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Abstract. The Digital Image Correlation (DIC) technique enables full field, noncontact measurements of displacements and strains of a wide variety of objects. An adaptation of the DIC technique for monitoring of civil-engineering structures is presented in the paper. A general concept of the complex, automatic monitoring system, in which the DIC sensor plays an important role is described. Some new software features, which aim to facilitate outdoor measurements and speed up the correlation analysis, is also introduced. As an example of application, measurements of a railway bridge in Nieporet (Poland) are presented. The experimental results are compared with displacements of a FEM model of the bridge.

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Boehmite particles modified with organic ligands were prepared through the reaction of boehmite with acrylic acid or diethylphosphoric acid (formed in situ from triethyl phosphate). The chemical structures of these particles were determined, and it was shown that they formed stable aqueous dispersions with a particle size lower than 200 nm (average diameter ¼ 40-100 nm, depending on the method of modification) for more than 90% of the population. These nanoparticle dispersions were mixed with carboxylated styrene-butadiene latex, and after water evaporation, homogeneous composites were obtained when the modifier concentration was in the range of 0.5-3 wt %. The mechanical properties of the composites were improved with respect to those of the unmodified rubber (tensile strength up to 200% and elongation at break up to 40%). The modifiers also improved some mechanical properties of rubbers cured with sulfur/N-cyclohexylbenzothiazole-2-sulfenamide/ZnO/stearic acid or ZnO/stearic acid systems.