Dynamic response characteristics of artificial dam body under gas explosion shock wave

In order to study the impact of gas explosion shock waves on the mechanical properties of artificial dams, concrete specimens were made using river sand, crushed stones, Portland cement, dynamic and static loading tests were conducted. The stress-strain relationship of the material under stress was analyzed, and the direct impact of strain rate on the mechanical properties such as strength and deformation of the specimens was explained. A dynamic constitutive model of the material was constructed. The results show that in the static compression experiment, the stress-strain curve of the specimen is divided into four stages, with an average peak stress of 38.27 MPa, an elastic modulus of 30.4 GPa, and a Poisson’s ratio of 0.291. In the SHPB test, when the impact velocities are 4.8, 5.5, and 7.8 m/s, the specimens exhibit “fracture”, “fragmentation”, and “crushing” states, respectively. The strain rate of the specimen is positively correlated with the fracture stress, with an average strain rate in the range of 100-250 s⁻¹. The peak stress of the specimen slowly increases and tends to stabilize with the increase of the average strain rate; the curve fitting degree R² of the improved ZWT constitutive equation is 0.98, which fully shows that the improved constitutive model has a good performance on the dynamic stress-strain relationship before the peak stress of concrete.