Abstract
We propose a method of multiscale numerical experiments for evaluating disaster-reductoin characteristics of tide-protection forest against tsunami energy. To conduct the experiments in a hierarchical way, a tide-protection forest is stratified into three spatial scales; the branch-scale is the smallest, the forest-scale is the largest and the tree-scale is intermediate. Tide-Protection Forest is assumed to be porous media and we identify its porous term as reduction characteristics. With the help of the stabilized finite element method, several cases of lower-scale analyses are carried out with different initial and boundary conditions to construct a response surface of the overall resistances at the upper-scale. Thus, with this information about the porous medium's characteristics, a whole costal region can be a analysis target with relatively low computational cost to make a risk assessment for structures behind the forest.