Carboxymethylcellulose (CMC) and ultrasound gel (USG) seem to be suitable clear model fluids to substitute real ultra-high-performance concretes (UHPCs), enabling experimental monitoring of events occurring within these mixtures at similar flow behaviour. USG is eligible for UHPC mixtures with significant yield stress. CMC having a suitable concentration is better for UHPCs exhibiting indistinct yield stress. The rheological behaviour of real UHPC mixtures as well as substituting model fluids was measured using a non-standard system consisting of a vessel stirred by an anchor or a screw agitator. In addition, a standard rotational rheometer system with concentric cylinder geometry was used for optimization of the above-mentioned method of measurement and also for measuring the rheological parameters of the substituting model fluids. This article deals with the methodology for measuring the rheological properties of these substances and presents the results of the measurements using flow curves and rheological models.

The homogenization of the agitated batch and ensuring the suspension of particles are the most frequently encountered requirements in terms of mixing applications. These operations are affected by the flow of the agitated batch. The geometrical parameters of the mixing system, especially the shape of the agitator blade, affect flow and circulation in the agitated batch. The present work provides a general description of the most common processes in the agitated batch (blending and particle suspension), hydrodynamic parameters (flow in agitated batches, pumping and circulation capacity of impellers) and the geometrical configurations of the mixing equipment (shape of vessel, baffle and impeller, and their mutual arrangement) that influence the process. The dimensionless process characteristics of the agitator were derived by theoretical analysis. These characteristics were applied to evaluate an extensive set of experimental data with various geometric configurations of the mixing equipment. This study shows how the flow in the agitated batch, caused by the pumping and circulating effects of the agitators, affects the parameters and energy efficiency of these processes, depending on the geometric configuration of the mixing equipment. Moreover, the benefits of the hydrofoil impellers used for these mixing processes are presented.

In recent years, the field of structure monitoring has been making increasing use of systems based on fiber-optic technologies. Fiber-optic technology offers many advantages, including higher quality measurements, greater reliability, easier installation and maintenance, insensitivity to the environment (mainly to the electromagnetic field), corrosion resistance, safety in explosive and flammable environments, the possibility of long-term monitoring and lower cost per lifetime. We have used SOFO fibre-optic strain gauges to perform measurements to check the overall relative deformation of a real reinforced concrete structure. Long-term monitoring of the structure revealed that the measurement readings obtained from these fibre-optic strain gauges differed from each other. Greater attention was therefore paid to the calibration of the fibre-optic strain gauges, and to determining their measurement accuracy. The experimental results show that it is necessary to calibrate SOFO strain gauges before they are used, and to determine their calibration constant.

The aim of the article is to compare the experimental investigation of deflection of the sandwich composite beam with theoretical models. The experimental test specimens were composed of three layers. Skins were made using epoxy-resin-impregnated glass laminates with plain weave. The light weight foam Divinycell H100 was used as sandwich core. The three-point bending test was carried out. Fibre-optic strain gauges, SOFO SMARTape Compact deformation sensors, were used for determining the deflection of the sandwich composite structure. Experimentally obtained data were used for comparison with theoretical models -sandwich theory with the transverse shear, sandwich theory without the transverse shear, laminate theory with the transverse shear and laminate theory without the transverse shear.

The aim of this article is proposition of new methodology of experimental analysis of long-term monitoring of sandwich composite structures. The sandwich composite structures are, due to its properties like stiffness, high impact strength, corrosion resistance, low thermal conductivity and low acoustic conductivity and, commonly used in civil engineering in recent years. This type of structure is composed of two main parts (face sheet and core) having different material and mechanical properties. Sudden change of these properties causes interlaminar stress in structure. A good knowledge about behaviour of sandwich composite structure is important for efficient manufacture techniques, long-term prediction of structure behaviour and for economics. The experimental part has been focused on obtaining the experimental results of deformation between layers of sandwich composite structure during long-term monitoring. The long-gauge optical fibres SOFO ® SMARTape Compact have been used for longterm monitoring of sandwich composite structures. Long-gauge optical fibres were placed between the foam core and an outer layer of the composite structure during manufacturing. Test specimens were loaded in three-point bending test.