Prediction of relative dynamic elasticity modulus by extending a grey system theory

Abstract

The relative dynamic elasticity modulus is an important evaluation criterion in frost resistance testing of concrete. Generally, in order to validate the decay rules of concrete durability, the measurement of relative dynamic elasticity modulus needs a large number of testing data over time. Therefore, it is often difficult to carry out this test and sometimes it is even not feasible due to cost consideration. In addition, the dynamic relationship between the relative dynamic elasticity modulus and freeze–thaw cycle is very intensive, but so far there is no definite explicit or implicit function to describe it. However, the relative dynamic elasticity modulus of a concrete material can be measured indirectly with the grey prediction model based on a grey system theory that only requires a limited number of discrete data to estimate the behaviour of a dynamic system with uncertain and incomplete information. In this paper, we developed an indirect measurement model of concrete relative dynamic elasticity modulus with the number of freeze–thaw cycles as a leading indicator on the basis of an improved grey prediction model. The improved grey prediction model is established with the Taylor approximation method. We validated the effectiveness of the proposed model by using the relative dynamic elasticity modulus of the concrete material and corresponding experimental data concerning the number of freeze–thaw cycles.