Assessment of the deformation behavior of a tensegrity floor through photogrammetry

Tensegrity structures are interesting elements that can be used to create innovative building components. In this work, the deformation behavior of a new type of tensegrity floor (patent n. 0001426973) was investigated through image analysis and photogrammetry, using stereoscopic algorithms. The main innovation of the proposed tensegrity floor is the structural cooperation between glass tiles and steel components, obtained using suitable adhesive joints. In order to evaluate the deformation of the floor under different loading conditions a non-contact measurement system was developed and validated on a scale prototype of the floor. The used method is a stereoscopic optical technique based on the grid method, the validation was performed comparing the measured displacement with the one measured in the same floor with linear displacement sensors. The stereoscopic images were processed with Matlab®, furthermore, a combination of interpolation algorithms were employed to generate the full-field map of the displacement. Two configurations of the floor (with and without the adhesive joints) and three loading conditions were investigated. The analysis demonstrates that the adhesive joints produce a reduction of the overall deflection of the floor of about 60%, falling within the admissible values established by Italian building code. The measurement system is reasonably accurate and can be used in future applications where linear transducers cannot be installed.