トータルステーション測量による徳島県西井川地すべりの挙動解析

Analysis of the Landslide Behavior with the Total Station Survey in Nishi-Ikawa, Tokushima Prefecture, Japan

森 格

笹井 康佑

井上 新平

Kaibori Masahiro

広島大学総合科学部紀要. IV, 理系編

Memoirs of the Faculty of Integrated Arts and Sciences, Hiroshima University. IV, Science reports

Total station surveying has been done to find out spatially the landslide behavior at the Nishi-Ikawa landslide area in the Tokushima Prefecture. Firstly, errors which were able to enter this surveying have been checked and evaluated in order to grasp correctly the landslide behavior by this surveying method, if human errors could be kept minimum. However, the authors found that the surveying result involved errors even in the each careful set up of the instrument and that obtained 3-dimensional coordinates could be not directly utilized to analyze the landslide behavior. Also, the surveying could be made only in the season from the late autumn to early spring due to the vegetation obstruction. However, it was clarified that the change of the distance between the instrument site and each observed point and the change of the distance among the instrument sites in each surveying could be used to grasp the landslide behavior. From the analytical consideration of the surveying data, the following things were clearly pointed out:(1)There was a compressive tendency on the total area of the Nishi-Ikawa landslide slope.(2)The landslide area consisted of five blocks.(3)The uppermost block moved downwards onto the lower block, and the three middle blocks seemed to be pushed to the outer sides.(4)The road construction with the cutting and filling in 1999 seemed to be not effective to the recent landslide behavior(5)The landslide behavior around the foot part of the lowest slope could not be prevented by the countermeasure with the existing retaining wall only.

座標測量

地すべり

測量精度

トータルステーション

面的挙動

coordinate surveying

landslide

spatial behavior

surveying accuracy

total station

Earth sciences. Geology [ 450 ]

jpn

広島大学総合科学部

[ISSN] 1340-8364

[NCID] AN10435936