[in Japanese]

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In case of evaluating the stability of a slope, FEM analysis is highly accepted because it describes the behavior of engineering structures. But the determination of the total safety factor in a slope using this FEM analysis is difficult because it is used to find out only the local safety factor.
The authors improved a FEM program in order to calculate the total safety factor with the pore water pressure.
Using this program, the authors evaluated quantitatively the effects of pore water pressure on the total safety factor of the slope.

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Prestressed anchors are often used for landslide control, and many problems remain unsolved in design of anchor works.
The stress in sliding mass and along sliding surface of landslide slopes with anchors of a certain initial force, and stress in these slopes which become unstable due to the build up of pore water pressure, are analyzed by using finite element method.
The following conclusions as a result:
(1) Each anchor which are arranged in different height have different force acted if the prestress of the anchor is small.
(2) Adequate initial anchor force is equal to one to achieve the desired factor of safety of a slope as 1.0. Then, the slope keeps stable and its deformation are controlled as the minimum by acting smaller anchor force.

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This paper discussed the estimation method of gravity waves generated by falling block into water body. Numerical investigation for these waves was made by the mean of boundary element method. Numerical results obtained by the presented methods were compared with experimental data and analytical solutions.

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This report introduces a criterion of the designs of the pile works in the Itakura National agricultural landslide prevention works.
When the landslide block is soft earth mass with N values less than 8, no reactional force of the landslide block to the pile is expected, the strength of the pile has to be calculated not to be bent and not to be sheared.
When the landslide block is hard with N values more than 8, and the pile is constructed in the tention zone of the landslide block, the strength of the pile has to be calculated not to be bent and not to be sheared. The reactional force of the landslide block to the pile is expected.
When the landslide block is hard with N values more than 8, and the pile is constructed in the compression zone of the landslide block, the strength of the pile has to be calculated not to be sheared. The reactional force of the landslide block to the pile is expected.

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