Mechanism of seepage failure of ground with generation and evolution of air bubbles and its counter-measure
Project/Area Number |
18560485
|
Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Geotechnical engineering
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Research Institution | Nagoya Institute of Technology |
Principal Investigator |
MEDA Kenichi Nagoya Institute of Technology, Grad. School, Associate Professor (50271648)
|
Co-Investigator(Kenkyū-buntansha) |
NAKAI Teruo Nagoya Institute of Tech., Grad. School, Professor (00110263)
HO Cho Nagoya Institute of Tech., Grad. School, Professor (70303691)
HINOKIO Masaya Nagoya Institute of Tech., Grad. School, Research Assistant (00335093)
|
Project Period (FY) |
2006 – 2007
|
Project Status |
Completed (Fiscal Year 2007)
|
Budget Amount *help |
¥3,860,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥360,000)
Fiscal Year 2007: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2006: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
Keywords | seepage failure / air bubble / Demand Oxygen / progressive failure / PIV / SPH / coupling of three phases / unsaturated soil / 過飽和水 / SPH / 連成解析 |
Research Abstract |
Seepage failure including flowage deformation and hydraulic fracture plays an important role on geotechnical problems such as damage of dyke under flood, flow of ground caused by liquefaction. Moreover, generation of gas and blow-out of air bubbles have been seen before seepage failure occurred. The sources of air bubbles could be thought to be air phase entrapped by seepage front and oversaturated air in pore water. This means the generation and the development of air bubble play a very important role on seepage failure in nature. In this research, we focused the evolution effect of air bubbles in pore water on seepage failure of ground. We conducted model test, and developed a new numerical simulation method accounting for flowage deformation and solid-water-air bubbles interactions by Smoothed Particle hydrodynamics. Discrete analysis(e.g. DEM)is adapted to abruption, failure and flowage, but unsuitable procedure to analysis domain of large scale. Continuum analysis(e.g. conventional FEM)has opposite properties to that. The smoothed particle hydrodynamics method(SPH), a completely mesh-free technique, was used to obtain the combined benefits of both distinct and continuum methods. In this paper, SPH with a new method for calculating density, surface tension and multi-phases coupling was proposed. From model test results by using PIV image analysis, it was revealed that the evolution of air bubbles in the ground caused the degradation of the ground. The local degradation brings the evolution of bubbles. These chain reactions cause the macro seepage failure even under lower difference than the critical value. In numerical simulation, this research proposed a newly developed method of smoothed particle hydrodynamics(SPH) to solve three-phase systems(solid, liquid and gas). This paper shows clearly the validation and usefulness of SPH to be applicable for problems three phase
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Report
(3 results)
Research Products
(41 results)