High Suction Double-Cell Extractor高吸力雙室提取器
- Summary
- Almost all soil slopes on land are initially unsaturated in nature. In order to determine the factor of safety of unsaturated slopes accurately, it is essential to calculate transient seepage and hence pore water pressures in the soil. To do so, one has to measure the so-called soil-water characteristic curve (SWCC), which defines the relationship between the soil suction and either the water content or the degree of saturation. Conventionally SWCC of a soil is measured by means of a pressure plate extractor in which no confining stress can be applied and volume change of the soil specimen is assumed to be zero, although it is recognized that the stress state of a soil will affect SWCC theoretically and volume change will take place when there is a change of soil suction and stress.
This is an invention relating generally to High Suction Double-Cell Extractor, and more specifically to Stress Controllable High Suction Double-cell Volumetric Pressure Plate Extractor. For accurate calculate pore water pressure distributions in unsaturated soil slopes for stability calculations and geoenvironmental engineering assessments, it is vital and essential to measure stress-dependent soil-water characteristic curve (SDSWCC) accurately under various stress states three-dimensionally and suctions up to 8,000 kPa. At present, no simple and accurate experimental system is available to measure SDSWCC under relevant field stress states and at high suctions.
The invention "Stress Controllable High Suction Double-cell Volumetric Pressure Plate Extractor", fill in the blank and it enables researchers and engineers to measure SDSWCCs accurately under various three-dimensional stress states and high suctions. This means that measured SDSWCC will be relevant to field stress conditions for transient seepage analysis of pore water pressure distributions, which are essential for accurate slope stability calculations and geoenvironmental engineering assessments.
- Technology Benefits
- 1. Simple
2. Accurate
- Technology Application
- - Laboratory measuring for engineering applications
- Supplementary Information
- Patent Number: US7793552B2
Application Number: US2008194312A
Inventor: Ng, Charles Wang Wai
Priority Date: 20 Aug 2007
Priority Number: US7793552B2
Application Date: 19 Aug 2008
Publication Date: 14 Sep 2010
IPC Current: G01N000308
US Class: 073818 | 073760
Assignee Applicant: The Hong Kong University of Science & Technology
Title: High suction double-cell extractor
Usefulness: High suction double-cell extractor
Summary: Pressure plate extractor for measurements of stress-dependent soil-water characteristic curve (SDSWCC), e.g. high suction double-cell extractor, and stress controllable high suction double-cell volumetric pressure plate extractor.
Novelty: Pressure plate extractor for measurements of stress-dependent soil-water characteristic curve (SDSWCC), e.g. high suction double-cell extractor, has port in outer wall for introducing pressurized air supply into vessel
- Industry
- Environmental/Green Technology
- Sub Category
- Water Processing
- Application Date
- 19 Aug 2008
- Application No.
- US 12/194312
- Patent Information
- US 7793552
- ID No.
- TTC.PA.294S
- Country/Region
- Hong Kong

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