胶结颗粒材料是在常规散粒体基础上发展而来的新型防护材料，可有效提升海堤和海上风电基础等结构在波流作用下的抗冲刷性能，具有较好的工程应用前景。然而，现有胶结颗粒材料的设计方法多基于有限的小规模试验数据，缺乏系统理论指导，制约了其进一步推广。为此，该文首先提出了一种考虑两相流和非规则颗粒形态的计算流体力学-离散元法耦合数值仿真方法，并采用团簇颗粒模拟真实堆石料形状，构建颗粒-孔隙体系；其次，定义胶结键空间分布，引入胶结键模型和多孔介质模型，系统分析了胶结后材料的宏观力学性能；最后，模拟了波浪冲刷条件下胶结颗粒材料的动态响应过程，揭示了两相流分界面演化、颗粒运动机制、流固相互作用和胶结键断裂演化等关键机理。结果表明：胶结作用并非仅通过增强颗粒间连接提升抗冲刷能力，其核心机制在于胶结体对孔隙的填充显著降低了堆石体内部渗透深度，并重构了力链传递路径，且这种提升效果在胶结比超过一定水平后显著饱和。该文通过建立精细化数值模型，为深入理解胶结颗粒材料的抗冲刷机制提供了一种科学的解决方案。

Objective: The resilience of coastal and offshore infrastructure against wave-induced scouring is a critical concern. Cemented granular materials (CGMs), which strengthen mass stability through interparticle bonds, present a potential solution. However, their design is limited by a lack of understanding of microscale fluid–solid interactions under dynamic hydraulic loading. This study aims to create a high-fidelity numerical framework to investigate these anti-scouring mechanisms, focusing on cementation distribution and two-phase flow. Methods: A coupled computational fluid dynamics and discrete element method (CFD-DEM) model was developed to simulate the complexities of two-phase flow (water and air) and irregular particle shapes. The model was based on a validated virtual domain/immersed boundary method. Realistic rubble shapes were modeled using clumped particles, where each irregular grain was represented by a rigid cluster of sub-spheres. The pore structure was analyzed via Voronoi tessellation, and a mesoscale bond model was implemented to define the spatial distribution of cementation. Bonds, generated as cylindrical elements connecting particle centers, were created if the Voronoi faces met a criterion based on a critical interparticle distance related to the cementation ratio (CR), which was the volume of cement over the total volume. These bonds followed a linear elastic model with tensile and shear strength limits; they broke once these limits were exceeded. To account for flow obstruction caused by cement within pores, cemented zones were modeled as an isotropic homogeneous porous medium using a Darcy–Forchheimer approach, with momentum sink terms added to the fluid equations. The DEM module (using LIGGGHTS) solved the translational and rotational motions of each clumped particle, considering contact, bond, and fluid forces. The CFD module (using OpenFOAM) solved the Navier–Stokes equations for the two-phase fluid. Coupling was achieved through momentum exchange, where fluid forces acted on particles, and particle motion constrained the fluid velocity via porosity-weighted correction. A dam-break wave scenario was simulated in a 3D numerical flume to scour a triangular rockfill mound composed of 292 clumped particles, representing a transient high-impact loading condition. Simulations were carried out for noncemented and cemented cases with CR values of 10%. Results: The model successfully replicated the fluid and contact force dynamics observed in noncemented rockfill. For the cemented cases, key findings included: the following: (1) Permeability control: cementation significantly reduced water infiltration. The noncemented mound exhibited deep seepage, while at CR = 5%, penetration was greatly decreased. At CR = 10% and 20%, water was mainly confined to surface flow, with minimal internal seepage. The effect saturated, with little difference between CR = 10% and 20%. (2) Micromechanical response: cementation bonds changed how internal forces were transmitted. They supported substantial tangential forces during wave action, and their progressive failure (via tensile/shear rupture) dissipated energy. This led to a decrease in the average normal contact force and an increase in tangential force, indicating dynamic rearrangement of force chains. (3) Structural integrity: despite similar peak fluid impact forces, cemented structures retained greater stability by stabilizing the granular skeleton and redistributing internal stresses through the bond network. Conclusions: An advanced CFD-DEM model is developed to reveal the micromechanisms behind CGMs' resistance to scour. Cementation improves performance not only by strengthening contacts but also by reducing permeability and enabling energy dissipation through bond failure. The effect of cement content is nonlinear; beyond around 10% CR, additional cement shows diminishing returns, which is important for cost-effective design. Future work will include more complex material models and realistic wave conditions to support engineering applications.