A mathematical model for predicting complete compressive stress-strain curve of plain and short fiber reinforced clay adobes

Following the principles of low-cost, energy-saving, low polluting, and sufficient thermal, humidity and acoustic insulation of soil blocks as a construction material, there is an increasing interest to study clay adobe elements. This study presents a mathematical model for predicting the relationship between uniaxial compressive stress and corresponding strain which can be useful for simulating the structural behavior of plain and short fiber reinforced adobes with concrete damage plasticity model in ABAQUS.  In this direction, the compressive properties of four different plain and short fiber reinforced adobes weremeasured in experimental tests. From the obtained results, the essential parameters of the stress-strain curves for all various mix design specimens were extracted for numerical modeling.  By a statistical study on the various results of compressive tests as available in the related literature, the proposed equations were developed for predicting the necessary parameters when the only needed experimentally determined parameter is the peak compressive stress. The suggested model is compatible with the behavior of different adobes with different compositions, compacting, curing, and testing condition. The recommended model and formulations are to some extent more successful in predicting the linear and nonlinear behavior of different adobes according to other models.Finally, a mathematical model is developed for predicting the inelastic range of the compressive stress-strain curve.