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Determination of the current condition, load-bearing capacity, and reliability of the existing structures is often a greatly time-consuming and complex task. There are two main approaches how to evaluate the condition of existing structures and find out the response of the structure under acting loads. The first method is to perform an analytical or numerical analysis of the structure. This method is often used, but the accuracy of the outcomes deeply depends on the input parameters used in the analysis. Alternatively, if the input parameters are not clearly known or the exact behavior of the structure during loading is required, the best way how to evaluate the structure is to perform a full-scale load test. This paper describes the process of preparation, execution, and evaluation of the in situ full-scale load test of the bowstring arch reinforced concrete bridge built between the 1920s and 1930s damaged during the Second World War, repaired in the 1970s with no further maintenance later on. [ABSTRACT FROM AUTHOR]

Concreting in hot weather is usually very demanding. One of the most important aspects is correct curing of the concrete. The crucial factor is not only quality but also the time of curing. Insufficient curing of concrete may result in a decrease in its basic parameters, a decrease in the quality of the surface layer or a massive development of shrinkage cracks. All this may have a very negative impact on the durability of the concrete structure. This paper is about the influence of the concrete curing time on its compressive strength and on the modulus of elasticity. To determine the modulus of elasticity, two non-destructive methods were used – ultrasonic pulse velocity test and resonance method – and also a static test. The results presented show that the concrete curing time has a clear impact on its quality and it is, therefore, not advisable to underestimate this aspect of summer concreting. [ABSTRACT FROM AUTHOR]