Task Group 1.3
Calibration of Partial Safety Factors for the Assessment of Existing Bridges Mission Statement/Objectives The mission of TG1.3 is to advance the field of structural engineering through the calibration of partial safety factors for the assessment of existing bridges. The TG aims to investigate how performance models, employing probabilistic approaches, are currently being employed by bridge owners/operators and furthermore can be developed by referencing physical models. Focus is placed on incorporating information obtained from inspection and monitoring strategies, and on designing optimal strategies in this context. The overarching objective is to provide guidance for the optimal assessment of existing bridges. Through this research, the TG seeks to utilize the safety, reliability , and longevity of built infrastructure, with particular focus on bridge structures, thereby contributing to the resilience and sustainability of transportation networks.
As indicated in the JRC report of CEN/TC250/WG2, 2015), “The application of design-orientated methods to the assessment of existing structures often leads to a high degree of conservatism. This conservatism has severe economic, environment and socio-political consequences when it results in satisfactory structures being condemned as unsafe, thereby leading to an unnecessary investment of resources in replacement or retrofitting, with its associated dismantling. The approach to the assessment of an existing structure is in many respects different from that in designing new structures. The effects of the construction process and subsequent life of the structure, during which it may have undergone alteration, deterioration, misuse and other changes to its as-built (as designed) state, need to be taken into account. It is thus possible to obtain and gain more or less detailed information on a specific structure. This is one of the fundamental differences with respect to the methodology used for the design of new structures where uncertainties are dealt with by relying on information gained from experience.” The partial safety approach considers the application of statistics and probability in the evaluation of the input data, the formulation of assessment criteria, and the determination of load and resistance factors. This approach allows easy calculations, while covering the variability in structural behaviour and loading. However, semi-probabilistic formats are not able to efficiency and correctly manipulate information obtained from measurements and inspections and their use for performance assessment of structures still represents a challenge. To overcome this limitation, a probabilistic approach will be considered to re-calibrate partial factors. The work of the TG is timely given the advent of the new Eurocode EN1990 Part 2 on the Assessment and Retrofit of Existing Structures which specifically refers to probabilistic assessment to validate the reliability of existing structures. The group will, as part of its new mandate, seek to engage with authorities to map the extent to which advanced approaches are applied and furthermore to identify how to overcome barriers to implementation. Expected Project Output
Start Date: May 2024
| Chair Alan O'Connor, Ireland
Talking about the aims of TG1.3 (Click Here) Vice Chair Joan Hee Roldsgaard, Denmark
Members André Orcesi, France Vazul Boros, Germany Robby Caspeele, Belgium Alaa Chateauneuf, France Dimitris Diamantidis, Germany Ana Mandić Ivanković, Croatia Roman Lenner, South Africa Heiki Lilja, Finland Maria Pina Limongelli, Italy Marija Kušter Maric, Croatia Jochen Köhler, Norway Nisrine Makhoul, Lebanon Jose Matos, Portugal Vitali Nadolski, Czech Republic Silja T. Nielsen, Denmark Fabrizio Palmisano, Italy Marco Proverbio, Singapore Franziska Schmidt, France Dominik Skokandić, Croatia Miroslav Sýkora, Czech Republic Pierre van der Spuy, South Africa Salvatore Dibernardo, USA |
