Method of measuring lateral deformation of hardening concrete specimen under monotonous and cyclic loading

Abstract

The measurement of lateral deformation of hardening concrete finds its application in many concrete technology fields, as it is used for direct derivation of the Poisson’s ratio, which is necessary for multidimensional analyses. The soft consistency of hardening concrete prohibits any contact of a specimen with measuring equipment, therefore, a method using a CMOS camera to measure the lateral deformation of hardening concrete under uniaxial monotonous and cyclic loading is proposed. The presented method is based on processing of high-resolution images. The results obtained are in the form of a relation between the Poisson’s ratio and the stress-strength ratio. Also, the issue related to the large amount of free water contained in the hardening concrete, which affects the measurement, is discussed and a corrective measure is suggested.