Abstract: Free fall,incipient motion,and cessation of motion experiments were conducted to investigate the anti-scour and anti-slide stability characteristics of new modular blocking bodies.The study analyzed the influence mechanisms of geometric configuration,block size,flow velocity,and friction coefficient on stability performance.A stability numerical model based on Computational Fluid Dynamics (CFD) was established,which simulates the falling displacement and incipient velocity with high accuracy.The results indicate that the spherical cone demonstrates superior stability compared to other configurations.Under similar volume conditions,the spherical cone exhibits 23% to 75% higher incipient velocity than other blocking bodies,and its horizontal falling displacement remains the minimum across all tested flow velocities.The falling displacement decreases with increasing block size and presents a significant nonlinear positive correlation with flow velocity.Both incipient and cessation velocities increase with higher bed friction coefficients and larger block sizes.Consequently,the maximum incipient velocity of the spherical cone reaches 5.84m/s.