Accounting of loading system stiffness in tests on scaled-down wide-meshed composite specimens

The importance of 'loading system' was noticed in terms of investigations of deformation and material damage processes. The paper presents a technique, which allows accounting of loading system stiffness coefficient in tests on large-size, scaled-down or nonstandard specimens by using noncontact digital optical displacement and strain fields measuring system, its software is based on digital image correlation technique. Time-curves of specimens and the loading system elongation, counted by load cell of test system and by using optic method. Qualitative and numerical assessments were carried out for influence identification of special gripping devices on loading system stiffness. Stiffness coefficients are presented as well.