Experimental and numerical studies on the mechanical behaviors of basic magnesium sulfate cement concrete under dynamic split-tension

Dynamic splitting-tensile tests were conducted on basic magnesium sulfate cement concrete (BMSCC) at three different water-cement ratios using a 75 mm diameter split Hopkinson pressure bar (SHPB). The failure process of BMSCC under dynamic splitting loading was simulated using the finite element software LS-DYNA and a random aggregate mesoscopic model. The results demonstrated the strain rate effect in BMSCC, where the dynamic splitting-tensile strength increased with higher strain rates. Furthermore, the strength grade of the material significantly influenced the growth rate of peak stress, with higher strength grades exhibiting faster rates. The dynamic increase factor (DIF), a parameter characterizing the dynamic behavior of brittle materials, exhibited a linear relationship with the logarithm of strain rate. The LS-DYNA software was employed to numerically simulate the dynamic splitting-tensile process at the meso-scale, yielding satisfactory results with relative errors of 12.7%, 6.3%, and 3.3% for the dynamic splitting-tensile strength at different water-cement ratios, respectively.