Abstract: A physical model of identical spherical charges that explode synchronously was built in this research to investigate the rock-breaking characteristics of stress wave superposition between explosive packages in different sources. According to the stress state after stress superposition between two spherical charges, the function of peak stress with oblique superposition is established. Furthermore, LS-DYNA software is employed to build an equivalent numerical model to verify the formulae obtained as aforementioned. The range of rock-breaking angle (β) where the rock can be easily destroyed is acquired as arctan λ≤β<90° (λ is the coefficient of lateral compressive stress). A sequence of peak points in stress superposition area was selected as unit points to obtain the curve of numerical stress change. The theoretical result of peak stress trend is consistent in general with the numerical result, implying that the rock-breaking characteristics in stress superposition process of spherical charges in the present research accord well with theoretical characteristics. The results offer theoretical reference and guidance for blasting project with spherical charges.

Key words: blasting stress wave, stress wave superposition, rock breaking angles, rock breaking characteristics, spherical charge