Micromechanical Modeling on Compressive Behavior of Foamed Concrete

Abstract

Much attention has recently been paid to investigating the internal mechanisms between the void structures of foamed concrete and its mechanical behavior. This study adopted the X-ray computed tomography (X-CT) technique to build three-dimensional (3D) internal void structures of foamed concrete before conducting the unconfined compression test. A sensitivity analysis was conducted to evaluate the influence of the void structure on the mechanical properties. The results showed that the contacts between voids had a primary influence on the residual strength, and the void size was the major influence factor on the modulus. A micromechanical model was developed to simulate the mechanical behavior of the foamed concrete under compression, and good agreements were found with the test results. A simple equation was proposed to predict the mechanical properties of the foamed concretes considering the effects and variations of the void structures on the mechanical properties. Combining the equation with the micromechanical damage model, the variations of the mechanical behavior due to the difference in void structures can be well predicted.