2008 Volume 45 Issue 1 Pages 45-56
Stratum water and crack water through cracks of bedding planes and of joint surfaces give a great influence on the amount of displacement of moving mass in a landslide area. In this paper, at first, we examined the three-dimensional modeling of seepage flow analysis reflecting aspect cracks and then calculated water pressure distribution specifically by melting snow water in order to grasp a change of water pressure distribution of before-and-after construction of drainage facilities of well and drainage pipe. On that occasion, we made accurate modeling structure of various cracks and drainage facilities of well and drainage pipe. Using the results derived by the seepage flow analysis, we carried out a three-dimensional stability analysis. Based on the result of the stability analysis, we evaluated the stability of the landslide slope and the effect of drainage facilities. In OODAIRA Landslide area where landslides were reactivated by melting snow, by applying the above mentioned analysis, we were able to obtain the acceptable results that matches field situation between fluctuation of water pressure and displacement of moving mass. We were then able to simulate effectiveness of drainage facilities.
