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The sustainability of concrete and concrete structures is seeing increased attention; among other things, this is because 5% of global CO2 emissions are produced by cement manufacturing. Responsible sustainability management requires effective tools for the quantification, i.e. measurement, or comparison of material, technological, and structural options. This is why there are a number of initiatives and approaches that aim to reduce global greenhouse gas emissions. Their project design uses techniques that assess whole structures and their usage; however, most of their input data is based on estimates. This paper presents a validation of a method of designing, assessing, and predicting sustainability for one material (concrete) with regard to its composition, relevant properties, and predicted value dispersion utilizing probabilistic approach.

A The article is based on the authors' many years of experience in providing laboratory proficiency testing including organization of proficiency testing by interlaboratory comparison. In the introduction are compared the basic tests in the field of aggregates, based on their coefficient of variation. Another part details the influence of each testing stage (sampling, sample preparation and the test itself) on the accuracy of the test results and proposes possible measures to reduce their variance.

The paper deals with an experimental analysis focused on the determination and evaluation of the early age shrinkage strain using Shrinkage-Cone. The measurements were performed on the cement pastes and mortars with a different w/c ratio. The authors propose a new approach to the measurement evaluation based on the determination of time-zero at the time of estimated initial setting determined as the time when the internal temperature of specimens started to rise. In this case, also the effect of the thermal expansion is taken into account in the evaluation.

The paper focuses on determining the frost resistance of concrete using selected destructive and non-destructive test methods. The experiment was performed with four specially made concretes, which differed only in the origin of sand and coarse aggregate. The primary outcome of the experiment are the differences in frost resistance as measured by different methods. In addition, it briefly describes the influence that the choice of aggregate has on the frost resistance of concrete.