By constructing an artificial perched watertable which is a horizontal and cylindrical soil cavity with a diameter of 3 m and a height of 0Á3 m, at a depth of about 0Á8 m from the soil surface in the fields, it was envisaged that the runoff caused in the summer could preferably be held in this layer
SW—Soil and Water: Construction of an Artificial Perched Watertable, Part 1: Air Permeability of Soils and Aspects of Soil Failure
✍ Scribed by K. Araya; G. Guo
- Book ID
- 102966006
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 905 KB
- Volume
- 81
- Category
- Article
- ISSN
- 1537-5110
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✦ Synopsis
The annual precipitation in the Three-river Plain of the People's Republic of China is only 500-600 mm and, besides, the rainfall is uneven; 60-70% of the annual precipitation occurs in July and August and there is almost no rainfall in the winter and spring seasons. Experiments were conducted to form the artificial perched watertable where the runoff caused in summer could preferably be held, by injecting high-pressure air into the soil. A horizontal soil cavity is required, so this paper deals with the determination of the air permeability of soils and the difference in the soil failure mechanisms due to the different air permeabilities.
The results show that the air permeability k of 10 m 2 s À1 MPa À1 defined the situation between the fluidization and the V-shaped soil failure. When the value of k was from 10 to 0Á1 m 2 s À1 MPa À1 , the V-shaped soil failure took place and when it was less than 0Á1 m 2 s À1 MPa À1 , the soil cavity production took place. In order to produce the soil cavity in the B horizon of the planosol or Cg1 horizon of the meadow soil by air injection, the value of k for these soils should be less than 0Á1 m 2 s À1 MPa À1 and the soil water content of these soils should be more than 30% d.b.
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