Development of tsunami fragility evaluation methods by large scale experiments. Part 2. Validation of the applicability of evaluation methods of impact force due to tsunami floating debris

In order to examine the applicability of the existing estimation equations of the impact force due to tsunami floating debris, the collision tests are carried out. In the experiments, logs and full-scale light car are used. In this report, two types of existing equations, one is based on the Young's module of the debris (Eq.A) and the other one is based on the stiffness of the debris (Eq.B), are focused on. The estimated impact forces using Eq.A with log's Young module obtained by the material test agree with measured forces obtained by the collision test. But Eq.A does not applicate to a car because it is not easy to determine the Young's module of a car. On the other hand, the estimated impact forces using Eq.B with car's stiffness obtained by the static loading test agree with measured forces obtained by the collision test. This indicates that Eq.B unable us to estimate impact force of the floating debris such as car if the stiffness of the debris is determined. (author)