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The performance of 61 global climate models participating in CMIP5 and 6 is evaluated for the Southern Hemisphere extratropics in terms of typical regional‐scale atmospheric circulation patterns. These patterns are known to be linked with a number of key variables in atmospheric physics and chemistry and provide an overarching concept for model evaluation. First, hemispheric‐wide error and ranking maps are provided for each model and regional details are described. Then, the results are compared with those obtained in a companion study for the Northern Hemisphere. For most models, the average error magnitude and ranking position is similar on both hemispheres, ruling out systematic tuning toward either of the two. CMIP6 models perform better on average than CMIP5 models and the interactive simulation of more climate system components does not deteriorate the results for most model families. Better performance is associated with higher resolution in the atmosphere, following a non‐linear relationship. Plain Language Summary: This letter provides a survey on the capability of global climate models to reproduce the regional atmospheric circulation in the Southern Hemisphere in present climate conditions. Climate models from the latest model generation are found to perform better on average than those of the previous generation and the obtained model ranking is similar to that found for the Northern Hemisphere in a companion study. While model performance is found to be generally unrelated to model complexity in terms of covered climate system components, better results are associated with higher model resolution in the atmosphere. Key Points: CMIP6 models perform better than CMIP5 models on averageSouthern Hemisphere model ranking similar to Northern Hemisphere rankingMore complex model versions perform similar to less complex ones [ABSTRACT FROM AUTHOR]

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The design of concrete structures is based on calculation rules, which often do not take into account the very early age behaviour of the material. However, during this period, structural concrete is subjected to strains due to the hydration process of cement. If these strains are restrained by concrete itself or surrounding boundaries, stresses start to build up that can lead to the formation of cracks. Among the parameters involved in the stress build up, the stiffness evolution is of major importance. This paper reports the use of eight different techniques aimed at stiffness evolution assessment, applied on the same concrete mix, in a round robin experimental test within three laboratories. The observations are compared after having expressed the results at the same equivalent age. Both the loading stress rate and amplitude are observed to have an effect of limited importance on the determination of the quasi-static elastic modulus, which might be explained by very short term creep. Ultrasonic measurements provide values of E-modulus that are higher than the values provided by the quasi-static tests at the time of the concrete setting. Similar mechanisms associated to very short term creep could explain the difference between the quasi-static and high-frequency elastic modulus. [ABSTRACT FROM AUTHOR]

The elastic modulus evolution of cementitious materials since early ages can be experimentally measured with the EMM-ARM (Elastic Modulus Measurement through Ambient Response Method) test. This methodology has been extensively validated, but its original implementation relied on costly proprietary platforms. A minimalist, open-source test system may provide a benchmark that sets minimum requirements and performance to enable the development of tailor-made systems. This work aimed to develop, characterise, and validate such system, composed of data-acquisition hardware and post-processing software. Characterisation results showed the system had a spectral noise floor of 2.1 × 10−8 g2/Hz, an RMS noise of 0.003 g, a sampling frequency variability of ± 0.006%, and an average power consumption of 41.53 mAh. Compared to an original EMM-ARM system, validation results indicated the proposed system had an absolute error lower than 0.3% from 1 day of testing onwards, with a similar coefficient of variation of 1.2%. [ABSTRACT FROM AUTHOR]