Reliability assessment of heritage structures is in many aspects different from structural design. The effects of the construction process and subsequent life of the architecture, during which it may have undergone alteration, deterioration or misuse must be taken into account. That is why the assessment of heritage architecture often requires application of sophisticated methods, as a rule beyond the scope of design codes. The two main principles for the assessment may be summarized as follows: (1) Available scientific knowledge and experience including currently valid codes should be applied; (2) Actual characteristics of structural materials, actions, geometric data and structural behaviour should be considered. The most important step of the whole assessment may be evaluation of inspection data.

The fib Model Code offers pre-normative guidance based on the synthesis of international research, industry and engineering expertise. Its new edition (draft MC 2020) will bring together coherent knowledge and experience for both the design of new concrete structures and the assessment of existing concrete structures. This contribution presents an overview of the main developments related to the partial factors for materials. In the draft MC2020, the partial factors are presented in tables for clusters of cases depending on consequence classes and variability of basic variables. Furthermore, formulas and background information are provided to facilitate updating of the partial factors. This contribution discusses the different assumptions adopted in MC 2020 for design and assessment. Main changes with respect to the previous version are related to description of the difference between in-situ concrete strength and the material strength measured on control specimens, and to modelling of geometrical variables. The presented comparison of the requirements imposed by Eurocodes and MC 2020 for design reveals insignificant differences. The assessment requirements may be decreased by about 25% when the conditions specified in MC 2020 are satisfied. Hence, the revised MC 2020 will provide designers and code makers with wider possibilities to utilise actual data and long-term experience in assessments of existing structures.

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Selected standardised models for the verification of punching shear in reinforced concrete structures are applied for the probabilistic assessment of their reliability level. It appears that the models given in EN 1992-1-1 and prEN 1992-1-1 lead to more realistic estimates of the reliability level of existing reinforced concrete members with respect to punching shear than the models recommended in some national codes. The controlled perimeter has significant influence on the results and should be harmonized in prescriptive documents.

<p>The paper describes the final results of the project focused on the assessment of the existing railway bridges with respect to the wind load and traffic load in both ultimate limit state and equilibrium limit state. The outcomes of the project are based on extensive wind tunnel testing. Detailed probabilistic and reliability study is presented in this contribution using the wind tunnel data, and available railway traffic and wind speed data for a given location. The main result is a set of reduction factors for wind forces acting on specific railway bridge types and rail vehicles and calibrated combination factors for simultaneous action of unloaded train and wind in equilibrium limit state.</p>