Effect of Cross Section of Subsurface Drain on Its Performance

• Published in: Guanʻgai paishui xuebao Vol. 41; no. 6; pp. 131 - 139
• Main Authors: HAN Han, LI Mingsi, ZHANG Jinhua, LIU Xingshuang, XU Qiang, CHEN Wenjuan
• Format: Journal Article
• Language: Chinese
• Published: Science Press 01-06-2022
• Subjects: draining water and salt; reclamation of saline-alkali land; subsurface drain; unsaturated soil
• ISSN: 1672-3317
• DOI: 10.13522/j.cnki.ggps.2022009

【Objective】 Subsurface drain is an engineering technology to control groundwater table not exceeding a critical depth. Its performance depends not only on soil properties but also on design parameters. The purpose of this paper is to investigate the impact of geometrical configuration of the drain on its performance in controlling water and salt movement in the soil. 【Method】 We compared four cross sections: circular section with an impermeable drain bottom (T1); equilateral triangular section with an impermeable bottom; circular section with an impermeable wing at the drain bottom; equilateral triangular section with an impermeable wing at the drain bottom. All drains were made by metal wire meshes; they were wrapped by non-polyester filament and perforated non-woven geotextile filter layer. The drainage experiment was conducted in soil columns repacked with a sandy soil. Each column was irrigated by 7 L of water. During the experiment, we measured soil water movement around the drain; water flow in the soil