Temperature Drop Model Based on Discrete Element Method for Simulating Damage of Bio-Cemented Sand by Cold Wave

The microbially cemented sand (MCS) material is a new building material with a broad research prospect, although the nationwide cold wave affects the mechanical properties of the material in the practical application. The microstructure of MCS is obtained by computed tomography (CT) and scanning electron microscope (SEM); the thermodynamic mathematical model is established by considering the particle shapes and bonding state based on direct element method (DEM). By studying the damage of temperature drop amplitude and cooling duration to MCS material under the effect of cold wave, the following conclusions are drawn. For a given temperature drop range, an increased cooling time can aggravate the material damage. In addition, a rapid drop in temperature can cause serious damage to the material. The cracks generated by the temperature stress propagate in the direction of the weaker component of the material. The DEM model can be better used to analyze the damage of the MCS structure induced by cold wave. © 2019, Shanghai Jiao Tong University and Springer-Verlag GmbH Germany, part of Springer Nature.