Abstract
Capillary barrier is a two-layer cover system having distinct hydraulic properties to minimize water infiltration into the underlying soil by utilizing unsaturated soil mechanics principles. In this study, the capillary barrier system was designed as a cover system for a residual soil slope to minimize infiltration during heavy rainfall in the tropics in order to maintain stability of the slope. The capillary barrier system was constructed using fine sand as the fine-grained layer and recycled crushed concrete aggregates as the coarse-grained layer. The coarse-grained layer is commonly constructed using gravels or granite chips. However, due to scarcity of aggregates and for consideration of environmental sustainability, recycled crushed concrete aggregates were used as the coarse-grained layer in this project. The suitability of a material such as recycled crushed concrete aggregates to be used as the coarse-grained layer of a capillary barrier system is determined by the hydraulic property requirement that is elaborated in this paper. The performance of the constructed capillary barrier system on the residual soil slope was monitored using tensiometers installed at different depths from 0.6 to 1.8 m below the slope surface and a rainfall gauge mounted on the slope. An adjacent original slope without the capillary barrier system was also instrumented using tensiometers and piezometers in order to investigate the performance and effectiveness of the capillary barrier system in reducing rainwater infiltration and maintaining negative pore-water pressures in the slope. Real-time monitoring systems were developed to examine pore-water pressure, rainfall and groundwater level in the slopes over a one-year period. Characteristics of pore-water pressure distributions in the residual soil slope under a capillary barrier system with recycled crushed concrete aggregates and in the original slope during typical rainfalls are highlighted and compared in this paper. The measurement results showed that the capillary barrier system was effective in minimizing rainwater infiltration and therefore, maintaining stability of the slope.
| Original language | English |
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| Title of host publication | Landslides and Engineered Slopes |
| Subtitle of host publication | Protecting Society through Improved Understanding - Proceedings of the 11th International and 2nd North American Symposium on Landslides and Engineered Slopes, 2012 |
| Editors | Erik Eberhardt, Corey Froese, A. Keith Turner, Serge Leroueil |
| Publisher | CRC Press/Balkema |
| Pages | 1593-1599 |
| Number of pages | 7 |
| ISBN (Print) | 9780415621236 |
| Publication status | Published - 2012 |
| Externally published | Yes |
| Event | 11th International Symposium on Landslides and 2nd North American Symposium on Landslides, 2012 - Banff, Canada Duration: Jun 2 2012 → Jun 8 2012 |
Publication series
| Name | Landslides and Engineered Slopes: Protecting Society through Improved Understanding - Proceedings of the 11th International and 2nd North American Symposium on Landslides and Engineered Slopes, 2012 |
|---|---|
| Volume | 2 |
Conference
| Conference | 11th International Symposium on Landslides and 2nd North American Symposium on Landslides, 2012 |
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| Country/Territory | Canada |
| City | Banff |
| Period | 6/2/12 → 6/8/12 |
Bibliographical note
Publisher Copyright:© 2012 Taylor & Francis Group, London.
ASJC Scopus Subject Areas
- Earth-Surface Processes
- Geotechnical Engineering and Engineering Geology