豪雨による土砂災害を対象としたリアルタイムハザードシステムの構築

摘要

Recently, intensive rainfalls have been becoming heavier than past, and, therefore, landslide disasters have been often occurring in many area, and damage of various facilities and lives have been large. The slope failure disasters occurred by the heavy rainfall that typhoon 9 caused at western and northern area in Hyogo prefecture in 2009. Spatial and temporal prediction of landslides is important to diminish the damage by such landslides, and it is necessary to gather the information of dangerous situation for the evacuation of the habitants. The real-time type hazard system has been constructing at Rokko mountain area in Hyogo prefecture from 2007, and it have been operating from April 2010. In this system, the prediction method of probability of failure occurring, using digital elevation model that Okimura and Ichikawa suggest, is installed, and the data of topography, geotechnical information, rainfall are used to calculate the safety factors of each cell that change real-timely at heavy rainfall. As the predicted results have been evaluated by the actual data of landslides caused by the heavy rainfall in 1967 July, the validity of this model has been showed enough. In this paper, the function and performance of this system are showed.%本論文では，現在，兵庫県が構築している六甲山系土rn砂災害危険度予測システムの概要を述べ，昭和42年災rn害の検証計算を行うことで本システムの妥当性を評価しrnた。パラメータの設定にあたっては，各種地質調査結果rnを人手し，それらを基に設定したが，その中で勾配と潜rn在崩壊土層探（表土層深）との関係については，崩壊予rn測値が実測値を再現できるように試行計算を行い，そのrn中で最適なものを抽出した。今後，他地域での解析結果rnが増えることによって精度が向上し，より広範な地域にrn適用していける解析条件，入力条件等設定できると思わrnれる。