Method for predicting soil-water characteristic curve VG model based on water evaporation curve in soil
A water characteristic curve and curve technology, which is applied in the field of research on the relationship between water evaporation characteristics in soil and unsaturated soil water holding characteristics, can solve the problems of long time consumption and high cost, and achieve the effects of reduced test difficulty, simple operation and simple method
Active Publication Date: 2019-01-18
HUBEI UNIV OF TECH
View PDF3 Cites 5 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
The soil-water characteristic curve of the soil can be directly measured by the test method, but the cost is high and the time is long, and the test can only obtain the soil-water characteristic curve in a certain state of the soil.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.
[0034] According to the Young-Laplace equation, the matrix suction ψ is inversely proportional to the effective pore size r:
[0035]
[0036] In the formula: T s Indicates the surface tension; α indicates the contact angle, when the temperature is constant, 2T s cosα can be regarded as a fixed value.
[0037]In the evaporation test, for the same soil and other conditions are the same, the water in the large pores in the soil evaporates first, and the water in the small pores evaporates later, and the larger the pore size, the faster the internal water evaporation rate. Then, the evaporation curve (the relationship between soil sample moisture content and evaporation time) actually reflects the characteristics of soil sample moisture content and pore size distribution. On the other hand, according to formula (3), the soil-water...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| density | aaaaa | aaaaa |
Login to View More
Abstract
The invention discloses a method for predicting a soil-water characteristic curve VG model based on a water evaporation curve in soil. The method comprises the following steps: obtaining N evaporationcurves of a soil body under N different and known initial dry densities in which an evaporation mass water content w0 changes with an evaporation time t by using an indoor drying evaporation test, obtaining N soil-water characteristic curves under the N known dry densities according to experimental data, performing fitting based on a Van Genuchten model of a classical soil-water characteristic curve model to obtain N groups of fitting parameters aec, mec, nec, aswcc, mswcc and nswcc, and establishing a prediction model of soil-water characteristic curve parameters. The soil-water characteristic curve is predicted by using the evaporation curve, so that the workload of measuring the two curves by tests can be reduced, the test difficulty is greatly reduced, the soil-water characteristic curve is predicted more effectively, and then the unsaturated soil engineering properties can be researched more conveniently.
Description
technical field [0001] The invention relates to the technical field of research on the relationship between water evaporation characteristics in soil and water holding characteristics of unsaturated soil, in particular to a method for predicting a soil-water characteristic curve VG model based on water evaporation curves in soil. Background technique [0002] Evaporation of soil moisture is a dynamic process of water content reduction. Through indoor drying tests, external environmental factors such as temperature and humidity are controlled, and the change process of water loss of samples under dry conditions is monitored to obtain the evaporation curve of samples. The relationship between matric suction and water content in unsaturated soil is the soil-water characteristic curve, and the matric suction measured in the process of gradually reducing the saturation of saturated soil samples is the drying curve of the soil-water characteristic curve. Evaporation curves can ref...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): G01N5/04
CPCG01N5/045
Inventor 陶高梁罗晨晨肖衡林马强万娟朱志政付佩陈阳阳彭弯张琎炜
Owner HUBEI UNIV OF TECH