Micromechanical analysis of cement stabilized macadam material in uniaxial compression test

Abstract

Cement-based composite is a kind of heterogeneous and discontinuous material. It is not appropriate to conduct stress analysis on a model constructed by continuous mean theory when subjected to external loads. A granular flow model based on discrete element theory is constructed to simulate the dynamic process of cementstabilized macadam during uniaxial compression test in this article. The appropriate contact bonding model is selected, and the contact parameters are calibrated. After the uniaxial compression test in the laboratory, the relative displacement, stress transfer process and crack propagation between aggregate particles in the structure are verified by the results calculated by the model. It can be seen from the research results that the parallel bond model can well reflect the mechanical characteristics of cementstabilized macadam. In the process of the specimen being loaded, the vertical displacement between particles leads to the specimen being compacted, and the horizontal displacement between particles leads to the crack. The displacement angle of cementitious particles in the upper model is larger than that of coarse aggregate. The displacement angle of cementitious particles in the lower model is less than that of coarse aggregate. The particle displacement angle generally shows a decreasing trend.