A new mathematical model for elastic modulus prediction in mortar and concrete

Abstract

Tests were conducted on cylindrical mortar samples (10 cm in diameter and 20 cm in height) with a water-to-cement ratio of 0.4, cured at three constant temperatures (8 °C, 22 °C, and 40 °C) as well as under variable temperature conditions. Experimental results reveal that the rate of the dynamic elastic modulus development in the tested cement mortar blocks is solely influenced by the current temperature and the current dynamic elastic modulus. Based on this observation, an implicit relationship was proposed to characterize the rate of dynamic elastic modulus development, incorporating these two factors. Model parameters were determined using a combination of exhaustive search, least squares optimization, and iterative solution methods. Validation of the proposed model, achieved by comparing its predictions with experimental data, demonstrated the deviation of less than ±5 %. The results indicate that the linear temperature-based model provides a better fit than the Arrhenius function within the range of 8 °C–40 °C, with maximum relative errors of 3.41 % and 3.89 %, respectively. The model shows excellent agreement with the experimental data, highlighting its potential for accurately predicting the dynamic elastic modulus of cement mortar. Additionally, the proposed model has been further validated for its application and accuracy in estimating the elastic modulus of concrete with varying water-to-cement ratios (w/c), cement types, and curing temperatures exceeding 40 °C. These results demonstrate that the proposed model achieves high accuracy, with over 95 % precision.