Details of the failure characteristics of composite-type breakwaters reinforced by rubble have not been clarified, including the prehension of some failure modes and the conditions that cause each mode. In this study, details of the failure characteristics and a performance assessment method were studied using two approaches, namely, centrifuge model tests and a circular slip analysis. The model tests showed that sliding failure could occur when the friction between the mound and the caisson was low, the caisson was wide, and the reinforcing embankment was high and/or wide. In contrary cases, bearing capacity failure was liable to occur. Basically, the larger the reinforcing embankment size, the greater the strength and stiffness. The performance assessment using a circular slip analysis and considering failure modes was verified through discussions. The analysis resulted in the underestimation of the stability of the reinforced breakwaters when the rubble was angular. However, the caisson moved to a certain degree even with a relatively lower load and the displacement reached that which is allowable by the structure. Consequently, a circular slip analysis was deemed suitable for evaluating the performance of reinforced breakwaters.

尚不清楚由碎石增强的复合型防波堤的破坏特性的细节，包括对某些破坏模式的理解以及导致每种破坏模式的条件。在这项研究中，使用两种方法，即离心机模型试验和圆滑分析，研究了故障特征的细节和性能评估方法。模型试验表明，当土墩与沉箱之间的摩擦力低，沉箱宽，加筋路堤高和/或宽时，会发生滑动破坏。相反，很容易发生承载力故障。基本上，加强路堤的尺寸越大，强度和刚度就越大。通过讨论验证了使用圆滑分析并考虑故障模式的性能评估。该分析导致低估了碎石成角形时加筋防波堤的稳定性。然而，即使在相对较低的载荷下，沉箱也移动到一定程度，并且位移达到了该结构所允许的位移。因此，圆滑分析被认为适合评估增强防波堤的性能。