| Autor: |
Rick Vandoorne, Petrus J. Gräbe, G. Heymann |
| Rok vydání: |
2021 |
| Předmět: |
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| Zdroj: |
Lecture Notes in Civil Engineering ISBN: 9783030772376 |
| DOI: |
10.1007/978-3-030-77238-3_26 |
| Popis: |
Volumetric water content (VWC) and matric suction vary temporally in the foundation layers of pavements and railways due to various influencing environmental factors. The resilient and permanent deformation behaviors of railway foundation materials are strongly linked to the suction within the soil, reinforcing the need for the measurement thereof. This paper reports on the installation of VWC sensors, tensiometers and fixed-matrix soil-water suction sensors in different configurations within the foundation layers of a new 26 tonne/axle railway line near Ermelo in South Africa. Local weather data was recorded using a weather station at the site. The VWC sensors and the fixed-matrix soil-water suction sensors also monitored soil layer temperature. The measurement techniques used are critically compared with regard to their ability to respond to weather events. Practical aspects pertaining to the installation procedures and maintenance required for the different techniques are also reported. It was found that tensiometers require careful consideration to ensure pore-water continuity when installed in the field. Nonetheless, tensiometers were the most reliable and accurate form of measurement in this study. The use of VWC sensors to infer suction in silica flour is a novel idea. However, this method showed limited success in this study. Fixed-matrix soil–water suction sensors provided the best long-term stability and ease of installation. However, the accuracy of these sensors requires further investigation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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