Dynamic response and failure modes of jointed rock slopes under blasting: A numerical investigation

To investigate the dynamic response characteristics of jointed rock slopes under blasting loads, a numerical model was established in LS-DYNA with different joint configurations and slope geometries. The vertical cross-section along the blasthole axis was selected as the analysis plane to investigate the dynamic disturbance induced by single-hole blasting at the slope toe in the overlying jointed rock mass. Peak particle acceleration, peak particle velocity, and peak displacement were used as key indicators to systematically assess the influence of joint characteristics in the dynamic response and failure modes of the slope. The results show that joints significantly alter the propagation of blast-induced stress waves and introduce pronounced anisotropy in the dynamic behavior of the slope. Compared to the slope angle, the joint inclination angle plays a more decisive role in controlling the magnitude of the dynamic responses. When the joint thickness increases to 0.5 m, its influence extends beyond acceleration to include velocity and displacement. Failure modes are governed by joint geometry, while steeper slope angles aggravate rock fragmentation in the retained rock mass, thereby compromising overall stability. Furthermore, the coupling effect of joint distribution and slope configuration enhances the intensity of the surface response and accelerates the progression of instability, highlighting the critical controlling role of joint geometry in blasting-induced slope failure.