The inspection of the triggering mechanism for a hazardous mudflow in an urbanized territory

Abstract

On October 16, 1998, a mudflow of 2,000 m(3) resulting in five deaths in the Neihu area of Taipei city came in the wake of Typhoon Zebert, which delivered approximately 300 mm/day of precipitation. The destructive 50-m-long mudflow rushed down the hill without any forewarning, wreaking severe destruction to the properties below. Based on in-situ investigation, this paper discusses the event scenario and provides critical data analyses to identify the contributing factors and main triggering mechanism of the disaster. The chances of possible water uplift due to groundwater conditions, the engineering properties of the geomaterials, and the influence of man-made changes in the morphology are examined in weighing the importance of these factors and identifying the main trigger

Controlling factors of hazardous debris flow in Taiwan

“…Heavy precipitation commonly increases water content and pore water pressure, and generates a great volume of various geomaterials from the source areas (Chen et al, 2004). Initial movement of debris flow certainly begins with the rapid appearance of surface runoff water (Fig.…”