Abstract During the Great East Japan Earthquake and Tsunami of 2011, enormous coastal levees collapsed as a result of tsunami overflows. Concrete-covered levees, where concrete blocks are used to protect levees made of soil, showed a specific failure mode in which back slope blocks and internal soils were dislodged. Although several hydraulic experiments have been conducted in an attempt to understand the failure mechanism, the complexity of the failure requires that both hydro-dynamical and geotechnical points of view be taken into account for a deeper understanding. This study uses a centrifuge to identify the failure behavior of levees from those points of view. The centrifuge can reproduce the stress, water pressure, and overflow velocity of the prototype-scale ground. Overflowing at sufficient time periods was produced in the centrifuge by generating differences in water height for seaside and landside areas. The test results showed that the levees collapsed due to a combination of the effect of water flow on the back slope and seepage inside the levees. In addition, the effectiveness of several proposed countermeasures for preventing collapse was confirmed.

中文翻译：

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溢流和渗流复合作用下的混凝土堤防坍塌

摘要 在 2011 年东日本大地震和海啸期间，海啸溢出导致巨大的沿海堤坝倒塌。混凝土覆盖的堤防，其中混凝土块用于保护由土壤制成的堤防，显示出一种特定的破坏模式，其中后坡块和内部土壤被移走。虽然已经进行了几次水力实验以试图了解破坏机制，但破坏的复杂性需要同时考虑水动力和岩土工程的观点，以便更深入地了解。本研究使用离心机从这些角度识别堤坝的失效行为。离心机可以再现原型规模地面的应力、水压和溢流速度。通过产生海边和陆侧区域的水高差异，在离心机中产生了足够时间的溢流。试验结果表明，堤防坍塌是由于水流对后坡的影响和堤内渗流的共同作用。此外，还证实了一些建议的防止倒塌对策的有效性。