Measurement of the compressive impact strength of concrete using a thin loadcell

Abstract

This Paper describes a method developed to measure the uniaxial stress-strain response of concrete loaded in compression at the high strain rates which occur during hard impact. Concrete cylinders, nominally 100 mm in diameter and 250 mm long, were impacted with a drop hammer, and transient measurements were recorded with electrical resistance strain gauges used in conjunction with a novel loadcell; the latter incorporating manganin pressure gauges. Particular attention is given to problems encountered with stress measurement when dynamic stress waves are present within the concrete specimen, especially when stress and strain are not measured at the same location.