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Abstract-This contribution compares concrete structure design results obtained via the partial reliability factor method and using a probability-based method. The Monte Carlo simulation method, modified by the Latin Hypercube Sampling method, was used to calculate the reliability of a designed structure. Economic and ecological aspects (acquisition costs, CO 2 and SO 2 emissions and embodied energy associated with the concrete member through the production, utilization and demolition stages of its life cycle) were taken into account when assessing the quality of the design. An example of a designed structure -a prestressed spun concrete pole manufactured from reinforced concrete -is presented.

During the reconstruction of a university in Olomouc (Czech Republic) it was discovered that the concrete used in one load-bearing structure was of insufficient strength. The university building complex was constructed in the years [1955][1956][1957][1958][1959][1960]. It is built from a reinforced concrete skeleton. The four-storey building is founded on RC footings and continuous footing. A detailed structural investigation of the structure of the first floor determined that the strength of the used concrete varied, ranging from concrete class C3/3.5 to C12/15. The original designed concrete class was C10/13.5, while the plain reinforcement utilised according to the original design was steel with a design strength of 180 MPa. Three structural repair variants were designed based on construction surveys:• steel bandages for the columns and girders, and strengthening/supporting of the girders via steel cross-beams fitted to the bandages;• steel bandages for the columns and girders, and strengthening of the girders via prestressing tendons;• additional non-prestressed reinforcement of the structure by covering it with sprayed concrete.Based on the economic (cost), structural and technical aspects (minimising of additional load), the variant using bandages with additional external prestressing of the majority of the girders via tendons was preferred.