A Simple Methodology to Measure the Dynamic Flexural Strength of Brittle Materials

Abstract

A simple methodology is proposed for measuring the dynamic flexural strength of brittle materials. The proposed technique is based on 1-point impact experimental setup with (unsupported) small beam specimens. All that is needed is a measurement of the prescribed velocity as a boundary condition and the fracture time for a failure criterion, both to be input in a numerical (FE) model to determine the flexural strength. The specimen was modeled numerically and observed to be essentially loaded in bending until its final inertial failure. The specimen's geometry was optimized, noting that during the very first moments of the loading, the specimen length does not affect its overall response, so that it can be considered as infinite. The use of small beam specimens allow large scale testing of the flexural strength and comparison between static and dynamic loading configurations. Preliminary experiments are presented to illustrate the proposed approach.Keywords Brittle material . Dynamic flexural strength .

Experimental Study of the Dynamic Flexural Strength of Concrete

“…This technique has been less frequently applied to un-notched specimen. Among the few applications, we can notice applications to very thin brick specimen (Delvare et al 2010), advanced ceramics (Belenky and Rittel 2011), aluminum bars (Pierron et al 2011) or to normalized concrete specimen (Hanus et al 2012). Concerning these works, it is worth mentioning that inertial effects play a prominent role and must be taken into account for accurate processing of the test data as discussed in the sequel.…”

Analysis of a Three-Bar Kolsky Apparatus for High-Rate Three-Point Flexure

“…1 This can be done without changing the target strain-rate, although it requires a different set of nodal velocities as determined by Eqs. (14) and (15). To see the effect of changing the length only, however, it is important to keep the strain-rate the same.…”

“…Single point bending is an additional approach, and has an advantage in that it avoids many alignment problems. Belenky and Rittel [14][15][16] have recently used a one-point bending technique to measure dynamic flexural strength of ceramics. In this technique, an incident bar is used to directly impact a free standing specimen.…”