摘要:While examination of the durability of ordinary concrete mixtures is of interest of many research groups, only limited amount of information is available in terms of lightweight concrete tested under the same conditions. In this case, the durability related to the chloride ion diffusion is investigated on the relatively new type of structural lightweight concrete, which, above all, contains waste material – red ceramics sand, and artificial expanded clay coarse aggregate. Used aggregates were fully soaked before adding into the concrete mixture, so also the internal curing effect is considered in terms of the degradation process. Cylindrical specimens made of plain concrete matrix and with added fibre in various percentage quantities were tested to examine the durability of the mixture by measuring the electrical resistivity. The results are compared to the findings from a similar project. The paper deals with aspects influencing the results of chloride diffusion in concrete.