GUIDELINES FOR DETERMINING LOAD AND ACTIONS ON HISTORIC RAILWAY BRIDGES

According to Polish Construction Law, each structure, including those entered in the register of monuments, should ensure safety and serviceability by maintaining the proper technical condition in the expected period of use. Unfortunately, the legal regulations are not straightforward. Therefore, the same load models are used to structures that are to be built and will operate for at least 100 years, and to the existing structures that have been in service, also those operated for 100 years, that the Administrator intends to continue to use safely for additional time, e.g. another 50 years. Such an approach is contrary to the principles of technical knowledge referred to in the Polish Construction Law, as the value of the majority of non-vertical loads and actions assumed as per the design standard results directly from the vertical service load. This paper proposes the values of loads, which are derivatives of the vertical service load, that could be used for the evaluation of existing railway bridges and viaducts, especially those entered in the register of monuments.