An experimental investigation of the flexural strength of soda–lime–silica glass at high loading rates

A novel ring-on-ring test setup was developed for investigating the biaxial flexural strength of small circular soda–lime–silica glass specimens at high loading rates in a high-speed test rig. Such rate effects becomes important when designing for extreme events such as impact and blast, which are highly relevant for glass used in e.g. façades. The investigation focused on two groups of specimens with different surface conditions: as-received and pre-damaged with a well-defined flaw. A total of 151 specimens were tested in order to evaluate the influence of loading rate and surface condition on the flexural strength. Quasi-static and dynamic experiments were performed at loading rates ranging between 2 and 5.6 × 106 MPa/s. An 85% increase in strength with loading rate was observed for the ‘as-received’ specimens and 52% for the ‘pre-damaged’.