Abstract
To investigate the index for the 3-D displacement measurement of landslide, the system of 3-D measurement was constructed for laboratory model test with basis of photogrammetry. The experiment simulated the landslide by raising the groundwater level at the up stream side. About 50 markers were set on the slope and 3-D displacement of slope surface was analyzed. The change in areal strain distribution was calculated and compared with the location of crack of failure. It was found that the location of increasing areal strain coincides with the location of crack and that the areal strain was important index for 3-D displacement measurement. Moreover, it was found that the change in normal direction of slope surface was a possible index to know the failure aspect. From the observation of groundwater level and failure pattern, it was seen that the discharge from cliff made newly from slope failure induced the decrease of groundwater level and the successive slope failure was stopped.
