Effect of hysteresis on the stability of residual soil slope
Soil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics. Matric suction in unsaturated residual soils changes with varying climatic conditions associated with cyclic drying-wetting conditions that result in hysteresis in the SWCC. The soil mechanical behaviour...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co., Ltd.
2019-09-01
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| Series: | International Soil and Water Conservation Research |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2095633918300789 |
| _version_ | 1797283566000799744 |
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| author | Christofer Kristo Harianto Rahardjo Alfrendo Satyanaga |
| author_facet | Christofer Kristo Harianto Rahardjo Alfrendo Satyanaga |
| author_sort | Christofer Kristo |
| collection | DOAJ |
| description | Soil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics. Matric suction in unsaturated residual soils changes with varying climatic conditions associated with cyclic drying-wetting conditions that result in hysteresis in the SWCC. The soil mechanical behaviour under wetting is crucial since numerous rainfall-induced slope failures occur during the wetting process. However, many slope stability analyses were carried out using drying SWCC. Consequently, the factor of safety (FoS) calculation may not represent the actual field condition. This paper presents the effect of hysteresis in SWCC on the stability of unsaturated residual soil slopes from Bukit Timah Granite in Singapore. The study focused on the analyses considering the differences in pore-water pressure and water content variations under drying and wetting conditions by performing numerical seepage and stability analyses. Each analysis was carried out on a slope subjected to dry and rainy periods under three different conditions: i) using only drying SWCC; ii) using only wetting SWCC; iii) using combined drying and wetting SWCCs. The results indicated that the FoS variations obtained from the numerical analyses incorporating combined SWCC matched more closely those obtained by incorporating only wetting SWCC than those obtained by incorporating only drying SWCC, regardless of the wetting or drying processes that the soil experienced. Moreover, the numerical analyses under high rainfall intensity by incorporating only wetting SWCC gave a more conservative FoS as compared to those obtained by incorporating combined SWCC. Numerical analyses incorporating only drying SWCC gave the most conservative FoS regardless of rainfall intensity. Keywords: SWCC, Hysteresis, Rainfall, Seepage, Slope stability |
| first_indexed | 2024-03-07T17:33:32Z |
| format | Article |
| id | doaj.art-fb038731c1804243a1f7a327bc3ea255 |
| institution | Directory Open Access Journal |
| issn | 2095-6339 |
| language | English |
| last_indexed | 2024-03-07T17:33:32Z |
| publishDate | 2019-09-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | International Soil and Water Conservation Research |
| spelling | doaj.art-fb038731c1804243a1f7a327bc3ea2552024-03-02T17:31:52ZengKeAi Communications Co., Ltd.International Soil and Water Conservation Research2095-63392019-09-0173226238Effect of hysteresis on the stability of residual soil slopeChristofer Kristo0Harianto Rahardjo1Alfrendo Satyanaga2School of Civil and Environmental Engineering, Nanyang Technological University, Hall of Residence 9, Block 46, #04-867, Singapore, 639811, SingaporeCorresponding author.; School of Civil and Environmental Engineering, Nanyang Technological University, Hall of Residence 9, Block 46, #04-867, Singapore, 639811, SingaporeSchool of Civil and Environmental Engineering, Nanyang Technological University, Hall of Residence 9, Block 46, #04-867, Singapore, 639811, SingaporeSoil-water characteristic curve (SWCC) is an essential parameter in unsaturated soil mechanics. Matric suction in unsaturated residual soils changes with varying climatic conditions associated with cyclic drying-wetting conditions that result in hysteresis in the SWCC. The soil mechanical behaviour under wetting is crucial since numerous rainfall-induced slope failures occur during the wetting process. However, many slope stability analyses were carried out using drying SWCC. Consequently, the factor of safety (FoS) calculation may not represent the actual field condition. This paper presents the effect of hysteresis in SWCC on the stability of unsaturated residual soil slopes from Bukit Timah Granite in Singapore. The study focused on the analyses considering the differences in pore-water pressure and water content variations under drying and wetting conditions by performing numerical seepage and stability analyses. Each analysis was carried out on a slope subjected to dry and rainy periods under three different conditions: i) using only drying SWCC; ii) using only wetting SWCC; iii) using combined drying and wetting SWCCs. The results indicated that the FoS variations obtained from the numerical analyses incorporating combined SWCC matched more closely those obtained by incorporating only wetting SWCC than those obtained by incorporating only drying SWCC, regardless of the wetting or drying processes that the soil experienced. Moreover, the numerical analyses under high rainfall intensity by incorporating only wetting SWCC gave a more conservative FoS as compared to those obtained by incorporating combined SWCC. Numerical analyses incorporating only drying SWCC gave the most conservative FoS regardless of rainfall intensity. Keywords: SWCC, Hysteresis, Rainfall, Seepage, Slope stabilityhttp://www.sciencedirect.com/science/article/pii/S2095633918300789 |
| spellingShingle | Christofer Kristo Harianto Rahardjo Alfrendo Satyanaga Effect of hysteresis on the stability of residual soil slope International Soil and Water Conservation Research |
| title | Effect of hysteresis on the stability of residual soil slope |
| title_full | Effect of hysteresis on the stability of residual soil slope |
| title_fullStr | Effect of hysteresis on the stability of residual soil slope |
| title_full_unstemmed | Effect of hysteresis on the stability of residual soil slope |
| title_short | Effect of hysteresis on the stability of residual soil slope |
| title_sort | effect of hysteresis on the stability of residual soil slope |
| url | http://www.sciencedirect.com/science/article/pii/S2095633918300789 |
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