The explosion of a building generates plenty of debris that flies far away. The flying debris is hazardous because it contains large amounts of kinetic energy. Therefore, determining the safety distance from the debris is essential. However, debris ricochet that collides onto the ground affects the safety distance because the ricochet phenomenon is influenced by the condition of the medium. In this study, experiments and finite element analysis were performed to investigate the ricochet based on the water content of sand. From a direct shear test, the internal friction angle and cohesion of sand were obtained based on the water content. The effects of internal friction angle and adhesion on the yield stress and ricochet were investigated. The results indicated that as the water content increased, the internal friction angle increased and then decreased, and the cohesion continued to decrease. The yield stress was proportional to the internal friction angle and inversely proportional to adhesion. Therefore, lower yield stress resulted in deeper penetration of debris, leading to higher energy loss, which increased the kinetic energy loss factor. Thus, the condition of the medium should be considered for setting a proper safety distance suitable for the surrounding environment of the building.

建筑物的爆炸会产生大量碎片，这些碎片会飞到很远的地方。飞行碎片很危险，因为它包含大量动能。因此，确定与碎屑的安全距离至关重要。但是，碰撞到地面的碎片弹跳会影响安全距离，因为弹跳现象受介质状态的影响。在这项研究中，进行了实验和有限元分析，以基于沙子的含水量研究the。通过直接剪切试验，基于水含量获得了内摩擦角和内聚力。研究了内摩擦角和附着力对屈服应力和跳弹的影响。结果表明，随着水分含量的增加，内摩擦角先增大后减小，内聚力继续减小。屈服应力与内摩擦角成正比，与粘附力成反比。因此，较低的屈服应力导致更深的碎片穿透，从而导致较高的能量损失，从而增加了动能损失因子。因此，应考虑使用介质的条件来设置适合建筑物周围环境的适当安全距离。