Method for fast confirming hydraulic parameters of unsaturated soil

A hydraulic parameter and fast technology, applied in the field of hydraulic parameter testing of unsaturated soil, can solve the problems of affecting the test accuracy, long test time, and long time, so as to shorten the test time, break through the time-consuming and laborious, and improve the speed and accuracy. sexual effect

Inactive Publication Date: 2009-07-22
INST OF ROCK & SOIL MECHANICS CHINESE ACAD OF SCI
View PDF0 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In addition, because the traditional test method for determining the hydraulic parameters of unsaturated soil takes a long time, another unavoidable problem will be caused: the high-pressure gas flows through the water and precipitates on the back of the low-pressure high-intake value clay plate, Affect the test accuracy
[0010] ① The traditional test method for determining the hydraulic parameters of unsaturated soil is based on the measurement of the sample in a balanced state, which leads to a long test time;
[0011] ②The high-pressure gas diffuses through the water and precipitates on the back of the clay plate with a low pressure and high air intake value, which affects the test accuracy

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 more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for fast confirming hydraulic parameters of unsaturated soil
  • Method for fast confirming hydraulic parameters of unsaturated soil
  • Method for fast confirming hydraulic parameters of unsaturated soil

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0053] Below in conjunction with accompanying drawing and embodiment the present invention is further described:

[0054] 1. About step ①

[0055] A. Carry out multi-step flow test under certain conditions

[0056] use as figure 1 The multi-step flow test device shown is to connect the high-precision servo air pump 3, the sample loading container 2, the sample 1, the Teflon permeable membrane 6, the high air intake value clay plate 5 and the high-precision servo flow pump 4 in sequence. Subsequently, apply the figure 2 The relationship between capillary pressure and time is shown (at time t 1 , the capillary pressure p c0 Sudden increase by a small increment Δp c1 to capillary pressure p c1 , and keep it constant until t 2 moment; then, at t 2 time, the capillary pressure p c1 Sudden increase by a small increment Δp c2 to capillary pressure p c2 , and keep it constant until t 3 time; and so on, at t n time, the capillary pressure p c(n-1) Sudden increase by a smal...

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

No PUM Login to view more

Abstract

The invention discloses a method for quickly determining the hydraulic parameters of unsaturated soil, relating to a method for testing the hydraulic parameters of unsaturated soil. The method mainly comprises the following steps of: (1) developing a multi-step flow test under a certain condition to obtain the relation curve between the saturation and the time change, simultaneously, establishing a linear viscoelastic model that accurately describes the saturation of the specimen along the time change under the condition; (2) calculating the water tolerance Ci at unit pressure and the characteristic time tci under the effect of the capillary pressure pci; and (3) calculating the saturation (Sr)eqi and the filtration coefficient ki when the specimen is in the balance state under the effect of the capillary pressure pci. The invention relates to a method for determining the hydraulic parameters of unsaturated soil based on the multi-step flow test result under a certain condition. The method is also suitable to environmental evaluation of underground pollutants, rainfall infiltration and other fields related to unsaturated soil.

Description

technical field [0001] The invention relates to a method for testing hydraulic parameters of unsaturated soil, in particular to a method for rapidly determining hydraulic parameters of unsaturated soil. Background technique [0002] The hydraulic parameters of unsaturated soil include soil-water characteristic curve and seepage function. The soil-water characteristic curve describes the relationship between capillary pressure and water content; the permeability function describes the relationship between permeability coefficient and water content or capillary pressure. Through them, a series of problems such as the strength of unsaturated soil, volume strain, and the migration law of pollutants in the soil can be calculated. Therefore, unsaturated soil hydraulic parameters play an important role in solving problems related to unsaturated soil and seepage. [0003] There are three main categories of traditional test methods for determining the hydraulic parameters of unsatu...

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
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N15/08
Inventor 韦昌富陈辉魏厚振
Owner INST OF ROCK & SOIL MECHANICS CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products