Investigating Partial Factors for the Assessment of Existing Reinforced Concrete Bridges

Abstract

There is a great interest in developing an adequate partial factor format for the assessment of existing structures, and in particular bridges, which should be able to take various aspects into account linked to the fact that the structure already exists. As the structure is existing, additional information related to material parameters, loading conditions, local structural defects, etc. can be accounted for. In addition, the degree of conservatism needs to be well balanced to avoid unnecessary investment of resources in replacement or retrofitting. This contribution considers the experience gained these last years in parallel with some ongoing standardisation work in relation to the Eurocodes and the next edition of the fib Model Code for new and existing concrete structures. The current state of the art on partial factors for the assessment of existing structures is explored and the differences are assessed based on a comparison between (i) the use of recommended fixed partial factors as provided in many national and international codes (ii) adjusted (flexible) partial factors derived for the individual case under consideration; and (ii) a reliability-based verification. In order to assess the adequacy of proposals and identify some differences, the available partial factor formats are applied to two case studies of reinforced concrete bridges and critically assessed.

Experimental Investigation of the Explosion Effects on Reinforced Concrete Slabs with Fibers

“…Most modern infrastructures, such as bridges, power plants, and TV towers, are made of concrete and are exposed to various actions: earthquakes, climate change, aggressive environments, live load increases, wars, and terrorist threats [4,[12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Urban warfare has contributed to the increasing presence of explosive materials in populated areas.…”