) analyses, FSI (fluid-structure interaction) analyses and, above all, extensive wind tunnel tests are carried out.

In the past, suspension bridges were often the only way to bridge large distances. In the last 30 years, however, cable-stayed bridges have become serious competitors to suspension bridges, even for spans over 1000 metres, mainly because of their greater stiffness and aerodynamic stability. Some of the most important examples of these bridges are the Russky Bridge (Russia) with a span of 1,104 metres, the Sutong Bridge (China) with a span of 1,088 metres and the Stonecutters Bridge (Hong Kong) with a span of 1,018 metres.

The further development of the design and construction of bridges with large spans is being driven by the development of new materials and modern and innovative designs. High and ultra-high strength concretes with more than 120 MPa, cables with a guaranteed tensile strength of steel cables of more than 2200 MPa and lightweight carbon fibre reinforced polymer (CFRP) cables with tensile strengths of more than 3300 MPa and a weight of only 1600 kg/m³ now enable the construction of bridges with spans of more than 3000 metres.

Using the latest computer tools, new materials and construction systems, engineers continue to push the boundaries of long-span bridge design and construction to ensure that the infrastructure of the future is safe, efficient and resilient.

Marjan Pipenbaher  is a director and partner at Ponting and founder and director of the specialised engineering firm Pipenbaher Consulting Engineers. In his more than 40-year career, he has designed and constructed more than 200 bridges and other complex engineering structures in Slovenia and abroad. These include the Črni Kal motorway viaduct and the Gabrovica and Vinjan railway viaducts on the second track of the Divača-Koper line, cable stayed Millennium Bridge in Montenegro, the cable stayed bridges Nissibi and Komurhan over the Euphrates in Turkey, the largest railway bridge in Israel, bridge No. 10 on the new high-speed railway line between Tel Aviv and Jerusalem, the Sur Oued Menar viaduct in Algeria and, a few years ago, the famous Croatian bridge on the Pelješac peninsula.

He is the author or co-author of over 200 professional and scientific articles that have been published in domestic and foreign specialised literature. For his professional and long-term pedagogical work at the Faculty of Civil Engineering, Transport and Architecture in Maribor, as well as for his scientific research activities, he has received numerous domestic and foreign awards and honours. Among others, he received the Gold Medal of the University of Maribor, the Puh Award for outstanding achievements in bridge design, the Kolos Award of the Croatian Chamber of Engineers, the Gustav Lindenthal Medal of the American Society of Civil Engineers for the successful construction of the Pelješac Bridge, the Award of the Slovenian Chamber of Engineers for outstanding achievements in engineering, the Golden Pencil Award of the Chamber of Architecture and the Plečnik Medal of the Plečnik Fund for the construction of the Štukelj Bridge in Novo Mesto. He also received a national award for his outstanding achievements in the design and construction of bridges – the Silver Order of Merit - and in 2022 the University of Maribor awarded him an honorary doctorate for his outstanding achievements in the field of bridge design.

Site-Specific Seismic Hazard Assessment for a Lava-Soil Stratigraphy Incorporating Near-Fault Effects Rajesh Rupakhety, University of Iceland

This keynote presents a site-specific seismic hazard study for a wind farm located in South Iceland. The site is underlain by volcanic sands interbedded with lava layers, a stratigraphy typical of regions affected by extensive volcanism. Site characterisation was conducted using ambient vibration measurements, resonant column tests, and downhole profiling. The influence of local geology on ground motion is captured through a period-dependent amplification function, AF(T), defined as the ratio of surface spectral acceleration (including non-linear site effects) to bedrock spectral acceleration.

The statistical properties of AF(T) are estimated through equivalent-linear analysis of the soil column, incorporating uncertainty in material properties. A probabilistic seismic hazard assessment (PSHA) is performed using Monte Carlo simulation of synthetic earthquake catalogues, which enables straightforward inclusion of site effects and facilitates handling of epistemic uncertainties. Instead of logic trees, a roulette sampling approach is used to alternate between candidate ground motion models.

Near-fault effects, which are especially relevant for long-period structures such as wind turbines, are incorporated deterministically. These are based on physics-based simulations of wave propagation from scenario earthquakes identified through hazard deaggregation. The resulting design ground motions and response spectra reflect a combined approach, integrating probabilistic hazard modelling with deterministic scenario analysis. Both aleatory and epistemic uncertainties are addressed within a unified framework.

Dr. Rajesh Rupakhety is a Professor of Earthquake Engineering and Vice-Head of the Faculty of Civil and Environmental Engineering at the University of Iceland. He is also Research Director of the Earthquake Engineering Research Centre and Chair of the Civil Engineering Department. Dr Rupakhety specialises in seismic hazard analysis, ground motion modelling, and earthquake-resistant design. His work integrates probabilistic and physics-based approaches for critical infrastructure. He earned his PhD from the University of Iceland and MSc from the ROSE School in Pavia, Italy.