A study on a instability slope in Taiwan subjected to rainfalls

2nd International Conference on Sustainable Development in Civil, Urban and Transportation Engineering

地球科学;运输工程;经济学

Hsiao, D.H.^1 ; Hsieh, C.S.^1 ; Yeh, L.C.^1 ; Lin, D.Y.^1 ; Phan, V.T.-A.^2

Department of Civil Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung

80778, Taiwan^1

Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Viet Nam^2

关键词: Frictional resistance;    Geological surface;    Lateral displacements;    Limit equilibrium;    Long term monitoring;    Pore-water pressures;    Rainfall infiltration;    Unsaturated soil;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/143/1/012018/pdf
DOI  :  10.1088/1755-1315/143/1/012018

来源: IOP

【 摘 要 】

After the long-term monitoring on the Chaishan area in Taiwan from 2005 to 2012 by Kaohsiung City Government, the obtained results showed that annual lateral displacements in the region are about 7-8cm to the Taiwan Strait. The geological surface profiles of Chaishan area are in sequence weathered limestone, clay layer, limestone and mudstone layer, respectively. Thus the frictional resistance between weathered soils and rock layer could decrease after infiltration of rainwater due to impervious to water of the lowest mudstone layer. Typhoon invades often Taiwan each year, resulting in rainfall infiltration and rising groundwater level, as well as increased pore water pressure within the soil mass, causing the earth movements in some parts of Chaishan, especially in the Temple A (Shan Hai Temple) accompanied with cracking phenomenon. In this paper, limit equilibrium (LE) and finite element method (FEM) are used for slope analysis, in which the slope is considered as unsaturated soil. Results showed groundwater amounts are easy to accumulate and increasing pore water pressure give resulting in decreased safety factor. Both of groundwater level and rain durations were also considered in this study.