Critical Rainfall on the Landslide at Shaluntz
Date Issued
2010
Date
2010
Author(s)
Huang, Yao-Hwei
Abstract
Abundant rainfall often causes landslides and debris flows on slopes, and even result in serious damage to lives and property of people. In order to strengthen the hardware with the limited facilities, we formulate the rainfall warning threshold value to warn and evacuate. However, if the estimate is conservative, it will lower the risk of people''s lives and property will raise..
In this study, we did the research in Shalunzi watershed in Shihmen Reservoir catchment. Based on past geological survey data, that the study area for the old colluviums, with an average thickness of about 20 meters. The characteristics of geological structure loosely and high permeability. In the study area, placed the 12 groundwater observation wells. Rainfall is likely to influence change in groundwater level. Reaction rate faster groundwater observation wells are distributed in the road. The study judged the road due to poor drainage. There are four observation wells have not read the data, the depth of the deepest underground 50 meters. Therefore, we judged that the ground water in deeper.
For the purpose of rainfall warning value, the study compiled information on geology and soil analysis, and considering the relationship between slope and soil moisture, and then estimate the hazard of the critical water content. In addition, comparison of typhoon rainfall and infiltration curve. Analysis results indicated that only a small part of the rainfall infiltration to the soil. Most of the rainfall became runoff causing soil erosion or the occurrence of shallow landslides. Finally, we divide the envelope index warning level of rainfall. This study modified the envelope index, with the cumulative rainfall by maximum and average rainfall intensity. It can narrow the scope of its rainfall warning, with Avery and Martha Typhoons are more consistent with the accumulated rainfall. Therefore, the modified rainfall warning value is divided potential into low, medium and high. Provide information for government to announce the reasonable rainfall warning threshold valueand the needed time for evacuation.
Subjects
rainfall warning value
groundwater monitoring
infiltration
slope stability
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-99-R97622020-1.pdf
Size
23.53 KB
Format
Adobe PDF
Checksum
(MD5):79e7f581a6b4944c03a92298ea4033a0