Full-Field Strain Measurement of Concrete Specimen in Three-Point Bending

In mechanical testing of concrete specimens under three-point bending, the material is a typical heterogeneous brittle medium: during bending, the strain distribution is highly non-uniform, and cracks often initiate locally in the tension zone and propagate rapidly. Traditional displacement transducers or extensometers can only provide mid-span deflection or single gauge length information, and can hardly reveal the crack initiation location, the degree of strain concentration, or the damage evolution process. To meet this testing need, Haytham Technology, based on DIC (digital image correlation) technology, provides a full-field strain measurement solution for three-point bending tests on concrete.

Haytham DICThrough optical imaging and correlation analysis, the surface features of the specimen are continuously tracked, obtaining full-field displacement and strain distributions during bending loading without contacting the specimen. Compared with traditional macroscopic measurement methods, this approach clearly presents the strain gradient changes between the tension and compression zones of concrete under bending, accurately captures crack initiation, propagation, and through-cracking, and provides an intuitive basis for flexural-tensile performance analysis.